Intimal hyperplasia, saphenous vein graft disease, and clinical outcomes: Insights from the CTSN VEST randomized trial

BACKGROUND

Diffuse intimal hyperplasia and graft irregularity adversely affect the long-term patency of saphenous vein grafts (SVGs) and clinical outcomes of patients undergoing coronary artery bypass grafting (CABG). The VEST trial evaluated the efficacy of external graft support in limiting the development of intimal hyperplasia (IH) at 1 year postsurgery. In the present secondary analysis, we explored the associations between graft disease and IH and clinical events. We also examined risk factors for early graft occlusion.

METHODS

VEST is a within-patient randomized, multicenter trial that enrolled 224 patients with multivessel coronary disease undergoing CABG surgery, of whom 203 were evaluated by 1 year postsurgery. Intimal hyperplasia, lumen uniformity, graft stenosis, and graft perfusion were measured by intravascular ultrasound and angiography. Major cardiac and cerebrovascular events (MACCE; including death, myocardial infarction, stroke, and revascularization) were recorded over a median follow-up of 3 years.

RESULTS

Worse lumen uniformity, greater stenosis, and worse graft perfusion were associated with higher IH values and an increased incidence of clinical events. Consistent with previous findings, we identified endoscopic vein harvesting, female sex, and transit time flow measurement of pulsatility index and flow as risk factors for SVG occlusion during the first year postsurgery.

CONCLUSIONS

In this secondary analysis of the VEST trial, we observed an association between intimal hyperplasia area and clinical measures of SVG disease at 1 year postsurgery. More severe SVG disease and larger areas of IH were associated with a higher incidence of 3-year MACCE. Ongoing follow-up to 5 years will further elucidate the impact of SVG disease on long-term clinical outcomes of CABG.

A multicenter evaluation of external outflow graft obstruction with a fully magnetically levitated left ventricular assist device

BACKGROUND

The HeartMate 3 (HM 3; Abbott) left ventricular assist device (LVAD) has improved hemocompatibility-related adverse outcomes. In sporadic cases, external compression of the outflow graft causing obstruction (eOGO) can result from substance accumulation between the outflow graft and its bend relief. We sought to evaluate the prevalence, course, and clinical implications of eOGO in an international study.

METHODS

A multicenter retrospective analysis of HM 3 LVADs implanted between November 2014 and April 2021 (n = 2108) was conducted across 17 cardiac centers in 8 countries. We defined eOGO as obstruction >25% in the cross-sectional area in imaging (percutaneous angiography, computed tomography, or intravascular ultrasound). The prevalence and annual incidence were calculated. Serious adverse events and outcomes (death, transplantation, or device exchange) were analyzed for eOGO cases.

RESULTS

Of 2108 patients, 62 were diagnosed with eOGO at a median LVAD support duration of 953 (interquartile range, 600-1267) days. The prevalence of eOGO was 3.0% and the incidence at 1, 2, 3, 4, and 5 years of support was 0.6%, 2.8%, 4.0%, 5.2%, and 9.1%, respectively. Of 62 patients, 9 were observed, 27 underwent surgical revision, 15 underwent percutaneous stent implantation, 8 received a heart transplant, and 2 died before intervention. One patient underwent surgical revision and later stent implantation. The mortality with therapeutic intervention was 9/53 (17.0%).

CONCLUSIONS

Although uncommon, HM 3 LVAD-supported patients might develop eOGO with an increasing incidence after 1 year of support. Although engineering efforts to reduce this complication are under way, clinicians must maintain a focus on early detection and remain vigilant.

Use of Extracorporeal Membrane Oxygenation for Primary Graft Dysfunction After Cardiac Transplantation: Results of an A Priori Ventless Approach

Primary graft dysfunction (PGD) after cardiac transplantation is a devastating complication with increasing frequency lately in the setting of donation after circulatory death (DCD). Severe PGD is commonly treated with extracorporeal membrane oxygenation (ECMO) using central or peripheral cannulation. We retrospectively reviewed the outcomes of PGD after cardiac transplantation requiring ECMO support at our center from 2015 to 2020, focused on our now preferential approach using peripheral cannulation without a priori venting. During the study period, 255 patients underwent heart transplantation at our center and 26 (10.2%) of them required ECMO for PGD. Of 24 patients cannulated peripherally 19 (79%) were alive at 30 days and 17 (71%) 1 year after transplant; two additional patients underwent central ECMO cannulation due to unfavorable size of femoral vessels and concern for limb ischemia. Successful decannulation with full graft function recovery occurred in 22 of 24 (92%) patients cannulated peripherally. Six of them had an indwelling intra-aortic balloon pump placed before the transplantation. None of the other 18 patients received a ventricular vent. In conclusion, the use of an a priori peripheral and ventless ECMO approach in patients with PGD after heart transplant is an effective strategy associated with high rates of graft recovery and survival.

Aspirin and Hemocompatibility Events With a Left Ventricular Assist Device in Advanced Heart Failure: The ARIES-HM3 Randomized Clinical Trial

IMPORTANCE

Left ventricular assist devices (LVADs) enhance quality and duration of life in advanced heart failure. The burden of nonsurgical bleeding events is a leading morbidity. Aspirin as an antiplatelet agent is mandated along with vitamin K antagonists (VKAs) with continuous-flow LVADs without conclusive evidence of efficacy and safety.

OBJECTIVE

To determine whether excluding aspirin as part of the antithrombotic regimen with a fully magnetically levitated LVAD is safe and decreases bleeding.

DESIGN, SETTING, and PARTICIPANTS

This international, randomized, double-blind, placebo-controlled study of aspirin (100 mg/d) vs placebo with VKA therapy in patients with advanced heart failure with an LVAD was conducted across 51 centers with expertise in treating patients with advanced heart failure across 9 countries. The randomized population included 628 patients with advanced heart failure implanted with a fully magnetically levitated LVAD (314 in the placebo group and 314 in the aspirin group), of whom 296 patients in the placebo group and 293 in the aspirin group were in the primary analysis population, which informed the primary end point analysis. The study enrolled patients from July 2020 to September 2022; median follow-up was 14 months.

Intervention

Patients were randomized in a 1:1 ratio to receive aspirin (100 mg/d) or placebo in addition to an antithrombotic regimen.

MAIN OUTCOMES AND MEASURES

The composite primary end point, assessed for noninferiority (-10% margin) of placebo, was survival free of a major nonsurgical (>14 days after implant) hemocompatibility-related adverse events (including stroke, pump thrombosis, major bleeding, or arterial peripheral thromboembolism) at 12 months. The principal secondary end point was nonsurgical bleeding events.

RESULTS

Of the 589 analyzed patients, 77% were men; one-third were Black and 61% were White. More patients were alive and free of hemocompatibility events at 12 months in the placebo group (74%) vs those taking aspirin (68%). Noninferiority of placebo was demonstrated (absolute between-group difference, 6.0% improvement in event-free survival with placebo [lower 1-sided 97.5% CI, -1.6%]; P < .001). Aspirin avoidance was associated with reduced nonsurgical bleeding events (relative risk, 0.66 [95% confidence limit, 0.51-0.85]; P = .002) with no increase in stroke or other thromboembolic events, a finding consistent among diverse subgroups of patient characteristics.

CONCLUSIONS AND RELEVANCE

In patients with advanced heart failure treated with a fully magnetically levitated LVAD, avoidance of aspirin as part of an antithrombotic regimen, which includes VKA, is not inferior to a regimen containing aspirin, does not increase thromboembolism risk, and is associated with a reduction in bleeding events.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT04069156.

Predictors of 5-Year Mortality in Patients Managed With a Magnetically Levitated Left Ventricular Assist Device

BACKGROUND

In advanced heart failure patients implanted with a fully magnetically levitated HeartMate 3 (HM3, Abbott) left ventricular assist device (LVAD), it is unknown how preimplant factors and postimplant index hospitalization events influence 5-year mortality in those able to be discharged.

OBJECTIVES

The goal was to identify risk predictors of mortality through 5 years among HM3 LVAD recipients conditional on discharge from index hospitalization in the MOMENTUM 3 pivotal trial.

METHODS

This analysis evaluated 485 of 515 (94%) patients discharged after implantation of the HM3 LVAD. Preimplant (baseline), implant surgery, and index hospitalization characteristics were analyzed individually, and as multivariable predictors for mortality risk through 5 years.

RESULTS

Cumulative 5-year mortality in the cohort (median age: 62 years, 80% male, 65% White, 61% destination therapy due to transplant ineligibility) was 38%. Two preimplant characteristics (elevated blood urea nitrogen and prior coronary artery bypass graft or valve procedure) and 3 postimplant characteristics (hemocompatibility-related adverse events, ventricular arrhythmias, and estimated glomerular filtration rate <60 mL/min/1.73 m2 at discharge) were predictors of 5-year mortality. In 171 of 485 patients (35.3%) without any risk predictors, 5-year mortality was reduced to 22.6% (95% CI: 15.4%-32.7%). Even among those with 1 or more predictors, mortality was <50% at 5 years (45.7% [95% CI: 39.0%-52.8%]).

CONCLUSIONS

Long-term survival in successfully discharged HM3 LVAD recipients is largely influenced by clinical events experienced during the index surgical hospitalization in tandem with baseline factors, with mortality of <50% at 5 years. In patients without identified predictors of risk, long-term 5-year mortality is low and rivals that achieved with heart transplantation, even though most were implanted with destination therapy intent. (MOMENTUM 3 IDE Clinical Study Protocol, NCT02224755; MOMENTUM 3 Pivotal Cohort Extended Follow-up PAS, NCT03982979).

Early Outcomes of Adult Heart Transplantation From COVID-19 Infected Donors

BACKGROUND

There is a paucity of data on heart transplantation (HT) using COVID-19 donors.

OBJECTIVES

This study investigated COVID-19 donor use, donor and recipient characteristics, and early post-HT outcomes.

METHODS

Between May 2020 and June 2022, study investigators identified 27,862 donors in the United Network for Organ Sharing, with 60,699 COVID-19 nucleic acid amplification testing (NAT) performed before procurement and with available organ disposition. Donors were considered "COVID-19 donors" if they were NAT positive at any time during terminal hospitalization. These donors were subclassified as "active COVID-19" (aCOV) donors if they were NAT positive within 2 days of organ procurement, or "recently resolved COVID-19" (rrCOV) donors if they were NAT positive initially but became NAT negative before procurement. Donors with NAT-positive status >2 days before procurement were considered aCOV unless there was evidence of a subsequent NAT-negative result ≥48 hours after the last NAT-positive result. HT outcomes were compared.

RESULTS

During the study period, 1,445 "COVID-19 donors" (COVID-19 NAT positive) were identified; 1,017 of these were aCOV, and 428 were rrCOV. Overall, 309 HTs used COVID-19 donors, and 239 adult HTs from COVID-19 donors (150 aCOV, 89 rrCOV) met study criteria. Compared with non-COV, COVID-19 donors used for adult HT were younger and mostly male (∼80%). Compared with HTs from non-COV donors, recipients of HTs from aCOV donors had increased mortality at 6 months (Cox HR: 1.74; 95% CI: 1.02-2.96; P = 0.043) and 1 year (Cox HR: 1.98; 95% CI: 1.22-3.22; P = 0.006). Recipients of HTs from rrCOV and non-COV donors had similar 6-month and 1-year mortality. Results were similar in propensity-matched cohorts.

CONCLUSIONS

In this early analysis, although HTs from aCOV donors had increased mortality at 6 months and 1 year, HTs from rrCOV donors had survival similar to that seen in recipients of HTs from non-COV donors. Continued evaluation and a more nuanced approach to this donor pool are needed.

Transplantation Outcomes with Donor Hearts after Circulatory Death

BACKGROUND

Data showing the efficacy and safety of the transplantation of hearts obtained from donors after circulatory death as compared with hearts obtained from donors after brain death are limited.

METHODS

We conducted a randomized, noninferiority trial in which adult candidates for heart transplantation were assigned in a 3:1 ratio to receive a heart after the circulatory death of the donor or a heart from a donor after brain death if that heart was available first (circulatory-death group) or to receive only a heart that had been preserved with the use of traditional cold storage after the brain death of the donor (brain-death group). The primary end point was the risk-adjusted survival at 6 months in the as-treated circulatory-death group as compared with the brain-death group. The primary safety end point was serious adverse events associated with the heart graft at 30 days after transplantation.

RESULTS

A total of 180 patients underwent transplantation; 90 (assigned to the circulatory-death group) received a heart donated after circulatory death and 90 (regardless of group assignment) received a heart donated after brain death. A total of 166 transplant recipients were included in the as-treated primary analysis (80 who received a heart from a circulatory-death donor and 86 who received a heart from a brain-death donor). The risk-adjusted 6-month survival in the as-treated population was 94% (95% confidence interval [CI], 88 to 99) among recipients of a heart from a circulatory-death donor, as compared with 90% (95% CI, 84 to 97) among recipients of a heart from a brain-death donor (least-squares mean difference, -3 percentage points; 90% CI, -10 to 3; P<0.001 for noninferiority [margin, 20 percentage points]). There were no substantial between-group differences in the mean per-patient number of serious adverse events associated with the heart graft at 30 days after transplantation.

CONCLUSIONS

In this trial, risk-adjusted survival at 6 months after transplantation with a donor heart that had been reanimated and assessed with the use of extracorporeal nonischemic perfusion after circulatory death was not inferior to that after standard-care transplantation with a donor heart that had been preserved with the use of cold storage after brain death. (Funded by TransMedics; ClinicalTrials.gov number, NCT03831048.).

Cystic Tumor of the Atrioventricular Node Causing Rapid-Onset and Reversible Complete Heart Block

Cystic tumors of the atrioventricular node are rare primary cardiac neoplasms, frequently reported as a postmortem diagnosis during autopsy. Despite their small size, they can present with complete heart block or sudden cardiac death. Herein, we present a case of rapidly progressing high-grade atrioventricular block that improved after surgery. (Level of Difficulty: Intermediate.).

Five-Year Outcomes in Patients With Fully Magnetically Levitated vs Axial-Flow Left Ventricular Assist Devices in the MOMENTUM 3 Randomized Trial

IMPORTANCE

Although durable left ventricular assist device (LVAD) therapy has emerged as an important treatment option for patients with advanced heart failure refractory to pharmacological support, outcomes, including survival, beyond 2 years remain poorly characterized.

OBJECTIVE

To report the composite end point of survival to transplant, recovery, or LVAD support free of debilitating stroke (Modified Rankin Scale score >3) or reoperation to replace the pump 5 years after the implant in participants who received the fully magnetically levitated centrifugal-flow HeartMate 3 or axial-flow HeartMate II LVAD in the MOMENTUM 3 randomized trial and were still receiving LVAD therapy at the 2-year follow-up.

DESIGN, SETTING, AND PARTICIPANTS

This observational study was a 5-year follow-up of the MOMENTUM 3 trial, conducted in 69 US centers, that demonstrated superiority of the centrifugal-flow LVAD to the axial-flow pump with respect to survival to transplant, recovery, or LVAD support free of debilitating stroke or reoperation to replace the pump at 2 years. A total of 295 patients were enrolled between June 2019 to April 2021 in the extended-phase study, with 5-year follow-up completed in September 2021.

EXPOSURES

Of 1020 patients in the investigational device exemption per-protocol population, 536 were still receiving LVAD support at 2 years, of whom 289 received the centrifugal-flow pump and 247 received the axial-flow pump.

MAIN OUTCOMES AND MEASURES

There were 10 end points evaluated at 5 years in the per-protocol population, including a composite of survival to transplant, recovery, or LVAD support free of debilitating stroke or reoperation to replace the pump between the centrifugal-flow and axial-flow pump groups and overall survival between the 2 groups.

RESULTS

A total of 477 patients (295 enrolled and 182 provided limited data) of 536 patients still receiving LVAD support at 2 years contributed to the extended-phase analysis (median age, 62 y; 86 [18%] women). The 5-year Kaplan-Meier estimate of survival to transplant, recovery, or LVAD support free of debilitating stroke or reoperation to replace the pump in the centrifugal-flow vs axial-flow group was 54.0% vs 29.7% (hazard ratio, 0.55 [95% CI, 0.45-0.67]; P < .001). Overall Kaplan-Meier survival was 58.4% in the centrifugal-flow group vs 43.7% in the axial-flow group (hazard ratio, 0.72 [95% CI, 0.58-0.89]; P = .003). Serious adverse events of stroke, bleeding, and pump thrombosis were less frequent in the centrifugal-flow pump group.

CONCLUSIONS AND RELEVANCE

In this observational follow-up study of patients from the MOMENTUM 3 randomized trial, per-protocol analyses found that receipt of a fully magnetically levitated centrifugal-flow LVAD vs axial-flow LVAD was associated with a better composite outcome and higher likelihood of overall survival at 5 years. These findings support the use of the fully magnetically levitated LVAD.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT02224755 and NCT03982979.

External Support for Saphenous Vein Grafts in Coronary Artery Bypass Surgery: A Randomized Clinical Trial

Importance

Intimal hyperplasia and subsequent saphenous vein graft failure may have significant adverse clinical effects in patients undergoing coronary artery bypass surgery. External support of saphenous vein grafts has the potential to prevent vein graft dilation and hence slow the rate of intimal hyperplasia and increase long-term vein patency.

Objective

To determine efficacy, as measured by intimal hyperplasia, and safety of an external saphenous vein graft support device in patients undergoing a coronary bypass graft procedure.

Design, Setting, and Participants

This within-patient randomized, open-label, multicenter study was conducted at 17 Cardiothoracic Surgical Trials Network centers in North America. Between January 2018 and February 2019, 224 patients with multivessel coronary artery disease undergoing isolated bypass surgery were enrolled. For each patient, 1 of 2 vein grafts was randomized to receive external support or no support.

Interventions

External vein graft support or no support.

Main Outcomes and Measures

The primary efficacy end point was intimal hyperplasia area assessed by intravascular ultrasound at 12 months postrandomization for each study graft. Secondary confirmatory end points were lumen diameter uniformity assessed by angiography and graft failure (≥50% stenosis) by quantitative coronary angiography. Major cardiac and cerebrovascular events were collected through month 12.

Results

Among 224 patients (mean [SD] age, 65.8 [8.3] years; 178 [79.5%] male), 203 (90.6%) were eligible for intravascular ultrasound, of which 85 (41.9%) had at least 1 study graft occluded or severely diseased at 12 months (55 supported, 56 unsupported). After imputation of data missing because of graft occlusion or severe disease, the estimated mean (SE) intimal hyperplasia area was 5.11 (0.16) mm2 in supported grafts and 5.79 (0.20) mm2 in unsupported grafts (P = .07). In a sensitivity analysis of 113 patients with both grafts imaged, the mean intimal hyperplasia area was 4.58 (0.18) mm2 and 5.12 (0.23) mm2 in supported and unsupported grafts, respectively (P = .04). By 12 months, 5 patients (2.2%) died and 16 patients (7.1%) experienced a major cardiac or cerebrovascular event.

Conclusions and Relevance

The 12-month difference in intimal hyperplasia area between supported and unsupported grafts did not achieve statistical significance. Cumulative mortality and major cardiac or cerebrovascular events rates were similar to those in other randomized coronary artery bypass trials. Further investigation to assess the effect of external graft support devices on long-term graft patency and clinical outcomes is warranted.

Trial Registration

ClinicalTrials.gov Identifier: NCT03209609.

Hospitalization Patterns and Impact of a Magnetically-Levitated Left Ventricular Assist Device in the MOMENTUM 3 Trial

BACKGROUND

In the MOMENTUM 3 (Multicenter Study of MagLev Technology in Patients Undergoing Mechanical Circulatory Support Therapy with HeartMate 3) pivotal trial, the HeartMate 3 (HM3) fully magnetically levitated left ventricular assist device (LVAD) demonstrated superiority over the axial-flow HeartMate II (HMII) LVAD. The patterns and predictors of hospitalizations with the HM3 LVAD have not been characterized.

OBJECTIVES

This study sought to determine causes, predictors, and impact of hospitalizations during LVAD support.

METHODS

Patients discharged after LVAD implantation were analyzed. In the pivotal trial, 485 recipients of HM3 were compared with 471 recipients of HMII. The pivotal trial HM3 group was also compared to 949 recipients of HM3 in the postapproval phase within the trial portfolio. Predictors of cause-specific rehospitalization were analyzed.

RESULTS

The rates of rehospitalization were lower with HM3 LVAD than with HMII LVAD in the pivotal trial (225.7 vs 246.4 events per 100 patient-years; P < 0.05). Overall, rehospitalization rates and duration were similar in the HM3 postapproval phase and pivotal trial but prolonged hospitalizations (>7 days) were less frequent (rate ratio: 0.90 [95% CI: 0.80-0.98]; P < 0.05). In HM3 recipients, the most frequent causes of rehospitalization included infection, heart failure (HF)-related events, and bleeding. First rehospitalization caused by HF-related event versus other causes was associated with reduced survival (HR: 2.2 [95% CI: 1.3-3.9]; P = 0.0014). Male sex, non-White race, presence of cardiac resynchronization therapy/implantable cardioverter-defibrillator, obesity, higher right atrial pressure, smaller LV size, longer duration of index hospitalization, and lower estimated glomerular filtration rate at index discharge predicted HF hospitalizations.

CONCLUSIONS

Contemporary support with the HM3 fully magnetically levitated LVAD is associated with a lower hospitalization burden than with prior pumps; however, rehospitalizations for infection, HF, and bleeding remain important challenges for progress in the patient journey. (MOMENTUM 3 IDE Clinical Study, NCT02224755; MOMENTUM 3 Continued Access Protocol [MOMENTUM 3 CAP], NCT02892955).

Characteristics and outcomes of patients with COVID-19 supported by extracorporeal membrane oxygenation: A retrospective multicenter study

OBJECTIVE

To determine characteristics, outcomes, and clinical factors associated with death in patients with COVID-19 requiring extracorporeal membrane oxygenation (ECMO) support.

METHODS

A multicenter, retrospective cohort study was conducted. The cohort consisted of adult patients (18 years of age and older) requiring ECMO in the period from March 1, 2020, to September 30, 2020. The primary outcome was in-hospital mortality after ECMO initiation assessed with a time to event analysis at 90 days. Multivariable Cox proportional regression was used to determine factors associated with in-hospital mortality.

RESULTS

Overall, 292 patients from 17 centers comprised the study cohort. Patients were 49 (interquartile range, 39-57) years old and 81 (28%) were female. At the end of the follow-up period, 19 (6%) patients were still receiving ECMO, 25 (9%) were discontinued from ECMO but remained hospitalized, 135 (46%) were discharged or transferred alive, and 113 (39%) died during the hospitalization. The cumulative in-hospital mortality at 90 days was 42% (95% confidence interval [CI], 36%-47%). Factors associated with in-hospital mortality were age (adjusted hazard ratio [aHR], 1.31; 95% CI, 1.06-1.61 per 10 years), renal dysfunction measured according to serum creatinine level (aHR, 1.21; 95% CI, 1.01-1.45), and cardiopulmonary resuscitation before ECMO placement (aHR, 1.87; 95% CI, 1.01-3.46).

CONCLUSIONS

In patients with severe COVID-19 necessitating ECMO support, in-hospital mortality occurred in fewer than half of the cases. ECMO might serve as a viable modality for terminally ill patients with refractory COVID-19.

Center Variability in Patient Outcomes Following HeartMate 3 Implantation: An Analysis of the MOMENTUM 3 Trial

BACKGROUND

As left ventricular assist device (LVAD) survival rates continue to improve, evaluating site-specific variability in outcomes can facilitate identifying targets for quality-improvement initiative opportunities in the field.

METHODS

Deidentified center-specific outcomes were analyzed for HeartMate 3 (HM3) patients enrolled in the MOMENTUM 3 pivotal and continued access protocol trials. Centers < 25th percentile for HM3 volumes were excluded. Variability in risk-adjusted center mortality was assessed at 90 days and 2 years (conditional upon 90-day survival). Adverse event (AE) rates were compared across centers.

RESULTS

In the 48 included centers (1958 patients), study-implant volumes ranged between 17 and 106 HM3s. Despite similar trial-inclusion criteria, patient demographics varied across sites, including age quartile ((Q)1-Q3:57-62 years), sex (73%-85% male), destination therapy intent (60%-84%), and INTERMACS profile 1-2 (16%-48%). Center mortality was highly variable, nadiring at ≤ 3.6% (≤ 25th percentile) and peaking at ≥ 10.4% (≥ 75th percentile) at 90 days and ≤ 10.2% and ≥ 18.7%, respectively, at 2 years. Centers with low mortality rates tended to have lower 2-year AE rates, but no center was a top performer for all AEs studied.

CONCLUSIONS

Mortality and AEs were highly variable across MOMENTUM 3 centers. Studies are needed to improve our understanding of the drivers of outcome variability and to ascertain best practices associated with high-performing centers across the continuum of intraoperative to chronic stages of LVAD support.

Twelfth Interagency Registry for Mechanically Assisted Circulatory Support Report: Readmissions After Left Ventricular Assist Device

The twelfth annual report from The Society of Thoracic Surgeons (STS) Interagency Registry for Mechanically Assisted Circulatory Support (Intermacs) highlights outcomes for 26 688 continuous-flow left ventricular assist device (LVAD) patients over the past decade (2011-2020). In 2020, we observed the largest drop in yearly LVAD implant volumes since the registry's inception, which reflects the effects of the COVID-19 pandemic on cardiac surgical volumes in the United States. The 2018 heart transplant allocation policy change in the United States continues to affect LVAD implantation volumes and device strategy, with 78.1% of patients now receiving LVAD implants as destination therapy. Despite an older and sicker patient cohort, survival in the recent era (2016-2020) at 1 and 2 years continues to improve at 82.8% and 74.1%. Patient adverse event profile has also improved in the recent era, with significant reductions in stroke, gastrointestinal bleeding, infection, and device malfunction/pump thrombosis. Finally, we review the burden of readmissions after LVAD implant and highlight an opportunity to improve patient outcomes by reducing this frequent and vexing problem.

Characteristics and Outcomes of COVID-19 Patients Supported by Venoarterial or Veno-Arterial-Venous Extracorporeal Membrane Oxygenation

Objectives

Cardiac injury has been reported in up to 20%-to-30% of patients with COVID-19, and severe disease can lead to cardiopulmonary failure. The role of mechanical circulatory support in these patients remains undetermined. The authors here aimed to determine the characteristics and outcomes of patients with COVID-19 requiring venoarterial extracorporeal membrane oxygenation (VA ECMO) or veno-arterial-venous (VAV) ECMO support.

Design and Setting

A multicenter, retrospective case series.

Participants

The cohort consisted of adult patients (18 years of age and older) with confirmed COVID-19 requiring VA ECMO or VAV ECMO support in the period from March 1, 2020, to April 30, 2021. Outcomes were recorded until July 31, 2021.

Measurements and Main Results

To show factors related to death during hospitalization, patients were grouped as survivors and nonsurvivors. Kaplan-Meier analysis was used to estimate 90-day in-hospital mortality. Overall, 37 patients from 12 centers comprised the study cohort. The median patient age was 44 years old (interquartile range [IQR], 35-52), and 12 (32%) were female patients. The duration of ECMO support ranged from 2-to-132 days. At the end of the follow-up period, 13 patients (35%) were discharged or transferred alive, and 24 patients (65%) died during the hospitalization. The cumulative in-hospital mortality at 90 days was 64% (95% confidence interval: 47-81). During the time from intubation to VA ECMO or VAV ECMO initiation (1 day [IQR 0-7.5] v 6 days [IQR 2.5-14], p = 0.0383), body mass index (32 [IQR 26-36] v 37 [IQR 33-40], p = 0.009), and baseline C-reactive protein (7.15 v 38.9 mg/dL, p = 0.009) were higher in those who expired.

Conclusion

Only one-third of the patients with COVID-19 requiring VA ECMO or VAV ECMO survived to discharge. Close monitoring of at-risk patients with early initiation of ECMO with circulatory support may further improve outcomes.

Feasibility and Potential Impact of Heart Transplantation From Adult Donors After Circulatory Death

BACKGROUND

A shortage of donation after brain death (DBD) donors for heart transplantation (HT) persists. Recent improvements in organ procurement from donation after circulatory death (DCD) donors and promising early results of DCD-HTs from Europe and Australia have renewed interest in DCD-HT.

OBJECTIVES

The current study evaluated donor and recipient characteristics, early outcomes, and potential impact of adult DCD-HT in the United States.

METHODS

The United Network for Organ Sharing registry was used to identify and compare adult DCD donors based on their use for HT between January 2020 and February 2021. Adult DCD-HTs with available post-HT outcomes data were compared with contemporary adult DBD-HTs during study period using Cox-regression analysis and propensity-matching.

RESULTS

Of the 3,611 adult DCD donors referred during the study period, 136 were used for HT. DCD donors used for HT were younger (median age 29 years), and most were male (90%), and blood type O (79%). On comparing DCD-HT (n = 127) and DBD-HT (n = 2,961) meeting study criteria and with available data on post-HT outcomes, there was no significant difference in 30-day or 6-month mortality, primary graft failure up to 30 days, or other outcomes including in-hospital stroke, pacemaker insertion, hemodialysis, and post-HT length of hospital stay. Results were similar in propensity matched DCD-HT and DBD-HT cohorts. The number of potential adult DCD donors referred has increased substantially (n = 871 in 2010 to n = 3,045 in 2020), and the authors estimated that widespread adoption of DCD-HT could lead to approximately 300 additional adult HTs in the United States annually.

CONCLUSIONS

This preliminary analysis of adult DCD-HTs from the United States showed favorable early outcomes and suggested a potential for substantial increase in adult HT volumes with use of DCD donors.

Gastrointestinal angiodysplasia in heart failure and during CF LVAD support

Angiodysplasias (AGD) are common sites of bleeding in the gastrointestinal (GI) tract after Continuous Flow Left Ventricular Assist Device (CF-LVAD) implantation. We sought to investigate whether AGDs are formed as a result of LVAD physiology or preexist as a consequence of heart failure. Thirty-six subjects with HF reduced EF (HFrEF) underwent video capsule endoscopy (VCE) to assess for the presence of AGD. Fifty-three subjects without HF who underwent VCE for a nonbleeding indication formed a control group. The prevalence of AGD was significantly higher in the HFrEF compared to the non-HF controls (50% vs 13%, p = 0.0002). This association persisted after controlling for age and comorbidities. Within the HFrEF cohort, higher Ang2, NT-proBNP and BUN were associated with the presence of AGD. AGD in the GI tract are associated with HFrEF. This is the first description of a new pathology associated with HFrEF and adds to our understanding of CF LVAD associated GI bleeding.

Impact of Race on Clinical Outcomes After Implantation With a Fully Magnetically Levitated Left Ventricular Assist Device: An Analysis From the MOMENTUM 3 Trial

BACKGROUND

Heart failure disproportionately affects Black patients. Whether differences among race influence outcomes in advanced heart failure with use of a fully magnetically levitated continuous-flow left ventricular assist device remains uncertain.

METHODS

We included 515 IDE (Investigational Device Exemption) clinical trial patients and 500 Continued Access Protocol patients implanted with the HeartMate 3 left ventricular assist device in the MOMENTUM 3 study (Multicenter Study of MagLev Technology in Patients Undergoing Mechanical Circulatory Support Therapy With HeartMate 3). Outcomes were compared between Black and White left ventricular assist device recipients for the primary end point of survival free of disabling stroke or reoperation to replace or remove a malfunctioning device at 2 years, overall survival, adverse events, 6-minute walk distance, and quality of life scores.

RESULTS

Of 1015 HeartMate 3 patients, 675 were self-identified as White and 285 as Black individuals. The Black patient cohort was younger, more obese and with a history of hypertension, and more nonischemic cause of heart failure, relative to the White patient group. Black and White patients did not experience a difference in the primary end point (81.1% versus 77.9%; hazard ratio, 1.08 [95% CI, 0.76-1.54], P=0.6568). Black patients were at higher risk of adverse events (calculated as events per 100 patient-years), including bleeding (75.4 versus 63.5; P<0.0001), stroke (9.5 versus 7.2; P=0.0183), and hypertension (10.1 versus 3.2; P<0.0001). The 6-minute walk distance was not different at baseline and 6 months between the groups, however, the absolute change from baseline was greater for White patients (median: +183.0 [interquartile range, 42.0-335.3] versus +163.8 [interquartile range, 42.3-315.0] meters, P=0.01). The absolute quality of life measurement (EuroQoL group, 5-dimension, 5-level instrument visual analog scale) at baseline and 6 months was better in the Black patient group, but relative improvement from baseline to 6 months was greater in White patients (median: +20.0 [interquartile range, 5.0-40.0] versus +25.0 [interquartile range, 10.0-45.0]; P=0.0298).

CONCLUSIONS

Although the survival free of disabling stroke or reoperation to replace/remove a malfunctioning device at 2 years with the HM 3 left ventricular assist device did not differ by race, Black HeartMate 3 patients experienced a higher morbidity burden and smaller gains in functional capacity and quality of life when compared with White patients. These findings require efforts designed to better understand and overcome these gaps through systematic identification and tackling of putative factors. Registration: URL: https://www.clinicaltrials.gov; Unique identifiers: NCT02224755 and NCT02892955.

Device Profile of the VEST for External Support of SVG Coronary Artery Bypass Grafting: Historical Development, Current Status and Future Directions

A search for strategies to address saphenous vein graft (SVG) failure - the main factor limiting the long-term success of coronary bypass grafting - has led to trialing of external stenting technologies.

AREAS COVERED

The manuscript covers historical development and current status of external scaffolding for the treatment of SVG intimal hyperplasia. Comprehensive literature review and personal communication with VGS leadership, the developer of the VEST device, served as the sources.

EXPERT OPINION

If the external scaffolding concept proves to be successful in mitigating the intimal hyperplasia inherent to arterialized saphenous vein conduits, it could have a dramatic impact on the recurrence of anginal symptoms, the need for repeat revascularization, and the incidence of myocardial infarction following CABG surgery. These laudable sequelae could ultimately convey significant public health repercussions by reducing healthcare resource use and improving the long-term survival and quality of life of CABG recipients.

Concordance of Treatment Effect: An Analysis of The Society of Thoracic Surgeons Intermacs Database

BACKGROUND

The Society of Thoracic Surgeons (STS) Intermacs Registry represents a real-world data source of durable, left ventricular assist devices that can address knowledge gaps not informed through randomized clinical trials. We sought to compare survival with contemporary left ventricular assist device technologies using multiple analytic approaches to assess concordance of treatment effects and to validate prior STS Intermacs observations.

METHODS

Patients (aged > 19 years) enrolled into STS Intermacs between August 2017 - June 2019 were stratified by device type (centrifugal device with hybrid levitation [CF-HL] or full magnetic levitation [CF-FML]). The primary outcome was 1-year survival assessed by three statistical methodologies (multivariable regression, propensity score matching, and instrumental variable analysis).

RESULTS

Of 4,448 patients, 2,012 (45.2%) received CF-HL and 2,436 (54.8%) received CF-FML. One-year survival for CF-FML was 88% vs. 79% for CF-HL (overall p < .001), with a hazard ratio for mortality of 3.18 for CF-HL (p<0.0001) after risk adjustment. With propensity score matching (n=1400 each cohort), 1-year survival was 87% for CF-FML vs. 80% for CF-HL, with a hazard ratio of 3.20 for mortality with CF-HL (p<0.0001) after risk adjustment. With an instrumental variable analysis, the probability of receiving CF-HL was associated with a hazard ratio of 3.11 (p<0.0001).

CONCLUSIONS

Statistical methodology using propensity score matching and instrumental variable analysis increased the robustness of observations derived from real-world data and demonstrates the feasibility of performing comparative effectiveness research using STS Intermacs. These analyses provide additional evidence supporting a survival benefit of CF-FML versus CF-HL.

Prediction of right heart failure after left ventricular assist implantation: external validation of the EUROMACS right-sided heart failure risk score

AIMS

Prediction of right heart failure (RHF) after left ventricular assist device (LVAD) implant remains a challenge. The EUROMACS right-sided heart failure (EUROMACS-RHF) risk score was proposed as a prediction tool for post-LVAD RHF but lacks from large external validation. The aim of our study was to externally validate the score.

METHODS AND RESULTS

From January 2007 to December 2017, 878 continuous-flow LVADs were implanted at three tertiary centres. We calculated the EUROMACS-RHF score in 662 patients with complete data. We evaluated its predictive performance for early RHF defined as either (i) need for short- or long-term right-sided circulatory support, (ii) continuous inotropic support for ≥14 days, or (iii) nitric oxide for ≥48 h post-operatively. Right heart failure occurred in 211 patients (32%). When compared with non-RHF patients, pre-operatively they had higher creatinine, bilirubin, right atrial pressure, and lower INTERMACS class (P < 0.05); length of stay and in-hospital mortality were higher. Area under the ROC curve for RHF prediction of the EUROMACS-RHF score was 0.64 [95% confidence interval (CI) 0.60-0.68]. Reclassification of patients with RHF was significantly better when applying the EUROMACS-RHF risk score on top of previous published scores. Patients in the high-risk category had significantly higher in-hospital and 2-year mortality [hazard ratio: 1.64 (95% CI 1.16-2.32) P = 0.005].

CONCLUSION

In an external cohort, the EUROMACS-RHF had limited discrimination predicting RHF. The clinical utility of this score remains to be determined.

Increasing multiorgan heart transplantation with hepatitis C virus donors in the current-era

The trends and outcomes of multiorgan heart-transplantation (HT) using hepatitis C virus (HCV) donors in the contemporary era are sparsely known. Using UNOS registry, 1322 adult multiorgan-HTs (n = 986 heart-kidney, n = 155 heart-lung, n = 181 heart-liver) between August-2015 and August-2020 were identified, of which 109 were performed using HCV-donors (n = 77 HCV nucleic-acid-amplification testing [NAT] positive irrespective of antibody status [HCV-viremic]; and n = 32 HCV Ab+/NAT-[HCV antibody + nonviremic]). The percentage of HCV-donors used for multiorgan-HT increased from 0% in 2015 to 14% in 2020 (p < 0.001), but there was wide variation across UNOS regions and center volumes. Recipients of multiorgan heart-kidney transplants from HCV-donors (n = 90) and HCV-naïve (HCV Ab-/NAT-) donors (n = 896) had similar 1-year survival using unadjusted and adjusted Cox-proportional hazards-regression models including in propensity-score matched cohorts. Post-HT rates of cardiac-allograft-vasculopathy (5.4% vs 5.8%) and chronic-dialysis (7.3% vs 4.9%) at 1-year were also similar. Use of HCV-donors (HCV-viremic, HCV Ab+ nonviremic) for multiorgan-HT has increased significantly. Encouraging 1-year outcomes in heart-kidney recipients from HCV-donors should support further expansion of heart-kidney transplantation using HCV-donors.

Outflow graft obstruction in patients with the HM 3 LVAD: A percutaneous approach

BACKGROUND

The use of the HeartMate 3 (HM3) left ventricular assist device (LVAD) is expanding. Despite being associated with lower rates of adverse events and increased survival, outflow graft obstruction (OGO) has been reported in patients with HM3. The incidence and best management of this serious complication remain unclear.

METHODS

We describe six cases of HM3 OGO occurring in five patients in our institutional HM3 cohort. Four cases underwent computed tomography angiography and in two percutaneous angiography was directly performed to confirm the diagnosis. In four cases, percutaneous repair of the OG was performed using common interventional cardiology (IC) techniques.

RESULTS

Our institutional incidence of OGO was 7% (event rate of 0.05 per patient year); much higher than the previously reported incidence of 1.6%. All cases occurred in the bend relief covered segment. Only two patients had apparent OG twisting, and in two, OGO occurred despite placement of an anti-twist clip at the time of implant. External compression seems to play a role in most cases. Balloon "graftoplasty" and stent deployment via the femoral artery alleviated the obstruction and normalized LVAD flow in all patients who underwent percutaneous repair. The use of self-expanding stents allowed for downsizing of the procedural access site to 10 Fr. No serious procedure-related complications occurred.

CONCLUSION

OGO is common in HM3 patients, external compression due to biomaterial accumulated surrounding the OG is a common etiology. Percutaneous repair using standard IC techniques is safe and feasible in cases of compression with or without partial twisting.

Primary results of long-term outcomes in the MOMENTUM 3 pivotal trial and continued access protocol study phase: a study of 2200 HeartMate 3 left ventricular assist device implants

AIM

The MOMENTUM 3 pivotal trial established superiority of the HeartMate 3 (HM3) left ventricular assist device (LVAD), a fully magnetically levitated centrifugal-flow pump, over the HeartMate II axial-flow pump. We now evaluate HM3 LVAD outcomes in a single-arm prospective continuous access protocol (CAP) post-pivotal trial study.

METHODS AND RESULTS

We enrolled 2200 HM3 implanted patients (515 pivotal trial and 1685 CAP patients) and compared outcomes including survival free of disabling stroke or reoperation to replace or remove a malfunctioning device (primary composite endpoint), overall survival and major adverse events at 2 years. The 2-year primary endpoint [76.7% vs. 74.8%; adjusted hazard ratio (HR) 0.87, 95% confidence interval (CI) 0.71-1.08, P = 0.21] and overall survival (81.2% vs. 79.0%) were similar among CAP and pivotal cohorts despite sicker patients (more intra-aortic balloon pump use and INTERMACS profile 1) in CAP who were more often intended for destination therapy. Survival was similar between the CAP and pivotal trial in transplant ineligible patients (79.1% vs. 76.7%; adjusted HR 0.89, 95% CI 0.68-1.16, P = 0.38). In a pooled analysis, the 2-year primary endpoint was similar between INTERMACS profiles 1-2 ('unstable' advanced heart failure), profile 3 ('stable' on inotropic therapy), and profiles 4-7 ('stable' ambulatory advanced heart failure) (75.7% vs. 77.6% vs. 72.9%, respectively). The net burden of adverse events was lower in CAP (adjusted rate ratio 0.93, 95% CI 0.88-0.98, P = 0.006), with consequent decrease in hospitalization.

CONCLUSIONS

The primary results of accumulating HM3 LVAD experience suggest a lower adverse event burden and similar survival compared to the pivotal MOMENTUM 3 trial.

Protocol endomyocardial biopsy beyond 6 months-It is time to move on

The optimal duration and frequency of routine surveillance endomyocardial biopsy (EMB) have been questioned in the current era of heart transplantation (HT), where the advances in immunosuppression and donor selection strategies have led to a decline in acute allograft rejection. We investigated the utility of routine EMB beyond 6 months post-HT. A single-center retrospective review was performed on 2963 EMBs from 220 HT recipients over 10 years. Each EMB was categorized into protocol or symptom-triggered biopsy and reviewed for rejection. Heart transplant recipients with ≥2 known risk factors for rejection were designated as an elevated risk group. The majority of rejections occurred within 3 months following HT. The yield of routine protocol EMBs was significantly lower than symptom-triggered EMBs, not only during the first 6 months post-HT (1.6% vs. 33.3%, P < .0001), but more so during the 6-12 months (0.1% vs 83.0%, P < .0001). A similar pattern was observed in heart transplant recipients at both elevated and standard risk for rejection. In conclusion, EMB was found to be a low-yield screening modality for rejection beyond 6 months post-HT.

Association of Clinical Outcomes With Left Ventricular Assist Device Use by Bridge to Transplant or Destination Therapy Intent: The Multicenter Study of MagLev Technology in Patients Undergoing Mechanical Circulatory Support Therapy With HeartMate 3 (MOMENTUM 3) Randomized Clinical Trial

Question

In patients with advanced heart failure, do outcomes with left ventricular assist device implantation differ by the initial intended goal of therapy as a bridge to transplant or destination therapy?

Findings

In this randomized clinical trial, the composite end point of survival free of disabling stroke or reoperation to remove or replace a malfunctioning device at 2 years was significantly better with the magnetically levitated centrifugal-flow HeartMate 3 than the mechanical-bearing axial-flow HeartMate II, irrespective of preimplant therapeutic intent. Event-free survival was not different between patients in the bridge to transplant or destination therapy groups treated with the HeartMate 3 pump.

Meaning

Per this randomized clinical trial, use of categorizations based on current or future transplant eligibility should be abandoned in favor of a single treatment indication for use of left ventricular assist devices.

Importance

Left ventricular assist devices (LVADs) are well established in the treatment of advanced heart failure, but it is unclear whether outcomes are different based on the intended goal of therapy in patients who are eligible vs ineligible for heart transplant.

Objective

To determine whether clinical outcomes in the Multicenter Study of MagLev Technology in Patients Undergoing Mechanical Circulatory Support Therapy With HeartMate 3 (MOMENTUM 3) trial differed by preoperative categories of bridge to transplant (BTT) or bridge to transplant candidacy (BTC) vs destination therapy (DT).

Design, Setting, and Participants

This study was a prespecified secondary analysis of the MOMENTUM 3 trial, a multicenter randomized clinical trial comparing the magnetically levitated centrifugal-flow HeartMate 3 (HM3) LVAD to the axial-flow HeartMate II (HMII) pump. It was conducted in 69 centers with expertise in managing patients with advanced heart failure in the United States. Patients with advanced heart failure were randomized to an LVAD, irrespective of the intended goal of therapy (BTT/BTC or DT).

Main Outcomes and Measures

The primary end point was survival free of disabling stroke or reoperation to remove or replace a malfunctioning device at 2 years. Secondary end points included adverse events, functional status, and quality of life.

Results

Of the 1020 patients with implants (515 with HM3 devices [50.5%] and 505 with HMII devices [49.5%]), 396 (38.8%) were in the BTT/BTC group (mean [SD] age, 55 [12] years; 310 men [78.3%]) and 624 (61.2%) in the DT group (mean [SD] age, 63 [12] years; 513 men [82.2%]). Of the patients initially deemed as transplant ineligible, 84 of 624 patients (13.5%) underwent heart transplant within 2 years of LVAD implant. In the primary end point analysis, HM3 use was superior to HMII use in patients in the BTT/BTC group (76.8% vs 67.3% for survival free of disabling stroke and reoperation; hazard ratio, 0.62 [95% CI, 0.40-0.94]; log-rank P = .02) and patients in the DT group (73.2% vs 58.7%; hazard ratio, 0.61 [95% CI, 0.46-0.81]; log-rank P < .001). For patients in both BTT/BTC and DT groups, there were not significantly different reductions in rates of pump thrombosis, stroke, and gastrointestinal bleeding with HM3 use relative to HMII use. Improvements in quality of life and functional capacity for either pump were not significantly different regardless of preimplant strategy.

Conclusions and Relevance

In this trial, the superior treatment effect of HM3 over HMII was similar for patients in the BTT/BTC or DT groups. It is possible that use of arbitrary categorizations based on current or future transplant eligibility should be clinically abandoned in favor of a single preimplant strategy: to extend the survival and improve the quality of life of patients with medically refractory heart failure.

Trial Registration

ClinicalTrials.gov identifier: NCT02224755

Comparative analysis of regional outcomes and adverse events after continuous-flow left ventricular assist device implantation: An IMACS analysis

INTRODUCTION

Regional outcomes after implantation of continuous-flow left ventricular assist devices (LVADs) have not been described. We examined differences in patient selection, survival, and adverse events across 3 geographic regions of the world: the Americas, Asia-Pacific, and Europe.

METHODS

Using data from The International Society for Heart and Lung Transplantation Mechanically Assisted Circulatory Support registry, all adult patients implanted with a continuous-flow LVADs were included in this International Society for Heart and Lung Transplantation Mechanically Assisted Circulatory Support analysis (n = 15,560), of whom, 9,988 (64%) received axial-flow devices and 5,572 (36%) received centrifugal-flow devices.

RESULTS

There were significant interregional differences in the rate of implantation of patients aged >70 years (Americas: 14%, Asia-Pacific: 1%, Europe: 5%; p < 0.0001), morbidly obese (Americas: 5%, Asia-Pacific: 1%, Europe: 1%; p < 0.0001), male (Americas: 79%, Asia-Pacific: 77%, Europe: 85%; p < 0.0001), and implanted as destination therapy (Americas: 48%, Asia-Pacific: 4%, Europe: 22%; p < 0.0001). The rates of centrifugal pump usage varied by region (Americas: 30%, Asia-Pacific: 34%, Eu: 74%; p < 0.0001). Survival rates varied by region and the type of pump flow, with survival at 12 and 48 months (axial flow vs centrifugal flow) being 82% vs 82% and 52% vs 53 in Americas; 92% vs 86% and 83% vs 74% in Asia-Pacific; and 80% vs 75% and 69% vs 53% in Europe, respectively (regional survival p < 0.0001).

CONCLUSION

There are marked global differences in LVAD recipient characteristics, device utilization, and post-operative care. These heterogeneities along with differences in patient management and transplantation rates may impact long-term survival. Regional differences in adverse event incidence warrant further investigation.

Impact of left ventricular assist device implantation on mitral regurgitation: An analysis from the MOMENTUM 3 trial

BACKGROUND

Mitral regurgitation (MR) determines pathophysiology and outcome in advanced heart failure. The impact of left ventricular assist device (LVAD) placement on clinically significant MR and its contribution to long-term outcomes has been sparsely evaluated.

METHODS

We evaluated the effect of clinically significant MR on patients implanted in the MOMENTUM 3 trial with either the HeartMate II (HMII) or the HeartMate 3 (HM3) at 2 years. Clinical significance was defined as moderate or severe grade MR determined by site-based echocardiograms.

RESULTS

Of 927 patients with LVAD implants without a prior or concomitant mitral valve procedure, 403 (43.5%) had clinically significant MR at baseline. At 1-month of support, residual MR was present in 6.2% of patients with HM3 and 14.3% of patients with HMII (relative risk = 0.43; 95% CI, 0.22-0.84; p = 0.01) with a low rate of worsening at 2 years. Residual MR at 1-month post-implant did not impact 2-year mortality for either the HM3 (hazard ratio [HR],1.41; 95% CI, 0.52-3.89; p = 0.50) or HMII (HR, 0.91; 95% CI, 0.37-2.26; p = 0.84) LVAD. The presence or absence of baseline MR did not influence mortality (HM3 HR, 0.86; 95% CI, 0.56-1.33; p = 0.50; HMII HR, 0.81; 95% CI, 0.54-1.22; p = 0.32), major adverse events or functional capacity. In multivariate analysis, severe baseline MR (p = 0.001), larger left ventricular dimension (p = 0.002), and implantation with the HMII instead of the HM3 LVAD (p = 0.05) were independently associated with an increased likelihood of persistent MR post-implant.

CONCLUSIONS

Hemodynamic unloading after LVAD implantation improves clinically significant MR early, sustainably, and to a greater extent with the HM3 LVAD. Neither baseline nor residual MR influence outcomes after LVAD implantation.

Effect of aspirin dose on hemocompatibility-related outcomes with a magnetically levitated left ventricular assist device: An analysis from the MOMENTUM 3 study

BACKGROUND

Aspirin (ASA) anti-platelet therapy is mandated with left ventricular assist devices (LVADs) to prevent hemocompatibility-related adverse events (HRAEs). However, the optimal dose of ASA with HeartMate 3 (HM3) LVAD is unknown.

METHODS

In an exploratory analysis of HM3-supported patients in the MOMENTUM 3 study (NCT02224755), 2 groups were analyzed: usual-dose (325 mg) and low-dose (81 mg) ASA with anti-coagulation targeted to an international normalized ratio of 2.0 to 3.0. Exclusion criteria included patients not receiving either ASA 81 mg or 325 mg, those with HRAEs ≤7 days after device implantation, and those receiving >1 anti-platelet agent. The primary end-point was survival free from HRAEs (non-surgical bleeding, pump thrombosis, stroke, and peripheral arterial thromboembolic events) at 2 years.

RESULTS

Overall, 321 HM3 patients (usual-dose: n = 141, low-dose: n = 180) were included in this analysis. Usual-dose group patients were younger (57 ± 13 vs 60 ± 12 years, p = 0.035) and less often assigned destination therapy (55% vs 67%, p = 0.029) than low-dose ASA. At 2 years, a similar proportion of patients in the usual- and low-dose groups (43.4% vs 45.3%, p = 0.94) met the primary end-point. There were no differences in survival free from hemorrhagic (usual-dose: 54.4% vs low-dose: 51.7%, p = 0.42) or thrombotic (usual-dose: 76.8% vs low-dose: 75.7%, p = 0.92) events.

CONCLUSIONS

Usual- and low-dose ASA revealed similar rates of bleeding and thrombotic events in HM3 LVAD-supported patients within the MOMENTUM 3 trial. Whether ASA therapy provides any meaningful therapeutic effect in patients treated by the HM3 LVAD remains to be determined.

Cardiac Transplantation Using Hearts With Transient Dysfunction: Role of Takotsubo-Like Phenotype

BACKGROUND

The impact of different types of regional wall motion abnormalities (RWMAs), including the Takotsubo syndrome-like (TTS-like) phenotype, on posttransplant outcomes when using donor hearts with transient left ventricular systolic dysfunction (LVSD) is unknown. We evaluated the prevalence, clinical characteristics, and prognostic association of different RWMAs including TTS-like hypokinesis and posttransplant outcomes when using donor hearts with transient LVSD.

METHODS

From all adult (≥18 years) heart transplants in United Network of Organ Sharing between January 2007 and September 2015, we identified 472 donor hearts with improving or transient LVSD, defined as left ventricular ejection fraction ≤ 40% on initial transthoracic echocardiogram (TTE) that improved to ≥50% on follow-up TTE during donor evaluation. These improved LVSD donors were then subdivided into 3 groups based on RWMAs on the initial TTE, TTS-like (49, 10.38%), non-TTS RWMAs (74, 15.68%), and diffuse global hypokinesis (349, 73.94%), and compared for baseline characteristics and posttransplant outcomes with follow up until June 2018.

RESULTS

Donors with TTS-like LVSD were older and more likely to be female. The type of RWMA on initial TTE (including TTS-like) of transient LVSD donor hearts was not associated with 1-year or 5-year posttransplant mortality. Posttransplant functional status scores of recipients (at 1 year) and donor left ventricular ejection fraction (at median follow-up of 3.6 years) improved in all 3 subgroups. Rates of stroke or pacemaker predischarge were also similar.

CONCLUSIONS

In the largest analysis of transplanted donor hearts with transient LVSD, 1 in 4 had RWMAs on the initial TTE, but this was not associated with adverse posttransplant outcomes. Donor hearts with initial LVSD should be pursued irrespective of TTS-like hypokinesis or other RWMAs.

Hemolysis and Nonhemorrhagic Stroke During Venoarterial Extracorporeal Membrane Oxygenation

BACKGROUND

Hemolysis, even at low levels, activates platelets to create a prothrombotic state and is common during mechanical circulatory support. We examined the association of low-level hemolysis (LLH) and nonhemorrhagic stroke during venoarterial extracorporeal membrane oxygenation (VA ECMO) support.

METHODS

A single-center retrospective review of all adult patients placed on VA ECMO from January 2012 to September 2017 was conducted. To determine the association between LLH and nonhemorrhagic stroke, patients were categorized as those with and without LLH. LLH was defined by 48-hour plasma free hemoglobin (PFHb) of 11 to 50 mg/dL after VA ECMO implantation.

RESULTS

Of 201 patients who underwent VA ECMO placement, 150 (75%) met inclusion criteria and comprised the study population. They were 55 ± 14 years of age and 50 (33%) were women. Sixty-two (41%) patients had LLH. Patients with LLH had a higher likelihood of incident nonhemorrhagic stroke during VA ECMO support (20 [32%] versus 4 [5%]; adjusted hazard ratio [HR], 7.6; 95% confidence interval [CI], 2.2 to 25.9; p = 0.001). The severity of LLH was associated with an incrementally higher likelihood of a nonhemorrhagic stroke (PFHb 26 to 50 mg/dL: HR, 11.3; 95% CI, 3.6 to 35.1; p = 0.001; PFHb 11 to 25 mg/dL: HR, 4.4; 95% CI, 1.36 to 14.85; p = 0.014) in comparison with no LLH. Those with LLH had a 2-fold greater increase in mean platelet volume after VA ECMO placement (0.98 ± 1.1 fL versus 0.49 ± 0.96 fL; p = 0.03). Patients with a nonhemorrhagic stroke had a higher operative mortality (20 [83%] versus 57 [45%]; adjusted HR, 3.1; 95% CI, 1.8 to 5.3; p < 0.001).

CONCLUSIONS

Hemolysis at low levels during VA ECMO support is associated with subsequent nonhemorrhagic stroke.