Blood type O heart transplant candidates have longer waitlist time and higher delisting under the new allocation system.

OBJECTIVE: Prior studies have examined the effect of blood type on heart transplantation (HTx) waitlist outcomes in cohorts through 2015. We aim to analyze the effect of blood type on contemporary waitlist outcomes with a new allocation system focus. METHODS: Adults listed for HTx between April 2015 and December 2020 were included. Survival to HTx and waitlist death/deterioration was compared between type O and non-type O candidates using competing risks regression. Donor/recipient ABO compatibility trends were further investigated. RESULTS: Candidates with blood type O (n = 7509) underwent HTx less frequently than candidates with blood type other than type O (n = 9699) (subhazard ratio [sHR], 0.56; 95% CI, 0.53-0.58) with higher rates of waitlist death/deterioration (sHR, 1.18; 95% CI, 1.04-1.34). Subgroup analyses demonstrated persistence of this trend under the new donor heart allocation system (HTx: sHR, 0.58; 95% CI, 0.54-0.62; death/clinical deterioration: sHR, 1.27; 95% CI, 1.02-1.60), especially among those listed at high status (1, 2, or 3) (HTx: sHR, 0.69; 95% CI, 0.63-0.75; death/deterioration: sHR, 1.61; 95% CI, 1.16-2.22). Among those listed at status 3, waitlist death/deterioration was modified by presence of a durable left ventricular assist device (left ventricular assist device: sHR, 1.57; 95% CI, 0.58-4.29; no left ventricular assist device: sHR, 3.79; 95% CI, 1.28-11.2). Type O donor heart allocation to secondary ABO candidates increased in the new system (14.5% vs 12.0%; P < .01); post-HTx survival remained comparable between recipients with blood type O and non-type O (log-rank P = .07). CONCLUSIONS: Further logistical considerations are warranted to minimize allocation inequity regarding blood type under the new allocation system.

Heart Transplant Waitlist Outcomes and Wait Time by Center Volume in the Pre-2018 Allocation Change Era.

Although the transplant outcomes of centers are heavily monitored and compared, with a particular link between posttransplant outcomes and center volume demonstrated, little data exist comparing waitlist outcomes. Here, we explored waitlist outcomes by transplant center volume. We performed a retrospective analysis of adults listed for primary heart transplantation (HTx) from 2008 to 2018 using the United Network for Organ Sharing database. Transplant centers were split into low (<10 HTx/year), medium (10-30 HTx/year), and high (>30 HTx/year) volume, and waitlist outcomes were compared. Of the 35,190 patients included in our study, 23,726 (67.4%) underwent HTx, 4,915 (14.0%) died or deteriorated before receiving HTx, 1,356 (3.9%) were delisted due to recovery, and 1,336 (3.8%) underwent left ventricular assist device (LVAD) implantation. High-volume centers had higher rates of survival to transplant (71.3% vs. 60.6% for low-volume centers and 64.9% for medium-volume centers), and low rates of death or deterioration (12.6% vs. 14.6% for low-volume centers and 15.1% for medium-volume centers). Listing at a low-volume center was independently associated with death or delisting before HTx (HR 1.18, p = 0.007), whereas listing at a high-volume center (HR 0.86; p < 0.001) and prelisting LVAD (HR 0.67, p < 0.001) were protective. Death or delisting before HTx was lowest for patients listed in higher volume centers.

Total ventricular mass oversizing +50% or greater was a predictor of worse 1-year survival after heart transplantation.

OBJECTIVES: Current donor-recipient size matching guidelines rely primarily on body weight, with no specified oversizing cutoff values. Recent literature has explored predicted total ventricular mass matching over body weight matching. We aim to explore the impact of total ventricular mass oversizing on heart transplant outcomes. METHODS: The United Network for Organ Sharing database was queried for adults who underwent primary heart transplant from 1997 to 2017. By using validated equations, donor-recipient total ventricular mass mismatch was calculated. Donor-recipient pairs were divided into 3 groups by total ventricular mass mismatch. Post-heart transplant 1-year survival was analyzed using the Kaplan-Meier method and Cox proportional hazards models. We also investigated post-heart transplant complications, independent predictors for mortality, donor-recipient sex mismatch, and donor-recipient body habitus in total ventricular mass mismatch greater than +50%. RESULTS: A total of 34,455 donor-recipient pairs were included. Fractional polynomial regression demonstrated increased the risk of mortality with higher total ventricular mass mismatch. Total ventricular mass mismatch of +48.3% maximized the Youden Index. Donor-recipient pairs were subsequently grouped by total ventricular mass mismatch as -20% to +30%, +30% to +50%, and greater than +50%. Total ventricular mass mismatch greater than +50% was an independent risk factor for 1-year mortality (hazard ratio, 1.40, P = .004) and was associated with increased postoperative stroke (P = .002). Some 80.3% of these recipients were smaller female patients with male donors. Total ventricular mass mismatch from +30% to +50% was not associated with worse survival (P = .17). CONCLUSIONS: Total ventricular mass mismatch greater than +50% is associated with worse 1-year survival, although this group comprises a small portion of heart transplant. total ventricular mass mismatch from +30% to +50% is not associated with worse survival. These outcomes should be considered in selecting donors and in efforts to expand the potential donor pool.

Trends in Outcomes of Heart Transplants Using Extended Criteria Donors: A United Network for Organ Sharing Database Analysis.

BACKGROUND: Although the use of extended criteria donors (ECDs) is traditionally avoided because of poorer outcomes, management of heart transplant (HTx) recipients has evolved over the past decades. We sought to examine the temporal trends in outcomes of ECDs in HTx. METHODS: We queried the United Network for Organ Sharing database for adult HTx recipients who fit the EXPAND Trial criteria for ECDs: ischemic time ≥ 4 hours, ejection fraction < 50%, age > 55 years, and history of coronary artery disease. Transplant years were stratified into the following 4 periods: (1) 2000 to 2004, (2) 2005 to 2009, (3) 2010 to 2014, and (4) 2014 to 2018. The 2-sample t test, Kaplan-Meier survival analysis, log-rank test, analysis of variance, multivariable Cox proportional hazards, and multinomial logistic regression were used to compare data between periods. RESULTS: Through periods 1 to 4, 39,028 patients were stratified as follows: 9217 (2942 ECDs, 31.9%), 9224 (2730 ECDs, 29.6%), 10,309 (2762 ECDs, 26.8%), and 10,278 (2190 ECDs, 21.3%). Transplants using ECDs in periods 1 and 2 had increased 1-year mortality compared with periods 3 and 4 (16.9% and 15.6% vs 11.9% and 10.9% respectively, P < .001). Later periods also demonstrated improved Karnofsky scores (P < .001). CONCLUSIONS: Although use of ECDs decreased across the periods, we noted significant improvement in 1-year survival rates and postoperative functional status.

Environmental oxygen affects ex vivo growth and proliferation of mesenchymal progenitors by modulating mitogen-activated protein kinase and mammalian target of rapamycin signaling.

BACKGROUND AIMS: Stem and progenitor cells of hematopoietic and mesenchymal lineages reside in the bone marrow under low oxygen (O2) saturation. O2 levels used in ex vivo expansion of multipotent mesenchymal stromal cells (MSCs) affect proliferation, metabolism and differentiation. METHODS: Using cell-based assays and transcriptome and proteome data, the authors compared MSC cultures simultaneously grown under a conventional 19.95% O2 atmosphere or at 5% O2. RESULTS: In 5% O2, MSCs showed better proliferation and higher self-renewal ability, most probably sustained by enhanced signaling activity of mitogen-activated protein kinase and mammalian target of rapamycin pathways. Non-oxidative glycolysis-based energy metabolism supported growth and proliferation in 5% O2 cultures, whereas MSCs grown under 19.95% O2 also utilized oxidative phosphorylation. Cytoprotection mechanisms used by cells under 5% O2 differed from 19.95% O2  suggesting differences in the triggers of cell stress between these two O2  conditions. CONCLUSIONS: Based on the potential benefits for the growth and metabolism of MSCs, the authors propose the use of 5% O2 for MSC culture.

Geographic Variation in Heart Transplant Extended Criteria Donors in the United States.

BACKGROUND: Recent research has explored the use of higher risk extended criteria donors (ECDs) as a means of expanding the donor pool for heart transplantation. Here we sought to explore the current geographic distribution and survival outcomes of ECD utilization in various regions across the United States. METHODS: The United Network for Organ Sharing database was retrospectively queried for adult primary heart transplantation from 2000 to 2019. The EXPAND trial definition of ECD was used: ischemic time ≥ 4 hours, ejection fraction < 50%, age > 55 years, and history of coronary artery disease. Geographic data and 2019 population estimates were obtained from the US Census Bureau. RESULTS: Of the 42 642 transplants included in our analysis, 11 750 (27.6%) used ECDs. Region utilization of ECDs ranged from 18.4% to 46.5% of transplants. Region 6 had the highest utilization rate at 46.5%; this was primarily driven by the number of transplants with ischemic time ≥ 4 hours. Region 6 encompasses the largest total area (1.08 million square miles) and smallest population density (15.6 people per square mile). Region 8 had the lowest marginal donor utilization rate at 18.4%. Regions with high utilization of low ejection fractions, older donors, and donors with coronary artery disease (ie, regions 1 and 2) were able to maintain an average utilization rate of ECDs by maintaining short ischemic times. CONCLUSIONS: Large discrepancies in the use of ECDs exist across the different United Network for Organ Sharing regions. This is primarily driven by longer ischemic times, likely guided by variance in population densities between different regions.

Interaction between ischemic time and donor age under the new donor heart allocation system: Effect on post-transplant survival.

BACKGROUND: Ischemic time (IT) under the new heart transplant (HTx) allocation system has increased compared to the old system. We investigated the effect of IT and donor age on post-HTx survival. METHODS: The United Network for Organ Sharing (UNOS) database was analyzed to identify adult HTx between October 2015 and August 2020. Recipients were stratified by donor age, transplantation era, and IT. Kaplan-Meier and log-rank tests were used to compare 180-day post-HTx mortality. Cox proportional hazards modeling and propensity score matching were performed to adjust for confounders. RESULTS: Under the new system (N = 3654), IT≥4 h led to decreased survival compared to IT < 4 h (91.4% vs. 93.7%; P = .02), although this decrease was undetectable among those with donors ≥39 years old (90.4% vs. 91.1%; P = .73). IT≥4 h led to decreased survival with donors < 39 years old (91.7% vs. 94.6%; P < .01). Under the old system (N = 5987), IT≥4 h resulted in decreased survival (89.8% vs. 93.9%; P < .01), including with donors ≥39 years old (86.9% vs. 92.4%; P < .01). CONCLUSIONS: IT≥4 h remains a risk for post-HTx mortality under the new system. However, the magnitude of this effect is blunted when donor age is ≥39 years, likely secondary to increased allocation of these organs to lower status, more stable recipients.

Microaxial Left Ventricular Assist Device Versus Intraaortic Balloon Pump as a Bridge to Transplant.

BACKGROUND: Heart transplantation (HTx) candidates supported by Impella (Abiomed, Danvers, MA) or intraaortic balloon pump (IABP), who demonstrate evidence of cardiogenic shock, may qualify for waitlist status 2 without exception under the new donor heart allocation system. However limited data comparing Impella versus IABP as a bridge to HTx exist. METHODS: The United Network for Organ Sharing database was queried for adults listed and/or transplanted between January 2014 and February 2020. Temporal trends regarding Impella and IABP use were analyzed using the Royston trend test and χ2 test. Waitlist mortality was examined using Fine-Gray competing risks analysis. Post-HTx 180-day survival was analyzed using the Kaplan-Meier method and Cox proportional hazards models. RESULTS: Impella use increased from 0.2% in 2014 to 2.6% in 2020 (P < .01) and from 0.4% to 2.2% (P < .01) under the new allocation system. IABP use increased from 4.9% in 2014 to 27.6% in 2020 (P < .01) and from 6.7% to 26.6% (P < .01) under the new allocation system. Post-HTx survival was similar between groups (adjusted hazard ratio, 0.82; 95% CI, 0.38-1.78) despite more preoperative ventilation (3.6% vs 1.1%, P = .01) and higher model for end-stage liver disease excluding international normalized ratio scores (12.4 vs 9.5, P < .01) among Impella-supported recipients. Under the new system Impella-supported candidates were at higher risk of waitlist delisting compared with IABP-supported candidates (subhazard ratio, 2.42; 95% CI, 1.19-4.92). CONCLUSIONS: Post-HTx survival is comparable between Impella-supported and IABP-supported recipients despite worse preoperative profiles among Impella-supported recipients. Higher risk of waitlist delisting among Impella-supported candidates under the new allocation system requires close attention.

Durable Left Ventricular Assist Device as a Bridge to Heart Transplantation Under the New Donor Heart Allocation System.

The new donor heart allocation system prioritizes candidates supported by temporary devices. However, waitlist and posttransplant outcomes in candidates with durable left ventricular assist device (LVAD) remain to be elucidated. The United Network for Organ Sharing database was queried for adults listed from October 2015 to March 2020 for a single-organ, first-time heart transplant (HTx) with a durable LVAD. Waitlist removal within 1 year because of death or clinical deterioration and HTx was analyzed using competing risks regression. Candidates who underwent HTx within 1 year of listing were identified for examination of post-HTx survival using the Kaplan-Meier method and Cox proportional hazards models. Compared with candidates listed under the old system (n = 2,122), candidates listed under the new system (n = 1,562) were slightly younger ( p = 0.04) but had higher body mass index ( p < 0.01). Those listed under the new system were significantly less likely to experience waitlist removal because of death or clinical deterioration (subhazard ratio [HR] 0.68, 95% CI 0.52-0.90) but were also less likely to undergo HTx (sub-HR 0.91, 95% CI 0.83-0.998). Those who survived to HTx were more likely to experience death or need for re-HTx within 1 year of HTx under the new system (adjusted HR 1.50, 95% CI 1.11-2.03). Candidates with durable LVAD experience favorable waitlist outcomes under the new allocation system, although those who undergo HTx may be at increased mortality risk. Thus, candidates with a durable LVAD should be carefully selected for HTx listing under the new allocation system.

Prolonged waitlisting is associated with mortality in extracorporeal membrane oxygenation-supported heart transplantation candidates.

Objective: Heart transplantation (HTx) candidates supported with venoarterial extracorporeal membrane oxygenation (ECMO) may be listed at highest status 1 but are at inherent risk for ECMO-related complications. The effect of waitlist time on postlisting survival remains unclear in candidates with ECMO support who are listed using the new allocation system. Methods: Adult candidates listed with ECMO for a first-time, single-organ HTx from October 18, 2018, to March 21, 2021, in the Scientific Registry of Transplant Recipients database were included and stratified according to waitlist time (≤7 vs ≥8 days). Postlisting outcomes were compared between cohorts. Results: Among 175 candidates waitlisted for ≤7 days, 162 (92.6%) underwent HTx whereas 13 (7.4%) died/deteriorated compared with 41 (57.8%) and 21 (29.6%) of the 71 candidates waitlisted for ≥8 days, respectively (P < .01). Blood type O candidates (odds ratio [OR], 2.94; 95% CI, 1.54-5.61) were more likely to wait ≥8 days whereas candidates with concurrent intra-aortic balloon pump were less likely (OR, 0.30; 95% CI, 0.10-0.89). Obesity was additionally associated among those listed at status 1 (OR, 2.04; 95% CI, 1.00-4.17). Waitlisting for ≥8 days was independently associated with 90-day postlisting mortality conditional on survival to day 8 postlisting (hazard ratio, 5.59; 95% CI, 2.59-12.1). Candidates listed at status 1 showed similar trends (hazard ratio, 5.49; 95% CI, 2.39-12.6). There was no significant difference in 90-day post-HTx survival depending on whether a candidate waited for ≥8 days versus ≤7 days (92.7 vs 92.0%; log rank P = .87). Conclusions: Among ECMO-supported candidates, obtaining HTx within 1 week of listing might improve overall survival.

Continuous-Flow Left Ventricular Assist Device Support in Patients with Ischemic Versus Nonischemic Cardiomyopathy.

To determine whether the cause of cardiomyopathy affects outcomes in patients who undergo continuous-flow left ventricular assist device support, we compared postimplant adverse events and survival between patients with ischemic and nonischemic cardiomyopathy. The inclusion criteria for the ischemic group were a history of myocardial infarction or revascularization (coronary artery bypass grafting or percutaneous coronary intervention), ≥75% stenosis of the left main or proximal left anterior descending coronary artery, or ≥75% stenosis of ≥2 epicardial vessels. From November 2003 through March 2016, 526 patients underwent device support: 256 (48.7%) in the ischemic group and 270 (51.3%) in the nonischemic group. The ischemic group was older (60.0 vs 50.0 yr), included more men than women (84.0% vs 72.6%), and had more comorbidities. More patients in the nonischemic group were able to have their devices explanted after left ventricular recovery (5.9% vs 2.0%; P=0.02). More patients in the ischemic group had gastrointestinal bleeding (31.2% vs 22.6%; P=0.03), particularly from arteriovenous malformations (20.7% vs 11.9%; P=0.006) and ulcers (16.4% vs 9.3%; P=0.01). Kaplan-Meier analysis revealed no difference in overall survival between groups (P=0.24). Older age, previous sternotomy, higher total bilirubin level, and concomitant procedures during device implantation independently predicted death (P ≤0.03), whereas cause of heart failure did not (P=0.08). Despite the similarity in overall survival between groups, ischemic cardiomyopathy was associated with more frequent gastrointestinal bleeding. This information may help guide the care of patients with ischemic cardiomyopathy who receive continuous-flow left ventricular assist device support.

Bridging With Extracorporeal Membrane Oxygenation Under the New Heart Allocation System: A United Network for Organ Sharing Database Analysis.

BACKGROUND: The effect of the new donor heart allocation system on survival following bridging to transplantation with venous-arterial extracorporeal membrane oxygenation remains unknown. The new allocation system places extracorporeal membrane oxygenation-supported candidates at the highest status. METHODS: The United Network for Organ Sharing database was queried for adults bridged to single-organ heart transplantation with extracorporeal membrane oxygenation from October 2006 to February 2020. Association between implementation of the new system and recipient survival was analyzed using Kaplan-Meier estimates, Cox proportional hazards models, and propensity score matching. RESULTS: Of 364 recipients included, 173 and 191 were transplanted under new and old systems, respectively. Compared with the old system, waitlist time was halved under the new system (5 versus 10 days, P<0.01); recipients also demonstrated lower rates of prior cardiac surgery (32.9% versus 44.5%, P=0.03) and preoperative ventilation (30.6% versus 42.4%, P=0.02). Unadjusted 180-day survival was 90.2% (95% CI, 84.7%-94.2%) and 69.6% (95% CI, 62.6%-76.1%) under the new and old systems, respectively. Cox proportional hazards analysis demonstrated listing and transplantation under the new system to be an independent predictor of post-transplant survival (adjusted hazard ratio, 0.34 [95% CI 0.20-0.59]). Propensity score matching demonstrated a similar trend (hazard ratio, 0.36 [95% CI, 0.19-0.66]). Candidates listed under the new system were significantly less likely to experience waitlist mortality or deterioration (subhazard ratio, 0.38 [95% CI, 0.25-0.58]) and more likely to survive to transplant (subhazard ratio, 4.29 [95% CI, 3.32-5.54]). CONCLUSIONS: Recipients transplanted following extracorporeal membrane oxygenation bridging to transplantation under the new system achieve greater 180-day survival compared with the old and demonstrate less preoperative comorbidity. Waitlist outcomes have also improved significantly under the new allocation system.

Left thoracotomy vs full sternotomy for centrifugal durable LVAD implantation: 1-year outcome comparison post-LVAD and post-heart transplantation.

Left ventricular assist device (LVAD) implantations have traditionally been approached through a full median sternotomy (FS). Recently, a minimally invasive left thoracotomy (LT) approach has been popularized. This study sought to compare the outcomes of FS and LT patients post-primary LVAD implantation and post-subsequent heart transplant (HT). This was a single-center retrospective study. 83 patients who underwent primary centrifugal durable LVAD implantation from January 2014 to June 2018 were included (FS, n = 41; LT, n = 42). 41 patients had a subsequent HT (FS, n = 19; LT, n = 22). Pre-operative patient demographics, intraoperative variables, post-operative 1-year survival, length of hospital stay, complications, and outcomes for LVAD implantation and following HT were analyzed. Intraoperative data showed that the LT group had a 23.4% longer mean LVAD implant surgical time (p < 0.01). One-year post-LVAD survival was similar between the two groups (p = 0.05). Complication rates, with the exception of the rate of hemorrhagic stroke (p = 0.04) post-LVAD implant were similar. One-year survival post-HT was similar between groups (p = 0.35). Complication rates and mean length of hospital stay were also similar (p = 1.0) post-HT. Our study demonstrated that LT approach does not negatively affect post-LVAD implantation or post-HT outcomes. Further, larger studies may determine more detailed effects of LT approach.

Right ventricular undersizing is associated with increased 1-year mortality.

OBJECTIVES: Right heart hemodynamic management is critical, because many post-heart transplantation (HTx) complications are related to right ventricular (RV) failure. However, current guidelines on size and sex matching rely primarily on weight matching, with recent literature using total ventricular mass (TVM), which places less emphasis on the impact of RV mass (RVM) matching. The aim of the present study was to analyze the relationship of RVM matching and survival after HTx. METHODS: We performed the retrospective analysis using the UNOS database of adult HTx performed between January 1997 and December 2017. Previously validated equations were used to calculate TVM and RVM. The percent difference in ventricular mass in the donor and recipient pair was used for the size mismatch. All donor-recipient pairs were divided into 4 RVM groups by their mismatch ratio. We analyzed RVM matching and explored how RVM undersizing impacted outcomes. The primary outcome measure was 1-year survival; secondary outcomes measured included stroke and dialysis within 1 year and functional status. RESULTS: A total of 38,740 donor-recipient pairs were included in our study. The 4 RVM match groupings were as follows: <0%, 0% to 20%, 20% to 40%, and >40%. Utilization of donors who were older and of female sex resulted in greater RVM undersizing. Survival analysis demonstrated patients with RVM undersizing had worse 1-year survival (P < .001). RVM undersizing was an independent predictor of higher 1-year mortality (hazard ratio, 1.23; 95% confidence interval, 1.11 to 1.34; P < .001). RVM undersizing was also associated with higher rates of dialysis within 1-year of transplantation and poorer postoperative functional status. CONCLUSIONS: RVM undersizing is an independent predictor for worse 1-year survival. Donors who are older and female have lower absolute predicted RVM and may be predisposed to RVM undersizing. RVM-undersized transplantation requires careful risk/benefit considerations.

Continuous-Flow Left Ventricular Assist Device Therapy in Adults with Transposition of the Great Vessels.

An increasing number of children with congenital heart disease are surviving into adulthood and subsequently developing end-stage heart failure. Two example populations are adults who have been previously operated on for congenitally corrected transposition of the great arteries (CCTGA) and transposition of the great arteries (TGA). Implantation of a continuous flow left ventricular assist device (CF-LVAD) in these patients can present unusual anatomical and physiologic challenges. In this report, we describe outcomes of CF-LVAD implantation in three such patients. These cases demonstrate the feasibility of implanting a CF-LVAD in patients who have undergone surgery for CCTGA and/or TGA.

Left Ventricular Recovery with Explantation of Continuous-Flow Left Ventricular Assist Device after 5 Years of Support.

Mechanical circulatory support may result in sufficient myocardial recovery to allow for explantation of the left ventricular assist device (LVAD). The duration of support associated with left ventricular recovery has generally been 6-12 months. In this report, we present a patient in whom the left ventricle recovered after 5 years of support with a LVAD. Our report demonstrates that long-term monitoring for left ventricular recovery is prudent and may allow for late device explantation.

Sex, Racial, and Ethnic Disparities in U.S. Cardiovascular Trials in More Than 230,000 Patients.

BACKGROUND: The current representation of female patients and racial and ethnic minorities in cardiovascular trials is unclear. We evaluated these groups' inclusion in U.S. cardiovascular trials. METHODS: Using publicly available data from ClinicalTrials.gov, we evaluated cardiovascular trials pertaining to coronary artery bypass grafting (CABG), heart valve disease, aortic aneurysm, ventricular assist devices, and heart transplantation. This yielded 178 U.S. trials (159 completed, 19 active but not recruiting) started between September 1998 and May 2017, with 237,132 participants. To examine female patients' and racial and ethnic minorities' representation in these trials, we calculated participation-to-prevalence ratios (PPRs). Values of 0.8 to 1.2 reflect similar representation. RESULTS: All 178 trials reported sex distribution, whereas only 76 (42.7%) trials reported racial distribution and 52 (29.2%) trials reported ethnic (Hispanic vs non-Hispanic) distribution. Among all trials, participants were 28.3% female, 11.2% were Hispanic/Latino, 4.0% were African American, 10.4% were Asian, and 2.3% were other. The CABG PPR for female patients was 0.64, for Hispanic patients was 0.72, for African American patients was 0.28, and for Asian patients was 3.20. Between 2008-2012 and 2013-2017, the CABG PPR decreased for female patients (0.67→0.50) and African American patients (0.37→0.17) but increased for Hispanic patients (0.38→1.32) and Asian patients (3.51→4.57). CONCLUSIONS: Participation in cardiovascular trials by female patients and minorities (except Asian patients) remains low. Given that inherent differences among the previously mentioned groups could affect outcomes, balance is clearly needed. The engagement of our surgical leadership, community, and industry to address these disparities is vitally important.

Sternum-Sparing HVAD Implantation with Attachment of the Outflow Graft to the Descending Aorta.

The standard approach for implanting an HVAD left ventricular assist device (LVAD) is performing a median sternotomy and sewing the outflow graft to the ascending aorta. However, in patients with sternal comorbidities, it may be advantageous to use a sternum-sparing approach. We retrospectively studied eight patients who underwent HVAD implantation for destination therapy via a left subcostal or fifth/sixth intercostal space incision. With this procedure, the outflow graft was sewed to the descending aorta. Ninety-day and one-year survival rates were 87.5% and 75%, respectively. Two patients (25%) died during the perioperative period: one from multisystem organ failure and the other from unrelated causes. We adjusted the HVAD speed to open the aortic valve once every three to four beats. Compared with other continuous-flow LVAD implantations performed at our institution during the study period (n = 437), this technique resulted in shorter bypass times and a lower incidence of infection; it was not associated with an increased incidence of heart failure, aortic root thrombosis, pump thrombosis, progression of aortic insufficiency, or ischemic neurologic dysfunction. Our findings suggest that a sternum-sparing approach for HVAD implantation is feasible and may be a safe option in patients with serious comorbidities that preclude the use of traditional implantation techniques.

Effect of cardiac arrest with aortic cross-clamping during left ventricular assist device implantation.

OBJECTIVES: Some patients who undergo continuous-flow left ventricular assist device (CF-LVAD) implantation require concomitant procedures that can be performed with or without cardiac arrest under aortic cross-clamping (AXC). Procedures normally performed with cardiac arrest are sometimes avoided or performed without cardiac arrest because it may be detrimental to right heart function. However, the effects of cardiac arrest on patients with advanced heart failure necessitating CF-LVAD support have not been thoroughly studied. We examined our single-centre experience to determine whether cardiac arrest during CF-LVAD implantation was associated with worse patient outcomes. METHODS: From November 2003 to March 2016, a total of 526 patients with chronic end-stage heart failure underwent primary CF-LVAD implantation. Preoperative demographics, postoperative complications and mortality rates were compared between patients who required cardiac arrest with AXC (n = 50) and those who did not (n = 476). RESULTS: The most frequently performed procedure requiring AXC was aortic valve closure (n = 23, 26.1%). Although the AXC group had longer cardiopulmonary bypass times (P < 0.01), long-term (5-year) survival was similar in AXC and non-AXC patients (P = 0.13). Also, postoperative right heart failure (P = 0.15) and neurological dysfunction (P = 0.89) rates were not significantly different between the 2 groups. Cox proportional hazards analysis showed that cardiac arrest with AXC was not an independent predictor of mortality (hazard ratio, 0.89; P = 0.73). CONCLUSIONS: Cardiac arrest with AXC during CF-LVAD implantation did not negatively affect long-term survival or the incidence of right ventricular failure or stroke. These findings should be considered in deciding surgical strategies. Additional investigation may be warranted to further understand the effects of cardiac arrest during LVAD implantation.