Citations

Background: Heart transplantation (HT) remains the definitive therapy for end-stage heart failure, yet rejection and cardiac allograft vasculopathy (CAV) continue to limit long-term outcomes. Beyond donor-specific HLA antibodies, non-HLA antibodies, particularly anti-angiotensin II type 1 receptor antibodies (AT1R-Abs), have been implicated in allograft injury, but published findings are heterogeneous. Aim: The aim of this study is to systematically evaluate the evidence linking AT1R gene expression and anti-AT1R antibodies with key post-heart transplant outcomes. Methods: We conducted a systematic review in accordance with PRISMA guidelines. Scopus, PubMed, Web of Science, and the Cochrane Library were searched (December 2025) for cohort and case–control studies evaluating AT1R gene expression and/or AT1R-Ab status in HT recipients and their association with post-transplant outcomes. Two reviewers independently screened studies, extracted data, and assessed risk of bias using the NIH Quality Assessment Tool. Results: Twelve studies encompassing 951 recipients met the inclusion criteria. Five studies evaluated AT1R mRNA expression, reporting variable patterns: several observed reduced AT1R/AT2R transcription after transplantation without clear clinical correlation, whereas others associated higher donor or recipient AT1R expression with transplant coronary artery disease and recurrent rejection. AT1R-Ab prevalence varied widely and appeared to increase after mechanical circulatory support, with substantial seroconversion reported during LVAD support in initially antibody-negative patients. Associations between AT1R-Ab and acute cellular rejection and antibody-mediated rejection were inconsistent across studies, and survival findings were inconclusive; however, some reports linked elevated AT1R-Abs to poorer long-term freedom from adverse events. Evidence regarding CAV was mixed, with signals of increased vasculopathy risk in some cohorts but not others. Conclusions: Current evidence suggests a potential role for AT1R expression and AT1R-Abs in cardiac allograft dysfunction, including rejection phenotypes and vasculopathy. Larger prospective studies with harmonized testing strategies are needed to define clinically meaningful AT1R-Ab cutoffs and clarify their utility in risk stratification and targeted therapeutic trials.

Introduction: Takotsubo cardiomyopathy (TTC) is diagnosed in 1-2% of the patients presenting with troponin positive suspected acute coronary syndromes(ACS). Rising trends of adverse events in patients with TTC, makes it imperative to explore causes and predictors of readmission in this patient population. Methods: National Readmission Data (NRD) 2013-14 was utilized to select study cohort. International Classification of Diseases, 9th Revision (ICD-9-CM) diagnostic code 429.83 was used to identify takotsubo cardiomyopathy. Admissions within 90 day of index admission were considered as early readmissions. Readmission etiologies were identified by ICD-9-CM code in primary diagnosis field of readmissions. Hierarchical multivariate models were used to evaluate predictors of early readmission. Results: A total of 12255 patients were identified during study period out of which 23.92% (n=2932 with 4224 readmissions) patients were readmitted within 90 days of discharge following index admission. Most common etiologies for readmission were cardiac (18.56%), respiratory (17.20%), GI renal (9.10%), infections (13.12%) and neurological complications (5.88%). Among cardiac complications acute heart failure was the most common etiology (7.48%). Highest number of readmissions happened on first day after discharge (n=125) and within 33 days after discharge, >50% of readmissions took place (n=2136). Conclusions: Patients with TTC are highly likely to be readmitted with first month after discharge, most likely secondary to cardiac or respiratory complications. These findings warrant close post discharge transition to reduce morbidity and improve health care outcomes.

Introduction: Heart failure with preserved ejection fraction(HFpEF) is a syndromemwith limited treatment modalities. Our control over 30 day readmissions and readmission outcomes is limited. Methods: HCUP’s Nationwide Readmissions Database (NRD) from 2013-14 was used for HFpEF related hospitalizations using ICD-9- CM diagnostic code:428.3x in primary diagnosis field. 30-day readmissions were identified and classified into two groups: same-hospital readmissions and different-hospital readmissions. A comparative analysis was conducted focused on three metrics - mortality, length of stay (LOS) and cost of hospitalization. We used hierarchical two-level modeling and propensity score matching to adjust for confounders. Results: Of the 94,988 readmitted patients (age >65 years: 79%, Females: 61.45%) - 76,665 (80.70%) to the same hospital and rest to different hospitals. After adjusting extensive list of confounders, same hospital readmission was associated with better outcomes including in hospital mortality (OR: 0.73, 95% CI: 0.66 - 0.80, p<0.001), LOS (Days: -1.14, 95% CI: -1.31 - -0.97, p<0.001), Cost of care ($: -4208, 95% CI: - 4681 - -3734, p<0.001). For validation of our results, we ran propensity score matching, showed similar results - in hospital mortality (6.23% vs 8.07%), LOS (6.30 ± 0.08 vs 7.47 ± 0.095), Cost of care (14042.7 ± 215.7 vs 18685.4 ± 279.2). Post hoc high-risk subgroup analysis were conducted and showed similar results (Figure). Number needed to treat (for mortality) was 74 patients. Up to ~ 100 million dollars could have been saved over 2 years. Conclusions: Considering scale of problem and limited option to prevent worse outcomes, Simple interventions such as redirecting patient to same hospital as previous admission would be beneficial.

Introduction: Role of therapeutic hypothermia in out of hospital cardiac arrest is well studied but data is sparse for in-hospital cardiac arrest (IHCA). Methods: Nationwide Inpatient Sample (NIS) database from 2011-2014 was utilized to identify ICHA using the ICD-9-CM procedural codes 99.60(CPR) and 99.63(closed cardiac massage) in any procedural fields. Therapeutic hypothermia was identified by 99.81 in any procedural field. Patient with age<18 years and missing information on age, gender and mortality was removed. Primary outcome was hospitalization survival. We used Greedy’s algorithm for propensity score match (1:20) to adjust for extensive list of clinically important confounders. We used simple logistic regression to generate odds ratio on matched cohort. Results: 86,593 patients (Age>65 years: 58.48%, female: 44.12%) with In hospital cardiac arrest was identified,of which 1777 (2.05 %) received therapeutic hypothermia. Overall survival was 30%- with or without hypothermia. After propensity score matching (1:20) we identified 1537 matched pairs (32,277 patients) without any statically significant difference in baseline characteristics between two groups. C- index for the model was 0.714. Worse survival was observed in patients with hypothermia in matched cohort [Survival: (31.82% without hypothermia vs. 28.1% with hypothermia with p-value- 0.002) (OR:0.84, 95% CI:0.75-0.94, p-0.002)]. About a quarter of in-hospital cardiac arrest were Vfib/Vtach arrest and Subgroup propensity score match analysis in Vfib/Vtach arrest showed better survival without hypothermia, similar results were observed in PEA/asystole cardiac arrest. Conclusion: Worst survival was observed with hypothermia in hospital cardiac arrest patients. Risk of hypothermia complications outweighs the benefit of preserving brain in patients who received almost immediate resuscitation. Future clinical trials and prospective studies will be needed to concur our results.

Introduction: Acute myocardial infarction (AMI) during pregnancy is a rare but fatal complication. Recent trends in incidence of pregnancy-related AMI and associated outcomes are unclear. Methods: Nationwide inpatient sample (NIS) database was utilized for years 2005-2014. International classification of disease-Ninth revision (ICD-9) was used to identify pregnancy-related (antepartum as well as postpartum) admissions and acute myocardial infarction (AMI). The primary outcome was incidence and trend of AMI related to pregnancy during the study period. Secondary outcomes were trends in mortality and resource utilization. P-values for trends were generated by Cochrane-Armitage test for categorical variables and simple linear regression for continuous variables. Results: We identified a total of 43,437,621 pregnancy-related hospitalization and 3,786 cases of AMI (86% antepartum and 14% post-partum) were noted during the study period. The incidence of AMI during the study period was 8.7 per 100,000 pregnancies with an overall increase in incidence during study period (relative increase of 18.9%, p <0.001) and concomitant decrease in mortality (relative decrease of 40.05%, p <0.001), cost of care (relative decrease of 8.70%, p<0.001) and length of stay (relative decrease of 13.53%, p<0.001). Conclusions: Incidence of AMI during the period is on the rise in recent years with concomitant improvement in mortality and resource utilization. This reflects improved diagnostic capability and a better understanding of non-atherosclerotic mechanisms of AMI during pregnancy such as spontaneous coronary artery dissection, coronary spasm, and coronary thrombus.

Introduction: Recent trials have suggested potential benefits of performing multivessel percutaneous coronary intervention (MVPCI) on non-infarct related artery (non-IRA) in ST-segment elevation myocardial infarction (STEMI) patients with multivessel disease. Methods: National Readmissions Database (NRD) 2010-14 was utilized to select study cohort. Appropriate International Classification of Diseases, 9th Revision (ICD-9-CM) diagnostic and procedural codes were utilized to identify STEMI patients undergoing multivessel PCI and infarct-related artery only PCI (IRA-PCI). Propensity score matched cohorts using greedy matching algorithm were generated for comparison of outcomes. Results: We identified 116592 IRA-PCI (83.97%) and 22257 MVPCI (16.03%) cases. With 1:3 propensity matched cohorts accounting for confounders such as age, gender, race and comorbidities, in comparison to IRA-PCI, MVPCI patients have higher 30-day readmission rate (10.40% vs 9.40%, p=0.001), in-hospital mortality (1.96% vs 1.57%,p<0.001), mechanical circulatory support utilization (4.27 vs 2.44%,p<0.001) as well as higher complication including vascular (0.51% vs 0.28%, p<0.001), cardiac (5.97% vs 3.97%, p<0.001), respiratory (4.89% vs 4.02%,p<0.001), neurologic complications (0.77% vs 0.58%,p=0.003), major bleeding (1.01% vs 0.79%, p=0.002) and cardiac arrest(3.48% vs 3.17%, p=0.027). We also noted higher cost of care ($27100 vs $20900, p<0.001) and length of stay (3.8 days vs 3.4 days, p<0.001) in MVPCI group compared to IRA-PCI group. Conclusions: We noted higher 30- day readmission rate, in-hospital mortality, complications and resource utilization with MVPCI compared to IRA-PCI approach among STEMI patients which further demands large-scale randomized control trials to determine the utility of MVPCI in the “real world”.

Background Atrial fibrillation is the most common arrhythmia worldwide. Data regarding 30‐day readmission rates after discharge for atrial fibrillation remain poorly reported. Methods and Results The Nationwide Readmission Database (2010–2014) was queried using the International Classification of Diseases, Ninth Revision ( ICD‐9 ) codes to identify study population. Incidence, etiologies of 30‐day readmission and predictors of 30‐day readmissions, and cost of care were analyzed. Among 1 723 378 patients who survived to discharge, 249 343 (14.4%) patients were readmitted within 30 days. Compared with the readmitted group, the nonreadmitted group had higher utilization of electrical cardioversion and catheter ablation. Atrial fibrillation was the most common cause of readmission (24.1%). Median time to 30‐day readmission was 13 days. Advancing age, female sex, and longer stay during index hospitalization predicted higher 30‐day readmissions, whereas private insurance, electrical cardioversion, catheter ablation, higher income, and elective admissions correlated with lower 30‐day readmission. Comorbidities such as heart failure, neurological disorder, chronic obstructive pulmonary disease, diabetes mellitus, chronic kidney disease, chronic liver failure, coagulopathy, anemia, peripheral vascular disease, and electrolyte disturbance, correlated with increased 30‐day readmissions and cost burden. Trend analysis showed a progressive decline in 30‐day readmission rates from 14.7% in 2010 to 14.3% in 2014 ( P trend, <0.001). Conclusions Approximately 1 in 7 patients were readmitted within 30 days of discharge, with symptomatic atrial fibrillation being the most common cause. We identified a predictive model for increased risk of readmissions and treatment expense. Electrical cardioversion during index admission was associated with a significant reduction in 30‐day readmissions and service charges. The 30‐day readmissions correlated with a substantial rise in the cost of care.

AbstractBackgroundCatheter ablation is widely accepted intervention for atrial fibrillation (AF) refractory to antiarrhythmic drugs, but limited data are available regarding contemporary trends in major complications and in‐hospital mortality due to the procedure. This study was aimed at exploring the temporal trends of in‐hospital mortality, major complications, and impact of hospital volume on frequency of AF ablation–related outcomes.MethodsThe Nationwide Inpatient Sample database was utilized to identify the AF patients treated with catheter ablation. In‐hospital death and common complications including vascular access complications, cardiac perforation and/or tamponade, pneumothorax, stroke, and transient ischemic attack, were identified using International Classification of Disease (ICD‐9‐CM) codes.ResultIn‐hospital mortality rate of 0.15% and overall complication rate of 5.46% were noted among AF ablation recipients (n = 50,969). Significant increase in complications during study period (relative increase 56.37%, P‐trend < 0.001) was observed. Cardiac (2.65%), vascular (1.33%), and neurological (1.05%) complications were most common. On multivariate analysis (odds ratio [OR]; 95% confidence interval [95% CI]; P value), significant predictors of complications were female sex (OR = 1.40; CI = 1.17–1.68; P value < 0.001), high burden of comorbidity as indicated by Charlson Comorbidity Index ≥2 (OR = 2.84; CI = 2.29–3.52; P value < 0.001), and low hospital volume (< 50 procedures).ConclusionOur study noted a decline in AF ablation–related hospitalizations and complications associated with the procedure. These findings largely reflect shifting trends of outpatient performance of the procedure and increasing safety profile due to improved institutional expertise and catheter techniques.

AbstractBackgroundUnderstanding the factors associated with early readmissions following atrial flutter (AFL) ablation is critical to reduce the cost and improving the quality of life in AFL patients.MethodThe study cohort was derived from the national readmission database 2013–2014. International Classification of Diseases, 9th Revision (ICD‐9‐CM) diagnosis code 427.32 and procedure code 37.34 were used to identify AFL and catheter ablation, respectively. The primary and secondary outcomes were 90‐day readmission and complications including in‐hospital mortality. Cox proportional regression and hierarchical logistic regression were used to generate the predictors of primary and secondary outcomes respectively. Readmission causes were identified by ICD‐9‐CM code in primary diagnosis field of readmissions.ResultReadmission rate of 18.19% (n = 1,010 with 1,396 readmissions) was noted among AFL patients (n = 5552). Common etiologies for readmission were heart failure (12.23%), atrial fibrillation (11.13%), atrial flutter (8.93%), respiratory complications (9.42%), infections (7.4%), bleeding (7.39%, including GI bleed–4.09% and intracranial bleed–0.79%) and stroke/TIA (1.89%). Multivariate predictors of 90‐day readmission (hazard ratio, 95% confidence interval, P value) were preexisting heart failure (1.30, 1.13–1.49, P < 0.001), chronic pulmonary disease (1.37, 1.18–1.58, P < 0.001), anemia (1.23, 1.02–1.49, P = 0.035), malignancy (1.87, 1.40–2.49, P < 0.001), weekend admission compared to weekday admission (1.23, 1.02–1.47, P = 0.029), and length of stay (LOS) ≥5 days (1.39, 1.16–1.65, P < 0.001). Note that 50% of readmissions happened within 30 days of discharge.ConclusionCardiac etiologies remain the most common reason for the readmission after AFL ablation. Identifying high risk patients, careful discharge planning, and close follow‐up postdischarge can potentially reduce readmission rates in AFL ablation patients.

AbstractCardiac allograft rejection and failure may require mechanical circulatory support as bridge‐to‐retransplantation. Prognosis in this patient group is poor and implantable ventricular assist devices have had limited success due to organ failure associated with the high dose immunosuppression required to treat ongoing rejection. We present a case from our institution and the world‐wide experience utilizing the SynCardia CardioWest Total Artificial Heart (TAH‐t; SynCardia Systems, Inc., Tucson, AZ, USA) for replacement of the failing graft, recovery of patient and end‐organ failure with ultimate bridge to retransplantation. We present our experience and review of world‐wide experience for use of TAH‐t in this type patient.