Pierre Voisine

Mitral-Valve Repair versus Replacement for Severe Ischemic Mitral Regurgitation

BACKGROUND Ischemic mitral regurgitation is associated with a substantial risk of death. Practice guidelines recommend surgery for patients with a severe form of this condition but acknowledge that the supporting evidence for repair or replacement is limited. METHODS We randomly assigned 251 patients with severe ischemic mitral regurgitation to undergo either mitral-valve repair or chordal-sparing replacement in order to evaluate efficacy and safety. The primary end point was the left ventricular end-systolic volume index (LVESVI) at 12 months, as assessed with the use of a Wilcoxon rank-sum test in which deaths were categorized below the lowest LVESVI rank. RESULTS At 12 months, the mean LVESVI among surviving patients was 54.6±25.0 ml per square meter of body-surface area in the repair group and 60.7±31.5 ml per square meter in the replacement group (mean change from baseline, -6.6 and -6.8 ml per square meter, respectively). The rate of death was 14.3% in the repair group and 17.6% in the replacement group (hazard ratio with repair, 0.79; 95% confidence interval, 0.42 to 1.47; P=0.45 by the log-rank test). There was no significant between-group difference in LVESVI after adjustment for death (z score, 1.33; P=0.18). The rate of moderate or severe recurrence of mitral regurgitation at 12 months was higher in the repair group than in the replacement group (32.6% vs. 2.3%, P<0.001). There were no significant between-group differences in the rate of a composite of major adverse cardiac or cerebrovascular events, in functional status, or in quality of life at 12 months. CONCLUSIONS We observed no significant difference in left ventricular reverse remodeling or survival at 12 months between patients who underwent mitral-valve repair and those who underwent mitral-valve replacement. Replacement provided a more durable correction of mitral regurgitation, but there was no significant between-group difference in clinical outcomes. (Funded by the National Institutes of Health and the Canadian Institutes of Health; ClinicalTrials.gov number, NCT00807040.).

Two-Year Outcomes of Surgical Treatment of Severe Ischemic Mitral Regurgitation

BACKGROUND In a trial comparing coronary-artery bypass grafting (CABG) alone with CABG plus mitral-valve repair in patients with moderate ischemic mitral regurgitation, we found no significant difference in the left ventricular end-systolic volume index (LVESVI) or survival after 1 year. Concomitant mitral-valve repair was associated with a reduced prevalence of moderate or severe mitral regurgitation, but patients had more adverse events. We now report 2-year outcomes. METHODS We randomly assigned 301 patients to undergo either CABG alone or the combined procedure. Patients were followed for 2 years for clinical and echocardiographic outcomes. RESULTS At 2 years, the mean (±SD) LVESVI was 41.2±20.0 ml per square meter of body-surface area in the CABG-alone group and 43.2±20.6 ml per square meter in the combined-procedure group (mean improvement over baseline, -14.1 ml per square meter and -14.6 ml per square meter, respectively). The rate of death was 10.6% in the CABG-alone group and 10.0% in the combined-procedure group (hazard ratio in the combined-procedure group, 0.90; 95% confidence interval, 0.45 to 1.83; P=0.78). There was no significant between-group difference in the rank-based assessment of the LVESVI (including death) at 2 years (z score, 0.38; P=0.71). The 2-year rate of moderate or severe residual mitral regurgitation was higher in the CABG-alone group than in the combined-procedure group (32.3% vs. 11.2%, P<0.001). Overall rates of hospital readmission and serious adverse events were similar in the two groups, but neurologic events and supraventricular arrhythmias remained more frequent in the combined-procedure group. CONCLUSIONS In patients with moderate ischemic mitral regurgitation undergoing CABG, the addition of mitral-valve repair did not lead to significant differences in left ventricular reverse remodeling at 2 years. Mitral-valve repair provided a more durable correction of mitral regurgitation but did not significantly improve survival or reduce overall adverse events or readmissions and was associated with an early hazard of increased neurologic events and supraventricular arrhythmias. (Funded by the National Institutes of Health and Canadian Institutes of Health Research; ClinicalTrials.gov number, NCT00806988.).

Surgical treatment of moderate ischemic mitral regurgitation.

BACKGROUND Ischemic mitral regurgitation is associated with increased mortality and morbidity. For surgical patients with moderate regurgitation, the benefits of adding mitral-valve repair to coronary-artery bypass grafting (CABG) are uncertain. METHODS We randomly assigned 301 patients with moderate ischemic mitral regurgitation to CABG alone or CABG plus mitral-valve repair (combined procedure). The primary end point was the left ventricular end-systolic volume index (LVESVI), a measure of left ventricular remodeling, at 1 year. This end point was assessed with the use of a Wilcoxon rank-sum test in which deaths were categorized as the lowest LVESVI rank. RESULTS At 1 year, the mean LVESVI among surviving patients was 46.1±22.4 ml per square meter of body-surface area in the CABG-alone group and 49.6±31.5 ml per square meter in the combined-procedure group (mean change from baseline, -9.4 and -9.3 ml per square meter, respectively). The rate of death was 6.7% in the combined-procedure group and 7.3% in the CABG-alone group (hazard ratio with mitral-valve repair, 0.90; 95% confidence interval, 0.38 to 2.12; P=0.81). The rank-based assessment of LVESVI at 1 year (incorporating deaths) showed no significant between-group difference (z score, 0.50; P=0.61). The addition of mitral-valve repair was associated with a longer bypass time (P<0.001), a longer hospital stay after surgery (P=0.002), and more neurologic events (P=0.03). Moderate or severe mitral regurgitation was less common in the combined-procedure group than in the CABG-alone group (11.2% vs. 31.0%, P<0.001). There were no significant between-group differences in major adverse cardiac or cerebrovascular events, deaths, readmissions, functional status, or quality of life at 1 year. CONCLUSIONS In patients with moderate ischemic mitral regurgitation, the addition of mitral-valve repair to CABG did not result in a higher degree of left ventricular reverse remodeling. Mitral-valve repair was associated with a reduced prevalence of moderate or severe mitral regurgitation but an increased number of untoward events. Thus, at 1 year, this trial did not show a clinically meaningful advantage of adding mitral-valve repair to CABG. Longer-term follow-up may determine whether the lower prevalence of mitral regurgitation translates into a net clinical benefit. (Funded by the National Institutes of Health and the Canadian Institutes of Health Research; ClinicalTrials.gov number, NCT00806988.).

Nonrandomized Comparison of Coronary Artery Bypass Surgery and Percutaneous Coronary Intervention for the Treatment of Unprotected Left Main Coronary Artery Disease in Octogenarians

Background— The objective of the present study was to compare the midterm follow-up results of percutaneous coronary intervention (PCI) and coronary bypass graft surgery (CABG) for the treatment of unprotected left main coronary artery disease in octogenarians. Methods and Results— A total of 249 consecutive patients ≥80 years of age diagnosed with left main coronary artery disease underwent coronary revascularization in our center between January 2002 and January 2008; 145 patients underwent CABG, and 104 patients had PCI. Major adverse cardiac and cerebrovascular events (MACCE [cardiac death, myocardial infarction, cerebrovascular event, revascularization]) were evaluated at a mean follow-up of 23±16 months. Patients who underwent PCI were older; had higher creatinine levels, lower ejection fraction, and higher EuroSCORE; and presented more frequently with an acute coronary syndrome. Drug-eluting stents were used in 48% of PCI patients. A propensity score analysis was performed to adjust for baseline differences between the 2 groups. Survival free of cardiac death or myocardial infarction (PCI, 65.4%; CABG, 69.7%) and MACCE-free survival (PCI, 56.7%; CABG, 64.8%) at follow-up were similar between the groups (adjusted hazard ratio for survival free of cardiac death or myocardial infarction, 1.28; 95% CI, 0.64 to 2.56; P=0.47; adjusted hazard ratio for MACCE-free survival, 1.11; 95% CI, 0.59 to 2.0; P=0.73). The EuroSCORE value was an independent predictor of MACCE regardless of the type of revascularization (hazard ratio, 1.17 for each EuroSCORE increase of 1 point; 95% CI, 1.09 to 1.25; P<0.0001). Conclusions— In this single-center, nonrandomized study, there were no significant differences in cardiac death or myocardial infarction and MACCE between CABG and PCI for the treatment of left main coronary artery disease in octogenarians after a mean follow-up of 2 years. Baseline EuroSCORE was the most important predictor of MACCE regardless of the type of revascularization. Randomized studies comparing both revascularization strategies in this high-risk coronary population are warranted.

Impact of Prosthesis-Patient Mismatch on Long-Term Survival After Aortic Valve Replacement Influence of Age, Obesity, and Left Ventricular Dysfunction

OBJECTIVES This study was designed to evaluate the effect of valve prosthesis-patient mismatch (PPM) on late survival after aortic valve replacement (AVR) and to determine if this effect is modulated by patient age, body mass index (BMI), and pre-operative left ventricular (LV) function. BACKGROUND We recently reported that PPM is an independent predictor of operative mortality after AVR, particularly when associated with LV dysfunction. METHODS The indexed valve effective orifice area (EOA) was estimated in 2,576 patients having survived AVR and was used to define PPM as not clinically significant if it was >0.85 cm(2)/m(2), as moderate if >0.65 and < or =0.85 cm(2)/m(2), and severe if < or =0.65 cm(2)/m(2). RESULTS After adjustment for other risk factors, severe PPM was associated with increased late overall mortality (hazard ratio [HR]: 1.38; p = 0.03) and cardiovascular mortality (HR: 1.63; p = 0.0006) in the whole cohort. Severe PPM was also associated with increased overall mortality in patients <70 years old (HR: 1.77; p = 0.002) and in patients with a BMI <30 kg/m(2) (HR: 2.1; p = 0.006), but had no impact in older patients or in obese patients. Moderate PPM was a predictor of mortality in patients with LV ejection fraction <50% (HR: 1.21; p = 0.01), but not in patients with preserved LV function. CONCLUSIONS Moderate PPM is associated with increased late mortality in patients with LV dysfunction, but with normal prognosis in those with preserved LV function. Notwithstanding the previously demonstrated deleterious effect of severe PPM on early mortality, this factor appears to increase late mortality only in patients <70 years old and/or with a BMI <30 kg/m(2) or an LV ejection fraction <50%.

Surgical ablation of atrial fibrillation during mitral-valve surgery

BACKGROUND Among patients undergoing mitral-valve surgery, 30 to 50% present with atrial fibrillation, which is associated with reduced survival and increased risk of stroke. Surgical ablation of atrial fibrillation has been widely adopted, but evidence regarding its safety and effectiveness is limited. METHODS We randomly assigned 260 patients with persistent or long-standing persistent atrial fibrillation who required mitral-valve surgery to undergo either surgical ablation (ablation group) or no ablation (control group) during the mitral-valve operation. Patients in the ablation group underwent further randomization to pulmonary-vein isolation or a biatrial maze procedure. All patients underwent closure of the left atrial appendage. The primary end point was freedom from atrial fibrillation at both 6 months and 12 months (as assessed by means of 3-day Holter monitoring). RESULTS More patients in the ablation group than in the control group were free from atrial fibrillation at both 6 and 12 months (63.2% vs. 29.4%, P<0.001). There was no significant difference in the rate of freedom from atrial fibrillation between patients who underwent pulmonary-vein isolation and those who underwent the biatrial maze procedure (61.0% and 66.0%, respectively; P=0.60). One-year mortality was 6.8% in the ablation group and 8.7% in the control group (hazard ratio with ablation, 0.76; 95% confidence interval, 0.32 to 1.84; P=0.55). Ablation was associated with more implantations of a permanent pacemaker than was no ablation (21.5 vs. 8.1 per 100 patient-years, P=0.01). There were no significant between-group differences in major cardiac or cerebrovascular adverse events, overall serious adverse events, or hospital readmissions. CONCLUSIONS The addition of atrial fibrillation ablation to mitral-valve surgery significantly increased the rate of freedom from atrial fibrillation at 1 year among patients with persistent or long-standing persistent atrial fibrillation, but the risk of implantation of a permanent pacemaker was also increased. (Funded by the National Institutes of Health and the Canadian Institutes of Health Research; ClinicalTrials.gov number, NCT00903370.).

Obesity and Metabolic Syndrome Are Independent Risk Factors for Atrial Fibrillation After Coronary Artery Bypass Graft Surgery

Background— Postoperative atrial fibrillation (POAF) is a highly prevalent complication after cardiac surgery with substantial effects on outcomes. Previous studies have reported that obesity is a risk factor for POAF after cardiac surgery. However, it is unknown whether the metabolic syndrome (MS) also increases the risk of postoperative atrial fibrillation. Methods and Results— We retrospectively analyzed the association between obesity and MS and the incidence of new-onset POAF in a total of 5085 patients who underwent isolated coronary artery bypass grafting surgery with no concomitant valvular surgery. Of these patients, 1468 (29%) were obese (body mass index ≥30 kg/m2) and 2320 (46%) had a MS as defined by the NCEP-ATPIII. POAF occurred in 1374 (27%) of the patients. Obesity was associated (P<0.001) with increased incidence of POAF in the whole cohort as well as in patients >50 years old but not in patients ≤50 years old. In these patients, MS was the only metabolic factor to be significantly associated with higher incidence of POAF (12% versus 6%, P=0.01). In >50-year-old patients, mild (30 ≤ body mass index <35 kg/m2) and moderate–severe (body mass index ≥35 kg/m2) obesity were independently associated with a 1.4-fold (95% CI: 1.10 to 1.71; P=0.004) and 2.3-fold (95% CI: 1.71 to 3.13; P<0.0001) increase in the risk of POAF, respectively. In ≤50-year-old patients, MS (relative risk [RR]: 2.36; 95% CI: 1.10 to 5.12; P=0.02) but not obesity was independently associated with POAF. Conclusion— This study demonstrates that obesity is a powerful risk factor for the occurrence of POAF after isolated coronary artery bypass grafting surgery in patients older than 50 years. However, in the younger population, this association is not observed and MS is the only metabolic risk factor to be independently associated with POAF.

Aspirin Plus Clopidogrel Versus Aspirin Alone After Coronary Artery Bypass Grafting The Clopidogrel After Surgery for Coronary Artery Disease (CASCADE) Trial

Background— Clopidogrel inhibits intimal hyperplasia in animal studies and therefore may reduce saphenous vein graft (SVG) intimal hyperplasia after coronary artery bypass grafting. The Clopidogrel After Surgery for Coronary Artery DiseasE (CASCADE) study was undertaken to evaluate whether the addition of clopidogrel to aspirin inhibits SVG disease after coronary artery bypass grafting, as assessed at 1 year by intravascular ultrasound. Methods and Results— In this double-blind phase II trial, 113 patients undergoing coronary artery bypass grafting with SVGs were randomized to receive aspirin 162 mg plus clopidogrel 75 mg daily or aspirin 162 mg plus placebo daily for 1 year. The primary outcome was SVG intimal hyperplasia (mean intimal area) as determined by intravascular ultrasound at 1 year. Secondary outcomes were graft patency, major adverse cardiovascular events, and major bleeding. One-year intravascular ultrasound and coronary angiography were performed in 92 patients (81.4%). At 1 year, SVG intimal area did not differ significantly between the 2 groups (4.1±2.0 versus 4.5±2.1 mm2, aspirin-clopidogrel versus aspirin-placebo, P=0.44). Overall 1-year graft patency was 95.2% in the aspirin-clopidogrel group compared with 95.5% in the aspirin-placebo group (P=0.90), and SVG patency was 94.3% in the aspirin-clopidogrel group versus 93.2% in the aspirin-placebo group (P=0.69). Freedom from major adverse cardiovascular events at 1 year was 92.9±3.4% in the aspirin-clopidogrel group and 91.1±3.8% in the aspirin-placebo group (P=0.76). The incidence of major bleeding at 1 year was similar for the 2 groups (1.8% versus 0%, aspirin-clopidogrel versus aspirin-placebo, P=0.50). Conclusions— Compared with aspirin monotherapy, the combination of aspirin plus clopidogrel did not significantly reduce the process of SVG intimal hyperplasia 1 year after coronary artery bypass grafting. Clinical Trial Registration— URL: http://www.clinicaltrials.gov. Unique identifier: NCT00228423.Background— Clopidogrel inhibits intimal hyperplasia in animal studies and therefore may reduce saphenous vein graft (SVG) intimal hyperplasia after coronary artery bypass grafting. The Clopidogrel After Surgery for Coronary Artery DiseasE (CASCADE) study was undertaken to evaluate whether the addition of clopidogrel to aspirin inhibits SVG disease after coronary artery bypass grafting, as assessed at 1 year by intravascular ultrasound. Methods and Results— In this double-blind phase II trial, 113 patients undergoing coronary artery bypass grafting with SVGs were randomized to receive aspirin 162 mg plus clopidogrel 75 mg daily or aspirin 162 mg plus placebo daily for 1 year. The primary outcome was SVG intimal hyperplasia (mean intimal area) as determined by intravascular ultrasound at 1 year. Secondary outcomes were graft patency, major adverse cardiovascular events, and major bleeding. One-year intravascular ultrasound and coronary angiography were performed in 92 patients (81.4%). At 1 year, SVG intimal area did not differ significantly between the 2 groups (4.1±2.0 versus 4.5±2.1 mm2, aspirin-clopidogrel versus aspirin-placebo, P =0.44). Overall 1-year graft patency was 95.2% in the aspirin-clopidogrel group compared with 95.5% in the aspirin-placebo group ( P =0.90), and SVG patency was 94.3% in the aspirin-clopidogrel group versus 93.2% in the aspirin-placebo group ( P =0.69). Freedom from major adverse cardiovascular events at 1 year was 92.9±3.4% in the aspirin-clopidogrel group and 91.1±3.8% in the aspirin-placebo group ( P =0.76). The incidence of major bleeding at 1 year was similar for the 2 groups (1.8% versus 0%, aspirin-clopidogrel versus aspirin-placebo, P =0.50). Conclusions— Compared with aspirin monotherapy, the combination of aspirin plus clopidogrel did not significantly reduce the process of SVG intimal hyperplasia 1 year after coronary artery bypass grafting. Clinical Trial Registration— URL: . Unique identifier: [NCT00228423][1]. # Clinical Perspective {#article-title-35} [1]: /lookup/external-ref?link_type=CLINTRIALGOV&access_num=NCT00228423&atom=%2Fcirculationaha%2F122%2F25%2F2680.atom

Mitral Repair versus Replacement for Ischemic Mitral Regurgitation Comparison of Short-Term and Long-Term Survival

Background— When compared to mitral valve replacement (MVR), mitral valve repair (MVRp) is associated with better survival in patients with organic mitral regurgitation (MR). However, there is an important controversy about the type of surgical treatment that should be used in patients with ischemic MR. The objective of this study was to compare the postoperative outcome of MVRp versus MVR in patients with ischemic MR. Methods and Results— Preoperative and operative data of 370 patients with ischemic MR who underwent mitral valve surgery were prospectively collected and retrospectively analyzed. MVRp was performed in 50% of patients (n=186) and MVR in 50% (n=184). Although operative mortality was significantly lower after MVRp compared to MVR (9.7% versus 17.4%; P=0.03), overall 6-year survival was not statistically different between procedures (73±4% versus 67±4%; P=0.17). After adjusting for other risk factors and propensity score, the type of procedure (MVRp versus MVR) did not come out as an independent predictor of either operative (OR, 1.5; 95% CI, 0.7–2.9; P=0.34) or overall mortality (HR, 1.2; 95% CI, 0.7–1.9; P=0.52). Conclusion— As opposed to what has been reported in patients with organic MR, the results of this study suggest that MVRp is not superior to MVR with regard to operative and overall mortality in patients with ischemic MR. These findings provide support for the realization of a randomized trial comparing these 2 treatment modalities.

Impact of deep sternal wound infection management with vacuum-assisted closure therapy followed by sternal osteosynthesis: a 15-year review of 23 499 sternotomies

OBJECTIVE This study was undertaken to examine the outcome of patients with deep sternal wound infection (DSWI) now treated with vacuum-assisted closure (VAC) therapy as a bridge to sternal osteosynthesis with horizontal titanium plate fixation. METHODS From 1992 to 2007, a consecutive cohort of 23,499 patients underwent open-heart surgery (OHS) in our institution. The period under study was divided in two according to the use of therapeutic modalities: conventional (1992-2001, N=118 DSWI): debridement/drainage with primary closure and irrigation (N=37), debridement/drainage, open packing followed by pectoralis myocutaneous flaps (PMFs) (N=81); contemporary (2002-2007, N=149 DSWI): conventional treatment (N=24) and VAC therapy (N=125/83.8%). VAC was followed by sternal osteosynthesis with horizontal titanium plates in 92 patients (61.7%). RESULTS DSWI was diagnosed in 267 out of 23 499 (1.1%) patients of our entire series according to Center for Disease Control - Atlanta (CDC) criteria, 118 out of 13 180 (0.9%) in the first and 149 out of 10 319 (1.4%) in the second period (p=0.001). Hospital mortality (N=267/23,499) has been 10.25% for the entire cohort under study without any difference between groups (1992-2001: 11.4%; 2002-2007: 9.1%, p=0.67). More recently, VAC therapy (N=125) was associated with a lower mortality (4.8% vs 14.1%, p=0.01). Stepwise multivariable logistic regression analysis for both periods revealed that prolonged intubation in the intensive care unit (ICU), use of bilateral internal thoracic artery grafting (BIMA), diabetes, re-operation for bleeding and body mass index (BMI) >30 kgm(-2) are the most powerful predictors of DSWI. In the more recently treated patients using VAC therapy, combined procedures (valve and graft) also emerged as a significant predictor. For the entire study, Staphylococcus epidermidis (49.6%) has been the most frequently identified pathogen, followed by Staphylococcus aureus (38.8%). Methicillin-resistant S.aureus (MRSA) was observed in 4.9% of the cohort. Neither of these bacteria was associated with increased mortality. Survival analysis with Cox regression model and propensity score adjustment in patients with DSWI showed freedom from all-cause mortality at 1, 5 and 10 years to be, respectively, 91.8%, 80.4% and 61.3% compared with 94.0%, 85.5% and 70.2%, respectively, for patients submitted to OHS without DSWI (p=0.01). Early adjusted survival for patients with DSWI treated with VAC therapy was 92.8%, 89.8% and 88.0%, respectively, at 1, 2 and 3 years, compared with 83.0%, 76.4% and 61.3%, respectively, for patients with DSWI treated without VAC (p=0.02). CONCLUSIONS DSWI remains a major and challenging complication of OHS. VAC therapy with sternal preservation followed by delayed sternal osteosynthesis and PMF has been recently proposed as a new therapeutic strategy. Most patients treated with VAC therapy in our second group showed decreased perioperative mortality and increased short-term survival.