Total artificial heart implantation as a bridge to transplantation in the United States.

OBJECTIVES: Although the SynCardia total artificial heart (SynCardia Systems, LLC) was approved for use as a bridge to transplantation in 2004 in the United States, most centers do not adopt the total artificial heart as a standard bridging strategy for patients with biventricular failure. This study was designed to characterize the current use and outcomes of patients placed on total artificial heart support. METHODS: The United Network of Organ Sharing Standard Transplant Research File was queried to identify total artificial heart implantation in the United States between 2005 and 2018. Multivariable Cox regression models were used for risk prediction. RESULTS: A total of 471 patients (mean age, 49 years; standard deviation, 13 years; 88% were male) underwent total artificial heart implantation. Of 161 transplant centers, 11 centers had cumulative volume of 10 or more implants. The 6-month cumulative incidence of mortality on the total artificial heart was 24.6%. The 6-month cumulative incidence of transplant was 49.0%. The 1-year mortality post-transplantation was 20.0%. Cumulative center volume less than 10 implants was predictive of both mortality on the total artificial heart (hazard ratio, 2.2, 95% confidence interval, 1.5-3.1, P < .001) and post-transplant mortality after a total artificial heart bridge (hazard ratio, 1.5, 95% confidence interval, 1.0-2.2, P = .039). CONCLUSIONS: Total artificial heart use is low, but the total artificial heart can be an option for biventricular bridge to transplant with acceptable bridge to transplant and post-transplant survival, especially in higher-volume centers. The observation of inferior outcomes in lower-volume centers raises questions as to whether targeted training, center certifications, and minimum volume requirements could improve outcomes for patients requiring the total artificial heart.

Contemporary surgical techniques for mitral valve replacement in extensive mitral annular calcification.

Objectives: Mitral annular calcification remains a formidable lesion in cardiac surgery with significant perioperative morbidity and mortality, particularly when en bloc annular decalcification is implemented. Respect strategies and hybrid approaches have provided safe alternatives. We report the short-term results of our institution's experience with mitral valve replacement in patients with extensive annular calcification. Methods: This is a retrospective review of 72 consecutive patients with extensive annular calcification who underwent open surgical mitral valve replacement from January 1, 2013, to September 31, 2022. Degree of annular calcification was graded as partial, horseshoe, or circumferential. We excluded patients with calcification involving less than one-third of the annulus and patients with rheumatic heart disease. Results: Mean patient age was 71.6 ± 10.9 years, and 50 (69.4%) were female. There were 51 patients (70.8%) with New York Heart Association class 3 or greater and 47 patients (65.3%) with pulmonary hypertension. There were 41 patients (56.9%) with partial, 12 patients (16.7%) with horseshoe, and 19 patients (26.4%) with circumferential calcification. Fifty-six patients (77.8%) underwent conventional valve replacement. Sixteen patients underwent a hybrid procedure using balloon-expandable devices. Concomitant procedures were performed in 61 patients (84.7%). In-hospital mortality and 1-year survival were 3.57% and 82.8% in the standard valve replacement cohort and 25.0% and 54.7% in the hybrid cohort, respectively. Conclusions: Conventional mitral valve replacement using respect strategies is safe and associated with good outcomes in patients with extensive annular calcification. Hybrid approaches using novel devices should remain as a bailout in select patients because of higher perioperative risks and poor short-term outcomes.

Multiple arterial versus single arterial grafting in patients with diabetes undergoing coronary artery bypass surgery.

Background: Data on long-term outcomes in patients with diabetes receiving multiarterial grafting (MAG) versus single-artery grafting (SAG) are limited. Objectives: The objective of this study is to compare long-term outcomes between MAG and SAG for coronary artery bypass graft (CABG) surgery in patients with diabetes. Methods: Patients with diabetes who underwent isolated CABG surgeries between 2000 to 2016 were identified using the New Jersey mandatory state clinical registry linked with death records and hospital discharge data (last follow-up December 31, 2019). Patients who underwent CABG for single-vessel disease, with only venous conduits, patients with previous heart surgeries, or hemodynamically unstable were excluded. Patients undergoing MAG and SAG were matched by propensity score. Cox proportional hazard models were used to investigate long-term survival and competing risk analysis was used for secondary outcomes. Results: Of 24,944 patients, 2955 underwent MAG, and 21,989 underwent SAG CABG. Patients receiving MAG were younger, predominantly men, with a lower prevalence of hypertension, peripheral vascular disease, congestive heart failure, chronic lung disease, and renal failure. MAG was associated with lower long-term mortality compared with SAG in 2882 propensity score-matched pairs (hazard ratio [HR], 0.75; 95% CI, 0.68-0.83); lower risks of repeat revascularization (subdistribution HR, 0.86; 95% CI, 0.76-0.97); and composite outcome defined as death from any cause, stroke, postoperative myocardial infarction, and/or repeat revascularization (HR, 0.76; 95% CI, 0.71-0.82). These results were confirmed in subgroup analyses of women, men, age <70 years, and age ≥70 years patients with diabetes. MAG was also associated with lower mortality compared with SAG in patients with diabetes taking insulin in the entire cohort (Video Abstract). Conclusions: Patients with diabetes benefit from receiving MAG over SAG and demonstrated improved long-term survival, and lower hazards of secondary and composite outcomes. Coordinated efforts are needed to offer MAG to patients with diabetes.

Outcomes of Simultaneous Heart and Kidney Transplantation.

BACKGROUND: Simultaneous heart-kidney transplantation has been increasingly performed in end-stage heart failure patients with concurrent kidney dysfunction despite limited evidence supporting its indications and utility. OBJECTIVES: The purpose of this study was to investigate the effects and utility of simultaneously implanted kidney allografts with various degrees of kidney dysfunction during heart transplantation. METHODS: Using the United Network for Organ Sharing registry, long-term mortality was compared in recipients with kidney dysfunction who underwent heart-kidney transplantation (n = 1,124) vs isolated heart transplantation (n = 12,415) in the United States between 2005 and 2018. In heart-kidney recipients, contralateral kidney recipients were compared for allograft loss. Multivariable Cox regression was used for risk adjustment. RESULTS: Long-term mortality was lower among heart-kidney recipients than among heart-alone recipients when recipients were on dialysis (26.7% vs 38.6% at 5 years; HR: 0.72; 95% CI: 0.58-0.89) or had a glomerular filtration rate (GFR) of <30 mL/min/1.73 m2 (19.3% vs 32.4%; HR: 0.62; 95% CI: 0.46-0.82) and GFR of 30 to 45 mL/min/1.73 m2 (16.2% vs 24.3%; HR: 0.68; 95% CI: 0.48-0.97) but not in GFR of 45 to 60 mL/min/1.73 m2. Interaction analysis showed that the mortality benefit of heart-kidney transplantation continued up to GFR 40 mL/min/1.73 m2. The incidence of kidney allograft loss was higher among heart-kidney recipients than among contralateral kidney recipients (14.7% vs 4.5% at 1 year; HR: 1.7; 95% CI: 1.4-2.1). CONCLUSIONS: Heart-kidney transplantation relative to heart transplantation alone provided superior survival for dialysis-dependent recipients and non-dialysis-dependent recipients up to a GFR of approximately 40 mL/min/1.73 m2 but at the cost of almost twice the risk of kidney allograft loss than contralateral kidney allograft recipients.

Lessons from reoperations for mitral stenosis after mitral valve repair.

BACKGROUND: The durability of mitral valve repair (MVr) is usually defined by the absence of recurrent significant mitral regurgitation. Postrepair mitral stenosis (MS) is a less frequent and less studied mode of failure of MVr. We analyzed our experience in patients who underwent reoperation for postrepair MS to characterize mechanisms resulting in MS and to summarize reoperative surgical strategies and mid-term outcomes. METHODS: Using a prospective database, we retrospectively analyzed data on 35 consecutive patients who underwent reoperation for symptomatic moderate to severe MS between January 1, 2011, and February 1, 2020. RESULTS: The mean patient age was 61.4 ± 11.4 years, and 69% were female. The median annuloplasty ring size used at the initial repair was 28 mm (interquartile range, 26-30 mm). Additional repair techniques at the initial operation included leaflet resection in 12 patients (34%) and commissuroplasty or edge-to-edge repair in 6 patients (18%). At reoperation, the most common mechanism of MS was pannus ingrowth in 20 patients (57%), leaflet calcification in 12 (34%), commissural fusion in 5 (14%), and tunnel effect (functional MS) in 3 (9%). Twenty-two patients (63%) underwent valve replacement, and 13 (37%) underwent valve re-repair. In patients who underwent re-repair, annuloplasty revision was performed in all patients, with 6 patients (46%) converted from complete ring to band, 4 (11%) converted from ring to pericardial annuloplasty, 2 (6%) converted to no annuloplasty, and 1 (8%) with annuloplasty ring upsizing. There were no in-hospital or 1-year mortalities. Survival at the 5-year follow-up was 93.9%. CONCLUSIONS: MS causing late failure of MVr is frequently associated with smaller ring sizes and inflammatory or calcific changes in the valve. Highly selected patients may be good candidates for mitral valve re-repair.

Type-A Aortic Dissection and Cerebral Perfusion: The Society of Thoracic Surgeons Database Analysis.

BACKGROUND: The optimal cerebral perfusion strategy during hypothermic circulatory arrest for acute type A aortic dissection repair is controversial. This study used a national clinical registry to evaluate cerebral protection strategies. METHODS: Using the Society of Thoracic Surgeons Adult Cardiac Surgical Database, study investigators identified 6387 patients with aortic dissection (mean age, 60.4 years, SD 13.5 years) who underwent total arch (n = 872; 13.7%) or ascending or hemiarch (n = 5515; 86.3%) replacement with circulatory arrest between 2014 and 2016 in the United States. Multivariable analysis adjusted for potential confounders, including demographics and comorbidity. Outcomes were compared according to the following: use of retrograde, antegrade, or no cerebral perfusion; nadir temperature; and duration of circulatory arrest. The primary end point was a composite of 30-day and in-hospital mortality or stroke. RESULTS: The rate of death or stroke was 25.5% (n = 1627). Antegrade cerebral perfusion was used in 46.2% (n = 2950) patients, retrograde cerebral perfusion was used in 22.6% (n = 1445), and no cerebral perfusion was used in 31.2% (n = 1992). In multivariable analysis, death or stroke risk increased with longer circulatory arrest duration (adds ratio [OR], 1.11 per 10-minute increment; 95% confidence interval [CI], 1.08 to 1.14). Multivariate analysis stratified by temperature showed improved outcomes with cerebral perfusion (antegrade or retrograde) and deep (OR, 0.86; 95% CI, 0.74 to 0.98), or moderate (OR, 0.78; 95% CI, 0.65 to 0.95) hypothermic circulatory arrest vs circulatory arrest without cerebral perfusion. There was a slight correlation between nadir temperature and the primary outcome. CONCLUSIONS: Cerebral perfusion should be used during arch repair for aortic dissection because antegrade and retrograde cerebral perfusion strategies are associated with reduced death and stroke risk compared with hypothermic circulatory arrest without cerebral perfusion.

Impact of Cerebral Perfusion on Outcomes of Aortic Surgery: The Society of Thoracic Surgeons Adult Cardiac Surgery Database Analysis.

BACKGROUND: Limited data inform cerebral protection during circulatory arrest. This study was designed to identify optimal approaches from a national clinical registry. METHODS: A total of 7830 adults (mean age, 63.1 years, SD 13.1 years) who underwent hemiarch (n = 6891; 88.0%) or total arch (n = 939; 12.0%) replacement with hypothermic circulatory arrest between 2014 and 2016 were identified from The Society of Thoracic Surgeons Adult Cardiac Surgery Database (version 2.81). Aortic dissections were excluded from the analysis. Multivariable logistic regression was used to adjust for 29 baseline and operative variables, including demographics, comorbidity, surgery, and nadir temperature, comparing outcomes according to protection strategy. The primary end point was a composite of 30-day and in-hospital mortality or major permanent neurologic complications. RESULTS: The rate of death or permanent neurologic complication was 10.9% (n = 850). Antegrade cerebral perfusion was most commonly used (n = 3369; 43%; median nadir temperature 23°C; median arrest time 30 minutes) compared with retrograde cerebral perfusion (n = 1898; 24%; 20°C; 24 minutes) and no cerebral perfusion (n = 2563; 33%; 20°C, 22 minutes). In multivariable analysis, deep hypothermia with antegrade (odds ratio [OR], 0.65; 95% confidence interval [CI], 0.52 to 0.81) or retrograde (OR, 0.57; 95% CI, 0.45 to 0.71) perfusion and moderate hypothermia with antegrade perfusion (OR, 0.61; 95% CI, 0.46 to 0.79) were associated with significant reductions in death and stroke compared with deep hypothermia without cerebral perfusion. Risk reduction was greatest in circulatory arrest lasting longer than 30 minutes. CONCLUSIONS: For patients without aortic dissection and who require more than 30 minutes of circulatory arrest, optimal cerebral protection strategies are deep hypothermia with either antegrade or retrograde cerebral perfusion and moderate hypothermia with antegrade cerebral perfusion.

Second crossclamp to perfect degenerative mitral valve repair: Decision-making algorithm, safety, and outcomes.

OBJECTIVES: Residual mitral regurgitation reduces the efficacy of mitral repair and is associated with worse outcomes. We adopted a policy using a second bypass run for patients with residual mitral regurgitation (>+1) and described our decision-making algorithm and outcomes. METHODS: From January 1, 2011, to December 31, 2016, 40 patients with degenerative disease underwent a second bypass run to address residual mitral regurgitation. The echocardiographic criteria for a second bypass run was the presence of moderate or greater mitral regurgitation or mild mitral regurgitation with unfavorable mechanism. RESULTS: A second bypass run was used in 40 patients. The mean age was 57.3 ± 13.5 years (21-79 years), and 14 patients (35%) were asymptomatic. Residual mitral regurgitation was mild in 25 patients, moderate in 9 patients, and moderate/severe in 6 patients. The cause of postbypass mitral regurgitation was technical or residual pathology in 35 patients and systolic anterior motion in 5 patients. Re-repair techniques were cleft closure in 22 patients, primary suture repair in 13 patients, and expanded polytetrafluoroethylene chordoplasty in 9 patients. After re-repair, 34 patients (85%) had no mitral regurgitation, 4 patients (10%) had trace mitral regurgitation, and 2 patients (5%) had mild mitral regurgitation. Median total cardiopulmonary bypass time was 208.5 minutes, first crossclamp time was 106 minutes, and second crossclamp time was 34 ± 12 minutes. Median intensive care stay was 2 days, and hospital stay was 8 days. On discharge, there was no mitral regurgitation in 13 patients (33%), trace in 23 patients (58%), and mild mitral regurgitation in 4 patients (10%). Freedom from moderate or greater mitral regurgitation at 5 years was 100%. CONCLUSIONS: Residual mitral regurgitation can be effectively treated using a second bypass run with good long-term outcome and minimal incremental risk.

Outcomes of Second Arterial Conduits in Patients Undergoing Multivessel Coronary Artery Bypass Graft Surgery.

BACKGROUND: Benefits of multiarterial versus single-arterial coronary bypass grafting (CABG) are debated. OBJECTIVES: This study sought to compare long-term survival, morbidity, and graft patency after multiarterial versus single-arterial CABG. METHODS: Mandatory clinical registries linked with discharge databases were used to identify baseline and operative characteristics and outcomes of 42,714 patients undergoing CABG from 2005 through 2012. Patients with single-vessel disease, without arterial conduits, or undergoing emergency, reoperative, or concomitant procedures were excluded. Survival, stroke, myocardial infarction, and repeat revascularization rates were compared using Cox modeling, and patients were matched by propensity score. Median follow-up was 7.8 years (interquartile range: 5 to 10 years); last follow-up was December 31, 2016. RESULTS: Of the 26,124 patients, 3,647 (14.0%) underwent multiarterial CABG. Single-arterial CABG patients were older (mean 68 vs. 61 years; p < 0.001), had more comorbidities, and received fewer bypass grafts (3.4 vs. 3.6; p < 0.001). After adjusting for baseline differences, multiarterial CABG was associated with lower 10-year mortality compared with single-arterial CABG in 3,588 propensity-matched pairs (15.1% vs. 17.3%; p = 0.01). Multiarterial CABG was associated with lower 10-year myocardial infarction (hazard ratio: 0.81; 95% confidence interval: 0.69 to 0.95) and lower 10-year reintervention rate (hazard ratio: 0.81; 95% confidence interval: 0.67 to 0.99). CONCLUSIONS: In contemporary practice, single-arterial CABG is used in 85% of patients and is associated with increased long-term mortality, myocardial infarction, and reintervention compared with multiarterial CABG. Multiarterial CABG is underused in contemporary surgical revascularization, and targeted referral of younger patients for multiarterial revascularization may address this practice gap.