Characterizing Adaptive Changes and Patient Survival After 2018 Donor Allocation Restructuring: A UNOS Database Analysis.

PURPOSE: We sought to characterize adaptive changes to the revised United Network for Organ Sharing donor heart allocation policy and estimate long-term survival trends for heart transplant (HTx) recipients. METHODS: Patients listed for HTx between October 17, 2013 and September 30, 2021 were identified from the United Network for Organ Sharing database, and stratified into pre- and postpolicy revision groups. Subanalyses were performed to examine trends in device utilization for extracorporeal membranous oxygenation (ECMO), durable left ventricular assist device (LVAD), intra-aortic balloon pump (IABP), microaxial support (Impella), and no mechanical circulatory support (non-MCS). Survival data post-HTx were fitted to parametric distributions and extrapolated to 5 years. RESULTS: We identified 27,523 HTx waitlist candidates during the study period, most of whom (n = 16,376) were waitlisted in the prepolicy change period. Overall, 19,554 patients underwent HTx during the study period (pre: 12,037 and post: 7517). Listings increased after the policy change for ECMO ( P < 0.01), Impella ( P < 0.01), and IABP ( P < 0.01) patients. Listings for LVAD ( P < 0.01) and non-MCS ( P < 0.01) patients decreased. HTx increased for ECMO ( P < 0.01), Impella ( P < 0.01), and IABP ( P < 0.01) patients after the policy change and decreased for LVAD ( P < 0.01) and non-MCS ( P < 0.01) patients. Waitlist survival increased for the overall ( P < 0.01), ECMO ( P < 0.01), IABP ( P < 0.01), and non-MCS ( P < 0.01) groups. Waitlist survival did not differ for the LVAD ( P = 0.8) and Impella ( P = 0.1) groups. Post-transplant survival decreased for the overall ( P < 0.01), LVAD ( P < 0.01), and non-MCS ( P < 0.01) populations. CONCLUSIONS: Allocation policy revisions have contributed to greater utilization of ECMO, Impella, and IABP, decreased utilization of LVADs and non-MCS, increased waitlist survival, and decreased post-HTx survival.

Outcomes of outflow graft stenting in HeartMate 3 left ventricular assist devices: A systematic review and individual patient data meta-analysis.

PURPOSE: LVAD outflow graft stenosis continues to remain prevalent with a high complication rate. We sought to pool the existing evidence on indications, utilization patterns, and outcomes of transcatheter interventions for outflow graft stenosis in the HeartMate 3 LVAD. METHODS: An electronic search was performed to identify all studies in the English literature reporting on HeartMate 3 LVAD outflow graft stenting. Patient-level data were extracted for analysis. RESULTS: Thirteen published reports and one unpublished case comprising a total of 28 patients were included. Median patient age was 68.5 years [Interquartile range: 58, 71] and 25.9% (7/27) were female. Dyspnea [60.7% (17/28)] was the most common presenting symptom. Low flow alarms were present in 60% (15/25) of patients. Findings included external compression [35.7% (10/28)], graft twist [21.4% (6/28)], graft twist and external compression [14.3% (4.28)], intraluminal thrombus [10.7% (3/28)], graft twist and intraluminal thrombus [3.6% (1/28)], and pseudoaneurysm of outflow graft [3.6% (1/28)]. Median time from LVAD implantation to stenting was 2.1 years [1.4, 3]. Immediate flow normalization after stenting was observed in 85.7% (24/28). The 30-day mortality was 12% (3/25). Overall mortality was 12% (3/25) at a median follow-up of 3.9 months [1, 17]. CONCLUSION: Outflow graft stenting in the HeartMate 3 LVAD appears to be a reasonable treatment option for outflow graft stenosis, with low overall rates of complications and mortality. Further refinement of indications and approaches may improve outcomes.

Determinants of pulmonary hypertension in patients with end-stage kidney disease and arteriovenous access.

BACKGROUND: Pulmonary Hypertension (PH) is a sequela of arteriovenous (AV) fistulas (AVF) or AV grafts (AVG) in patients with end-stage kidney disease (ESKD) due to the creation of shunt physiology and increased pulmonary blood flow. PH has been consistently associated with increased mortality but there is a paucity of data regarding management. RESEARCH QUESTION: The objective of this study was to identify risk factors and outcomes in patients who develop PH after AVF or AVG creation for hemodialysis access. METHODS: Using the United States Renal Data System, we identified all patients over age 18 initiated on dialysis from 2012-2019 who did not receive renal transplant. We identified a) the predictors of PH in patients with ESKD on hemodialysis; b) the independent mortality risk associated with development of PH. RESULTS: We identified 478,896 patients initiated on dialysis from 2012-2019 of whom 27,787 (5.8 %) had a diagnosis of PH. The median age was 65 (IQR: 55-74) years and 59.1 % were male. Reduced ejection fraction, any congestive heart failure, obstructive sleep apnea, and female sex were the strongest predictors of PH diagnosis. Both AVG and AVF were also associated with an increased rate of PH diagnosis compared to catheter-based dialysis (p < 0.001). PH portended a poor prognosis and was associated with significantly increased mortality (p < 0.001). CONCLUSIONS: Patients with AVF or AVG should be screened using echocardiography prior to creation and monitored with serial echocardiography for the development of PH, and if present, considered for revision of the AVA. This is also the first study to identify that AVG are a risk factor for PH in dialysis patients.

Association of Heart Transplant Volume with Presence of Lung Transplant Programs and Heart Transplant's SRTR One-year Survival Rating.

BACKGROUND: Several factors affect heart transplant (HTx) and lung transplant (LTx) program outcomes. Variabilities in institutional and community characteristics have been shown to influence survival. At present, half of HTx centers in the United States do not possess a concomitant LTx program. This study sought to better understand the characteristics of HTx with and without LTx programs. METHODS: Nationwide transplant data were collected from the Scientific Registry of Transplant Recipients (SRTR) in August 2020. SRTR star rating ranges from tier 1 (lowest) to tier 5 (highest). HTx volumes and SRTR star ratings for survival were compared between the centers with heart-only (H0) programs and the centers with heart-lung (HL) programs. RESULTS: SRTR star ratings were available for 117 transplant centers with one or more HTx reported. The median number of HTx performed over 1 year was 16 (interquartile range [IQR]: 2-29). The number of HL centers (n = 67, 57.3%) were comparable to H0 centers (n = 50, 42.7%; p = 0.14). The HTx volume at the HL centers (28 [IQR: 17-41]) exceeded the HTx volume at the H0 centers (13 [IQR: 9-23]; p < 0.01), but were comparable to the LTx volume at the HL centers (31 [IQR: 16-46]; p = 0.25). The median HTx one-year survival rating was 3 (IQR: 2-4) at both the H0 and HL centers (p = 0.85). The HTx and LTx volumes were positively associated with the respective 1-year survivals (p < 0.01). CONCLUSION: While the presence of an LTx program is not directly associated with HTx survival, it has a positive association with the HTx volume. The HTx and LTx volumes are positively associated with the 1-year survival.

Transcatheter Aortic Valve Implantation in Cardiac Amyloidosis and Aortic Stenosis.

Aortic stenosis (AS) and cardiac amyloidosis (CA) occur concomitantly in a significant number of patients and portend a higher risk of all-cause mortality. Previous studies have investigated outcomes in patients with concomitant CA/AS who underwent transcatheter aortic valve implantation (TAVI) versus medical therapy alone, but no evidence-based consensus regarding the ideal management of these patients has been established. Medline, Scopus, and Cochrane Central Register of Controlled Trials were systematically searched to identify relevant studies. Methodologic bias was assessed using the modified Newcastle-Ottawa scale for observational studies. A total of 4 observational studies comprising 83 patients were included. Of these, 45 patients (54%) underwent TAVI, whereas 38 (46%) were managed conservatively. Of the 3 studies that included baseline characteristics by treatment group, 30% were women. The risk of all-cause mortality was found to be significantly lower in patients who underwent TAVI than those treated with conservative medical therapy alone (odds ratio 0.24, 95% confidence interval 0.08 to 0.73). In conclusion, this meta-analysis suggests a lower risk of all-cause mortality in patients with CA with AS who underwent TAVI than those managed with medical therapy alone.

Adverse outcomes of atrial fibrillation ablation in heart failure patients with and without cardiac amyloidosis: a Nationwide Readmissions Database analysis (2015-2019).

Aims: Atrial fibrillation (AF) in patients with cardiac amyloidosis (CA) has been linked with a worse prognosis. The current study aimed to determine the outcomes of AF catheter ablation in patients with CA. Methods and results: The Nationwide Readmissions Database (2015-2019) was used to identify patients with AF and concomitant heart failure. Among these, patients who underwent catheter ablation were classified into two groups, patients with and without CA. The adjusted odds ratio (aOR) of index admission and 30-day readmission outcomes was calculated using a propensity score matching (PSM) analysis. A total of 148 134 patients with AF undergoing catheter ablation were identified on crude analysis. Using PSM analysis, 616 patients (293 CA-AF, 323 non-CA-AF) were selected based on a balanced distribution of baseline comorbidities. At index admission, AF ablation in patients with CA was associated with significantly higher adjusted odds of net adverse clinical events (NACE) [adjusted odds ratio (aOR) 4.21, 95% CI 1.7-5.20], in-hospital mortality (aOR 9.03, 95% CI 1.12-72.70), and pericardial effusion (aOR 3.30, 95% CI 1.57-6.93) compared with non-CA-AF. There was no significant difference in the odds of stroke, cardiac tamponade, and major bleeding between the two groups. At 30-day readmission, the incidence of NACE and mortality remained high in patients undergoing AF ablation in CA. Conclusion: Compared with non-CA, AF ablation in CA patients is associated with relatively higher in-hospital all-cause mortality and net adverse events both at index admission and up to 30-day follow-up.

COVID-19 associated development of antibody mediated rejection in orthotopic heart transplantation patients.

Solid organ transplant candidates encountered increased wait times and mortality rates during the coronavirus 2019 (COVID-19) pandemic. Despite improvement in medical management and vaccination efficacy, this patient population remains at increased risk for complications post COVID-19 including organ rejection. We describe the development of antibody mediated rejection with or without cellular rejection in heart transplant (HT) recipients and previous COVID-19 infection or vaccination. Although centers have changed their management of outpatient follow-up for orthotopic heart transplant patients, little is known on surveillance of rejection and management of HT recipients after COVID-19 infection. We recommend frequent surveillance for rejection or allograft dysfunction after COVID-19 infection. We have adopted a transplant surveillance protocol for HT recipients with COVID-19 infection, given our recent experience with transplanted patients affected of COVID-19.

PCI for acute myocardial infarction in patients with a pre-existing LVAD, does it improve survival?

BACKGROUND: It is well established that percutaneous coronary intervention (PCI) is a life-saving procedure for acute myocardial infarction (AMI) in the general population and is guideline-recommended for both STEMI and NSTEMI. There is little literature regarding its use in patients with a pre-implanted Left Ventricular Assist Device (LVAD). METHODS: We retrospectively analyzed data from the National Inpatient Sample (NIS) Database to select all US adult patients (>18 years) with an LVAD diagnosed with an AMI divided into two groups; those who received PCI during the hospitalization and those who did not. RESULTS: A total of 3722 LVAD patients with AMI were identified, of these 17% of patients received PCI and 83% did not. After propensity matching of LVAD patients with AMI, there were 626 patients who received PCI and 623 who did not. Of patients receiving PCI, 37.5% had a STEMI while 29.7% of patients who did not receive PCI had STEMI. Rates of kidney injury (36.5% vs. 43.3%, OR 0.75, 95% CI 0.60-0.94, p = 0.016), sepsis (3.2% vs. 11.4%, OR 0.26, 95% CI 0.15-0.43, p < 0.001), cardiogenic shock (44.1% vs. 50.4%, OR 0.78, 95% CI 0.62-0.97, p = 0.03) and mortality (17.4% vs. 28.9%, OR 0.52, 95% CI 0.40-0.68, p < 0.001) were all better for patients receiving PCI. Vascular complications (1.4% vs. 0%, p = 0.008) and intracerebral hemorrhage (ICH) (1.6% vs. 0, p = 0.004) were both more common in the group receiving PCI. CONCLUSIONS: In this study, patients supported by LVAD with AMI had an elevated risk of mortality compared to generally accepted mortality rates of patients without LVAD. In this analysis PCI was associated with a decreased risk of mortality, cardiogenic shock, and kidney injury while increasing the risk for vascular complications and intracranial hemorrhage.

Catheter ablation in patients with atrial fibrillation and heart failure with preserved ejection fraction: A systematic review and meta-analysis.

Background: Catheter ablation for atrial fibrillation (AF) is a proven alternative to pharmacologic rhythm control in patients with heart failure with reduced ejection fraction (HFrEF). Whether outcomes differ in patients with heart failure with preserved ejection fraction (HFpEF) is of interest. Methods: Medline, Scopus, and Cochrane Central Register of Controlled Trials were systematically searched to identify relevant studies. Primary efficacy outcomes of interest include atrial arrythmia recurrence and repeat ablation. Harm outcomes of interest include all-cause mortality, all-cause hospitalizations, cardiovascular hospitalizations, stroke/transient ischemic attack, and cardiac tamponade. Results: We included 7 observational studies comprising 2554 patients with HFpEF who underwent catheter ablation for AF. When comparing patients with HFpEF versus without HF, there was no significant difference in atrial arrhythmia recurrence (risk ratio [RR] 1.39; 95% confidence interval [CI] 0.91-2.13), stroke or transient ischemic attack (TIA) (RR 0.47; 95% CI 0.03-6.54), or cardiac tamponade (RR 1.20; 95% CI 0.12-12.20). When comparing patients with HFpEF versus HFrEF, there was no significant difference in atrial arrhythmia recurrence (RR 1.12; 95% CI 0.92-1.37), repeat ablation (RR 1.19; 95% CI 0.74-1.93), all-cause mortality (RR 0.87; 95% CI 0.67-1.13), all-cause hospitalizations (RR 1.10; 95% CI 0.94-1.30), cardiovascular hospitalizations (RR 0.83; 95% CI 0.69-1.01), stroke or TIA (RR 0.81; 95% CI 0.29-2.25), or cardiac tamponade (RR 0.98; 95% CI 0.19-5.16). Conclusions: Non-randomized studies suggest that catheter ablation for AF in patients with HFpEF is associated with similar arrythmia-free survival and safety profile when compared to patients with HFrEF or without heart failure.

Percutaneous Decommissioning 11 Years After Initial CF-LVAD Placement.

An 80-year-old man with severe nonischemic cardiomyopathy status post left ventricular assist device (LVAD) placement 11 years prior presented for recurrent LVAD alarms from internal driveline fracture. Given his partial myocardial recovery and his preference to avoid surgical procedures, percutaneous LVAD decommissioning was performed by occlusion of the outflow graft and subsequently driveline removal. (Level of Difficulty: Advanced.).

Giant ventral hernia following left ventricular assist device bridge to heart transplantation.

Ventral hernias following left ventricular assist device (LVAD) placement are rare. With the improvement in technology, and miniaturization of devices associated with intrapericardial placement, these complications have largely been abolished. The mere presence of a large ventral hernia should not exclude recipients from being candidates for orthotopic heart transplantation.

Impact of ventricular arrhythmia on LVAD implantation admission outcomes.

INTRODUCTION: Ventricular arrhythmias (VAs) are common after left ventricular assist device (LVAD) implantation though data are mixed on whether these events have an impact on mortality. METHODS: The National Inpatient Sample (NIS) database from 2002-2019 was queried for LVAD implantation admissions. Secondary ICD codes were analyzed to assess for the occurrence of VAs during this admission. Propensity score matching (PSM) was used to control for confounding variables between those with versus without VAs. RESULTS: The NIS database from 2002-2019 contained 43 936 admissions with LVAD implantation. VAs occurred in 19 985 (45.4%) patients. After PSM, the study cohort consisted of 39 989 patients, 19 985 (50.0%) of which had a secondary diagnosis of VA during the admission. When compared to those without VA, those with VA were at no higher risk for in-hospital mortality (adjusted odds ratio 1.011, 99.9% CI 0.956-1.069, p = 0.699). Those with a VA were at higher risk for cardiogenic shock and requiring mechanical ventilation, tracheostomy, and percutaneous endoscopic gastrostomy placement. Patients with a VA were also at lower risk for device thrombosis. Conversely, the VA group was at no higher risk for stroke. In comparing trends from 2002 to 2019, the incidence of VAs has increased, while the mortality rate of those with and without VAs has decreased during this same period. CONCLUSION: In this retrospective study of the NIS database, VAs were common (45.4%) during the LVAD implantation admission. However, the occurrence of VAs during the implantation admission did not alter in-hospital mortality. More longitudinal studies are required to assess the long-term impact of VAs on mortality. In comparing trends from 2002-2019, the incidence of VAs has increased, while the mortality rate of those with and without VAs has decreased.

COVID-19 Vaccination-Induced Cardiomyopathy Requiring Permanent Left Ventricular Assist Device.

Myocarditis was identified as a rare but serious adverse event that can occur after mRNA-based coronavirus disease 2019 (COVID-19) vaccination, particularly in young males. During the COVID-19 pandemic, we report a case of a young obese male without multiple comorbidities who presented with abdominal pain and was found to have severe myocarditis/cardiomyopathy, which was likely due to mRNA-based COVID-19 vaccination. The patient had left ventricular assist device (LVAD) implantation during hospitalization. Myocarditis/cardiomyopathy may be a rare complication of the mRNA-based COVID vaccine; however, one should maintain a high index of suspicion that these vaccines may cause irreversible cardiomyopathy if the patient had prior COVID-19 infection.

Clinical Outcome of TAVR vs. SAVR in Patients With Cardiac Amyloidosis.

Data regarding the clinical outcomes of transcatheter aortic valve replacement (TAVR) vs. surgical aortic valve replacement (SAVR) in cardiac amyloidosis are lacking. Our study aimed to look at the clinical outcomes of TAVR vs. SAVR in patients with cardiac amyloidosis. METHOD: We queried the National Inpatient Sample database for the years 2009-2014 using validated ICD-9-CM codes for TAVR and SAVR. Propensity score matching (1:1; PSM) was performed and in-hospital outcomes were compared between matched cohorts. RESULTS: Before PSM, the TAVR group had a higher hospitalization cost ($59,192 vs. $56,171.1, p = 0.001) and in-hospital mortality (4.24% vs. 3.27%, p = 0.001) compared to the SAVR group. After PSM, mortality (41.3% vs. 5.81%, p = 0.001) and hospitalization cost ($5907 vs. $6280, p = 0.001) was higher in the SAVR group. Length of stay was shorter in the TAVR group compared to SAVR group before (8.7 vs 11.4 p = 0.001) and after (8.7 vs 0.13.7, p = 0.001) PSM. After PSM, the incidence of acute myocardial infarction (10.10% vs. 17.57%, p = 0.001), acute kidney injury (20.67% vs. 31.40%, p = 0.001) and major bleeding (39.18% vs. 47.90%, p = 0.001) were higher in the SAVR group while the TAVR group had a higher incidence of the stroke (12.47% vs. 11.97%, p = 0.001), vascular complication (14.59% vs. 12.97%, p = 0.001), and permanent pacemaker implantation (10.45% vs. 8.48%, p = 0.001). CONCLUSION: In CA patients, in-hospital mortality and hospitalization costs were higher in the SAVR group than in the TAVR group, while the length of stay was shorter in the TAVR group.

Assessing donor-recipient size metrics for heart transplant outcomes: UNOS database analysis.

STUDY: There is no widely accepted donor to recipient size-match metric to predict outcomes in cardiac transplant. The predictive ability of size-match metrics has not been studied when recipients are stratified by heart failure etiology. We sought to assess the performance of commonly used size metrics to predict survival after heart transplant, accounting for restrictive versus non-restrictive pathology. METHODS: The UNOS registry was queried from 2000 to 2017 for all primary isolated heart transplants. Donor-recipient ratios were calculated for commonly used size metrics and their association with survival was assessed using continuous, nonlinear analysis. RESULTS: 29 817 patients were identified. Height (P < .001), predicted heart mass (PHM) (P = .003), ideal body weight (IBW) (P < .001) and body mass index (BMI) (P = .003) ratios were significantly associated with survival, while weight and body surface area (BSA) ratios were not. When stratified, only BMI ratio retained significance for both restrictive (P = .051) and non-restrictive (P = .003) subsets. Recipients with restrictive etiology had increased risk of mortality with both a lower and higher BMI ratio. CONCLUSIONS: While many metrics show association with survival in the non-restrictive subset, BMI is the only metric that retains significance in the restrictive subset. Recipients with restrictive and non-restrictive etiologies of heart failure tolerate size mismatch differently.

Cardiac transplantation after heparin-induced thrombocytopenia: A systematic review.

PURPOSE: Heparin-induced thrombocytopenia (HIT) presents a unique challenge in patients requiring orthotopic heart transplantation (OHT). We sought to pool the existing evidence in a systematic review. METHODS: Electronic search was performed to identify all relevant studies on OHT in patients with HIT. Patient-level data for 33 patients from 21 studies were extracted for statistical analysis. RESULTS: Median patient age was 51 [IQR 41, 55] years, with 75.8% (25/33) males. All patients had a clinical diagnosis of HIT, and anti-PF4/Heparin antibodies were positive in 87.9% (29/33). Median lowest reported platelet count was 46 × 109 /L [27.2, 73.5]. Intraoperatively, 61% (20/33) of patients were given unfractionated heparin (UFH), while 39% (13/33) were given alternative anticoagulants. The alternative agent subgroup required more antifibrinolytics [54% (7/13) vs 10% (2/20), P = .02] and clotting factors [69.2% (9/13) vs 15.0% (3/20), P < .01]. Perioperative thrombosis occurred more [53.8% (7/13) vs 0% (0/20, P < .01) in alternate agent subgroup. More patients in the alternate agent subgroup required post-operative transfusions [54% (7/13) vs 0% (0/20), P < .01]. Thirty-day mortality of 15.2% (5/33) was comparable between the subgroups. CONCLUSION: Heparin use during OHT may be associated with less adverse effects compared to use of other anticoagulants with no difference in 30-day mortality.

3 Cases of Superior Vena Cava Syndrome Following Percutaneous Right Ventricular Assist Device Placement.

We present 3 cases of superior vena cava (SVC) syndrome following percutaneous right ventricular assist device (RVAD) placement. Each case underscores the importance of early recognition of SVC syndrome in patients with percutaneous RVAD insertion via the internal jugular vein and calls for heightened awareness of device-associated complications. (Level of Difficulty: Advanced.).