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Posts Tagged ‘cardiac surgery’

cropped-mexicali-024.jpg

Free pdf:

Mexicali! a mini-gem guide to surgery in Baja, California

The pdf has been uploaded to Google books, and several other sites.

Low-cost e-format:  I managed to work out a kindle format, but Amazon.com won’t allow independent publishers to offer our books for free (except as part of a limited trial on KDP select.)  However, I have received several emails specifically asking for the Mexicali book to be placed on Amazon.com – so I am reluctantly doing so.  Please note that this e-format version is priced at the minimum – of 99 cents with a free download trial period.  (In case you are wondering, Amazon.com collects 65% of that.)

Update:

Paperback book:  The paperback version of the Mexicali book is now available!  I had hoped to offer a color version (for fans of medical photography) but for small-run books, it was going to be 28.00 a book, which seems excessive to me.  I’ve priced it at just above the cost to produce and offer it on Amazon channels for less than 7.00.

 

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Heading out-of-town for a conference for a few days – but in the meantime, I’ll be working one several case reports from recent surgeries.

We will also be talking about the latest stories from the Heart.org about the recent rise in off-label use of dabigatran (Pradaxa) use.

Rise in Pradaxa (dabigatran) linked to off-label use

Off-label uses

While this new anti-coagulant has been touted as the ‘easy’ alternative to warfarin since serum monitoring is not required – it is currently approved for the use of non-valvular atrial fibrillation only in the United States.

While it is approved for deep vein thrombosis prevention (DVT prophylaxis) in Europe – it is not, and should not be used for anti-coagulation in patients with mechanical valves.  

Off-label use in Canada leads to life-threatening complications

However, that is apparently exactly how doctors in Canada have been using it – with life-threatening consequences.  In a separate article at the Heart.org, doctors report that two female patients with mechanical valves who were recently switched from warfarin to dabigitran suffered from valvular thrombosis.

The “easy button” strikes again

More concerning, these patients had previously been successfully managed on warfarin without problems prior to the switch.  (So they were taken off a drug that was working well – and switched to a drug that is not approved for this condition because it was perceived to be easier to use.)

Within one month of the switch both patients began experiencing symptoms and were then diagnosed with valvular thrombosis.  Fortunately, neither of these patients died – but they certainly could have.

My former boss had a saying, “the enemy of good is better” meaning that if we try too hard to improve on something that is already working  – we unnecessary risk the lives and health of our patients.

Anticoagulants are not all the same

This just brings home the message that drugs that may seem similar, aren’t.  The way that dabigatran works is very different that warfarin, aspirin, clopidogrel (Plavix), abciximab (Reopro) or the other myriad of anti-coagulation type drugs.  Some of these drugs work on platelets – some of these drugs work on different parts of a complex mechanisms of coagulation (the coagulation cascade).   ‘Anti-coagulants’ is just a blanket term for these medications – and certainly doesn’t fully cover the intricacies of the pharmacology involved.  ‘Easy’ it isn’t – but medicine rarely is.

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It looks like the rest of the medical community is finally speaking up about the overuse and safety issues of TAVI/ TAVR for aortic stenosis, but it’s still few and far between – and in specialty journals…  But in the same week that Medscape, and the Heart.org reported on a newly published article in the British Medical Journal on the overuse of TAVI therapies, and the need for earlier diagnosis and treatment of Aortic Stenosis – the Interventionalists over at the Heart.org (a cardiology specialty journal)  have published a series of articles promoting / pushing the procedure including an article entitled, “The TAVR Heart team roles.”

JAMA recently published a paper by Robert Bonow and Chintan Desnai, discussing the benefits, risks and expectations with TAVI.  This paper discusses the very real need for clinicians to address heightened patient expectations regarding TAVI as an ‘easy’ alternative to surgery.

TAVI is vastly overused – Reed Miller, The Heart.org

Here at Cartagena Surgery – we’ve been doing our own research – contacting and talking to a multitude of practicing cardiologists and cardiac surgeons to get their opinions – in addition to reviewing the latest data.

In related news, a review of the latest research on the ‘transcatheter’ valve therapies demonstrates considerable concern: including data on peri-valvular leaks as reported in the last national TAVI registries in Europe and in the US:

The incidence of  paravalvular leaks  after TAVI is extremely high  ( > 60%)

• It is technically challenging today to quantify these leaks.

• Most of them are quoted “mild”, but more than 15 % are estimated  “moderate” and “severe”.

• In > 5% of patients, the peri-valvular or valvular regurgitation grade increased significantly over time.

• there is no significant difference between Edwards SAPIEN and Medtronic COREVALVE

As one cardiologist explained:

“Importantly, the thrombogenic potential of mild leaks was recently demonstrated by Larry Scotten ( Vivitro System Inc. Victoria, Canada). High reverse flow velocities expose glycoprotein GP Ib-IX-V  platelet receptors  to circulating Von Willebrand molecule with, as results, platelet aggregation and fibrin formation.  The incidence of brain spots and stroke after TAVI was of great concern in the PARTNER A and B studies.  Whereas, Aspirin is not mandatory  in  patients implanted with bioprosthetic valves,   Plavix +  Aspirin is recommended for all TAVI patients. The rationales of such therapy were not explained so far.”

Valve oversizing – a surgeon explains

“To reduce  these peri-valvular leaks , cardiologists tentatively use large valve size, up to 29-mm.  The very large majority of valve sizes used in conventional aortic valve replacement are smaller than 25-mm.  Oversizing may increase the risk of late aortic aneurysms (aortic rupture has been reported) [emphasis added].

Moreover, atrio-ventricular conduction may be impaired  with the need of permanent pacing. Poorer outcomes have been reported in patients when the need for permanent pacemaker occurs.

“As we like to say about clothes and shoes, you forget the price overnight but you remember the quality for ever . The price of TAVI may be cheaper but patients may experience inferior outcomes. In view of these results, using TAVI would not be appropriate for the great majority of  heart valve candidates.  Moreover trans-catheter delivery and sub-optimal fit are not likely to increase tissue valve durability…  and everybody knows that tissue valves are not enough durable for young adults and children.  TAVI is thus a suitable strategy only for the neglected population of high risk patients who are no longer candidates for surgery [emphasis added].

Worth pointing out again  that there would be no need for TAVI and long-term outcomes of patients would be much better if severe aortic stenosis were correctly managed at the right time.  Enclosed the recommendations of Robert Bonow   (Circulation, July 25, 2012) for early valve replacement in ASYMPTOMATIC  patients.  A large cohort of accurate biomarkers is available today for correct timing of surgery  and consequent prevention of  irreversible myocardium damage. In the study of Lancellotti (enclosed) 55% of “truly asymptomatic patients” with severe aortic stenosis developed pulmonary hypertension during exercise and had  poor clinical outcomes. The measurement of both mean trans-aortic pressure gradient and systolic pulmonary pressure, which are technically easy, rapid and with good reproducibility may improve the management of such patients.

These updates on the natural history of aortic stenosis illustrate the present paradoxical and intriguing  focus of the industry on an experimental procedural innovation for end-stage old patients when more efficient heart valves are today feasible and could be used sooner for the benefit of all patients .

Enclosed an article on The Need For A Global Perspective On Heart Valve from Sir Madgi Yacoub.

Additional Reference / supporting data:

Modified from  Ross J and Branwald E   (Circulation 1968 (Suppl): 61-67)

• The  incidence of stroke was 9% after TAVI in  the 214 patients of the enclosed study published last week in the American Journal of Cardiology. The incidence of stroke with TAVI was >  two times higher than with conventional surgery in the PARTNER study.  Pooled proportion of postoperative stroke was 2.4%  with conventional surgery  in the  large meta-analysis of patients > 80 years old (enclosed)

• Peri-valvular aortic insufficiency is observed in more than  60% of patients undergoing trans-catheter aortic valve replacement.  Moderate or severe aortic insufficiency was seen in 17.3 % of the PARTNER inoperable and high risk cohorts at 1 year.  They have been reportedly associated with dyspnea, anemia,  cardiac failure and diminished survival. Most interestingly,  the FDA does not accept more than  1%   peri-valvular insufficiency in patients implanted with conventional prosthetic heart valves… The SJM Silzone mechanical heart valve was re-called  because of peri-valvular leakage rate of…  1.5 % .

• Traditionally, aortic stenosis involving a 2-cuspid aortic valve has been a contraindication to TAVI.  Of 347 octogenarians and 17 nonagenarians  explanted valves , 78 (22%) and 3 ( 18%) had stenotic congenitally bicuspid aortic valve, respectively.  Because the results of TAVI are less favorable in patients with stenotic congenitally bicuspid valves, proper identification of the underlying aortic valve structure is critical when considering TAVI in older patients . More than 50% of patients with aortic stenosis have bicuspid aortic valve and are not, therefore,  good candidates for TAVI. Most importantly, the great majority of patients with calcified stenotic  bicuspid aortic valves is  young ( < 60 years old)  and not candidate for tissue valve replacement.

•  The French Registry of trans-catheter aortic-valve implantation in high-risk patients was published in the New England Journal of Medicine on May 3,  2012. It reports  3195 TAVI procedures during the last two years at 34 centers.

The mean age was 83 years.  The incidence of stroke was 4.1%.  Peri-prosthetic aortic regurgitation was 64 %. The rate of death was 24% at one year. At the same time, the meta-analysis published in the American Heart Journal reports 13,216     CONVENTIONAL AORTIC VALVE REPLACEMENT in patients > 80 years old.    The rate of death was 12.4%  at one year,   21.3%  at 3 years and  34.6%  at 5 years

 

Full references for works cited in text:

Bonow, R. O. (2012). Exercise hemodynamics and risk assessment in asymptomatic aortic stenosisCirculation 2012, July 25.

Lancelloti, P., Magne, J., Donal, E., O’Connor, K., Dulgheru, R., Rosca, M., & Pierard, L. (2012).  Determinants and prognostic significance of exercise pulmonary hypertension in asymptomatic severe aortic stenosis.  Circulation, 2012 July 25.

Takkenberg, J. J. M., Rayamannan, N. M., Rosenhek, R., Kumar, A. S., Carapitis, J. R., & Yacoub, M. H. (2008).  The need for a global perspective on heart valve disease epidemiology: The SHVG working group on epidemiology of heart disease founding statement.  J. Heart Valve Dis. 17 (1); 135 – 139.

Gilard M, Eltchaninoff H, Iung B, Donzeau-Gouge P, Chevreul K, Fajadet J, Leprince P, Leguerrier A, Lievre M, Prat A,Teiger E, Lefevre T, Himbert D, Tchetche D, Carrié D, Albat B, Cribier A, Rioufol G, Sudre A, Blanchard D, Collet F, Dos Santos P, Meneveau N, Tirouvanziam A, Caussin C, Guyon P, Boschat J, Le Breton H, Collart F, Houel R, Delpine S,Souteyrand G, Favereau X, Ohlmann P, Doisy V, Grollier G, Gommeaux A, Claudel JP, Bourlon F, Bertrand B, Van Belle E, Laskar M; FRANCE 2 Investigators. Collaborators (184). Registry of transcatheter aortic-valve implantation in high-risk patients. N Engl J Med. 2012 May 3; 366(18):1705-15 [full abstract below].

BACKGROUND:

Transcatheter aortic-valve implantation (TAVI) is an emerging intervention for the treatment of high-risk patients with severe aortic stenosis and coexisting illnesses.

We report the results of a prospective multicenter study of the French national transcatheter aortic-valve implantation registry, FRANCE 2.

METHODS:

All TAVIs performed in France, as listed in the FRANCE 2 registry, were prospectively included in the study. The primary end point was death from any cause.

RESULTS:

A total of 3195 patients were enrolled between January 2010 and October 2011 at 34 centers. The mean (±SD) age was 82.7±7.2 years; 49% of the patients were women.

All patients were highly symptomatic and were at high surgical risk for aortic-valve replacement. Edwards SAPIEN and Medtronic CoreValve devices were implanted in 66.9% and 33.1% of patients, respectively. Approaches were either transarterial (transfemoral, 74.6%; subclavian, 5.8%; and other, 1.8%) or transapical (17.8%).

The procedural success rate was 96.9%. Rates of death at 30 days and 1 year were 9.7% and 24.0%, respectively.

At 1 year, the incidence of stroke was 4.1%, and   the incidence of periprosthetic aortic regurgitation was 64.5%.

In a multivariate model, a higher logistic risk score on the European System for Cardiac Operative Risk Evaluation (EuroSCORE), New York Heart Association functional class III or IV symptoms, the use of a transapical TAVI approach, and a higher amount of periprosthetic regurgitation were significantly associated with reduced survival.

CONCLUSIONS:

This prospective registry study reflected real-life TAVI experience in high-risk elderly patients with aortic stenosis, in whom TAVI appeared to be a reasonable option.

Rutger-Jan Nuis, MSc,  Nicolas M. Van Mieghem, MD,  Carl J. Schultz, MD, PhD,  Adriaan Moelker, MD, PhD ,  Robert M. van der Boon, MSc, Robert Jan van Geuns, MD, PhD, Aad van der Lugt, MD, PhD,  Patrick W. Serruys, MD, PhD, Josep Rodés-Cabau, MD,  Ron T. van Domburg, PhD,  Peter J. Koudstaal, MD, PhD,  Peter P. de Jaegere, MD, PhD.  Frequency and Causes of Stroke During or After Trans-catheter Aortic Valve Implantation. American Journal of Cardiology Volume 109, Issue 11 , Pages 1637-1643, 1 June 2012 [full abstract provided].

Transcatheter aortic valve implantation (TAVI) is invariably associated with the risk of clinically manifest transient or irreversible neurologic impairment. We sought to investigate the incidence and causes of clinically manifest stroke during TAVI. A total of 214 consecutive patients underwent TAVI with the Medtronic-CoreValve System from November 2005 to September 2011 at our institution. Stroke was defined according to the Valve Academic Research Consortium recommendations. Its cause was established by analyzing the point of onset of symptoms, correlating the symptoms with the computed tomography-detected defects in the brain, and analyzing the presence of potential coexisting causes of stroke, in addition to a multivariate analysis to determine the independent predictors.  Stroke occurred in 19 patients (9%) and was major in 10 (5%), minor in 3 (1%), and transient (transient ischemic attack) in 6 (3%). The onset of symptoms was early (≤24 hours) in 8 patients (42%) and delayed (>24 hours) in 11 (58%). Brain computed tomography showed a cortical infarct in 8 patients (42%), a lacunar infarct in 5 (26%), hemorrhage in 1 (5%), and no abnormalities in 5 (26%). Independent determinants of stroke were new-onset atrial fibrillation after TAVI (odds ratio 4.4, 95% confidence interval 1.2 to 15.6), and baseline aortic regurgitation grade III or greater (odds ratio 3.2, 95% confidence interval 1.1 to 9.3).

In conclusion, the incidence of stroke was 9%, of which >1/2 occurred >24 hours after the procedure. New-onset atrial fibrillation was associated with a 4.4-fold increased risk of stroke. In conclusion, these findings indicate that improvements in postoperative care after TAVI are equally, if not more, important for the reduction of peri-procedural stroke than preventive measures during the procedure.

Sinning JM, Hammerstingl C, Vasa-Nicotera M, Adenauer V, Lema Cachiguango SJ, Scheer AC, Hausen S, Sedaghat A, Ghanem A, Müller C, Grube E,Nickenig G, Werner N. (2012).  Aortic regurgitation index defines severity of peri-prosthetic regurgitation and predicts outcome in patients after transcatheter aortic valve implantation.  J Am Coll Cardiol. 2012 Mar 27;59(13):1134-41. [full abstract provided].

OBJECTIVES:

The aim of this study was to provide a simple, reproducible, and point-of-care assessment of peri-prosthetic aortic regurgitation (periAR) during trans-catheter aortic valve implantation (TAVI) and to decipher the impact of this peri-procedural parameter on outcome.

BACKGROUND:

Because periAR after TAVI might be associated with adverse outcome, precise quantification of periAR is of paramount importance but remains technically challenging.

METHODS:

The severity of periAR was prospectively evaluated in 146 patients treated with the Medtronic CoreValve (Minneapolis, Minnesota) prosthesis by echocardiography, angiography, and measurement of the aortic regurgitation (AR) index, which is calculated as ratio of the gradient between diastolic blood pressure (DBP) and left ventricular end-diastolic pressure (LVEDP) to systolic blood pressure (SBP): [(DBP – LVEDP)/SBP] × 100.

RESULTS:

After TAVI, 53 patients (36.3%) showed no signs of periAR and 71 patients (48.6%) showed only mild periAR, whereas 18 patients (12.3%) and 4 patients (2.7%) suffered from moderate and severe periAR, respectively. The AR index decreased stepwise from 31.7 ± 10.4 in patients without periAR, to 28.0 ± 8.5 with mild periAR, 19.6 ± 7.6 with moderate periAR, and 7.6 ± 2.6 with severe periAR (p < 0.001), respectively. Patients with AR index <25 had a significantly increased 1-year mortality risk compared with patients with AR index ≥25 (46.0% vs. 16.7%; p < 0.001). The AR index provided additional prognostic information beyond the echocardiographically assessed severity of periAR and independently predicted 1-year mortality (hazard ratio: 2.9, 95% confidence interval: 1.3 to 6.4; p = 0.009).

CONCLUSIONS:

The assessment of the AR index allows a precise judgment of periAR, independently predicts 1-year mortality after TAVI, and provides additional prognostic information that is complementary to the echocardiographically assessed severity of periAR.

Gotzmann M, Lindstaedt M, Mügge A. (2012). From pressure overload to volume overload: Aortic regurgitation after transcatheter aortic valve implantation.  Am Heart J. 2012 Jun;163(6):903-11.  [full abstract provided].

Severe aortic valve stenosis is a common valvular heart disease that is characterized by left ventricular (LV) pressure overload. A lasting effect of pressure overload is LV remodeling, accompanied by concentric hypertrophy and  increased   myocardial stiffness. Transcatheter aortic valve implantation (TAVI) has emerged as an alternative to surgical aortic valve replacement for patients with severe symptomatic aortic valve stenosis and high surgical risk.   Although TAVI has  favorable hemodynamic performance, aortic valve regurgitation (AR) is the most frequent complication because of the specific technique used for implantation of transcatheter valves.

During  implantation, the calcified native valve is pushed aside, and the prosthesis usually achieves only an incomplete prosthesis apposition. As a consequence, the reported prevalence of moderate and severe AR after TAVI is  6% to 21%,  which is considerably higher than that after a surgical valve replacement. Although mild AR probably has minor hemodynamic effects, even moderate AR might result in serious consequences. In moderate and   severe  AR  after TAVI,  a normal-sized LV with increased myocardial stiffness has been exposed to volume overload. Because the noncompliant LV is unable to raise end-diastolic volume, the end-diastolic pressure increases, and  the  forward stroke volume    decreases. In recent years, an increasing number of patients have successfully undergone TAVI. Despite encouraging overall results, a substantial number of patients receive neither symptomatic nor prognostic benefits from TAVI.   Aortic valve regurgitation has been considered a potential contributor to morbidity and mortality after TAVI. Therefore, various strategies and improvements in valve designs are mandatory to  reduce the prevalence of AR after TAVI.

Walther T , Thielmann M, Kempfert J, Schroefel H, Wimmer-Greinecker G, Treede H, Wahlers T, Wendler O. (2012). PREVAIL TRANSAPICAL: multicentre trial of transcatheter aortic valve implantation using the newly designed bioprosthesis (SAPIEN-XT) and delivery system (ASCENDRA-II).  Eur J Cardiothorac Surg. 2012 Aug;42(2):278-83. Epub 2012 Jan 30.  [full abstract provided].

OBJECTIVE

Transapical (TA- aortic valve implantation (AVI) has evolved as an alternative procedure for high-risk patients.  We evaluated the second-generation SAPIEN xt ™ prosthesis in a prospective multicentre clinical trial.

METHODS

A total of 150 patients  (age : 81.6;  40.7 % female) were included. Prosthetic valves (diameter :23 mm (n= 36), 26 mm (n= 57) and 29 mm (n= 57) were implanted. The ASCENDRA-II™ modified delivery system was used in the smaller sizes.   Mean logistic EuroSCORE was  24.3%  and mean STS score was 7.5 ± 4.4%.  All patients gave written informed consent.

RESULTS:

Off-pump AVI was performed using femoral arterial and venous access as a safety net.  All but two patients receivec TA-AVI, as planned.  The 29-mm valve showed similar function as the values of two other diameters did.  Three patients (2%) required temporary bypass support.

Postoperative complications included renal failure requiring long-term dialysis in four, bleeding requiring re-thoracotomy in four, respiratory complication requiring re-intubation in eight and septsis in four patients, respectively.

Thirty day mortality was 13 ( 8.7%)  for the total cohort and 2/57  (3.5%) receiving the 29 mm valve respectively.   Echocardiography at discharge showed none or trivial incompetence (AI) in  71%  and mild-AI in 22% of the patients.  Post-implantation AI was predominantly para-valvular and > 2+  in 7% of patients.  One patient required re-operation for AI within 30 days.

CONCLUSION

The PREVAIL TA multicenter trial demonstrates good functionality and good outcomes for TA-AVI, using the SAPIEN xt ™ and its second generation ASCENDRA-II™ delivery system, as well successful  introduction of the 29-mm  SAPIEN XT ™ valve for the benefit of high-risk elderly patients.

Subramanian S, Rastan AJ, Holzhey D, Haensig M, Kempfert J, Borger MA, Walther T, Mohr FW. (2012).  Conventional Aortic Valve Replacement in Transcatheter Aortic Valve Implantation Candidates: A 5-Year ExperienceAnn Thorac Surg.   July 19 2012  [full abstract provided].

BACKGROUND:

Patient selection for transcatheter aortic valve implantation (TAVI) remains highly controversial. Some screened patients subsequently undergo conventional aortic valve replacement (AVR) because they are unsuitable TAVI candidates. This study examined the indications and outcomes for these patients, thereby determining the efficacy of the screening process.

METHODS:

Between January 2006 and December 2010, 79 consecutive patients (49% men), aged older than 75 years with high surgical risk, were screened for TAVI, but subsequently underwent conventional AVR through a partial or complete sternotomy. The indications, demographics, and outcomes of this cohort were studied.

RESULTS:

Mean age was 80.4 ± 3.6 years. Mean left ventricular ejection fraction was 0.55 ± 0.16, and the mean logistic European System for Cardiac Operative Risk Evaluation was 13% ± 7%. Of the 79 patients, 6 (7.6%) had prior cardiac surgical procedures. Indications for TAVI denial after patient evaluations were a large annulus in 31 (39%), acceptable risk profile for AVR in 24 (30%), need for urgent operation in 11 (14%), and concomitant cardiovascular pathology in 5 (6%). Mean cross-clamp time was 55 ± 14 minutes, and cardiopulmonary bypass time was 81 ± 21 minutes. Concomitant procedures included a Maze in 12 patients (15%). Postoperative morbidity included permanent stroke in 2 (2.5%), respiratory failure in 9 (11%), and pacemaker implantation in 2 (2.5%). Hospital mortality was 1.3% (1 of 79). Cumulative survival at 6, 12, and 36 months was 88.5%, 87.1% and 72.7%, respectively.

CONCLUSIONS:

Our existing patient evaluation process accurately defines an acceptable risk cohort for conventional AVR. The late mortality rate reflects the advanced age and comorbidities of this cohort. The data suggest that overzealous widening of TAVI inclusion criteria may be inappropriate.

Industry fights back

Now it looks like Edwards Lifesciences,  the company that manufacturers the Sapien valve is speaking out to dispute recent findings that show TAVI to have less than optimal results.  Of course, the author at the site, Med Latest says it best, “Setting aside the conflict of interest stuff, which might be a red-herring, what we’re left with is a situation where evidence-based medicine, while being something all would sign up to, is not that straightforward.”


[1] Several cardiologists and cardiac surgeons contributed to this article.  However, given the current politics  within cardiology, none of these experts were willing to risk their reputations by publically disputing the majority opinion.  This is certainly understandable in today’s medico-legal climate in wake of widespread scandals and credibility issues. However, all quotes are accurate, even if unattributable with minor formatting (such as the addition of quotations, and paragraph headings have been added for increased clarity of reading in blog format.)  I apologize for the ‘anonymous nature’ of my sources in this instance – however, I can assure you that these ‘experts’ know what they are talking about.

  [All commentary by Cartagena Surgery are in italics and brackets]. 

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Recently readers have contacted Cartagena Surgery to contribute to our many ongoing discussions on issues in cardiology, and cardiac surgery.

One of the points that readers have brought up has been the massive attention that TAVI/ TAVR has gotten from the media (and admittedly, we here at Cartagena Surgery are guilty of this), to the detriment of other issues in medicine and surgery.

In an attempt to address this very valid comment, we have started a series of posts looking at other issues in cardiac surgery – specifically in the area of valvular disease(s) and valvular replacement – and why it is important to re-focus our attention to these conditions such as infective endocarditis, mitral and tricuspid valve disorders, as well as bicuspid aortic valve disease.

Valve Disease and Dr. Didier  Lapeyre

In a current environment where TAVI/ TAVR dominate the landscape of discussion regarding valvular disease, other serious and persuasive problems in valvular disease treatments remain largely unaddressed.  The domination of conversations and considerations regarding the use of ‘less invasive’ mechanisms to correct aortic stenosis in the extreme elderly is something that could only be considered in the wealthiest of nations.

Burden of disease

Elsewhere in the world, and in the minds of more globally aware citizens, more important consideration is given to the burden of valvular disease across all populations including young adults and children.  In fact, in my limited travels, it is this scenario that encountered with much more frequency than the “frail octogenarian” that TAVI is designed for.

(For information on the burden of valvular disease in emerging countries – read The Need For A Global Perspective On Heart Valve Disease Epidemiology. )

Then why, as so many other cardiac surgeons and other authors have asked – are we expending some many resources on this minority population[1] to the exclusion and detriment of other developments in cardiac surgery?

Does TAVI detract attention from more common problems in cardiac surgery?

Some may argue, that TAVI/ TAVR is adjacent to, not exclusive to, the development of other improvements and advancements in the field but in my opinion that is a naïve view of the world.  Money and resources are not endless, and corporations and institutions expending large sums investing in transcatheter therapies are certainly not devoting similar resources to such mundane causes such as improving existing therapies.

Dr. Didier Lapeyre

But sometimes it takes a leader, and a legend to do these things, and that’s where Dr. Didier Lapeyre comes in.  As one of the original innovators of mechanical valve technology, he is not content to rest on his laurels or in the pages of medical textbooks.  As he and his colleagues note, current mechanical valve technologies continue to leave much to be desired.  As Zilla et. al. noted back in 2007, “Prosthetic heart valves: catering for the few?” this technology has been essentially stagnant for the last several years despite an enormous need, worldwide for a safe, durable mechanical valve.

Current therapies for valvular disease consist of two options; each with significant drawbacks.  The bioprosthetic or tissue valve requires no additional therapies after implantation but durability leaves much to be desired, making it inappropriate for most young candidates.

The trials and limitations of true mechanical valves are well-known.  As a foreign, metallic material, these valves are prone to cause platelet breakage, and hypercoagulability.  This leads to the dreaded thromboembolic complications of valve thrombosis and cerebral vascular accident.

If the heightened risk of post-TAVI stroke gives us pause in our frail elderly population, consider the elevated risks inherent with mechanical valves and their target population; children and young adults.

At present, the current solution of lifetime anticoagulation for patients with mechanical valves is a stopgap solution at best.  Problematic, potentially dangerous, and unpredictable are excellent descriptions of anti-coagulation with warfarin.  Unavailable and unrealistic are often as accurate; particularly when describing potential use in third-world populations.

After a recent post, talking about controversies and discussions in cardiac surgery in regards to TAVI, Dr. Lapeyre contacted Cartagena Surgery to add his thoughts on the issue.

This has opened a dialogue – and offers a new and interesting opportunity for my readers to hear about Dr. Lapeyre, his work, and (hopefully), the future of mechanical valves in addition to talking about related valvular conditions and treatments.


[1]  As we have argued several times, at Cartagena Surgery, many of the people who have been deemed ‘frail elderly ‘by their cardiologists can be successfully treated with conventional surgery.

References

Current Anti-coagulation recommendations:

Whitlock RP, Sun JC, Fremes SE, Rubens FD, Teoh KH; American College of Chest Physicians.  2012. Antithrombotic and thrombolytic therapy for valvular disease: Antithrombotic Therapy and Prevention of Thrombosis, 9th ed: American College of Chest Physicians Evidence-Based Clinical Practice Guidelines. Chest. 2012 Feb;141(2 Suppl):e576S-600S.

Akhtar RP, Abid AR, Zafar H, Khan JS. (2009).  Anticoagulation in patients following prosthetic heart valve replacement.  Ann Thorac Cardiovasc Surg. 2009 Feb;15(1):10-7. Study from Pakistan, where rheumatic heart disease remains common.  Also looks at genetic and racial differences in response to anti-coagulation. Readers will also notice that this study demonstrates the wide disparities in global medicine as discussed above.  How many western patients received a ball and cage valve in 2003?

Cannegieter SC, Rosendaal FR, Briët E. (1994).  Thromboembolic and bleeding complications in patients with mechanical heart valve prostheses.   Circulation. 1994 Feb;89(2):635-41.  Review.  [Linked in text above.]  While this article is considerably dated (based on data prior to 1993) it gives an excellent overview of the many problems/ complications in mechanical valve replacement. However, the statistics cited in their work may differ considerably from more recent results. (Presumably, the rate of ‘real world’ complications are much higher than what I see cited here.)

Matsuyama K, Matsumoto M, Sugita T, Nishizawa J, Yoshida K, Tokuda Y, Matsuo T. (2002).  Anticoagulant therapy in Japanese patients with mechanical mitral valves.  Circ J. 2002 Jul;66(7):668-70. A smaller scale Japanese study.

Not available as free text: Links to abstracts, when available

Taniguchi S, Hashizume K, Ariyoshi T, Hisata Y, Tanigawa K, Miura T, Odate T, Matsukuma S, Nakaji S, Eishi K. (2012).  Twelve years of experience with the ATS mechanical heart valve prostheses.  Gen Thorac Cardiovasc Surg. 2012 Jul 6.

Van Nooten GJ, Caes F, François K, Van Bellleghem Y, Bové T, Vandenplas G, Taeymans Y.  (2012).  Twenty years’ single-center experience with mechanical heart valves: a critical review of anticoagulation policy.  J Heart Valve Dis. 2012 Jan;21(1):88-98

Brown JW, Fiore AC, Ruzmetov M, Eltayeb O, Rodefeld MD, Turrentine MW. (2012).  Evolution of mitral valve replacement in children: a 40-year experience.  Ann Thorac Surg. 2012 Feb;93(2):626-33; discussion 633. Epub 2011 Dec 7. This article talks about why we still need to improve and innovate new valve technology – high mortality in this population.

Suri V, Keepanasseril A, Aggarwal N, Chopra S, Bagga R, Sikka P, Vijayvergiya R. (2011).  Mechanical valve prosthesis and anticoagulation regimens in pregnancy: a tertiary centre experience.  Eur J Obstet Gynecol Reprod Biol. 2011 Dec;159(2):320-3. Epub 2011 Oct 1.  Another important issue that affects our decisions to use mechanical or tissue valves.

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Had an amazing day yesterday – one of those days that reminds you how much we can do in medicine when we all work together.  I am hoping to write it up as a case study – if not – I will tell you more about it here.  (The patient was exceedingly gracious when I asked permission.)

But this morning, I was back in the operating room with Dr. Cuauhtemoc Vasquez.  (If he is tired of me – he sure doesn’t let on..)

I finally had the opportunity to get some of the pictures I’ve been trying to get on every visit to his OR – to show readers the heart, and the pulse of cardiac surgery..

There’s a running joke in Mexicali – if you need help in the operating room, any operating room, in any of the hospitals in the city; just holler for Lupita because she’s always there.

Introducing Lupita Dominguez, surgical nurse

All kidding aside on the popularity of the name “Lupita” among operating room personnel, there is just one Lupita that I would like to talk about today,  Lupita Dominguez, who is Dr. Vasquez’s surgical nurse.  In the months, and the numerous occasions that I have been a guest in Dr. Vasquez’s operating room, I’ve had the opportunity to observe and appreciate the hard-working Lupita.

Lupita Dominguez with Dr. Vasquez

Teacher, Coordinator and Mind-Reader

Most people don’t know it – but Lupita has the hardest job in the operating room, and probably (in Mexico) the most poorly paid.   They say a good scrub nurse has the instrument in the surgeon’s hand before he knows he needs it – and from what I’ve seen, that’s Lupita.  She’s here an hour earlier than the rest of the surgical team, getting everything ready, and she’ll be here after everyone else escorts the patient to the intensive care unit.

Here she is, a blur of motion as she takes care of everyone at the operating room table

As I watch again today, she is ‘running the table’ and anticipating the needs of not just one demanding cardiac surgeon, and an additional surgeon, but also one surgical intern, and another student.  With all of these people crowded at the table, she still has to follow the surgery, anticipate everyone’s needs and keep track of all the instruments and supplies in use.  In the midst of this maelström, the scrub nurse has to ensure that everyone else maintains sterility while preventing surgical instruments from being knocked to the floor, or otherwise misplaced (a difficult task at times).

Here she is demonstrating how to correctly load the needle, and pass sharp instruments

She’s forever in motion which has made taking the few photos of her a difficult endeavor; She’s shaving ice for cardioplegia, while listening to the circulator, adjusting the OR lights, and gently guiding the apprentices.  She’s so gentle in her teaching methods that the student doesn’t even realize she’s being led, and relaxes enough to learn.  This is no easy task, particularly since it’s just the beginning of the July, and while bright-eyed, pleasant and enthusiastic, the new surgical resident is inexperienced.  Her own student nurse, is two parts shy, but helpful enough that near the end of the case, (and the first time since I’ve known her), Lupita actually stops for a moment and flashes me a wave when she sees the camera faced in her direction.  I’m surprised, but I manage to capture it.

a very rare moment – Lupita takes a millisecond to say hello

She is endlessly busy, but ever uncomplaining – even when a scheduled surgery takes an unexpected turn and extends to twelve or even fourteen hours.  Bladder straining perhaps, baby-sitter calling, but Lupita never complains.  She’s not unique in that – scrub nurses around the world endure long hours, tired feet and legs, hungry bellies, full bladders, and aching backs as they complete their days in the operating room.  But she does it with good nature and grace.

Lupita assisting Dr. Vasquez during surgery

The surgical nurse

In the United States, this important job has been lost to nursing, a casualty of the ongoing shortage.  Positions such as scrub nurse and others like it have been frequently replaced with technicians who require less training and thus, less compensation that nurses.  Maybe the nursing profession doesn’t mourn the loss; but I do.

as you can see – here she is, ‘behind the scenes’ so to speak..

But in Mexico, and many other locations, this position remains the exclusive domain of the nurse.  Nurses such as Lupita, spend three years studying general nursing in college, before completing an (optional) additional year of training for a specialty such as the operating room.  After completing this training, these nurses spend yet another year in public service.

The idea of the public service requirement is honorable yet almost ironic (to me)  at times, since the majority of nurses in Mexico will spent their careers in public facilities, and by definition (in my mind at least), nursing is an occupation almost entirely devoted to the service and care of others.

Working conditions vary but some constants

Depending on the country, the culture, and the facility; conditions may vary; nurses may get short breaks, or be relieved during particularly long cases.   The only constant is the cold, and the hard floors, and rickety stepstools[1].  While the nurses here tell me that the workday is only seven hours long – I’ve been in the operating room with these ladies before, and watched a supposed ‘seven-hour’ day stretch to fifteen.   But it is just part of being a nurse.

[Usually I tell people when I am writing about them – but on this instance – there was never an opportunity.. but she (and all the nurses in the OR with Dr. Vasquez) certainly deserve mention.]


[1] Temperatures are set lower in cardiac surgery rooms.  Why the stepstools always seem rickety, I have no idea.

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Thanks again to ‘Lapeyre’, who as it turns out is Dr. Didier Lapeyre, a renowned, French cardiothoracic surgeon credited with the development of the first mechanical valves.

Dr. Didier Lapeyre was gracious enough to send some additional literature to add to our ongoing discussions regarding severe aortic stenosis and TAVI/ TAVR therapies.  He also commented that the best way to avoid these ‘high risk situations’ is by earlier intervention with conventional surgery – something we discussed before in the article entitled, “More patients need surgery.”

He also points out that ‘elderly’ patients actually do quite well with aortic valve replacement and offers a recently published meta-analysis of 48 studies on patients aged 80 or older.

As readers know, on June 13, 2012 – the FDA ruled in favor of expanding the eligibility criteria for this therapy.  Previously, this treatment modality, due to its experimental nature and high rate of complications including stroke and serious bleeding, has been limited in the United States to patients deemed ineligible for aortic valve replacement surgery.

Now on the heels of the Partner A trial, in which researchers reported favorable results for patients receiving the Sapien device, the FDA has voted to approve expanding criteria to include patients deemed to be high risk candidates for surgery.  As we have discussed on previous occasions, this opens the door to the potential for widespread abuse, misapplication of this therapy and potential patient harm.

In the accompanying 114 page article, “Transcatheter aortic valve implantation (TAVI): a health technology assessment update,” Belgian researchers (Mattias, Van Brabandt, Van de Sande & Deviese, 2011) looking at transcatheter valve procedures have found exactly that in their examination of the use of TAVI worldwide.

Most notably, is the evidence of widespread abuse in Germany (page 49 of report), which has become well-known for their early adoption of this technology, and now uses TAVI for an estimated 25 – 40% of valve procedures*.  Closer examination of the practices in this country show poor data reporting with incomplete information in the national registry as well as a reported mortality rate of 7.7%, which is more than double that of conventional surgery.  Unsurprisingly, in Germany, TAVI is reimbursed at double the amount compared to conventional surgery**, providing sufficient incentive for hospitals and cardiologists to use TAVI even in low risk patients. (and yes, german cardiologists are often citing “patient refused surgery” as their reason, particularly when using TAVI on younger, healthy, low risk patients.)

In their examination of the data itself, Mattias et al. (2011) found significant researcher bias within the study design and interpretation of results.  More alarmingly, Mattias found that one of the principle researchers in the Partner A study, Dr. Martin Leon had major financial incentives for reporting successful results.  He had recently received a 6.9 million dollar payment from Edward Lifesciences, the creators of the Sapien valve for purchase of his own transcatheter valve company.   He also received 1.5 million dollar bonus if the Partner A trial reached specific milestones.  This fact alone, in my mind, calls into question the integrity of the entire study.

[Please note that this is just a tiny summary of the exhaustive report.]

Thank you, Dr. Lapeyre for offering your expertise for the benefit of our readers!

* Estimates on the implantation of TAVI in Germany vary widely due to a lack of consistent reporting.

** At the time of the report, TAVI was reimbursed at 36,000 euros (45,500 dollars) versus 17,500 euros (22,000 dollars) for aortic valve replacement.

For more posts on TAVI and aortic stenosis, see our TAVI archive.

References

Mattias, N., Van Brabandt, H., Van de Sande, S. & Deviese, S. (2011).  Transcatheter aortic valve implantation (TAVI): a health technology assessment .  Belgian Health Care Knowledge Centre.

Vasques, F., Messori, A., Lucenteforte, E. & Biancari, F. (2012).  Immediate and late outcome of patients aged 80 years and older undergoing isolated aortic valve replacement: a systematic review and meta-analysis of 48 studies.  Am Heart J 2012; 163: 477-85.

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For internet searches for medical photography – all of my images are free for your use, but please give proper credit for my work, ie. “Photo by K. Eckland”.  For commercial uses, contact me, (so that I can contact the subjects of my work).

Please note that patient privacy is protected – and patient permission is obtained prior to photographs.  For the most part – I photograph surgeons – not patients, or surgery.

Spent much of the weekend in the operating room with Dr. C. Vasquez, cardiac surgeon at two different facilities, and the differences couldn’t be more apparent – and perhaps not what one might expect.  Much of it comes from perspective; as a person behind the lens, I see the scene differently than others might.

harvesting the radial artery

In fact, this prompted me to write an article on the subject of medical photography, complete with a slide show to illustrate the effects of color on surgical photographs. I’ve also re-posted much of the article here (see below).  Once you see the photos from today, you’ll understand the article.

the beige operating room

The case today went beautifully, with the patient extubated in the operating room.

Dr. Vasquez, and Lupita, scrub nurse

While we were there – had an unexpected surprise! Dr. Gutierrez ‘Lalo’ showed up.  I have been trying to get him into the cardiac OR since he confessed his interest in cardiac surgery.  It was great to see him – and I like encouraging him in his educational goals.   (I kind of miss being a mentor, and preceptor to students..)

Lalo peeks over the curtain..

Dr. Gutierrez (Lalo) in the cardiac OR

Medical Photography

Medical photography is many ways is more art, and luck that skill – at least for people like me who never set out to be medical photographers in the first place.  It was a natural development prompted by dire necessity during the early days of interviewing surgeons and medical writing.  I am still learning, and hopefully improving.

But as I said before, much of it is luck, and timing, particularly in this field, where the subjects are always in motion and a slight movement of the hand tying the suture knot can result in either a breath-taking shot or an utter failure to capture the moment.

The most dramatic and vivid photographs often come at mundane moments, or unexpected situations.  In medical photography, where the subject matter combines with a dramatic interplay of color, light and shadow to illustrate some of life’s most pivotal moments such as birth, death and life-saving operations – it is surprising how important the background elements are.

Here in Mexicali, I have been taking photographs of different surgeons for several weeks at different facilities across the city.  But, almost unanimously, all of the photographs, regardless of subject at Hospital Almater are lackluster and uninspiring.  Contrast this with the glorious photos from the public facilities such as Hospital General de Mexicali, and Issstecali.

The culprit is immediately apparent, and it demonstrates how such carefully planned such as aesthetics and interior design can have unintended consequences.  The very studied, casual beigeness used to communicate upscale living in the more public parts of the hospital are destroying the esthetics of the operating room services they are selling.  Whereas, the older facilities, which have continued the use of traditional colored drapes and materials do not have the problem.

Historically, surgical drapes were green for a very specific reason.  As the complementary color to red, it was believed to be a method of combating eye fatigue for surgeons looking at the red, bloody surgical fields for hours at a time.  Over the years, operating room apparel and drapes evolved away from this soft green to a more vivid blue, know as ‘ceil’.  The reasons for this change are probably more related to manufacturing that medicine, and since that evolution, surgical drapes now come in a variety of colors – hence the color matching here, of the paint, the tile, the patients, the operating room and the surgeons itself.  Somewhere, an interior decorator is filled with gleeful satisfaction – but I can only muster up a groan; knowing I will be here again and that most of my photos will be unusable.

While the consequences of poor medical photographs may seem trivial to anyone but myself (and my interviewees) at this junction – it runs far deeper than that.  With the advent of the internet, and the complicated legalities of getty and other corporate images, small, independent photographers such as myself are gaining wider exposure than ever before.   Alas! – much of it is uncredited, but several of my more popular images are downloaded thousands of times per week, to grace slideshows, powerpoint presentations and other illustrations for discussions of anything from medicine and surgery to travel, technology and even risk assessment.  In an era of branding, and logo recognition, places like Hospital Almater are certainly missing out.

In  other news/ happenings: Upcoming elections!**

Finally found someone to talk to and explain some of the issues in Mexican politics – but he hates Quadri, and doesn’t really explain any of it except to say ‘He’s corrupt..”  (From my understanding, ‘corrupt’ is an understatement, and that all of the parties are corrupt – and it’s pretty well understood by everyone involved – so of course, if I hear something like that – please explain.. explain..)  It’s not like I am capable of voting anyway, but I’d sure like to hear perspectives..

It looks like I’m not the only one who is a little leary of pretty boy pena’s party’s dubious history.  His numbers have fallen in recent polls in advance of tonight’s televised debates.  (Let’s hope these debates are better than the last.)

My personal “favorite”, Quadri is still trailing in the dust, but it looks like Lopez has a chance to take the election from Pena (much like it was ‘taken’ from him in 2006 with his narrow defeat..  Lopez is a socialist which is hard for Americans like me to understand – but then again, it’s not my country, and the levels of inequity here are certainly wider than at home – so maybe someone like Lopez can bring some much needed support to the lower classes.

I mean, a lot of what we take for granted in the USA doesn’t exist here, like a decent free public school education.   (Okay – I know critics will argue about the value of an inner city education – but we still provide a free elementary & secondary school education to all our citizens.)  So socialism for the purpose of providing basic services in all areas of Mexico seems pretty reasonable.  (It would help if I could read some primary source stuff – without using translation software, so I would have a better idea of the specifics of AMLO’s ideas.)

I did ask my friend about the student demonstrations for Yo Soy 132.  I guess as an American growing up after the 1960’s – we tend to not too make much of a big deal over student demonstrators – after all – we have the ‘Occupy’ movements going on right now in our own/ other countries – but he was telling me that this is pretty uncommon in Mexico.

** No, I’m not really into politics but I feel like it’s important to try and understand as much as possible about the places (countries) where I am residing.

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