Comparison of atrial fibrillation prevalence and in-hospital cardiovascular outcomes between patients undergoing allogeneic versus autologous hematopoietic stem cell transplantation: insights from the national inpatient sample.

Hematopoietic stem cell transplantation (HSCT) is a potentially curative therapy for several malignant and non-malignant hematologic conditions. However, patients undergoing HSCT are at increased risk of developing serious cardiovascular events. Whether cardiovascular risks differ by the type of transplantation strategy used, allogeneic versus autologous HSCT, is unknown. Leveraging the National Inpatient Sample (2016-2019), we assessed the incidence of early cardiovascular events by HSCT mode (allogeneic vs autologous). The primary outcome was the incidence of atrial fibrillation (AF). The secondary outcome was the occurrence of any major adverse cardiac events (MACE), defined as acute heart failure, myocardial infarction (MI), symptomatic atrial or ventricular arrhythmia or heart block, and cardiovascular death. Outcomes were compared between those undergoing allogeneic versus autologous HSCT. Multivariable regression, adjusting for cardiovascular and cancer-related factors, was used to define the association between pre-HSCT factors and MACE. We further assessed the effect of acute cardiovascular events on in-patient mortality by calculating adjusted odds ratio (aOR) with corresponding 95% confidence intervals (CI) and p-values. Overall, 64,705 weighted hospitalizations for HSCT were identified, of which 22,655 (35.0%) were allogeneic HSCT and 42,050 (65.0%) were autologous HSCT. The prevalence of AF was 9.1%, and 12.1% for any arrhythmia. In multivariable regression, allogeneic HSCT was associated with higher adjusted odds of peri-HSCT acute heart failure (aOR 2.64; 1.86-3.76; p < 0.0001), QT prolongation (aOR 1.40; 1.04-1.88; p = 0.025), MI (aOR 2.87; 1.16-7.11; p = 0.023), any major cardiovascular complication (aOR 1.16; 1.03-1.32; p = 0.016), and inpatient mortality (aOR 4.87; 3.60-6.58; p < 0.0001). Following cerebrovascular events, AF was the strongest predictor of mortality. Allogeneic HSCT was associated with higher odds of in-hospital cardiovascular complications among patients undergoing HSCT.