Pierre Bedard

Very Long-Term Survival Implications of Heart Valve Replacement With Tissue Versus Mechanical Prostheses in Adults <60 Years of Age

Background— Several centers favor replacing a diseased native heart valve with a tissue rather than a mechanical prosthesis, even in younger adult patients. However, long-term data supporting this approach are lacking. We examined the survival implications of selecting a tissue versus a mechanical prosthesis at initial left-heart valve replacement in a cohort of adults <60 years of age who were followed for over 20 years. Methods and Results— Comorbid and procedural data were available from 6554 patients who underwent valve replacement at our institution over the last 35 years. Of these, 1512 patients contributed follow-up data beyond 20 years, of whom 567 were adults <60 years of age at first left-heart valve operation (mean survivor follow-up, 24.0±3.1 years). Late outcomes were examined with Cox regression. Valve reoperation, often for prostheses that are no longer commercially available, occurred in 89% and 84% of patients by 20 years after tissue aortic and mitral valve replacement, respectively, and was associated with a mortality of 4.3%. There was no survival difference between patients implanted with a tissue versus a mechanical prosthesis at initial aortic valve replacement (hazard ratio 0.95; 95% CI: 0.7, 1.3; P=0.7). For mitral valve replacement patients, long-term survival was poorer than after aortic valve replacement (hazard ratio 1.4; 95% CI: 1.1, 1.8; P=0.003), but again no detrimental effect was associated with use of a tissue versus a mechanical prosthesis (hazard ratio 0.9; 95% CI 0.5, 1.4; P=0.5). Conclusions— In our experience, selecting a tissue prosthesis at initial operation in younger adults does not negatively impact survival into the third decade of follow-up, despite the risk of reoperation.

Gender differences in the long-term outcomes after valve replacement surgery

Objective: To compare the long-term outcomes in women and men after valve replacement surgery. Design: Observational study. Setting: Postoperative aortic valve replacement (AVR) or mitral valve replacement (MVR). Patients: 3118 patients (1261 women, 1857 men) who underwent AVR or MVR between 1976 and 2006 (2255 AVR, 863 MVR), with mean follow-up of 5.6 (4.5) years. Main outcome measures: The independent effect of gender on the risk of long-term complications (reoperation, stroke and death) after valve replacement surgery using multivariate actuarial methods. Results: After implantation of an aortic valve bioprosthesis, women had a significantly lower rate of reoperation compared to men (comorbidity-adjusted hazard ratio (HR) 0.4; 95% confidence intervals (CI) 0.2 to 0.9). In contrast, if an aortic mechanical prosthesis had been implanted, women were more at risk for late stroke compared to men (HR 1.7; CI 1.1 to 2.7). After adjustment for age and co-morbidities, women had significantly better long-term survival compared to men after bioprosthetic AVR (HR 0.5; CI 0.3 to 0.6), but there was no survival difference between genders after mechanical AVR. Trends existed towards better survival for women after bioprosthetic MVR (HR 0.6; CI 0.4 to 1.0) and mechanical MVR (HR 0.8; CI 0.5 to 1.1). Conclusion: The long-term outcomes after valve replacement surgery differ between women and men. Although women have more late strokes after valve replacement, they undergo fewer reoperations and have better overall long-term survival compared to men.

Comparison of accuracy of transesophageal versus transthoracic echocardiography for the detection of mitral valve prolapse with ruptured chordae tendineae (flail mitral leaflet)

The accuracy of transesophageal echocardiography was compared with that of transthoracic echocardiography in the detection of ruptured chordae tendineae (flail mitral leaflet) in 27 patients with mitral valve prolapse (MVP) who underwent valve repair or replacement for mitral regurgitation. Confirmation of the presence of ruptured chordae resulting in a flail leaflet was available at surgery in all cases. The echocardiographic studies were read blindly by 2 independent observers with any differences resolved by a third. Mean (+/- standard deviation) age was 63 +/- 13 years. Men (n = 20) outnumbered women (n = 7) (p less than 0.02), and tended to be younger (p = 0.06). Flail leaflets were identified in 20 of 27 patients. In 1 patient, both leaflets were involved and in the remaining 19 patients posterior leaflets (15 patients) were more frequently affected than anterior leaflets (4 patients). Transesophageal echocardiography correctly identified all 20 patients with flail leaflets, but 1 false positive study occurred among the 7 patients without a flail leaflet. In contrast, transthoracic echocardiography identified only 12 of 20 patients with flail leaflets, with no false positive studies. Transesophageal echocardiography was more accurate, correctly classifying 26 of 27 (96%) cases versus 19 of 27 (70%) by the transthoracic approach (p less than 0.01). This study suggests a higher incidence of chordal rupture to the posterior leaflet in patients with MVP and demonstrates improved accuracy of transesophageal over transthoracic echocardiography in the detection of flail leaflets.

Experience with Emergency Aortocoronary Bypass Grafts in the Presence of Acute Myocardial Infarction

In the past 18 months 15 patients have undergone emergency aortocoronary bypass grafts using saphenous vein in the presence of acute myocardial infarction. Eight patients were in a state of cardiogenic shock, and seven patients were having severe cardiac arrhythmias, persistent hypotension, or signs of extending infarction. There were three operative deaths, all of which occurred in the cardiogenic shock group of patients. One patient died three months after operation of a cerebrovascular accident. There are 11 surviving patients. One patient presently has angina, and one patient shows signs of left heart failure. The remaining patients are well at the present time. We feel that angiography and surgery early in the course of a complicated myocardial infarct should diminish the immediate risk of death from both pump failure and cardiac rupture. Controlled prospective studies are required to elucidate the timing and indications for operation.

Causes of death in aortocoronary bypass surgery: experience with 1,000 patients.

Of the first 1,000 consecutive patients in our unit to receive aortocoronary bypass grafts, 108 have died: 32 at operation, 16 in hospital, and 60 late. Of 343 patients who had a normal ventricle, only 1 (0.29%) died at operation, and 2 of the 8 late deaths were noncardiac in cause. Most operative deaths resulted from low cardiac output, and most later deaths were caused by congestive heart failure. A study of the relation of various clinical and operative factors with mortality found that patients with congestive heart failure who underwent valve replacement and bypass grafting had the worst prognosis (73% mortality) while those undergoing bypass grafting with Class III or IV ventricular function (as we define it) and congestive heart failure were next (49% mortality).

Compression of anomalous circumflex coronary artery by a prosthetic valve ring.

Anomalous origin of the circumflex coronary artery from the right aortic sinus, with a retroaortic course, is usually without consequence. We report a patient who underwent aortic valve replacement for bicuspid aortic valve. The prosthesis sewing ring distorted the circumflex, producing myocardial infarcts and sudden death during exercise.

Submammary Skin Incision as a Cosmetic Approach to Median Sternotomy

Median sternotomy is the incision of choice to allow access to the anterior mediastinum, heart, or both lungs. The vertical skin incision leaves an unsightly scar for many female patients. A bilateral submammary horizontal skin incision with dissection of a flap including the subcutaneous tissue and breasts allows exposure of the sternum so that a median sternotomy can be performed. Since November 1981, we have used this incision 40 times in female patients undergoing open heart surgery. The exposure of the mediastinum was excellent, and there were no difficulties in cannulating the ascending aorta for cardiopulmonary bypass. Complications associated with this incision are insignificant if close attention is paid to details.

Uterine tumor in the heart: Intravenous leiomyomatosis

INTRAVENOUS LEIOMYOMATOSIS OF THE UTERUS is a rare clinical enti ty cha rac t e r i zed by in t r avenous ex t ens ion o f a s m o o t h musc le t u m o r o r ig ina t ing in the uterus. Earliest r epo r t s o f this c o n d i t i o n da te back to the b e g i n n i n g o f this century. 1 Occasional ly these t umor s do n o t b e c o m e symptomat i c be fo r e e x t e n d i n g in to t he hear t . We p r e s e n t o n e such case and a review o f the l i te ra ture o f in t ravenous l e iomyomatos i s with cardiac ex tens ion . A discussion o f the d iagnos is a n d surgical t r e a t m e n t o f this les ion is p r e s e n t e d .

Resection of right atrial tumor thrombi without circulatory arrest

Resectable retroperitoneal tumors with right atrial tumor thrombus extension have been excised previously using cardiopulmonary bypass and deep hypothermic circulatory arrest. We have used a technique involving clamping of the descending aorta with avoidance of deep hypothermic circulatory arrest in 6 patients. The approach provided a virtually bloodless field and allowed complete resection to be performed with low morbidity.

Postoperative lipid-lowering therapy and bioprosthesis structural valve deterioration: justification for a randomised trial?

OBJECTIVE Bioprosthesis structural valve deterioration (SVD) is an incompletely understood process involving the accumulation of calcium and lipids. Whether this process could be delayed with lipid-lowering therapy (LLT) is currently unknown. The purpose of this observational study was to evaluate if an association exists between early LLT and a slowing of bioprosthesis SVD, with a view to designing a prospective trial. METHODS We followed 1193 patients who underwent aortic valve replacement with contemporary bioprostheses between 1990 and 2006 (mean follow-up 4.5+/-3.1 years, maximum 17.3 years). Of these patients, 150 received LLT (including statins) early after surgery. Prosthetic valve haemodynamics on echocardiography and freedom from re-operation for SVD were compared between patients who did and did not receive postoperative LLT. RESULTS After bioprosthetic implantation, the progression of peak and mean trans-prosthetic gradients during echocardiographic follow-up (mean 3.3 years) was equivalent between patients treated with and without LLT (peak increase: 0.9+/-7.7 vs 1.1+/-10.9 mmHg, LLT vs no LLT, P=0.87; mean increase: 0.8+/-4.1 vs 0.2+/-5.9 mmHg, LLT vs no LLT, P=0.38). The annualised linear rate of gradient progression following valve replacement was also similar between groups (peak increase per year: 2.0+/-12.1 vs 1.0+/-12.9 mmHg per year, LLT vs no LLT, P=0.52; mean increase per year: 0.5+/-2.2 vs 0.6+/-6.0 mmHg per year, LLT vs no LLT, P=0.94). The incidence of mild or greater aortic insufficiency on the most recent echocardiogram was comparable (16.3% vs 13.8%, LLT vs no LLT, P=0.44), and there was no difference in the 10-year freedom from re-operation for SVD between the two groups [98.9% (95% confidence interval (CI): 91.9%, 99.8%) vs 95.4% (95% CI 90.5%, 97.9%), LLT vs no LLT, P=0.72]. CONCLUSIONS In this observational study, there was no association demonstrated between early postoperative LLT and a slowing of bioprosthesis SVD. With the excellent durability of bioprostheses in the current era, a prospective randomised trial of statin therapy to prevent bioprosthetic SVD does not appear to be justified, let alone feasible.