Yves Hébert

Increased incidence of acute ascending aortic dissection with off-pump aortocoronary bypass surgery?

BACKGROUND An apparent increase in the incidence of acute ascending aortic dissection following off-pump coronary artery bypass grafting (OPCAB) led us to assess retrospectively the rate and circumstances of this complication in our institution on a consecutive series of patients undergoing aortocoronary bypass performed with and without extracorporeal circulation (ECC). METHODS A retrospective analysis of acute ascending aortic dissections complicating coronary artery bypass grafting surgery in 3,031 patients in our institution since April 1, 1995, was performed using the database of the Montreal Heart Institute. RESULTS There was a greater frequency of hypertension in the OPCAB group. Iatrogenic acute aortic dissection occurred in 3 patients among 308 operated on without ECC (0.97%) and 1 patient among 2,723 operated on under ECC (0.04%). This difference was statistically significant (p < 0.00001). CONCLUSIONS The risk of aortic dissection may be increased in OPCAB. Careful manipulation of the aorta with a single side-clamping and a control of the arterial pressure should be used to minimize aortic trauma. High-risk patients should undergo CABG without side-clamping of the aorta or CABG with ECC to prevent this redoubtable complication of myocardial revascularization.

Immediate and long-term results of valve replacement for native and prosthetic valve endocarditis

BACKGROUND The objective of the present study was to compare current results of prosthetic valve replacement following acute infective native valve endocarditis (NVE) with that of prosthetic valve endocarditis (PVE). Prosthetic valve replacement is often necessary for acute infective endocarditis. Although valve repair and homografts have been associated with excellent outcome, homograft availability and the importance of valvular destruction often dictate prosthetic valve replacement in patients with acute bacterial endocarditis. METHODS A retrospective analysis of the experience with prosthetic valve replacement following acute NVE and PVE between 1988 and 1998 was performed at the Montreal Heart Institute. RESULTS Seventy-seven patients (57 men and 20 women, mean age 48 +/- 16 years) with acute infective endocarditis underwent valve replacement. Fifty patients had NVE and 27 had PVE. Four patients (8%) with NVE died within 30 days of operation and there were no hospital deaths in patients with PVE. Survival at 1, 5, and 7 years averaged 80% +/- 6%, 76% +/- 6%, and 76% +/- 6% for NVE and 70% +/- 9%, 59% +/- 10%, and 55% +/- 10% for PVE, respectively (p = 0.15). Reoperation-free survival at 1, 5, and 7 years averaged 80% +/- 6%, 76% +/- 6%, and 76% +/- 6% for NVE and 45% +/- 10%, 40% +/- 10%, and 36% +/- 9% for PVE (p = 0.003). Five-year survival for NVE averaged 75% +/- 9% following aortic valve replacement and 79% +/- 9% following mitral valve replacement. Five-year survival for PVE averaged 66% +/- 12% following aortic valve replacement and 43% +/- 19% following mitral valve replacement (p = 0.75). Nine patients underwent reoperation during follow-up: indications were prosthesis infection in 4 patients (3 mitral, 1 aortic), dehiscence of mitral prosthesis in 3, and dehiscence of aortic prosthesis in 2. CONCLUSIONS Prosthetic valve replacement for NVE resulted in good long-term patient survival with a minimal risk of reoperation compared with patients who underwent valve replacement for PVE. In patients with PVE, those who needed reoperation had recurrent endocarditis or noninfectious periprosthetic dehiscence.

Tricuspid valve replacement: an analysis of 25 years of experience at a single center

BACKGROUND Tricuspid valve replacement is seldom used in clinical practice, but the choice between mechanical and biologic prostheses remains controversial. METHODS Between 1977 and 2002, 97 patients underwent tricuspid valve replacement and were followed at the Montreal Heart Institute Valve Clinic. Patients underwent replacement with bioprostheses (n = 82) and mechanical valves (n = 15). RESULTS Patients with bioprosthetic tricuspid replacements averaged 53 +/- 13 years of age compared with 48 +/- 11 years in those with tricuspid mechanical valve replacements (p = 0.2). Isolated tricuspid valve replacement was performed in 11 patients (73%) in the mechanical valve group compared with 31 patients (38%. p = 0.01) in the bioprosthetic replacement group. In patients undergoing bioprosthetic tricuspid replacement, 51 (62%) underwent multiple associated valve replacements. The 5-year survival after tricuspid replacement averaged 60% +/- 13% in the mechanical valve group and 56% +/- 6% in the biologic replacement group (p = 0.8). The 5-year freedom rate from tricuspid valve reoperation averaged 91% +/- 9% in patients with mechanical valves and 97% +/- 3% in those with biologic valves (p = 0.2). CONCLUSIONS; Patient survival after tricuspid valve replacement is suboptimal but related to the clinical condition at operation. The use of biologic prostheses for tricuspid valve replacement remains a good option in young patients because of limited life expectancy unrelated to the type of tricuspid prostheses at long-term follow-up.

Retrospective cohort analysis of 926 tricuspid valve surgeries: Clinical and hemodynamic outcomes with propensity score analysis

BACKGROUND The objectives were to describe morbidity and mortality after tricuspid valve (TV) surgery, to compare outcomes after repair versus replacement, and to assess risk factors for mortality and tricuspid regurgitation (TR) recurrence. METHODS A retrospective cohort study including 926 consecutive cases of TV surgery (792 repairs and 134 replacements) performed at the Montreal Heart Institute was conducted. Median follow-up was 4.3 years (4,657 patient-years). Median age was 62 years (interquartile range 53-69 years), and 72% of patients were women. RESULTS Operative mortality was 14% (128 patients: 1977-1998 20%, 1999-2008 7%, P < .001). Independent risk factors for operative mortality in the 1999 to 2008 period were hypertension (odds ratio [OR] 6.03, P = .02), daily furosemide dose (by 10 mg) (OR 1.06, P = .05), weight (by 10 kg) (OR 0.36, P < .01), and cardiopulmonary bypass time (by 10 minutes) (OR 1.29, P < .001). Ten-year survival was 49% ± 2% and 38 ± 5% in the repair and replacement groups, respectively (P = .012). At discharge, severity of TR was ≥3/4 in 13% and 2% of patients in the repair and replacement groups, respectively (P = .01). Propensity score analysis showed that tricuspid repair was associated with higher rates of TR ≥3/4 at follow-up compared with replacement (hazard ratio 2.15, P = .02). Forty-eight reoperations (7% of patients at risk) were performed during follow-up (repair group, 6%; replacement group, 15%; P = .01). At last follow-up, New York Heart Association functional class was improved compared with baseline in both groups (P < .001). CONCLUSION Tricuspid valve surgery is associated with substantial early and late mortalities but with significant functional improvement. Replacement is more effective in early and late corrections of regurgitation, but it does not translate into better survival outcomes.

Experience with the 19-mm Carpentier-Edwards pericardial bioprosthesis in the elderly

BACKGROUND Valve replacement in small aortic root remains a surgical challenge. The objective of this study was to compare results of the 19-mm bioprosthesis with those of larger prostheses in the elderly. METHODS The 443 patients, 70 years of age and older, who underwent aortic valve replacement with Carpentier-Edwards pericardial bioprostheses were reviewed. RESULTS There were 93 patients with a mean age of 76+/-4 years with implantation of 19-mm prostheses and 350 patients with a mean age of 75+/-4 years with larger bioprostheses. Associated aortoplasty was performed in 10 patients (11%) with 19-mm bioprostheses and in 8 patients (2%) with larger bioprostheses (p = 0.001). There were 11 deaths (12%) within 30 days of surgery in patients with 19-mm prostheses and 22 deaths (6%) among those with larger prostheses (p = 0.1). The 7-year survival rate averaged 61%+/-7% in patients with 19-mm prostheses and 67%+/-4% in those with larger prostheses (p = 0.8). The 7-year freedom rates from all valve-related events averaged 96%+/-2% and 93%+/-2%, respectively (p = 0.6). CONCLUSIONS Aortic valve replacement with the 19-mm Carpentier-Edwards pericardial bioprosthesis offers excellent midterm results in the elderly.

Early reoperation for iatrogenic left main stenosis after aortic valve replacement: a perilous situation.

BACKGROUND Iatrogenic left main coronary artery (LMCA) stenosis secondary to direct ostial cannulation during aortic valve replacement still occurs and is a morbid situation due to the difficulties of early reoperation and in providing adequate myocardial protection. METHODS A retrospective analysis was performed and identified seven patients with an iatrogenic LMCA stenosis, after 2158 aortic valve replacements (AVR) (0.3%) in our institution since 1987. RESULTS All patients with LMCA stenosis after AVR had undergone direct ostial cannulation with self-inflating balloon cannulas at the time of AVR. At reoperation for LMCA stenosis, severe ischemia developed in one patient and injury to cardiac structures occurred in four patients. Four patients suffered a perioperative myocardial infarction and congestive heart failure developed in two patients at late follow-up. CONCLUSIONS LMCA stenosis following coronary ostial cannulation at the time of AVR is a rare yet morbid complication. Reoperation for this condition is fraught with a high operative morbidity rate and poor long-term outcome. Prevention of this complication is quintessential, avoiding ostial cannulation with self-inflating balloons.

Long-Term Results With Triple Valve Surgery

BACKGROUND Whether to use biological or mechanical prostheses and whether to repair or replace the tricuspid valve during primary and reoperative triple valve surgery remains controversial. The objective of the present study was to review our experience with primary and reoperative triple valve surgery using CarboMedics (CM) and Carpentier-Edwards (C-E) heart valves. METHODS All 73 patients undergoing triple valve surgery since 1982 were prospectively followed at the Montreal Heart Institute valve clinic. Aortic valve replacement was performed with CM prostheses (57 patients) and with C-E prostheses (16 patients). Mitral valve replacement was performed with mechanical prostheses (56 patients) and with biological valves (14 patients). Mitral valve repair was done in 3 patients. Tricuspid valve annuloplasty or commissurotomy or both were performed in 66 patients and the tricuspid valve was replaced in 7 patients. Patient survival, complications, and the type of valve procedures were analyzed. RESULTS Thirty patients averaging 62+/-10 years of age underwent primary triple valve surgery and 43 patients averaging 60+/-10 years of age underwent reoperative triple valve surgery (p = 0.5). Tricuspid repair consisted of annuloplasty with the Bex linear reducer (n = 47), the C-E ring (n = 13), or the De Vega technique (n = 5). Tricuspid valve replacement was done using the C-E pericardial prostheses. The 30-day mortality was 17% and 12% in patients with primary and reoperative surgery, respectively (p = 0.5) and patient survival averaged 80%+/-7%, 75%+/-8%, and 41%+/-15%, and 70%+/-7%, 57%+/-9%, and 50%+/-10%, respectively 1, 5, and 10 years following surgery (p = 0.5). The freedom rate from thromboembolism and from bleeding complications were 87%+/-6% and 95%+/-3% in primary and reoperative patients, respectively, 5 years following surgery. CONCLUSIONS Triple valve surgery, either as a primary or a reoperative procedure, results in acceptable long-term survival with both mechanical and biological prostheses.

Comparison of long-term clinical results of double versus single internal mammary artery bypass grafting

BACKGROUND The long-term benefits of double versus single internal mammary artery (IMA) coronary bypass grafting have not yet been established. METHODS Six hundred patients were studied retrospectively 10 years after coronary revascularization using saphenous vein grafts (SVGs) only or single or double IMA grafts. RESULTS Patients with double IMA grafts were younger and were more likely to have diabetes, left main coronary stenosis, and three-vessel coronary artery disease than patients with SVGs or single IMA grafts. Patients with SVGs and double IMA grafts had a greater number of diseased coronary vessels and a greater number of coronary bypass grafts per patient than patients with single IMA grafts (mean +/- SEM, 2.8 +/- 1.0, 2.8 +/- 0.7, 2.1 +/- 0.8 grafts per patient, respectively, p < 0.0001). Actuarial survival rates 10 years after placement of SVGs and single and double IMA grafts averaged 83% +/- 6%, 90% +/- 4%, and 87% +/- 8%, respectively (p = 0.03). Cox regression analysis showed that diabetes (relative risk, 2.03; 95% confidence interval, 1.55 to 2.66) and chronic pulmonary obstructive disease (relative risk, 2.20; 95% confidence interval, 1.58 to 3.80) increased, whereas an IMA graft on the left anterior descending coronary artery significantly decreased, the risk of death after operation (relative risk, 0.45; 95% confidence interval, 0.36 to 0.57) throughout the follow-up period. CONCLUSIONS Use of an IMA graft on the left anterior descending coronary artery improves survival compared with use of an SVG. Although patients with double IMA grafts had a greater number of poor prognosis risk factors before operation, their 10-year survival rate was similar to that of patients with a single IMA graft.

Aortic valve replacement with mechanical and biologic prostheses in middle-aged patients

Abstract Background . Mechanical prostheses are used in young patients and bioprostheses in the elderly because of the higher rate of structural failure of bioprostheses. The objective of the present study was to compare results after aortic valve replacement with mechanical (CarboMedics) and biologic (Carpentier-Edwards pericardial) in middle-aged patients. Methods . Five hundred twenty-one patients, aged between 55 and 65 years, who underwent aortic valve replacement with mechanical (n = 363) or biologic (n = 158) prostheses were reviewed. Results . The 10-year actuarial survival rate averaged 66% ± 6% in patients implanted with mechanical valves compared with 75% ± 4% in patients implanted with biologic valves ( p = 0.2). The 10-year freedom rate from thromboembolism, hemorrhage, and endocarditis averaged 92% ± 7%, 97% ± 2%, and 99% ± 1%, respectively, in patients with mechanical valves compared with 91% ± 3% ( p = 0.03), 99% ± 1% ( p = 0.4), and 95% ± 2% ( p = 0.01), respectively, in those with biologic valves. The 10-year freedom rate from all valve-related complications averaged 90% ± 7% and 83% ± 4%, respectively ( p = 0.01). Conclusions . The freedom rate from all valve-related complications was higher among patients with mechanical valves compared with biologic valves 10 years after aortic valve replacement in middle-aged patients.

Massive gastrointestinal hemorrhage after transoesophageal echocardiography probe insertion

PurposeTo describe a case of a massive gastric bleeding following emergency coronary artery bypass surgery associated with transoesophageal echocardiographic (TEE) examination.Clinical featuresA 50-yr-old man was referred for an acute myocardial infarction and pulmonary edema (Killip class 3). Twelve hours after his myocardial infarction, he was still having chest pain despite aniv heparin infusion. Coronary angiography revealed severe three-vessel disease with multifocal stenosis of the left anterior descending, circumflex and total occlusion of the right coronary artery. The patient was transferred to the operating room for emergency coronary artery bypass graft surgery. After total systemic heparinization (3 mg·kg−1) was obtained for cardiopulmonary bypass, a multiplane TEE probe was inserted without difficulty to monitor myocardial contractility during weaning from CPB. During sternal closure, the TEE probe was removed and an orogastric tube was inserted with immediate drainage of 1,200 ml red blood. Endoscopic examination demonstrated a mucosal tear near the gastro-oesophageal junction and multiple erosions were seen in the oesophagus. These lesions were succesfully treated with submucosal epinephrine injections and the patient was discharged from the hospital eight days after surgery.ConclusionThis is a report of severe gastrointestinal hemorrhage following TEE examination in a fully heparinized patient. This incident suggest that, if the use of TEE is expected, the probe should preferably be inserted before the administration of heparin and the beginning of CPB.RésuméObjectifDécrire un cas de gastrorragie survenue après un pontage aortocoronarien et associée à un examen par échocardiographie transoesophagienne (ETO).Aspects cliniquesUn homme de 50 ans a été admis à l’hôpital pour un infarctus aigu du myocarde et un oedème pulmonaire (classification de Killip : 3). Douze heures après l’infarctus, il éprouvait toujours des douleurs thoraciques malgré une perfusion intraveineuse d’héparine. La coronarographie a montré une maladie tritronculaire sévère qui se manifestait par une sténose multifocale de l’artère interventriculaire antérieure, de l’artère auriculo-ventriculaire et l’occlusion totale de l’artère coronaire droite. Le patient a été transporté à la salle d’opération pour un pontage aortocoronarien d’urgence. Après que l’héparinisation générale totale (3 mg·kg−1) a été obtenue pour la circulation extracorporelle, une sonde d’ETO multiplan a été facilement introduite pour contrôler la contractilité du myocarde pendant le sevrage de la CEC. Pendant la fermeture stemale, on a retiré la sonde d’ETO et on a inséré un tube orogastrique pour un drainage immédiat de 1200 ml de sang rouge. Lexamen endoscopique a démontré une dilacération près de la jonction oeso-gastrique et de multiples érosions ont été visualisées dans l’oesophage. Ces lésions ont été traitées avec succès par des injections sous-muqueuses d’épinéphrine et le patient a quitté l’hôpital huit jours après la chirurgie.ConclusionNous avons rapporté le cas d’une hémorragie gastro-intestinale sévère survenu à la suite d’une ETO chez un patient complètement héparinisé. Cet incident permet de présumer que, dans le cas où on pense utiliser l’ETO, la sonde devrait, de préférence, être introduite avant l’administration d’héparine et le début de la CEC.