Prevalence of Persistent Left Superior Vena Cava in Patients with Congenital Heart Disease: A Systematic Review with Meta-Analysis.

Persistent left superior vena cava (PLSVC) is the most frequently reported anatomical variant of the thoracic systemic venous system. While its association with congenital heart disease (CHD) is well recognized, its prevalence within CHD populations and its relative occurrence compared with non-CHD cohorts remain incompletely characterized. This study aimed to estimate the pooled prevalence of PLSVC among patients with CHD and to assess its relative frequency compared with that in control populations. A systematic review of PubMed, Scopus, and Web of Science was conducted from database inception to January 2026. Studies reporting the prevalence of PLSVC in CHD cohorts were included. A random-effects meta-analysis was performed, and risk ratios (RRs) were calculated for studies that included both CHD and non-CHD groups. Sixteen studies (n = 37,370) were included. The pooled prevalence of PLSVC in CHD patients was 6.36% (95% CI: 4.70-8.24). Significant heterogeneity was identified (I2 = 97.6%). An increased likelihood of PLSVC was observed in CHD populations (RR = 15.34; 95% CI: 5.72-41.14). However, this relative risk is based on a highly limited number of comparative studies (n = 4) and exhibits substantial heterogeneity (I2 = 92.47%); thus, it must be interpreted with significant caution. Subgroup analyses did not demonstrate statistically significant differences based on nationality (p = 0.59), study type (p = 0.32) and age group (p = 0.95), while imaging modality was statistically significant (p = 0.01). PLSVC is observed in a notable proportion of patients with CHD, although variability in reported prevalence is substantial and likely influenced by methodological differences across studies. Given its potential implications for catheter-based and surgical procedures, systematic evaluation of thoracic venous anatomy should be considered during the diagnostic and preoperative assessment of patients with CHD.