Concomitant Tricuspid Repair in Patients with Degenerative Mitral Regurgitation.

BACKGROUND: Tricuspid regurgitation is common in patients with severe degenerative mitral regurgitation. However, the evidence base is insufficient to inform a decision about whether to perform tricuspid-valve repair during mitral-valve surgery in patients who have moderate tricuspid regurgitation or less-than-moderate regurgitation with annular dilatation. METHODS: We randomly assigned 401 patients who were undergoing mitral-valve surgery for degenerative mitral regurgitation to receive a procedure with or without tricuspid annuloplasty (TA). The primary 2-year end point was a composite of reoperation for tricuspid regurgitation, progression of tricuspid regurgitation by two grades from baseline or the presence of severe tricuspid regurgitation, or death. RESULTS: Patients who underwent mitral-valve surgery plus TA had fewer primary-end-point events than those who underwent mitral-valve surgery alone (3.9% vs. 10.2%) (relative risk, 0.37; 95% confidence interval [CI], 0.16 to 0.86; P = 0.02). Two-year mortality was 3.2% in the surgery-plus-TA group and 4.5% in the surgery-alone group (relative risk, 0.69; 95% CI, 0.25 to 1.88). The 2-year prevalence of progression of tricuspid regurgitation was lower in the surgery-plus-TA group than in the surgery-alone group (0.6% vs. 6.1%; relative risk, 0.09; 95% CI, 0.01 to 0.69). The frequencies of major adverse cardiac and cerebrovascular events, functional status, and quality of life were similar in the two groups at 2 years, although the incidence of permanent pacemaker implantation was higher in the surgery-plus-TA group than in the surgery-alone group (14.1% vs. 2.5%; rate ratio, 5.75; 95% CI, 2.27 to 14.60). CONCLUSIONS: Among patients undergoing mitral-valve surgery, those who also received TA had a lower incidence of a primary-end-point event than those who underwent mitral-valve surgery alone at 2 years, a reduction that was driven by less frequent progression to severe tricuspid regurgitation. Tricuspid repair resulted in more frequent permanent pacemaker implantation. Whether reduced progression of tricuspid regurgitation results in long-term clinical benefit can be determined only with longer follow-up. (Funded by the National Heart, Lung, and Blood Institute and the German Center for Cardiovascular Research; ClinicalTrials.gov number, NCT02675244.).

Left Atrial Appendage Occlusion during Cardiac Surgery to Prevent Stroke.

BACKGROUND: Surgical occlusion of the left atrial appendage has been hypothesized to prevent ischemic stroke in patients with atrial fibrillation, but this has not been proved. The procedure can be performed during cardiac surgery undertaken for other reasons. METHODS: We conducted a multicenter, randomized trial involving participants with atrial fibrillation and a CHA2DS2-VASc score of at least 2 (on a scale from 0 to 9, with higher scores indicating greater risk of stroke) who were scheduled to undergo cardiac surgery for another indication. The participants were randomly assigned to undergo or not undergo occlusion of the left atrial appendage during surgery; all the participants were expected to receive usual care, including oral anticoagulation, during follow-up. The primary outcome was the occurrence of ischemic stroke (including transient ischemic attack with positive neuroimaging) or systemic embolism. The participants, research personnel, and primary care physicians (other than the surgeons) were unaware of the trial-group assignments. RESULTS: The primary analysis population included 2379 participants in the occlusion group and 2391 in the no-occlusion group, with a mean age of 71 years and a mean CHA2DS2-VASc score of 4.2. The participants were followed for a mean of 3.8 years. A total of 92.1% of the participants received the assigned procedure, and at 3 years, 76.8% of the participants continued to receive oral anticoagulation. Stroke or systemic embolism occurred in 114 participants (4.8%) in the occlusion group and in 168 (7.0%) in the no-occlusion group (hazard ratio, 0.67; 95% confidence interval, 0.53 to 0.85; P = 0.001). The incidence of perioperative bleeding, heart failure, or death did not differ significantly between the trial groups. CONCLUSIONS: Among participants with atrial fibrillation who had undergone cardiac surgery, most of whom continued to receive ongoing antithrombotic therapy, the risk of ischemic stroke or systemic embolism was lower with concomitant left atrial appendage occlusion performed during the surgery than without it. (Funded by the Canadian Institutes of Health Research and others; LAAOS III ClinicalTrials.gov number, NCT01561651.).

Enhancer promoter interactome and Mendelian randomization identify network of druggable vascular genes in coronary artery disease.

Coronary artery disease (CAD) is a multifactorial disorder, which is partly heritable. Herein, we implemented a mapping of CAD-associated candidate genes by using genome-wide enhancer-promoter conformation (H3K27ac-HiChIP) and expression quantitative trait loci (eQTL). Enhancer-promoter anchor loops from human coronary artery smooth muscle cells (HCASMC) explained 22% of the heritability for CAD. 3D enhancer-promoter genome mapping of CAD-genes in HCASMC was enriched in vascular eQTL genes. By using colocalization and Mendelian randomization analyses, we identified 58 causal candidate vascular genes including some druggable targets (MAP3K11, CAMK1D, PDGFD, IPO9 and CETP). A network analysis of causal candidate genes was enriched in TGF beta and MAPK pathways. The pharmacologic inhibition of causal candidate gene MAP3K11 in vascular SMC reduced the expression of athero-relevant genes and lowered cell migration, a cardinal process in CAD. Genes connected to enhancers are enriched in vascular eQTL and druggable genes causally associated with CAD.

Survival, ventricular arrhythmia, and implantable cardioverter-defibrillator usefulness in toxic cardiomyopathy due to substance abuse.

BACKGROUND: Toxic dilated cardiomyopathy (T-DCM) due to substance abuse is now recognized as a potential cause of severe left ventricular dysfunction. The burden of ventricular arrhythmias (VA) and the role of a prophylactic implantable cardioverter-defibrillator (ICD) are not well documented in this population. We aim to assess the usefulness of ICD implantation in a T-DCM cohort. METHODS: Patients younger than 65 years with a left ventricular ejection fraction (LVEF) < 35% followed at a tertiary center heart failure (HF) clinic between January 2003 and August 2019 were screened for inclusion. The diagnosis of T-DCM was confirmed after excluding other etiologies, and substance abuse was established according to the DSM-5 criteria. The composite primary endpoints were arrhythmic syncope, sudden cardiac death (SCD), or death of unknown cause. The secondary endpoints were the occurrence of sustained VA and/or appropriate therapies in ICD carriers. RESULTS: Thirty-eight patients were identified, and an ICD was implanted in 19 (50%) of these patients, only one for secondary prevention. The primary outcome was similar between the two groups (ICD vs. non-ICD; p = 1.00). After a mean follow-up of 33 ± 36 months, only two VA episodes were reported in the ICD group. Three patients received inappropriate ICD therapies. One ICD implantation was complicated with cardiac tamponade. Twenty-three patients (61%) had an LVEF ≥35% at 12 months. CONCLUSION: VA are infrequent in the T-DCM population. The prophylactic ICD benefit was not observed in our cohort. The ideal timing for potential prophylactic ICD implantation in this population needs further studies.

Posterior left pericardiotomy for the prevention of atrial fibrillation after cardiac surgery: an adaptive, single-centre, single-blind, randomised, controlled trial.

BACKGROUND: Atrial fibrillation is the most common complication after cardiac surgery and is associated with extended in-hospital stay and increased adverse outcomes, including death and stroke. Pericardial effusion is common after cardiac surgery and can trigger atrial fibrillation. We tested the hypothesis that posterior left pericardiotomy, a surgical manoeuvre that drains the pericardial space into the left pleural cavity, might reduce the incidence of atrial fibrillation after cardiac surgery. METHODS: In this adaptive, randomised, controlled trial, we recruited adult patients (aged ≥18 years) undergoing elective interventions on the coronary arteries, aortic valve, or ascending aorta, or a combination of these, performed by members of the Department of Cardiothoracic Surgery from Weill Cornell Medicine at the New York Presbyterian Hospital in New York, NY, USA. Patients were eligible if they had no history of atrial fibrillation or other arrhythmias or contraindications to the experimental intervention. Eligible patients were randomly assigned (1:1), stratified by CHA2DS2-VASc score and using a mixed-block randomisation approach (block sizes of 4, 6, and 8), to posterior left pericardiotomy or no intervention. Patients and assessors were blinded to treatment assignment. Patients were followed up until 30 days after hospital discharge. The primary outcome was the incidence of atrial fibrillation during postoperative in-hospital stay, which was assessed in the intention-to-treat (ITT) population. Safety was assessed in the as-treated population. This study is registered with ClinicalTrials.gov, NCT02875405, and is now complete. FINDINGS: Between Sept 18, 2017, and Aug 2, 2021, 3601 patients were screened and 420 were included and randomly assigned to the posterior left pericardiotomy group (n=212) or the no intervention group (n=208; ITT population). The median age was 61·0 years (IQR 53·0-70·0), 102 (24%) patients were female, and 318 (76%) were male, with a median CHA2DS2-VASc score of 2·0 (IQR 1·0-3·0). The two groups were balanced with respect to clinical and surgical characteristics. No patients were lost to follow-up and data completeness was 100%. Three patients in the posterior left pericardiotomy group did not receive the intervention. In the ITT population, the incidence of postoperative atrial fibrillation was significantly lower in the posterior left pericardiotomy group than in the no intervention group (37 [17%] of 212 vs 66 [32%] of 208 [p=0·0007]; odds ratio adjusted for the stratification variable 0·44 [95% CI 0·27-0·70; p=0·0005]). Two (1%) of 209 patients in the posterior left pericardiotomy group and one (<1%) of 211 in the no intervention group died within 30 days after hospital discharge. The incidence of postoperative pericardial effusion was lower in the posterior left pericardiotomy group than in the no intervention group (26 [12%] of 209 vs 45 [21%] of 211; relative risk 0·58 [95% CI 0·37-0·91]). Postoperative major adverse events occurred in six (3%) patients in the posterior left pericardiotomy group and in four (2%) in the no intervention group. No posterior left pericardiotomy related complications were seen. INTERPRETATION: Posterior left pericardiotomy is highly effective in reducing the incidence of atrial fibrillation after surgery on the coronary arteries, aortic valve, or ascending aorta, or a combination of these without additional risk of postoperative complications. FUNDING: None.

Rationale and design of a randomized trial evaluating an external support device for saphenous vein coronary grafts.

BACKGROUND: Coronary artery bypass grafting (CABG) is the most common revascularization approach for the treatment of multi-vessel coronary artery disease. While the internal mammary artery is nearly universally used to bypass the left anterior descending coronary artery, autologous saphenous vein grafts (SVGs) are still the most frequently used conduits to grafts the remaining coronary artery targets. Long-term failure of these grafts, however, continues to limit the benefits of surgery. METHODS: The Cardiothoracic Surgical Trials Network trial of the safety and effectiveness of a Venous External Support (VEST) device is a randomized, multicenter, within-patient trial comparing VEST-supported versus unsupported saphenous vein grafts in patients undergoing CABG. Key inclusion criteria are the need for CABG with a planned internal mammary artery to the left anterior descending and two or more saphenous vein grafts to other coronary arteries. The primary efficacy endpoint of the trial is SVG intimal hyperplasia (plaque + media) area assessed by intravascular ultrasound at 12 months post randomization. Occluded grafts are accounted for in the analysis of the primary endpoint. Secondary confirmatory endpoints are lumen diameter uniformity and graft failure (>50% stenosis) assessed by coronary angiography at 12 months. The safety endpoints are the occurrence of major adverse cardiac and cerebrovascular events and hospitalization within 5 years from randomization. CONCLUSIONS: The results of the VEST trial will determine whether the VEST device can safely limit SVG intimal hyperplasia in patients undergoing CABG as treatment for coronary atherosclerotic disease.

Effect of concomitant surgical atrial fibrillation ablation in patients with reduced left ventricle ejection fraction: A propensity-score matching analysis.

BACKGROUND: Atrial fibrillation (AF) is common in patients with reduced left ventricle ejection fraction (RLVEF). The impact of concomitant surgical atrial fibrillation ablation (SAFA) in patients with RLVEF is uncertain. The purpose of this study was to assess the outcomes of concomitant SAFA in patients with RLVEF undergoing heart surgery on heart failure (HF) rehospitalization and mortality. METHODS: Using a local registry and electronic health records linked with provincial civil register survival data from July 2002 to April 2019, we analyzed treatment and outcomes in a cohort of patients with AF and HF defined by left ventricle ejection fraction (LVEF) ≤40%. Health records were used to collect treatment and International Classification of Diseases (ICD 10) codes to determine outcomes. A negative binomial model was used to compare outcomes such as all-cause mortality and rehospitalization for heart failure. RESULTS: The cohort included 682 patients with RLVEF and AF who underwent coronary artery bypass graft and/or valve surgery. A total of 196 patients (29%) underwent concomitant SAFA. After matching, 132 patients with concomitant SAFA were compared to 159 patients who did not undergo concomitant SAFA. At 6.0 ± 3.7 years of follow-up, concomitant SAFA was not associated with lower all-cause mortality (p = .9861) and reduction in rehospitalizations for heart failure decompensation (p = .31) compared to patients who did not have concomitant SAFA performed. Postoperatively, concomitant SAFA might be associated with less vasopressor and mechanical support use (p = .01). CONCLUSIONS: Concomitant SAFA during index cardiac surgery is safe but does not reduce mortality or rehospitalizations for HF. The effects of concomitant SAFA in the context of RLVEF need to be better studied with prospective trials.

Generalizability of Reduction of Cardiovascular Events with Icosapent Ethyl-Intervention Trial in patients with a history of coronary artery bypass graft surgery.

PURPOSE OF REVIEW: Following coronary artery bypass grafting (CABG), there remains persistent risk of ischemic events despite secondary prevention strategies, including low-density lipoprotein cholesterol lowering. Although REDUCE-IT recently demonstrated the benefits of icosapent ethyl (IPE) on reducing ischemic events in a broad population of primary and secondary prevention patients, its generalizability to a contemporary CABG population is not known. This article aims to ascertain the proportion of patients with a history of CABG that would be eligible for IPE treatment. RECENT FINDINGS: A review of recent literature highlights the presence of residual ischemic following CABG. Using the Québec Heart Database, a repository of contemporary Canadian cardiac patient information, was searched between 1 January 2006 and 31 December 2016, to ascertain generalizability of IPE. SUMMARY: In a large (N = 12 641), contemporary, Canadian cohort of patients with a history of CABG and currently on statin therapy, 21.9, 33.6 and 26.4% would be eligible for IPE, according to REDUCE-IT, Health Canada, and Food and Drug Administration criteria, respectively. These analyses would support IPE as an adjunct to secondary prevention therapies post-CABG.

Prognosis of functional mitral regurgitation after aortic valve replacement for pure severe aortic stenosis.

OBJECTIVE: Whether patients with severe aortic stenosis (AS) and significant functional mitral regurgitation (MR) should undergo isolated aortic (aortic valve replacement [AVR]) or double aortic-mitral valve procedure (DVP) remains controversial. We sought to determine outcomes of such patients undergoing surgical (surgical aortic valve replacement [SAVR]) and transcatheter AVR (TAVR) or DVP, identify echocardiographic parameters predictive of significant residual MR after isolated AVR, and determine its impact on long-term survival. METHODS: Data prospectively collected from 736 consecutive patients with severe AS and significant MR undergoing AVR or DVP were retrospectively analyzed. Exclusion of organic MR, other valve diseases and concomitant CABG yielded a final population of 74 patients with significant functional MR (32 TAVR, 23 SAVR, 19 DVP). Demographics, postoperative complications and age-adjusted survival were compared. Echocardiographic predictors of significant residual MR and its impact on survival were analyzed for patients undergoing isolated AVR. RESULTS: In the isolated AVR group, MR improvement occurred in 60% of patients and was associated with a significant increase in survival compared to persistence of significant MR (p = .03). Patients with improved MR had significantly greater preoperative left ventricular dilatation (LVEDD: 49 vs. 43 mm, p = .001; LVESD: 35 vs. 29 mm, p = .03; LVEDV: 101 vs. 71 ml, p = .0003; LVESV: 57 vs. 33 ml, p = .002). There was no significant difference in perioperative mortality (5.3 vs. 4.4 vs. 9.4%, p = .85) or age-adjusted long-term survival between isolated AVR and DVP groups (76.3 vs. 84.2% survival at 2-year follow-up, p = .26), or between SAVR, TAVR and DVP groups (78.2 vs. 75.0 vs. 84.2% survival at 2-year follow-up, p = .13). CONCLUSIONS: After isolated AVR, MR improvement occurs in 60% of patients. It is predicted by greater ventricular dimensions and associated with significantly better long-term survival. Whether a staged approach with transcatheter correction of MR should be considered in patients with significant residual MR following AVR remains undetermined.

Use of extracorporeal membrane oxygenation for heart graft dysfunction in adults: incidence, risk factors and outcomes in a multicentric study.

BACKGROUND: The decision about whether to use venoarterial extracorporeal membrane oxygenation (VA-ECMO) in patients with cardiac graft dysfunction (GD) is usually made on a case-by-case basis and is guided by the team's experience. We aimed to determine the incidence of VA-ECMO use after heart transplantation (HT), to assess early- and long-term outcomes and to assess risk factors for the need for VA-ECMO and early mortality in these patients. METHODS: We included adults who underwent heart transplantation at 3 cardiac centres who met the most recent International Society for Heart and Lung Transplantation definition of graft dysfunction (GD) over a 10-year period. Pre-transplant, intraoperative and posttransplant characteristics of the heart recipients as well as donor characteristics were analyzed and compared among recipients with GD treated with and without VA-ECMO. RESULTS: There were 135 patients with GD in this study, of whom 66 were treated with VA-ECMO and 69 were not. The mean follow-up averaged 81.2 months (standard deviation 36 mo, range 0-184 mo); follow-up was complete in 100% of patients. The overall incidence of GD (30%) and of VA-ECMO use increased over the study period. We did not identify any predictive pre-transplantation factors for VA-ECMO use, but patients who required VA-ECMO had higher serum lactate levels and higher inotropes doses after HT. The overall survival rates were 83% and 42% at 1 year and 78% and 40% at 5 years among patients who received only medical treatment and those who received VA-ECMO, respectively. Delayed initiation of VA-ECMO and postoperative bleeding were strongly associated with increased in-hospital mortality. CONCLUSION: The incidence of GD increased over the study period, and the need for VA-ECMO among patients with GD remains difficult to predict. In-hospital mortality decreased over time but remained high among patients who required VA-ECMO, especially among patients with delayed initiation of VA-ECMO.

Annulus root enlargement during redo aortic valve replacement: Perioperative results and hemodynamic impact.

OBJECTIVES: Redo aortic valve replacement (AVR) might present an increased risk for predicted patient-prosthesis mismatch (PPM). Aortic root enlargement (ARE) procedures can decrease PPM and improve hemodynamic parameters. It is crucial to evaluate the safety of ARE in the context of redo AVR to allow better patient selection. METHODS: This is a matched case-control study of 125 patients who underwent a redo AVR between 1991 and 2016, 21 patients had a concomitant ARE procedure. Patients were matched for age, gender, presence of coronary artery disease, renal clearance, left ventricular ejection fraction, and body mass index. The primary outcome was the occurrence of major adverse cardiovascular events (MACE). Secondary outcomes were postoperative impact of the ARE procedures on echocardiographic measurements and survival. RESULTS: Preoperatively, indexed aortic valve area (0.49 vs 0.66 cm2 /m2 ; P = .02) and left ventricle outflow tract diameters (20.1 vs 22.2 mm; P < .01) were significantly smaller in the ARE group. ARE procedures increased the aortic valve area by an average of 0.4 cm2 (pre = 0.9, post = 1.3; P < .01), with a reduction of maximum and mean transvalvular gradients of 26.6 mm Hg (pre = 56.8, post = 30.2; P < .01) and 17.1 mm Hg (pre = 31.9, post = 14.8; P < .01), respectively. Postoperatively, the occurrence of MACE was similar (ARE = 19%, no ARE = 14%; P = .68). Survival rates were similar (P = .29). CONCLUSIONS: For patients undergoing redo AVR, ARE is not associated with higher perioperative mortality and morbidity when compared with patients undergoing AVR without ARE. The fear of perioperative complications potentially associated with ARE should not be a prohibiting factor in symptomatic redo patients with small aortic annulus and predicted PPM.

Rate, Timing, Correlates, and Outcomes of Hemodynamic Valve Deterioration After Bioprosthetic Surgical Aortic Valve Replacement.

BACKGROUND: The incidence of structural valve deterioration after bioprosthesis (BP) aortic valve replacement (AVR) established on the basis of reoperation may substantially underestimate the true incidence. The objective is to determine the rate, timing, correlates, and association between hemodynamic valve deterioration (HVD) and outcomes assessed by Doppler echocardiography after surgical BP AVR. METHODS: A total of 1387 patients (62.2% male, 70.5±7.8 years of age) who underwent BP AVR were included in this retrospective study. Baseline echocardiography was performed at a median time of 4.1 (1.3-6.5) months after AVR. All patients had an echocardiographic follow-up ≥2 years after AVR (926 at least 5 years and 385 at least 10 years). HVD was defined by Doppler assessment as a ≥10 mm Hg increase in mean gradient or worsening of transprosthetic regurgitation ≥1/3 class. HVD was classified according to the timing after AVR: "very early," during the first 2-years; "early," between 2 and 5 years; "midterm," between 5 and 10 years; and "long-term," >10 years. RESULTS: A total of 428 patients (30.9%) developed HVD. Among these patients, 52 (12.0%) were classified as "very early," 129 (30.1%) as "early," 158 (36.9%) as "midterm," and 89 (20.8%) as "long-term" HVD. Factors independently associated with HVD occurring within the first 5 years after AVR were diabetes mellitus ( P=0.01), active smoking ( P=0.01), renal insufficiency ( P=0.01), baseline postoperative mean gradient ≥15 mm Hg ( P=0.04) or transprosthetic regurgitation ≥mild ( P=0.04), and type of BP (stented versus stentless, P=0.003). Factors associated with HVD occurring after the fifth year after AVR were female sex ( P=0.03), warfarin use ( P=0.007), and BP type ( P<0.001). HVD was independently associated with mortality (hazard ratio, 2.18; 95% CI, 1.86-2.57; P<0.001). CONCLUSIONS: HVD as identified by Doppler echocardiography occurred in one third of patients and was associated with a 2.2-fold higher adjusted mortality. Diabetes mellitus and renal insufficiency were associated with early HVD, whereas female sex, warfarin use, and stented BPs (versus stentless) were associated with late HVD.

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

BACKGROUND: In a randomized trial comparing mitral-valve repair with mitral-valve replacement in patients with severe ischemic mitral regurgitation, we found no significant difference in the left ventricular end-systolic volume index (LVESVI), survival, or adverse events at 1 year after surgery. However, patients in the repair group had significantly more recurrences of moderate or severe mitral regurgitation. We now report the 2-year outcomes of this trial. METHODS: We randomly assigned 251 patients to mitral-valve repair or replacement. Patients were followed for 2 years, and clinical and echocardiographic outcomes were assessed. RESULTS: Among surviving patients, the mean (±SD) 2-year LVESVI was 52.6±27.7 ml per square meter of body-surface area with mitral-valve repair and 60.6±39.0 ml per square meter with mitral-valve replacement (mean changes from baseline, -9.0 ml per square meter and -6.5 ml per square meter, respectively). Two-year mortality was 19.0% in the repair group and 23.2% in the replacement group (hazard ratio in the repair group, 0.79; 95% confidence interval, 0.46 to 1.35; P=0.39). The rank-based assessment of LVESVI at 2 years (incorporating deaths) showed no significant between-group difference (z score=-1.32, P=0.19). The rate of recurrence of moderate or severe mitral regurgitation over 2 years was higher in the repair group than in the replacement group (58.8% vs. 3.8%, P<0.001). There were no significant between-group differences in rates of serious adverse events and overall readmissions, but patients in the repair group had more serious adverse events related to heart failure (P=0.05) and cardiovascular readmissions (P=0.01). On the Minnesota Living with Heart Failure questionnaire, there was a trend toward greater improvement in the replacement group (P=0.07). CONCLUSIONS: In patients undergoing mitral-valve repair or replacement for severe ischemic mitral regurgitation, we observed no significant between-group difference in left ventricular reverse remodeling or survival at 2 years. Mitral regurgitation recurred more frequently in the repair group, resulting in more heart-failure-related adverse events and cardiovascular admissions. (Funded by the National Institutes of Health and Canadian Institutes of Health Research; ClinicalTrials.gov number, NCT00807040.).

Rate Control versus Rhythm Control for Atrial Fibrillation after Cardiac Surgery.

BACKGROUND: Atrial fibrillation after cardiac surgery is associated with increased rates of death, complications, and hospitalizations. In patients with postoperative atrial fibrillation who are in stable condition, the best initial treatment strategy--heart-rate control or rhythm control--remains controversial. METHODS: Patients with new-onset postoperative atrial fibrillation were randomly assigned to undergo either rate control or rhythm control. The primary end point was the total number of days of hospitalization within 60 days after randomization, as assessed by the Wilcoxon rank-sum test. RESULTS: Postoperative atrial fibrillation occurred in 695 of the 2109 patients (33.0%) who were enrolled preoperatively; of these patients, 523 underwent randomization. The total numbers of hospital days in the rate-control group and the rhythm-control group were similar (median, 5.1 days and 5.0 days, respectively; P=0.76). There were no significant between-group differences in the rates of death (P=0.64) or overall serious adverse events (24.8 per 100 patient-months in the rate-control group and 26.4 per 100 patient-months in the rhythm-control group, P=0.61), including thromboembolic and bleeding events. About 25% of the patients in each group deviated from the assigned therapy, mainly because of drug ineffectiveness (in the rate-control group) or amiodarone side effects or adverse drug reactions (in the rhythm-control group). At 60 days, 93.8% of the patients in the rate-control group and 97.9% of those in the rhythm-control group had had a stable heart rhythm without atrial fibrillation for the previous 30 days (P=0.02), and 84.2% and 86.9%, respectively, had been free from atrial fibrillation from discharge to 60 days (P=0.41). CONCLUSIONS: Strategies for rate control and rhythm control to treat postoperative atrial fibrillation were associated with equal numbers of days of hospitalization, similar complication rates, and similarly low rates of persistent atrial fibrillation 60 days after onset. Neither treatment strategy showed a net clinical advantage over the other. (Funded by the National Institutes of Health and the Canadian Institutes of Health Research; ClinicalTrials.gov number, NCT02132767.).

Two-Year Outcomes of Surgical Treatment of Moderate 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.).

Clinical and echocardiographic presentation of postmyocardial infarction papillary muscle rupture.

BACKGROUND: Severe mitral regurgitation (MR) can occur following myocardial infarction (MI) with either partial or complete papillary muscle rupture (pPMR or cPMR). Although the incidence of this complication has significantly decreased, it is still associated with significant mortality. We sought to evaluate the different echocardiographic and clinical presentations of pPMR and cPMR. METHODS AND RESULTS: A review of all the urgent procedures for ischemic MR between January 2000 and June 2016 was performed to identify patients who underwent surgery for PMR. Surgical protocols and echocardiographic studies were used to identify patients with cPMR and pPMR. A total of 37 patients had cardiac surgery for PMR (18 cPMR, 19 pPMR). All patients with cPMR were in cardiogenic shock at the time of diagnosis, as opposed to only 53% of patients with pPMR (P = 0.0008). Between the time of diagnosis and surgery, 7 patients with pPMR developed cardiogenic shock. Transthoracic echocardiography (TTE) led to the diagnosis in 72% of cPMR and 32% of pPMR (P = 0.02). TEE had a yield of 100% for both cPMR and pPMR. Six pathologic varieties of post-MI PMR were recognized on echocardiography and during surgery. Early postoperative, 1 (72% vs 84%), 3 (67% vs 84%), and 5 years (67% vs 74%) survival rates were similar for cPMR and pPMR (P = 0.26). CONCLUSIONS: Partial PMR is associated with a different clinical and echocardiographic presentation than cPMR. Still, most pPMR patients progress toward cardiogenic shock. Prompt diagnosis and referral for surgery are critical and could potentially decrease mortality.

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.).

Impact of Left Ventricular to Mitral Valve Ring Mismatch on Recurrent Ischemic Mitral Regurgitation After Ring Annuloplasty.

BACKGROUND: In ischemic mitral regurgitation (IMR), ring annuloplasty is associated with a significant rate of recurrent MR. Ring size is based on intertrigonal distance without consideration of left ventricular (LV) size. However, LV size is an important determinant of mitral valve (MV) leaflet tethering before and after repair. We aimed to determine whether LV-MV ring mismatch (mismatch of LV size relative to ring size) is associated with recurrent MR in patients with IMR after restrictive ring annuloplasty. METHODS: Patients with moderate or severe IMR from the 2 Cardiothoracic Surgical Trials Network IMR trials who received MV repair were examined at 1 year after surgery. Baseline LV size was assessed by LV end-diastolic dimension and LV end-systolic dimension (LVESd). LV-MV ring mismatch was calculated as the ratio of LV to ring size (LV end-diastolic dimension/ring size and LVESd/ring size). RESULTS: At 1 year after ring annuloplasty, 45 of 214 patients with MV repair (21%) had moderate or greater MR. In univariable logistic regression analysis, larger LVESd (P=0.02) and LVESd/ring size (P=0.007) were associated with recurrent MR. In multivariable models adjusted for age, sex, baseline LV ejection fraction, and severe IMR, only LVESd/ring size (odd ratio per 0.5 increase, 2.20; 95% confidence interval, 1.05-4.62; P=0.038) remained significantly associated with 1-year MR recurrence. CONCLUSIONS: LV-MV ring size mismatch is associated with increased risk of MR recurrence. This finding may be helpful in guiding choice of ring size to prevent recurrent MR in patients undergoing MV repair and in identifying patients who may benefit from MV repair with additional subvalvular intervention or MV replacement rather than repair alone. CLINICAL TRIAL REGISTRATION: URL:http://clinicaltrials.gov. Unique identifiers: NCT00806988 and NCT00807040.