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Posts Tagged ‘stroke’

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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The Core Valve by Medtronic

Medtronic, the makers and financial backers of a recent study on the Core Valve used for percutaneous aortic valve replacement (aka non-surgical valve replacement) released their findings showing the six month mortality data on patients receiving this valve.

This study which was performed using data from European cardiologists (who have been using this technology longer) were unsurprising – with a higher risk of stroke and overall mortality.  Notably, this study was performed on patients deemed to be ‘at high risk’ for surgery, not ineligible for surgery.  As we’ve discussed before, the term ‘high risk’ is open to considerable interpretation.

A total of 996 frail, elderly patients at high risk for heart surgery were  implanted with Medtronic’s CoreValve device, used to treat severe narrowing of  the aortic valve. Mortality rates at one month and six months were 4.5% and  12.8%, respectively. Stroke rates were 2.9% and 3.4%.

Medtronic said the rates  were consistent with previously reported data from national registries in Europe.”

Unfortunately, the general media’s coverage of these findings have been less than straightforward as Bloomberg proclaims in blazing headlines, “Edwards heart valve skirts rib-cracking for a 2.5 billion dollar market.”  That’s a pretty eye-opening headline that manages to avoid mentioning the real issues – longevity and durability.

Another article from business week proclaims, “Heart Valves found safe.”  Safe, I guess is a relative term – if you aren’t one of the 12.8% that died within six months..

Illustration showing the core valve in place

More about Aortic Stenosis and Valve Replacement therapies at Cartagena Surgery:  (you can also find a link to these stories under the TAVI tab on the sidebar.)

Aortic Stenosis as Heinz 57

More patients need surgery

Aortic Stenosis, surgery and the elderly

Aortic stenosis and TAVI

Aortic Stenosis: New Recommendations for TAVI

Transcatheter Valve Therapies: an overview

TAVI and long-term outcomes

Peri-operative outcomes with TAVI

Talking about TAVI/ TAVR with Dr. Kevin Brady

Will Medicare cover TAVI?

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A new study (re-posted below) found that more than 85% of bariatric patients who had pre-operative evaluation before bariatric surgery had significant obstructive sleep apnea.  While the study was small (less than 400 patients), the findings of this study suggest two things:

1.  An evaluation for sleep apnea should be part of routine pre-operative evaluation but ALSO –

given the very high rates of sleep apnea with increasing BMI – and the increased risks of heart attack, pulmonary hypertension and other serious,  life-threatening consequences of untreated sleep apnea –

2.  Increase screening for obstructive sleep apnea in ALL obese patients. (during routine evaluations, and as part of pre-operative evaluation before any surgery requiring general anesthesia.)  [note: #2 is my personal recommendation – not the recommendation of the researchers presenting at this conference.  But as you’ll note below – the preliminary screening questionaire can be done relatively easily, and given the value of findings – additional testing is reasonable even in patients with negative responses to the questionaire.

Due to the strong link between apnea and cardiac events – in our practice, we screened each patient using a series of questions to both the patient and the patient’s significant other (after obtaining patient permission).

To the patient:  Do you snore?  Have you ever been told you snore?  Do you wake up tired, or feel sleepy during the day?

To significant other:  Does the patient snore?  Do you ever hear long pauses between breathing / snoring while the patient is sleeping? Do you ever think that he/she has stopped breathing?

(Then depending on circumstance, in-patient / out-patient – patients were informally screened using pulse oxymetry either in the cath lab or in the intensive care unit.)  This means – we had nurses monitor the patients during sleep:

– Noting each and every time the patient’s oxygen saturation dropped below 92%

– Alterations in heart rate

– Presence of absence of apnea sleeping patterns, snoring etc.

Since our patients were already in the hospital under nursing care (in either the cath lab, or hospital room) the nurses were able to do this easily as part of routine assessment, and monitoring, and there was no extra cost to our patients.

In our case, this information was used for post-surgical management.  After extubation, patients*  were frequently placed on bipap for several hours to reduce atelectasis, and reintubation.  In our at-risk patients, bipap was instituted as part of the sleep routine during their in-patient stay, with a pulmonary medicine referral, and evaluation for home CPAP therapy.  In this way, we were able to avoid expensive/ and time-consuming tests prior to surgery, and still effectively treat our patients. to determine the predictive value of having a spouse tell us, “sometimes I can’t sleep because I am worried he won’t start breathing again” as we’ve heard on multiple occasions.

In our experience, the significant other was best able to provide important diagnostic information.  Unfortunately, we haven’t recorded these findings as part of a research study

* this therapy was used independent of apnea status

Article Re-post: Presentation of a recent abstract at the American Society of Metabolic and Bariatric Surgery in Orlando, Florida

Sleep Test Needed Before Bariatric Surgery

-Charles Bankhead, reporter

ORLANDO  —  Most candidates for bariatric surgery have obstructive sleep apnea (OSA), making a case for polysomnography as a part of the preoperative evaluation of every patient, investigators concluded.
Of 359 patients who had preoperative polysomnography, 86% had positive tests, which showed severe OSA in half of the cases.

The patients had a high prevalence of the sleep disorder across the range of body mass index (BMI) values represented by the patient population, although every patient in the highest BMI category (≥60) tested positive for OSA, as reported here at the American Society of Metabolic and Bariatric Surgery meeting.

“Some people think that only patients in the highest BMI categories should be referred for polysomnography, because they are the patients who are most likely to have obstructive sleep apnea,” Abdul S. Bangura, MD, of Staten Island University Hospital in New York, told MedPage Today.

ActivateCME
 Points to remember


  • Note that this study was published as an abstract and presented at a conference. These data and conclusions should be considered to be preliminary until published in a peer-reviewed journal.
  • Explain that most candidates for bariatric surgery have obstructive sleep apnea (OSA), making a case for polysomnography as a routine part of the preoperative evaluation of every patient.
  • Note that every patient in the highest BMI category (≥60) had a polysomnographic test showing sleep apnea.

“However, our study showed a high prevalence of obstructive sleep apnea in all BMI categories. Because of that, we think polysomnography is justified during the preoperative evaluation of all bariatric surgery patients, and that is the policy at our institution.”

Obesity substantially increases the risk of OSA, and studies have documented a high prevalence of OSA and other sleep-related breathing disorders among patients evaluated for bariatric surgery. Polysomnography remains the gold standard for diagnosis and assessment of OSA, but practices vary with regard to use of the sleep test in the preoperative evaluation of candidates for weight-loss surgery, said Bangura.

Moreover, patients and physicians alike find sleep tests inconvenient, time-consuming, and expensive, he continued.

At his own center, polysomnography is a routine component of the preoperative workup. However, other centers have adopted a selective approach to use of the sleep test, relying on the level of clinical suspicion of OSA to guide decision making.

“Various scoring systems have been used to screen for sleep apnea, but all of them remain controversial,” said Bangura. “There is currently no standard protocol for screening obese patients for OSA.”

To see whether a routine or selective approach to preoperative testing for OSA is more appropriate, Bangura and colleagues retrospectively reviewed records of all patients who had bariatric surgery procedures at their center from 2005 to 2010. They identified 555 patients, including 359 (65%) who underwent polysomnographic evaluations during their preoperative workup.

Investigators used the apnea/hypopnea index (AHI) to categorize apnea severity, defining mild OSA as an AHI score of 5 to 15 events per hour; moderate as a score of 15 to 30; and severe as a score exceeding 30.

Of the 359 patients evaluated for OSA, 309 (86%) had positive tests, including some patients who had positive OSA tests prior to the preoperative evaluation for bariatric surgery. On the basis of AHI scores, 18% of the 359 patients had mild OSA, 17% had moderate OSA, and 51% had severe apnea.

Analysis of OSA prevalence by preoperative BMI showed that the following tested positive for OSA:

  • 34 of 37 (92%) patients with BMI values of 35 to 39.9
  • 178 of 218 (82%) of patients with BMI values of 40 to 49.9
  • 78 of 85 (92%) of patients with BMI values of 50 to 59.9
  • 100% of patients with BMI values of 60 or greater

“Based on these results, we consider routine polysomnography to be an essential part of the preoperative workup for all bariatric patients,” Bangura and colleagues concluded in their poster presentation.

Randomized controlled trials are required to provide evidence of guidelines on routine use of polysomnography as part of the workup for bariatric surgery patients, he said. Given the lack of a reliable prognostic system to predict OSA, the investigators urged consideration of routine polysomnography as part of the preoperative evaluation of all bariatric surgery candidates.

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Now all of my long-term readers should be able to spot the flaws in the logic here. One study, funded by a drug company with results that are at odds with just about every other study ever published – and that’s the one the FDA uses to approve/ expand the indications for stenting? Guess it’s just another ‘easy’ solution to sell to patients / primary care providers who don’t have the time and resources to review the literature themselves.  No surprise, since I am guessing that cardiologists will be placing the majority of these stents..

From HeartWire:
FDA approves expanded indication for carotid stenting
May 6, 2011 | Susan Jeffrey

Adapted from Medscape Medical News—a professional news service of WebMD
Silver Spring, MD – The US Food and Drug Administration announced today it approved an expanded indication for the RX Acculink carotid stent system (Abbott Vascular, Santa Clara, CA) to include patients at standard surgical risk for carotid endarterectomy [1].

Previously, the RX Acculink stent, used in conjunction with Abbott’s Accunet or Emboshield embolic-protection devices, was approved for use only in patients requiring carotid revascularization who were at high surgical risk. These high-risk patients were also required to have a reference vessel diameter ranging from 4.0 mm to 9.0 mm at the target lesion and be symptomatic with a stenosis of the common or internal carotid artery of >50%.

The stent was also previously approved in high-risk patients without neurological symptoms but with a stenosis of the common or internal carotid artery >80%.

In January, the FDA’s Circulatory System Devices Panel voted 7 to 3 in favor of this expanded indication for the system, saying the benefits of carotid stenting in patients at standard risk for adverse events from endarterectomy outweighed the risks. wait – are you sure about that?? because most of the data shows that surgical risk is actually well under 1% – and that’s looking at VA studies involving tens of thousands of patients, with multi-year follow-up..

The panel also voted 6 to 4, with one abstention, in support of the safety of carotid stenting in standard-risk surgical patients and 8 to 2, again with one abstention, in a vote that asked about the effectiveness of therapy in this expanded patient population.

“Expanded access to RX Acculink means patients and their healthcare providers have another option for treating clogged neck arteries,” Christy Foreman, director of the Office of Device Evaluation in the FDA’s Center for Devices and Radiological Health, said in a statement.

The FDA based its approval on the Carotid Revascularization Endarterectomy versus Stenting Trial (CREST), a 10-year study of 2502 symptomatic and asymptomatic patients at 119 clinical sites in the US and Canada, funded by the National Institute of Neurological Disorders and Stroke with supplemental funding by Abbott.

Patients were treated and followed for at least one year. Results of that study, published in the New England Journal of Medicine, showed that patients treated with stenting had a similar combined rate of death, stroke, and MIs those who underwent surgery [2].

Those who underwent surgery, however, had fewer strokes, and those who had stenting had fewer MIs over follow-up. There was also an effect of age, where older patients had fewer events with surgery, while younger patients had slightly fewer events with stenting. Wait a minute – older patients – surgery is actually safer.. but remember, that’s the excuse we received from the beginning – ‘stents are for the frail old people’.. define ‘slightly fewer’ – does that mean ‘not statistically significant’ because that’s what it sounds like. [cartagena surgery]

The FDA advisory panel emphasized the need for additional long-term follow-up information and the importance of the stent’s use in conjunction with an embolic-protection device.

As a condition of the approval, Abbott is required to conduct a postapproval study that will follow new patients treated with the stent system for at least three years to confirm the results identified in CREST.

The postapproval study will also evaluate how patients age 80 years and older respond to treatment, whether treatment success is affected by operator experience, and whether symptomatic and asymptomatic patients have different outcomes.

“The study is consistent with recommendations made by the expert advisory panel,” the FDA statement notes

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As some of you know – I took on the coffee challenge in graduate school after a few stupid comments from classmates over my coffee drinking habit (I like about four cups a day).. So as part of a grad school assignment I reviewed the literature surrounding coffee, and the active ingredients in coffee and it’s kin (cocoa) and wrote about the health benefits of the methylxanthines; theophylline, theobromide, and caffeine.. I talked about the use of theophylline to prevent anoxic injury to the brain and to help restore spontaneous circulation in people after brady/asystolic arrest..
I also debunked some of the common myths surrounding ‘theophylline toxicity’ and it’s unwarrented and tarnished reputation.**

** (check the potassium level, everyone – and know that the effective / therapuetic range is actually 5 to 10 not 10 to 20)

Since then I hae been ardent follower of coffee drinking/ health stories..
– We now know it doesn’t precipitate atrial fibrillation – as demonstrated in several very large studies last year..

– It’s protective against diabetes and pancreatic cancer..

and now, ladies – it appears the health effects extend to a stroke benefit as well.. Now, maybe it isn’t all true – but the next time someone makes a smarmy comment about coffee harming your health – here’s some ammo to fire right back at them..

Here’s some links to the story- which was widely reported, and picked up by AP.

Coffee reduces Stroke

http://news.yahoo.com/s/ap/20110310/ap_on_he_me/us_med_coffee_stroke

http://consumer.healthday.com/Article.asp?AID=650753

LA timesNow – just make sure you haven’t ruined it with 300 calories worth of fat and sugar..

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If you’ve been following the cardiology and vascular surgery journals – then you’ve been bombarded with articles about strokes in the last two days.

The first series has blazing headlines linking the increased rate of strokes in young people with diet soda consumption (excess salt consumption, obesity, poor dietary habits).

The second series of articles discuss the very topics we’ve been discussing here at Cartagena Surgery.. Surgery versus Stenting..  But as people have been asking, are the two related??

Probably not.  The proposed causes of the increased incidence of stroke in people aged 15 – 44 is theorized to be related to increased sodium intake – which in turn causes hypertension.  Hypertension itself may increase the ‘chipping’ effect on plaques in the carotid artery (in people with pre-existing carotid disease)

or may cause strokes themselves by causing blood vessels in the brain to rupture from the increased pressure.  In young people, it is usually the latter.. (because it usually takes a long time to accumulate carotid plaques.) Unfortunately, it’s this younger population that often goes undetected/ untreated or fails to realize the significance of the diagnosis.  Hypertension/ high blood pressure is a serious condition, and aggressive treatment is warrented.. It’s never just high blood pressure.. It’s THE number one cause of kidney failure, the number one cause of heart failure, and a major cause of stroke (just to name a few.)  and it’s usually easily treatable.

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Carotid stenting sounds like a wonderful solution to the layperson.  But the truth is always more complicated.  I’ll talk about it more here to give a better understanding of the disease, diagnosis, and treatment options.

The carotid arteries

The carotid arteries (along with the vertebral arteries) bring blood to the brain. Plaque embolization (or flecks of plaque breaking off diseased or blocked arteries) is one of the main causes of embolic (or non-bleeding) strokes.  In people with blockages in this artery, treating or removing the plaque can prevent stroke.

Today we will talk about screening and diagnosis.. Next time: treatment options.

Detecting Carotid Stenosis:

These blockages can be detected with the use of a carotid doppler (or ultrasound) to listen to the speed of the blood (velocities) in the carotid artery and to visualize blockages.  Some blockages can also be heard on physical exam –  as a bruit (bru-ee) but this is not always a reliable indicator, as the most severe stenoses (or narrowing from plaque) usually don’t have a bruit.

Results are reported as a range – and this decides treatment options.  Generally, in people that have NOT had a stroke – surgical treatment is not advised until the blockage is 70 – 80% blocked.  This is because the risk of stroke increases with the amount of blockage, as the speed of the blood increases to pass through the narrowed space.  (Picture a garden hose, now put your thumb over the end, covering most of it and make the water shoot out – that’s what we mean by increased velocity.)

If you have had a stroke or mini stroke from a plaque breaking off and travelling to the small vessels of the brain, the doctors will usually operate with lesser blockages – because you have already demonstrated a tendency to have pieces break off.

Now this is important – strokes usually happen because of high grade (70 or higher stenosis) not occlusions (or 100% blockages).  That’s because there is more than one vessel bringing blood to the brain – (remember the vertebrals we mentioned earlier..)  Doctors do not undo occlusions because that actually increases the risk of stroke at the time of surgery.

If you have an occlusion – count yourself as lucky that you didn’t have a stroke when it was 99%  and worry about keeping the remaining vessels as clean as possible with medicines.

Screening for Carotid Stenosis:

Currently there are no screening guidelines for asymptomatic individuals.  Since symptomatic means the person has had a stroke or TIA (mini-stroke) knowing when to screen is important.

Generally screening should be done in people at high risk for developing accelerated plaque formation – and in people with vasculopathic disease history (people with a history of plaque or blockages other places.)

High risk for accelerated plaques:

1. Diabetes – diabetes accelerates plaque formation, which is why new guidelines suggest ALL people with Diabetes, regardless of blood cholesterol tests should be on a statin drug (simvastatin, rosuvastatin, lovastatin, atorvastatin, pravastatin)*

2. History of smoking – smoking causes similar effects inside blood vessels as diabetes.  As I explain to patients in the office, it makes plaque form faster by irritating blood vessels and making plaque more likely to stick.  This is also important when we talk about ‘medical management’ of plaque diseases.

Note: ‘Medical Management’ is a term that means exactly that – managing conditions (not curing or fixing) by use of medications.  The disease won’t go away but the thought is that medicines will slow the worsening of the conditioning.

People with history of vasculopathic disease:  these people should be screened because they already have a history of artery blockages – but people don’t always realize that carotid arteries and other arteries are essentially the same highway, so to speak.

This includes:

1. People with a history of Coronary artery disease (CAD) such as people with previous heart stents or bypass surgery.  In fact, one-third of people screened for carotid artery while awaiting bypass surgery (also called CABG) have significant carotid disease or stenosis.

2. People with blockages elsewhere: Renal artery stenosis (kidneys), peripheral artery disease (PAD) aka blockages in the legs, mesenteric artery disease (abdomen).

3. People with an abnormal eye exam or Amarosis fugax – this is basically a small stroke or mini-stroke to the eye.  Sometimes people develop symptoms (amarosis fugax – which is described as a sudden loss of vision, like a shade coming down over your eye).  Other times, the ophthalmologist sees a plaque in the artery to the eye on exam.

I’ll talk about more in my next post – and I am happy to answer condition related questions but not offer medical advice.  My legal eagles have a fit otherwise..

*as I have previously mentioned in Hidden Gem – it is vitally important patients know the generic names of their medications, along with dosages and administration information.

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