Research Output of Adult Cardiothoracic Anesthesiology Fellowship Matriculants: A National Cross-Sectional Analysis

Background Adult cardiothoracic anesthesiology (ACTA) is a highly specialized and increasingly competitive subspecialty within anesthesiology. As research engagement becomes a more prominent component of both residency and fellowship training, scholarly productivity is commonly considered as one of several factors in fellowship selection. However, to our knowledge, no prior national study has evaluated the research output and bibliometric impact of applicants who successfully matched into ACTA fellowships in the United States. Methods We conducted a cross-sectional study of ACTA fellows matriculating in the 2024-2025 academic year across programs accredited by the Accreditation Council for Graduate Medical Education (ACGME). Data were obtained from program websites, Doximity (Doximity, Inc., CA, USA), and PubMed/Scopus. Demographic variables included gender, medical degree, and regions of residency and fellowship training. The primary outcome was the total number of peer-reviewed publications per fellow prior to fellowship matriculation. Secondary outcomes included first-author publication count, Scopus h-index, mean Journal Citation Reports (JCR) impact factor of journals published in, and weighted JCR impact factor. Statistical comparisons were made using t-tests and analysis of variance (ANOVA) with post-hoc testing. Results Data were available for 211 fellows across 62 programs (80.5% of all positions). Most fellows were male (66.8%) and held M.D. degrees (79.6%). Publication data were found for 201 fellows, of whom 125 (62.2%) had at least one publication. Across the entire cohort, the mean number of total publications was 2.45 ± 4.8 (median = 1), first-author publications was 0.69 ± 2.1 (median = 0), and h-index was 1.53 ± 2.3 (median = 1). Among published fellows, the mean h-index increased to 2.46 ± 2.5, the mean JCR impact factor to 5.23 ± 9.0, and the mean weighted JCR impact factor to 23.4 ± 47.5. No significant gender-based differences were observed in publication counts, h-index, or impact factor metrics. M.D. graduates demonstrated significantly higher total and first-author publications, h-indices, and impact factor values than D.O. graduates (all p < 0.01). Fellows who completed international residency training exhibited the highest overall research productivity, with more total and first-author publications than U.S.-trained peers (all p < 0.05). By fellowship region, fellows training in the West had significantly higher h-indexes, mean JCR impact factors, and weighted impact factors compared with those in other regions (all p < 0.05). Conclusions To our knowledge, this is the first national study to quantify both pre-fellowship research productivity and the bibliometric impact of ACTA fellows. While most fellows had modest pre-fellowship publication counts, degree type and training region were significantly associated with scholarly productivity and journal impact metrics. These findings suggest that while research experience may enhance competitiveness, it is not universally required for ACTA fellowship selection. Increased support for research engagement across training environments may help promote equity and academic development within the field.