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Archive for the ‘Related Medical News & Information’ Category

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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On the heels of a previous post about NAFLD/ NASH (nonalcoholic liver disease) – Medscape just published new treatment guidelines along was part of an on-going series of articles on  fatty liver disease.

While Medscape is free – it does require a subscription to view, so I’ve re-posted the articles (as downloadable pdfs) here for interested readers.  I would also like to encourage people to sign up with Medscape.com on-line.

Guidelines:

Diagnosis and Management of NAFLD: New Guidelines – David A. Johnson

Summary of new guidelines for treatment of fatty liver disease  – Laurie Barclay

However, there are some concerns related to these new guidelines – primarily the recommendations for Vitamin E and other supplements for biopsy-proven NAFLD.  The biggest concerns relate to the availability and purity of these products.  Caution is advised in the use of unregulated over-the-counter supplements since the purity and efficacy of these products may vary widely.

In the ‘Ask the Experts’ readers ask Dr. William F. Balistreri, MD – Is the Prevalence of NASH Really Rising?   In another article, Dr. Balistreri addresses, How Can I Convince My Patients That NASH Is Serious?

As we’ve discussed before, the incidence of fatty liver disease is on par with the expanding obesity epidemic – and histological evidence of liver disease is apparent in over 70% of bariatric surgery patients (at the time of surgery.)

Now doctors are seeing in younger patients – as the more and more kids become obese. In the article [below] by Helwick,  10% of all adolescents in the USA are estimated to have fatty liver disease.

A Fat Kid With a Fatty Liver: Case Challenge – Valerio Nobili, MD; Massimiliano Raponi, MD

Prevalence of NAFLD Increasing Among American Adolescents -Caroline Helwick

Of course, some of this is old news to long-time readers, who read Charlotte Rabl and Guilherme M. Campos’ article, The Impact of Bariatric Surgery on Nonalcoholic Steatohepatitis here at Cartagena Surgery, way back in April 2012 as part of our on-going discussions on bariatric surgery.

This article was just this beginning; with another article published just a few weeks later by Sindu Stephen; Ancha Baranova and Zobair M Younossi.  Their article, Nonalcoholic Fatty Liver Disease and Bariatric Surgery reinforced the idea of bariatric surgery as a reasonable option for obese patients with liver disease.

For everyone looking for information on fatty liver disease, I hope these articles get you started.. Then head over to Medscape for the full library of resources.

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As part of our continuing discussions on Valvular disease, we are talking to Dr. Didier Lapeyre, a French cardiothoracic surgeon who currently resides in Switzerland.

if you look close you can see the valve leaflets

Talking with Dr. Didier Lapeyre, MD

I spent the morning talking to Dr. Didier Lapeyre, a cardiothoracic surgeon (via Skype). It was a fascinating discussion, and opportunity to ‘pick the brain’ of one of cardiac surgery’s elite surgeons and researchers. As we’ve mentioned before, Dr. Lapeyre is the ‘Father of the modern valve” and a true innovator in the field. His developments in artificial heart technology, mechanical valves and assistive devices have changed the field of cardiac surgery immeasurably, and have saved countless lives around the globe, so it was a pleasure and an honor to speak with him.  Since he is such an accomplished surgeon, and has such a wealth of knowledge, we had a lot of talk about.  It’s also too much to talk about in just one post, so I will be breaking into a couple of different discussions since it is such a great opportunity to bring to his many years of knowledge and experience to my readers here – which in itself, is a daunting but certainly worthwhile task. (It’s not everyday that I get to speak with one of the pioneers of the field).

I. Introduction to Dr. Didier Lapeyre

II. The Lapeyre devices and contributions to cardiac surgery

III. Current issues in cardiac valve replacement

IV. The future of valve replacement

But first, an introduction: Dr. Didier Lapeyre, MD, Cardiothoracic surgeon

Dr. Didier has spent the majority of his fifty + years in the field researching and developing valve technology and he is arguably, the expert in this field.  He has developed several heart valves and in addition to the current valve he is developing, holds five patents for these devices.  He also has four other patented artificial heart designs.  He is the Director and CEO of Lapeyre Medical LLC, and the former president and director of medical affairs for Triflo Medical Incorporated[1].

Learned from the best

After graduating from medical school at Claude Bernard University, Alexis Carrel Medical School in Lyon, France in 1957, he completed his general surgical residency at Claude Bernard University before becoming the chief resident in the cardiothoracic surgery program under Dr. Pierre Marion, one of the French pioneers in cardiac surgery in 1967.

Dr. Lapeyre then traveled to Rome, Italy and joined the department of surgery at the School of Medicine where he designed and developed a ventricular assist device for use in cardiovascular research.  He then returned to France in 1972 to work with Dr. Alain Carpenter, who is known as the father of mitral valve repair[2].  During the ten years he worked with Dr. Carpentier, Dr. Lapeyre helped to develop the first totally artificial heart.

Dr. Didier Lapeyre then headed the Aerospatial Total Artificial Heart Program, while he served as an assistance professor at the illustrious Texas Heart Institute.  While serving as a designer and medical officer at the Aerospatial program, he submitted four patents for his developments.

In 1987, he went on to work at another heart valve program, the Dassault – Aviation Heart Valve Program, which was affiliated with Texas Heart Institute.  While this seems like an unlikely partnership between heart surgery and aviation, during this period, Dr. Lapeyre submitted four patent applications for mechanical valves.

In 1996, he became president of Triflo Medical before establishing his own company in 2002, which is dedicated to the design, development and innovation of prosthetic heart valves.  He is currently working on a new artificial valve that addresses the current problems in existing technologies by eliminating the need for anti-coagulation.


[1] Dr. Lapeyre was previously involved in a legal action with this corporation in the ninth circuit court of the United States (central California).  Dr. Lapeyre ultimately won a multi-million dollar countersuit in this action.

[2] In 2005, Dr. Carpentier received the prestigious Medallion of Scientific Achievement from the American Association for Thoracic Surgery (AATS).  It was only the fifth time such an honor was bestowed, and the first time it was awarded to someone outside the United States.  (Other notable recipients include the mega-giants of cardiac surgery, Michael E. Debakey and rival, Denton Cooley.)

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As reported at the heart.org, in an article by Michael R’iodan, a recent study completed in the Netherlands showed a heightened risk of post-operative myocardial infarction (MI or heart attack) in the first few weeks after orthopedic surgery (Hip and knee replacement).  This study showed patients to have an up to a 25X increased risk of heart attack in this post-operative period – the risk was particularly acute in the elderly and in patients with previous diagnosis of cardiac disease.

This highlights the importance of pre-operative screening, aggressive medical management of co-morbid conditions during and after surgery, and detecting the sometimes ‘missed’ post-operative MI.  Patients should be carefully evaluated for the presence of angina, or risk factors contributing to the development of coronary artery disease such as hypertension, hypercholesteremia, peripheral vascular disease or diabetes.

Critical medications such beta blockers and statins should be continued during and after surgery.  Medications such as aspirin should be evaluated (and in many cases) continued.

Studies such as this shouldn’t surprise medical professionals – they just confirm what we already know, and should encourage evidence based practice and careful pre-operative screening and co-morbidity management.

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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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The latest studies suggest that the traditional long-course of antibiotics prior to valve replacement for infective endocarditis may be the wrong approach.  As explained on Medpage, this represents a huge shift for cardiology and cardiac surgery in treatment strategies.

The data showed that waiting until the 4 to 6 week course of antibiotics was completed drastically increased the risk of thromboembolic events, and increased patient mortality.

The EASE study which was published last month in the New England Journal of Medicine by Kang et. al out of South Korea demonstrated a striking difference in outcomes with one patient death in the surgical group versus 9 in the current practice (antibiotic group).  While this study is small in size – the implications are enormous, as infective endocarditis remains alarmingly high, particularly in ‘third world’ or less affluent countries.

In a 2009 paper by Murdoch et. al, the authors discuss the incidence, clinical presentation and outcomes of infective endocarditis in 25 countries.

As a side note, this news comes in the midst of writing about the current developments and limitations in mechanical valve prosthesis here at Cartagena Surgery with input from experts in the field.. Look for updates soon.

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Busy day yesterday – spent the morning shift with Jose Luis Barron over at Mexicali General..  Then raced over to Hospital de la Familia for a couple of general and bariatric cases.

The first case was with the ever charming Drs. Horatio Ham, and Rafael Abril (who we’ve talked about before.)  with the always competent Dr. Campa as the anesthesiologist.   (Seriously – Dr. Campa always does an excellent job.)

Then as we prepared to enter the second case – the director of the hospital asked if I would like to meet Dr. Marco Sarinana G. and his partner, Dr. Joel Ramos..  well, of course.. (Dr. Sarinana’s name has a tilde over the first n – but try coaxing that out this antique keyboard..)

So off to the operating room with these three fellows.  (This isn’t my usual protocol for interviewing surgeons, etc. but sometimes it works out this way.)  Their practice is called Mexicali Obesity Solutions.

Dr. Marco Sarinana and Dr. Joel Ramos, Bariatric surgeons

Dr. Alejandro Ballesteros was the anesthesiologist for the case – and everything proceeded nicely.

After that – it was evening, and time to write everything down!

Today should be another great day – heading to IMSS with Dr. Gabriel Ramos for a big case..

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