Effect of cardiosphere-derived cells on segmental myocardial function after myocardial infarction: ALLSTAR randomised clinical trial.

BACKGROUND: Most cell therapy trials failed to show an improvement in global left ventricular (LV) function measures after myocardial infarction (MI). Myocardial segments are heterogeneously impacted by MI. Global LV function indices are not able to detect the small treatment effects on segmental myocardial function which may have prognostic implications for cardiac events. We aimed to test the efficacy of allogeneic cardiosphere-derived cells (CDCs) for improving regional myocardial function and contractility. METHODS: In this exploratory analysis of a randomised clinical trial, 142 patients with post-MI with LVEF <45% and 15% or greater LV scar size were randomised in 2:1 ratio to receive intracoronary infusion of allogenic CDCs or placebo, respectively. Change in segmental myocardial circumferential strain (Ecc) by MRI from baseline to 6 months was compared between CDCs and placebo groups. RESULTS: In total, 124 patients completed the 6-month follow-up (mean (SD) age 54.3 (10.8) and 108 (87.1%) men). Segmental Ecc improvement was significantly greater in patients receiving CDC (-0.5% (4.0)) compared with placebo (0.2% (3.7), p=0.05). The greatest benefit for improvement in segmental Ecc was observed in segments containing scar tissue (change in segmental Ecc of -0.7% (3.5) in patients receiving CDC vs 0.04% (3.7) in the placebo group, p=0.04). CONCLUSIONS: In patients with post-MI LV dysfunction, CDC administration resulted in improved segmental myocardial function. Our findings highlight the importance of segmental myocardial function indices as an endpoint in future clinical trials of patients with post-MI. TRIAL REGISTRATION NUMBER: NCT01458405.

Intracoronary ALLogeneic heart STem cells to Achieve myocardial Regeneration (ALLSTAR): a randomized, placebo-controlled, double-blinded trial.

AIMS: Cardiosphere-derived cells (CDCs) are cardiac progenitor cells that exhibit disease-modifying bioactivity in various models of cardiomyopathy and in previous clinical studies of acute myocardial infarction (MI), dilated cardiomyopathy, and Duchenne muscular dystrophy. The aim of the study was to assess the safety and efficacy of intracoronary administration of allogeneic CDCs in the multicentre, randomized, double-blinded, placebo-controlled, intracoronary ALLogeneic heart STem cells to Achieve myocardial Regeneration (ALLSTAR) trial. METHODS AND RESULTS: We enrolled patients 4 weeks to 12 months after MI, with left ventricular ejection fraction (LVEF) ≤45% and LV scar size ≥15% of LV mass by magnetic resonance imaging (MRI). A pre-specified interim analysis was performed when 6-month MRI data were available. The trial was subsequently stopped due to the low probability of detecting a significant treatment effect of CDCs based on the primary endpoint. Patients were randomly allocated in a 2:1 ratio to receive CDCs or placebo in the infarct-related artery by stop-flow technique. The primary safety endpoint was the occurrence, during 1-month post-intracoronary infusion, of acute myocarditis attributable to allogeneic CDCs, ventricular tachycardia- or ventricular fibrillation-related death, sudden unexpected death, or a major adverse cardiac event (death or hospitalization for heart failure or non-fatal MI or need for left ventricular assist device or heart transplant). The primary efficacy endpoint was the relative percentage change in infarct size at 12 months post-infusion as assessed by contrast-enhanced cardiac MRI. We randomly allocated 142 eligible patients of whom 134 were treated (90 to the CDC group and 44 to the placebo group). The mean baseline LVEF was 40% and the mean scar size was 22% of LV mass. No primary safety endpoint events occurred. There was no difference in the percentage change from baseline in scar size (P = 0.51) between CDCs and placebo groups at 6 months. Compared with placebo, there were significant reductions in LV end-diastolic volume (P = 0.02), LV end-systolic volume (P = 0.02), and N-terminal pro b-type natriuretic peptide (NT-proBNP) (P = 0.02) at 6 months in CDC-treated patients. CONCLUSION: Intracoronary infusion of allogeneic CDCs in patients with post-MI LV dysfunction was safe but did not reduce scar size relative to placebo at 6 months. Nevertheless, the reductions in LV volumes and NT-proBNP reveal disease-modifying bioactivity of CDCs. TRIAL REGISTRATION: Clinicaltrials.gov identifier: NCT01458405.

Allogeneic cardiosphere-derived cells for the treatment of heart failure with reduced ejection fraction: the Dilated cardiomYopathy iNtervention with Allogeneic MyocardIally-regenerative Cells (DYNAMIC) trial.

AIMS: The DYNAMIC trial assessed the safety and explored the efficacy of multivessel intracoronary infusion of allogeneic cardiosphere-derived cells (CDCs) in patients with heart failure and reduced ejection fraction (HFrEF). Here we report the results of the DYNAMIC trial. METHODS AND RESULTS: We enrolled 14 patients with EF ≤35% and NYHA Class III-IV despite maximal medical and device-based therapy in this single-centre, open-label trial. Intracoronary catheterisation delivered four escalating doses (totalling 37.5-75 million cells) by sequential non-occlusive technique to all three major coronary arteries. The primary safety endpoint was a composite of post-infusion TIMI flow, ventricular tachycardia/fibrillation, sudden death, major adverse cardiac events or acute myocarditis within 72 hours. Twelve patients were male and EF averaged 23.0% (±4.5%). No primary safety endpoints were observed. Two patients died of HFrEF progression nine and 12 months following infusion. Compared to baseline, there was an improvement in EF (26.8% vs 22.9%, p=0.023) and left ventricular end-systolic volume (139.5 vs 177.8 cm3, p=0.03) at six months. Quality of life (QoL) scores and NYHA class (p=0.006) improved at six months. At 12 months, the improvement in EF and QoL remained significant. CONCLUSIONS: Global intracoronary infusion of allogeneic CDCs is safe and feasible. The efficacy of allogeneic CDCs in HFrEF needs to be tested in larger randomised trials.

Cardiac and skeletal muscle effects in the randomized HOPE-Duchenne trial.

OBJECTIVE: To assess the feasibility, safety, and efficacy of intracoronary allogeneic cardiosphere-derived cells (CAP-1002) in patients with Duchenne muscular dystrophy (DMD). METHODS: The Halt Cardiomyopathy Progression (HOPE)-Duchenne trial is a phase I/II, randomized, controlled, open-label trial (NCT02485938). Patients with DMD >12 years old, with substantial myocardial fibrosis, were randomized (1:1) to usual care (control) or global intracoronary infusion of CAP-1002 (75 million cells). Participants were enrolled at 3 US medical centers between January and August 2016 and followed for 12 months. An independent Data and Safety Monitoring Board provided safety oversight. Cardiac function and structure were assessed by MRI, and analyzed by a blinded core laboratory. Skeletal muscle function was assessed by performance of the upper limb (PUL). RESULTS: Twenty-five eligible patients (mean age 17.8 years; 68% wheelchair-dependent) were randomized to CAP-1002 (n = 13) or control (n = 12). Incidence of treatment-emergent adverse events was similar between groups. Compared to baseline, MRI at 12 months revealed significant scar size reduction and improvement in inferior wall systolic thickening in CAP-1002 but not control patients. Mid-distal PUL improved at 12 months in 8 of 9 lower functioning CAP-1002 patients, and no controls (p = 0.007). CONCLUSIONS: Intracoronary CAP-1002 in DMD appears safe and demonstrates signals of efficacy on both cardiac and upper limb function for up to 12 months. Thus, future clinical research on CAP-1002 treatment of DMD cardiac and skeletal myopathies is warranted. CLASSIFICATION OF EVIDENCE: This phase I/II study provides Class II evidence that for patients with DMD, intracoronary CAP-1002 is feasible and appears safe and potentially effective.

Combining Stem Cell Therapy for Advanced Heart Failure and Ventricular Assist Devices: A Review.

The use of stem cell therapy in combination with a left ventricular assist device (LVAD) for patients with advanced heart failure (HF) is an attractive concept with the potential to alter the natural history of HF. Cell therapy trials for HF have demonstrated excellent safety and encouraging results, but current rates of myocardial recovery after LVAD implantation are limited. Early trials combining these 2 therapies to increase the likelihood of recovery and to potentially obviate the need for subsequent transplantation appear promising. Additionally, the application of cell therapy to patients undergoing LVAD implantation as a bridge to cardiac transplantation creates an opportunity to examine cardiac tissue before and after treatment and to study the mechanism of benefit. Despite the promise, there is a paucity of data for the combination of stem cell therapy with LVAD insertion in patients with HF. Of 11 case series or clinical trials, the largest enrolled 30 patients. We highlight clinical trials using stem cell therapy for end-stage HF most relevant to an LVAD patient population and comprehensively review the preclinical and clinical studies of combined stem cell therapy and long-term mechanical circulatory support. Based on the available clinical trials, the combination of stem cell therapy and LVAD support is a promising approach but requires further clinical refinement, with additional clinical data and larger numbers of patients required to support its clinical application.

ALLogeneic Heart STem Cells to Achieve Myocardial Regeneration (ALLSTAR) Trial: Rationale and Design.

Autologous cardiosphere-derived cells (CDCs) were the first therapeutic modality to demonstrate myocardial regeneration with a decrease in scar size and an increase in viable, functional tissue. Widespread applicability of autologous CDC therapy is limited by the need for patient-specific myocardial biopsy, cell processing, and quality control, resulting in delays to therapy and inherent logistical and economic constraints. Preclinical data had demonstrated equivalent efficiency of allogeneic to autologous CDCs. The ALLogeneic Heart STem Cells to Achieve Myocardial Regeneration (ALLSTAR) trial is a multicenter randomized, double-blind, placebo-controlled phase 1/2 safety and efficacy trial of intracoronary delivery of allogeneic CDCs (CAP-1002) in patients with myocardial infarction (MI) and ischemic left ventricular dysfunction. The phase 1 safety cohort enrolled 14 patients in an open-label, nonrandomized, dose-escalation safety trial. The phase 2 trial is a double-blind, randomized, placebo-controlled trial that will compare intracoronary CDCs to placebo in a 2:1 allocation and will enroll up to 120 patients. The primary endpoint for both phases is safety at 1 month. For phase 2, the primary efficacy endpoint is relative change from baseline in infarct size at 12 months, as assessed by magnetic resonance imaging. The ALLSTAR trial employs a "seamless" WOVE 1 design that enables continuous enrollment from phase 1 to phase 2 and will evaluate the safety of intracoronary administration of allogeneic CDCs and its efficacy in decreasing infarct size in post-MI patients.

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.

Hybrid Coronary Revascularization for the Treatment of Multivessel Coronary Artery Disease: A Multicenter Observational Study.

BACKGROUND: Hybrid coronary revascularization (HCR) combines minimally invasive surgical coronary artery bypass grafting of the left anterior descending artery with percutaneous coronary intervention (PCI) of non-left anterior descending vessels. HCR is increasingly used to treat multivessel coronary artery disease that includes stenoses in the proximal left anterior descending artery and at least 1 other vessel, but its effectiveness has not been rigorously evaluated. OBJECTIVES: This National Institutes of Health-funded, multicenter, observational study was conducted to explore the characteristics and outcomes of patients undergoing clinically indicated HCR and multivessel PCI for hybrid-eligible coronary artery disease, to inform the design of a confirmatory comparative effectiveness trial. METHODS: Over 18 months, 200 HCR and 98 multivessel PCI patients were enrolled at 11 sites. The primary outcome was major adverse cardiac and cerebrovascular events (MACCE) (i.e., death, stroke, myocardial infarction, repeat revascularization) within 12 months post-intervention. Cox proportional hazards models were used to model time to first MACCE event. Propensity scores were used to balance the groups. RESULTS: Mean age was 64.2 ± 11.5 years, 25.5% of patients were female, 38.6% were diabetic, and 4.7% had previous stroke. Thirty-eight percent had 3-vessel coronary artery disease, and the mean SYNTAX (Synergy Between PCI With Taxus and Cardiac Surgery) score was 19.7 ± 9.6. Adjusted for baseline risk, MACCE rates were similar between groups within 12 months post-intervention (hazard ratio [HR]: 1.063; p = 0.80) and during a median 17.6 months of follow-up (HR: 0.868; p = 0.53). CONCLUSIONS: These observational data from this first multicenter study of HCR suggest that there is no significant difference in MACCE rates over 12 months between patients treated with multivessel PCI or HCR, an emerging modality. A randomized trial with long-term outcomes is needed to definitively compare the effectiveness of these 2 revascularization strategies. (Hybrid Revascularization Observational Study; NCT01121263).

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.).

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.).

Management practices and major infections after cardiac surgery.

BACKGROUND: Infections are the most common noncardiac complication after cardiac surgery, but their incidence across a broad range of operations, as well as the management factors that shape infection risk, remain unknown. OBJECTIVES: This study sought to prospectively examine the frequency of post-operative infections and associated mortality, and modifiable management practices predictive of infections within 65 days from cardiac surgery. METHODS: This study enrolled 5,158 patients and analyzed independently adjudicated infections using a competing risk model (with death as the competing event). RESULTS: Nearly 5% of patients experienced major infections. Baseline characteristics associated with increased infection risk included chronic lung disease (hazard ratio [HR]: 1.66; 95% confidence interval [CI]: 1.21 to 2.26), heart failure (HR: 1.47; 95% CI: 1.11 to 1.95), and longer surgery (HR: 1.31; 95% CI: 1.21 to 1.41). Practices associated with reduced infection risk included prophylaxis with second-generation cephalosporins (HR: 0.70; 95% CI: 0.52 to 0.94), whereas post-operative antibiotic duration >48 h (HR: 1.92; 95% CI: 1.28 to 2.88), stress hyperglycemia (HR: 1.32; 95% CI: 1.01 to 1.73); intubation time of 24 to 48 h (HR: 1.49; 95% CI: 1.04 to 2.14); and ventilation >48 h (HR: 2.45; 95% CI: 1.66 to 3.63) were associated with increased risk. HRs for infection were similar with either <24 h or <48 h of antibiotic prophylaxis. There was a significant but differential effect of transfusion by surgery type (excluding left ventricular assist device procedures/transplant) (HR: 1.13; 95% CI: 1.07 to 1.20). Major infections substantially increased mortality (HR: 10.02; 95% CI: 6.12 to 16.39). CONCLUSIONS: Major infections dramatically affect survival and readmissions. Second-generation cephalosporins were strongly associated with reduced major infection risk, but optimal duration of antibiotic prophylaxis requires further study. Given practice variations, considerable opportunities exist for improving outcomes and preventing readmissions. (Management Practices and Risk of Infection Following Cardiac Surgery; NCT01089712).

Mesenchymal precursor cells as adjunctive therapy in recipients of contemporary left ventricular assist devices.

BACKGROUND: Allogeneic mesenchymal precursor cells (MPCs) injected during left ventricular assist device (LVAD) implantation may contribute to myocardial recovery. This trial explores the safety and efficacy of this strategy. METHODS AND RESULTS: In this multicenter, double-blind, sham-procedure controlled trial, 30 patients were randomized (2:1) to intramyocardial injection of 25 million MPCs or medium during LVAD implantation. The primary safety end point was incidence of infectious myocarditis, myocardial rupture, neoplasm, hypersensitivity reaction, and immune sensitization (90 days after randomization). Key efficacy end points were functional status and ventricular function while temporarily weaned from LVAD support (90 days after randomization). Patients were followed up until transplant or 12 months after randomization, whichever came first. Mean age was 57.4 (±13.6) years, mean left ventricular ejection fraction was 18.1%, and 66.7% were destination therapy LVADs. No safety events were observed. Successful temporary LVAD weaning was achieved in 50% of MPC and 20% of control patients at 90 days (P=0.24); the posterior probability that MPCs increased the likelihood of successful weaning was 93%. At 90 days, 3 deaths (30%) occurred in control patients, and none occurred in MPC patients. Mean left ventricular ejection fraction after successful wean was 24.0% (MPC=10) and 22.5% (control=2; P=0.56). At 12 months, 30% of MPC patients and 40% of control patients were successfully temporarily weaned from LVAD support (P=0.69), and 6 deaths (30%) occurred in MPC patients. Donor-specific HLA sensitization developed in 2 MPC and 3 control patients and resolved by 12 months. CONCLUSIONS: In this preliminary trial, administration of MPCs appeared to be safe, and there was a potential signal of efficacy. Future studies will evaluate the potential for higher or additional doses to enhance the ability to wean LVAD recipients off support. CLINICAL TRIAL REGISTRATION URL: http://www.clinicaltrials.gov. Unique identifier: NCT01442129.

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.).

Blood transfusion and infection after cardiac surgery.

Cardiac surgery is the largest consumer of blood products in medicine; although believed life saving, transfusion carries substantial adverse risks. This study characterizes the relationship between transfusion and risk of major infection after cardiac surgery. In all, 5,158 adults were prospectively enrolled to assess infections after cardiac surgery. The most common procedures were isolated coronary artery bypass graft surgery (31%) and isolated valve surgery (30%); 19% were reoperations. Infections were adjudicated by independent infectious disease experts. Multivariable Cox modeling was used to assess the independent effect of blood and platelet transfusions on major infections within 60 ± 5 days of surgery. Red blood cells (RBC) and platelets were transfused in 48% and 31% of patients, respectively. Each RBC unit transfused was associated with a 29% increase in crude risk of major infection (p < 0.001). Among RBC recipients, the most common infections were pneumonia (3.6%) and bloodstream infections (2%). Risk factors for infection included postoperative RBC units transfused, longer duration of surgery, and transplant or ventricular assist device implantation, in addition to chronic obstructive pulmonary disease, heart failure, and elevated preoperative creatinine. Platelet transfusion decreased the risk of infection (p = 0.02). Greater attention to management practices that limit RBC use, including cell salvage, small priming volumes, vacuum-assisted venous return with rapid autologous priming, and ultrafiltration, and preoperative and intraoperative measures to elevate hematocrit could potentially reduce occurrence of major postoperative infections.

Weighting composite endpoints in clinical trials: essential evidence for the heart team.

BACKGROUND: Coronary revascularization trials often use a composite endpoint of major adverse cardiac and cerebrovascular events (MACCE). The usual practice in analyzing data with a composite endpoint is to assign equal weights to each of the individual MACCE elements. Noninferiority margins are used to offset effects of presumably less important components, but their magnitudes are subject to bias. This study describes the relative importance of MACCE elements from a patient perspective. METHODS: A discrete choice experiment was conducted. Survey respondents were presented with a scenario that would make them eligible for the Synergy Between Percutaneous Coronary Intervention With Taxus and Cardiac Surgery (SYNTAX) trial three-vessel disease cohort. Respondents chose among pairs of procedures that differed on the 3-year probability of MACCE, potential for increased longevity, and procedure/recovery time. Conjoint analysis derived relative weights for these attributes. RESULTS: In all, 224 respondents completed the survey. The attributes did not have equal weight. Risk of death was most important (relative weight 0.23), followed by stroke (0.18), potential increased longevity and recovery time (each 0.17), myocardial infarction (0.14), and risk of repeat revascularization (0.11). Applying these weights to the SYNTAX 3-year endpoints resulted in a persistent, but decreased margin of difference in MACCE favoring coronary artery bypass graft surgery compared to percutaneous coronary intervention. When labeled only as "procedure A" and "procedure B," 87% of respondents chose coronary artery bypass graft surgery over percutaneous coronary intervention. When procedures were labeled as "coronary stent" and "coronary bypass surgery," only 73% chose coronary artery bypass graft surgery. Procedural preference varied with demographics, sex, and familiarity with the procedures. CONCLUSIONS: The MACCE elements do not carry equal weight in a composite endpoint, from a patient perspective. Using a weighted composite endpoint increases the validity of statistical analyses and trial conclusions. Patients are subject to bias by labels when considering coronary revascularization.

Design, rationale, and initiation of the Surgical Interventions for Moderate Ischemic Mitral Regurgitation Trial: a report from the Cardiothoracic Surgical Trials Network.

OBJECTIVE: Patients with coronary artery disease complicated by moderate ischemic mitral regurgitation have demonstrably poorer outcome than do patients with coronary artery disease but without mitral regurgitation. The optimal treatment of this condition has become increasingly controversial, and a randomized trial evaluating current practices is warranted. METHODS: We describe the design and initial execution of the Cardiothoracic Surgical Trials Network Surgical Interventions for Moderate Ischemic Mitral Regurgitation Trial. RESULTS: This is an ongoing prospective, multicenter, randomized, controlled clinical trial designed to test the safety and efficacy of mitral repair in addition to coronary artery bypass grafting in the treatment of moderate ischemic mitral regurgitation. CONCLUSIONS: The results of the Cardiothoracic Surgical Trials Network Surgical Interventions for Moderate Ischemic Mitral Regurgitation Trial will provide long-awaited information on controversial therapies for this morbid disease process.

Designing comparative effectiveness trials of surgical ablation for atrial fibrillation: experience of the Cardiothoracic Surgical Trials Network.

OBJECTIVE: Since the introduction of the cut-and-sew Cox maze procedure for atrial fibrillation, there has been substantial innovation in techniques for ablation. Use of alternative energy sources for ablation simplified the procedure and has resulted in dramatic increase in the number of patients with atrial fibrillation treated by surgical ablation. Despite its increasingly widespread adoption, there is lack of rigorous clinical evidence to establish this procedure as an effective clinical therapy. METHODS: This article describes a comparative effectiveness randomized trial, supported by the Cardiothoracic Surgical Clinical Trials Network, of surgical ablation with left atrial appendage closure versus left atrial appendage closure alone in patients with persistent and long-standing persistent atrial fibrillation undergoing mitral valve surgery. Nested within this trial is a further randomized comparison of 2 different lesions sets: pulmonary vein isolation and the full maze lesion set. RESULTS: This article addresses trial design challenges, including how best to characterize the target population, operationalize freedom from atrial fibrillation as a primary end point, account for the impact of antiarrhythmic drugs, and measure and analyze secondary end points, such as postoperative atrial fibrillation load. CONCLUSIONS: This article concludes by discussing how insights that emerge from this trial may affect surgical practice and guide future research in this area.