Steve K. Singh

Tricuspid Valve Repair With an Annuloplasty Ring Results in Improved Long-Term Outcomes

Background— The purpose of this study was to compare the long-term results of tricuspid valve (TV) repair with or without an annuloplasty ring. Methods and Results— 702 patients underwent TV repair at our institution (1978 to 2003), of which 493 had, predominantly, a De Vega procedure (no ring) and 209 had an annuloplasty ring (ring). TV pathology was functional (secondary) in 74% of patients. Concomitant procedures consisted of mitral valve surgery in 80% of patients, aortic valve surgery in 33%, and coronary bypass in 14%. Clinical and echocardiographic follow-up data were obtained. Follow-up was 99% complete and was 5.9±4.9 (mean±SD) years long. Ring patients were younger (55±14 versus 59±14 years; P=0.001) and less likely to have coronary artery disease (10% versus 17%; P=0.02), more likely to be female (75% versus 65%; P=0.01) and having had previous cardiac surgery (56% versus 42%; P=0.001). Operative times were similar between the 2 groups. Long-term survival, event-free survival and freedom from recurrent TR were significantly better in the ring group, and there was a trend toward fewer TV reoperations. Multivariable analysis demonstrated that the use of an annuloplasty ring was an independent predictor of long-term survival (hazard ratio [HR], 0.7; 95% confidence interval [CI], 0.5 to 1.0; P=0.03) and event-free survival (HR, 0.8; CI, 0.6 to 1.0; P=0.04). Conclusions— Placement of an annuloplasty ring in patients undergoing tricuspid valve repair is associated with improved survival and event-free survival.

Effects of Cardiac Resynchronization Therapy With or Without a Defibrillator on Survival and Hospitalizations in Patients With New York Heart Association Class IV Heart Failure

Background— Cardiac resynchronization therapy (CRT) alone or combined with an implantable defibrillator (CRT-D) has been shown to improve exercise capacity and quality of life and to reduce heart failure (HF) hospitalizations and mortality in patients with New York Heart Association (NYHA) class III and IV HF. There is concern that the device procedure may destabilize these very ill class IV patients. We sought to examine the outcomes of NYHA class IV patients enrolled in the Comparison of Medical Therapy, Pacing, and Defibrillation in Heart Failure (COMPANION) trial to assess the potential benefits of CRT and CRT-D. Methods and Results— The COMPANION trial randomized 1520 patients with NYHA class III and IV HF to optimal medical therapy, CRT, or CRT-D. In the class IV patients (n=217), the primary end point of time to death or hospitalization for any cause was significantly improved by both CRT (hazard ratio [HR], 0.64; 95% CI, 0.43 to 0.94; P=0.02) and CRT-D (HR, 0.62; 95% CI, 0.42 to 0.90; P=0.01). Time to all-cause death and HF hospitalization was also significantly improved in both CRT (HR, 0.57; 95% CI, 0.37 to 0.87; P=0.01) and CRT-D (HR, 0.49; 95% CI, 0.32 to 0.75; P=0.001) Time to all-cause death trended to an improvement in both CRT (HR, 0.67; 95% CI, 0.41 to 1.10; P=0.11) and CRT-D (HR, 0.63; 95% CI, 0.39 to 1.03; P=0.06). Time to sudden death appeared to be significantly reduced in the CRT-D group (HR, 0.27; 95% CI, 0.08 to 0.90; P=0.03). There was a nonsignificant reduction in time to HF deaths for both CRT (HR, 0.68; 95% CI, 0.34 to 1.37; P=0.28) and CRT-D (HR, 0.79; 95% CI, 0.41 to 1.52; P=0.48). Conclusions— CRT and CRT-D significantly improve time to all-cause mortality and hospitalizations in NYHA class IV patients, with a trend for improved mortality. These devices should be considered in ambulatory NYHA class IV HF patients similar to those enrolled in COMPANION.

Troponin after cardiac surgery: a predictor or a phenomenon?

BACKGROUND Increased cardiac troponin is observed after virtually every cardiac operation, indicating perioperative myocardial injury. The clinical significance of this elevation is controversial. This study aimed to correlate postoperative troponin levels with major adverse cardiac events (MACE). METHODS The study included 1918 consecutive patients undergoing adult cardiac operations, including 1515 isolated coronary procedures, 229 valvular operations, and 174 combined coronary/valve procedures. Peak troponin T (normal value < 0.1 microg/L) was measured at less than 24 hours postoperatively. Excluded were 506 patients with a recent myocardial infarction (< 30-days of operation). The primary outcome was a composite of death, electrocardiogram-defined infarction, and low output syndrome (MACE). RESULTS Mortality rates were 1.4%, 6.1%, and 7% in the coronary bypass, valve, and combined groups, respectively (p < 0.001). The rates of MACE were 17%, 35%, and 44% (p < 0.0001), and mean troponin T levels were 0.9 +/- 1.5, 1.2 +/- 2.9, and 1.3 +/- 1.2 microg/L (p < 0.001), in the coronary bypass, valve, and combined groups, respectively. All patients were divided into quintiles based on their peak postoperative troponin level (Q1, 0.0 to 0.39; Q2, 0.4 to 0.59; Q3, 0.6 to 0.79; Q4, 0.8 to 1.29; and Q5, > 1.3 microg/L). Adverse outcomes were similar and stable in the lower quintiles. A stepwise increase in adverse outcomes was observed in the higher quintiles. Receiver operating characteristic curve analysis revealed a troponin cutoff of 0.8 microg/L was the most discriminatory for MACE (area under the curve, 0.7). Multivariable analyses showed a troponin value of more than 0.8 microg/L was independently associated with MACE. CONCLUSIONS Moderate elevations in troponin are common after cardiac operations; troponin is a well-described predictor of outcomes. Troponin levels exceeding 0.8 microg/L are associated with increased MACE in patients without a history of preoperative myocardial infarction within 30 days of operation.

The Impact of Diabetic Status on Coronary Artery Bypass Graft Patency Insights From the Radial Artery Patency Study

Background‐ Despite worse outcomes in diabetics after coronary artery bypass grafting surgery, studies have not examined graft patency in this high-risk group. This study examined the impact of diabetes on graft patency, 1-year postcoronary artery bypass grafting, using data from a multicenter randomized trial. Methods and Results‐ The Radial Artery Patency Study enrolled 561 patients undergoing coronary artery bypass grafting, comparing graft patency of the saphenous vein (SV) versus radial artery 1-year postcoronary artery bypass grafting. Angiographic follow-up was acquired for 440 patients (115 diabetics, 325 nondiabetics), each with a study radial artery and a control SV graft. Preoperative characteristics were similar. The proportion of small-sized target vessels was greater in diabetics (P=0.04). At 1 year, 33 of 230 study grafts (14.4%) were occluded in the diabetics versus 63 of 650 (9.7%) in the nondiabetics (P=0.052). Multivariable regression found diabetes to be a significant independent predictor of 1-year graft occlusion (relative risk, 1.45; 95% CI, 1.03 to 2.05; P=0.03) along with female gender, SV conduit, and small target-vessel size. A significantly higher proportion of SV grafts were occluded in the diabetics (19% versus 12%, P=0.04). Radial artery grafting was protective in the diabetic cohort (radial artery: 11 of 115 occluded [9.5%] versus SV: 22 of 115 occluded [19.1%], McNemar corrected P=0.05; relative risk, 0.42; 95% CI, 0.16 to 1.01) and nondiabetics (radial artery: 25 of 325 occluded [7.7%] versus SV: 38 of 325 occluded [11.7%], McNemar corrected P=0.11; relative risk, 0.63; 95% CI, 0.35 to 1.10). Conclusions‐ Coronary artery bypass grafting occlusions were more common among diabetics versus nondiabetics at 1-year angiography, mainly because of more frequent SV graft failure in diabetics. Radial artery, compared with SV grafting, is protective in both diabetic and nondiabetic patients.

Acute and Long‐Term Outcomes of Catheter Ablation of Atrial Fibrillation Using the Second‐Generation Cryoballoon versus Open‐Irrigated Radiofrequency: A Multicenter Experience

There are limited comparative data on catheter ablation of atrial fibrillation (CAAF) using the second‐generation cryoballoon (CB‐2) versus point‐by‐point radiofrequency (RF). This study examines the acute/long‐term CAAF outcomes using these 2 strategies.

Single- vs Double-Lung Transplantation in Patients With Chronic Obstructive Pulmonary Disease and Idiopathic Pulmonary Fibrosis Since the Implementation of Lung Allocation Based on Medical Need

IMPORTANCE Outcomes of single- and double-lung transplantation have not been rigorously assessed since the allocation of donor lungs according to medical need as quantified by the Lung Allocation Score, which began in 2005. OBJECTIVE To compare outcomes in single- and double-lung transplant recipients since the Lung Allocation Score was implemented. DESIGN, SETTING, AND PARTICIPANTS In this exploratory analysis, adults with idiopathic pulmonary fibrosis (IPF) or chronic obstructive pulmonary disease (COPD) who underwent lung transplantation in the United States between May 4, 2005, and December 31, 2012, were identified in the United Network for Organ Sharing thoracic registry, with follow-up to December 31, 2012. Posttransplantation graft survival was assessed with Kaplan-Meier analysis. Propensity scores were used to control for treatment selection bias. A multivariable flexible parametric prognostic model was used to characterize the time-varying hazard associated with single- vs double-lung transplantation. EXPOSURE Single- or double-lung transplantation. MAIN OUTCOMES AND MEASURES Composite of posttransplant death and graft failure (retransplantation). RESULTS Patients with IPF (n = 4134, of whom 2010 underwent single-lung and 2124 underwent double-lung transplantation) or COPD (n = 3174, of whom 1299 underwent single-lung and 1875 underwent double-lung transplantation) were identified as having undergone lung transplantation since May 2005. Median follow-up was 23.5 months. Of the patients with IPF, 1380 (33.4%) died and 115 (2.8%) underwent retransplantation; of the patients with COPD, 1138 (34.0%) died and 59 (1.9%) underwent retransplantation. After confounders were controlled for with propensity score analysis, double-lung transplants were associated with better graft survival in patients with IPF (adjusted median survival, 65.2 months [interquartile range {IQR}, 21.4-91.3 months] vs 50.4 months [IQR, 17.0-87.5 months]; P < .001) but not in patients with COPD (adjusted median survival, 67.7 months [IQR, 25.2-89.6 months] vs 64.0 months [IQR, 25.2-88.7 months]; P = .23). The interaction between diagnosis type (COPD or IPF) and graft failure was significant (P = .049). Double-lung transplants had a time-varying association with graft survival; a decreased instantaneous late hazard for death or graft failure among patients with IPF was noted at 1 year and persisted at 5 years postoperatively (instantaneous hazard at 5 years, hazard ratio, 0.67 [95% CI, 0.52-0.84] in patients with IPF and 0.89 [95% CI, 0.71-1.13] in patients with COPD). CONCLUSIONS AND RELEVANCE In an exploratory analysis of registry data since implementation of a medical need-based lung allocation system, double-lung transplantation was associated with better graft survival than single-lung transplantation in patients with IPF. In patients with COPD, there was no survival difference between single- and double-lung transplant recipients at 5 years.

Early extubation after pediatric cardiac surgery: systematic review, meta-analysis, and evidence-based recommendations

Abstract  Objective: To derive evidence‐based recommendations regarding early extubation strategy after congenital cardiac surgery. Outcomes: Incidence of total mortality, morbidity, reintubation, length, and costs of intensive care unit and hospital stay. Evidence: Medline, Embase, and the Cochrane‐controlled trial register on the Cochrane library were searched from the earliest achievable date of each database to present. No language restrictions were applied. Retrieved reprints were evaluated according to a priori inclusion criteria, and those included were critically appraised using established internal validity criteria. Benefits and Harms: Early extubation (in the operating room or ≤6 hours after surgery) was associated with a lower early mortality. There was a trend toward lower ICU and hospital length of stays, lower hospital costs, and less respiratory morbidity. There was no difference in the rate of reintubation in those extubated early versus late. Conclusion: Early extubation appears safe and is associated with reduction in length of ICU and hospital stay without adverse effects on mortality or morbidity. However, studies to date are poor, heterogeneous, and not suitable to determine a causal effect. Therefore, there is need for a well‐designed randomized clinical trial to demonstrate the potential significant benefits of early extubation. (J Card Surg 2010;25:586‐595)

Association between incomplete surgical ligation of left atrial appendage and stroke and systemic embolization.

BACKGROUND Surgical exclusion of the left atrial appendage (LAA) can frequently yield incomplete closure. OBJECTIVE We evaluated the ischemic stroke/systemic embolization (SSE) risk in patients with atrial fibrillation (AF) and complete LAA closure (cLAA) vs incompletely surgically ligated LAA (ISLL) and LAA stump after surgical suture ligation. METHODS Seventy-two patients (CHA2DS2-VASc score 4.1 ± 1.9) underwent surgical LAA ligation in conjunction with mitral valve/AF surgery and postoperative LAA evaluation using computerized tomographic angiography. RESULTS Overall, cLAA was detected in 46 of 72 patients (64%), ISLL in 17 patients (24%), and LAA stump in 9 patients (12%). The incidences of oral anticoagulation (OAC) and recurrent AF were similar among the 3 groups during 44 ± 19 months of follow-up. SSE occurred in 2% of patients with cLAA vs 24% with ISLL and 0% with LAA stump (P = .006). None of the patients with SSE were receiving OAC, and all had recurrent AF during follow-up. Additionally, patients with SSE exhibited a significantly smaller ISLL neck diameter (2.8 ± 1.0 vs 7.1 ± 2.1 mm; P = .002). The annualized SSE risk was 1.9% (entire cohort), 6.5% (ISLL patients), 14.4% (ISLL patients not receiving OAC), and 19.0% (ISLL neck diameter ≤5.0 mm) per 100 patient-years of follow-up. The latter risk was nearly 5 times greater than predicted by conventional risk-stratification schemes. Moreover, ISLL emerged as an independent predictor of SSE in univariate analyses and as the sole predictor of SSE in a multivariate analysis. CONCLUSION In patients with AF, ISLL is a predictor of SSE, independent of conventional risk stratification schemes. Consequently, OAC should be strongly considered in this high-risk cohort.

The long-term impact of diabetes on graft patency after coronary artery bypass grafting surgery: A substudy of the multicenter Radial Artery Patency Study

OBJECTIVES The study objective was to determine the impact of diabetes on radial artery and saphenous vein graft occlusion and clinical outcomes more than 5 years after coronary artery bypass surgery in the multicenter Radial Artery Patency Study (NCT00187356). METHODS A total of 529 patients aged less than 80 years with triple-vessel disease undergoing coronary bypass surgery participated in this study. Angiographic follow-up occurred more than 5 years after surgery with annual clinical follow-up. The primary objective was to compare the proportion of complete graft occlusion between radial artery and saphenous vein grafts among diabetic and nondiabetic persons. Additional objectives included determining predictors of complete graft occlusion and comparison of major adverse cardiac events defined by cardiac death, late myocardial infarction, and reintervention. RESULTS There were 148 of 529 patients (27.8%) with diabetes; 269 patients (83/269 [30.9%] diabetic) underwent late angiography at mean of 7.7±1.5 years after surgery. In diabetic patients, the proportion of complete graft occlusion was significantly lower in the radial grafts (4/83 [4.8%]) than in the saphenous grafts (21/83 [25.3%]) (P=.0004), and this was similar in nondiabetic patients (P=.19). Multivariate modeling showed that the use of the radial artery and high-grade target vessel stenosis were protective against late graft occlusion, whereas female gender, smoking history, and elevated creatinine were associated with an increased risk; interaction between diabetic status and conduit type also was significant (P=.02). Major adverse cardiac events were higher in diabetic patients (23/148 [15.5%] vs 35/381 [9.2%], P=.04). CONCLUSIONS The use of the radial artery should be strongly considered in diabetic patients undergoing coronary bypass surgery, especially with high-grade target vessel stenosis.

Transplantation for Idiopathic Pulmonary Arterial Hypertension: Improvement in the Lung Allocation Score Era

Background— Lung transplantation and heart-lung transplantation represent surgical options for treatment of medically refractory idiopathic pulmonary arterial hypertension. The effect of the lung allocation score on wait-list and transplantation outcomes in patients with idiopathic pulmonary arterial hypertension is poorly described. Methods and Results— Adults diagnosed with idiopathic pulmonary arterial hypertension and listed for transplantation in the 80 months before and after the lung allocation score algorithm was implemented (n=1430) were identified in the United Network for Organ Sharing thoracic registry. Patients were stratified by organ listed and pre– and post–lung allocation score era. The cumulative incidences of transplantation and mortality for wait-listed patients in both eras were appraised with competing outcomes analysis. Posttransplantation survival was assessed with the Kaplan-Meier method. These analyses were repeated in propensity-matched subgroups. Cox proportional hazards analysis evaluated the effect of prelisting and pretransplantation characteristics on mortality. We found that patients in the post–lung allocation score era had significantly worse comorbidities; nevertheless, both lung transplantation and heart-lung transplantation candidates in this era enjoyed lower wait-list mortality and a higher incidence of transplantation in unmatched and propensity-matched analyses. On multivariable analysis, heart-lung transplantation and double-lung transplantation were associated with improved survival from the time of wait-listing, as was being listed at a medium- to high-volume institution. Donor/recipient sex matching predicted posttransplantation survival. Conclusions— The incidence of transplantation has increased while wait-list mortality has decreased in patients with idiopathic pulmonary arterial hypertension wait-listed for transplantation in the post–lung allocation score era. Both heart-lung transplantation and double-lung transplantation are predictive of survival in transplantation candidates with idiopathic pulmonary arterial hypertension, as is being listed at a medium- to high-volume institution. Donor/recipient sex matching is associated with better posttransplantation survival. # Clinical Perspective {#article-title-47}Background— Lung transplantation and heart-lung transplantation represent surgical options for treatment of medically refractory idiopathic pulmonary arterial hypertension. The effect of the lung allocation score on wait-list and transplantation outcomes in patients with idiopathic pulmonary arterial hypertension is poorly described. Methods and Results— Adults diagnosed with idiopathic pulmonary arterial hypertension and listed for transplantation in the 80 months before and after the lung allocation score algorithm was implemented (n=1430) were identified in the United Network for Organ Sharing thoracic registry. Patients were stratified by organ listed and pre– and post–lung allocation score era. The cumulative incidences of transplantation and mortality for wait-listed patients in both eras were appraised with competing outcomes analysis. Posttransplantation survival was assessed with the Kaplan-Meier method. These analyses were repeated in propensity-matched subgroups. Cox proportional hazards analysis evaluated the effect of prelisting and pretransplantation characteristics on mortality. We found that patients in the post–lung allocation score era had significantly worse comorbidities; nevertheless, both lung transplantation and heart-lung transplantation candidates in this era enjoyed lower wait-list mortality and a higher incidence of transplantation in unmatched and propensity-matched analyses. On multivariable analysis, heart-lung transplantation and double-lung transplantation were associated with improved survival from the time of wait-listing, as was being listed at a medium- to high-volume institution. Donor/recipient sex matching predicted posttransplantation survival. Conclusions— The incidence of transplantation has increased while wait-list mortality has decreased in patients with idiopathic pulmonary arterial hypertension wait-listed for transplantation in the post–lung allocation score era. Both heart-lung transplantation and double-lung transplantation are predictive of survival in transplantation candidates with idiopathic pulmonary arterial hypertension, as is being listed at a medium- to high-volume institution. Donor/recipient sex matching is associated with better posttransplantation survival.