Supplementary Material for: National Trends and Procedural Complications from Endomyocardial Biopsy: Results from the National Inpatient Sample, 2007–2014

<b><i>Aim:</i></b> The aim of this study is to report recent trends in the performance of endomyocardial biopsy (EMB) and its in-hospital complications (and their predictors) in the United States (US). <b><i>Method:</i></b> We analyzed Nationwide Inpatient Sample (NIS) database from years 2007 through 2014 to identify patients who underwent EMB. Once identified, the patients were subdivided into those with no history of heart transplant (HT) (cohort 1) and those with history of HT (cohort 2). We then studied the major complication of pericardial effusion, hemopericardium or/and cardiac tamponade that required a pericardiocentesis or a pericardial window (CTRPD) following the EMB procedure. <b><i>Results:</i></b> We observed a steady increase in the in-patient EMB procedures, with more EMB procedures being performed in males and in Caucasians. In cohort 1, the CTRPD was higher (0.70%) as compared to cohort 2 (0.19; <i>p</i> = 0.01). CTRPD in women was higher compared to men (0.94 vs. 0.53% <i>p</i> = 0.022). Most of the EMB procedures are performed in teaching hospitals. The CTRPD rate was significantly higher in the nonteaching hospitals when compared to teaching hospitals in both cohort 1 and cohort 2 (3.4 vs. 0.53% and 1 vs.0.18%, respectively; <i>p</i> = 0.01 and < 0.001, respectively). The overall mortality in cohort 1 was 4.3% as compared to 2.5% in cohort 2; <i>p</i> = 0.01. In cohort 1, the mortality was significantly higher in the group that had EMB-related complications versus the group without the complications (20 vs. 2.5%; <i>p</i> < 0.001). <b><i>Conclusion:</i></b> There has been an increase in the number of EMB procedures in the US in recent years. Though the overall risk of CTRPD is very low, the risk is significantly higher in cohort 1, women, and in nonteaching hospitals. The study results provide data benchmarks for assessing EMB outcomes in the US.