Incidental extracardiac findings on cardiac MR: Systematic review and meta-analysis

Abstract

Purpose: To perform a systematic review and meta-analysis to calculate the pooled prevalence of incidental extracardiac findings (IEFs) on cardiac magnetic resonance (MR) and to determine factors influencing reported prevalences.

Materials and methods: We examined studies published in the literature using the MEDLINE database. Studies reporting IEFs on cardiac MR were included. Meta-analysis provided pooled prevalences of total, minor, major IEFs, and major IEFs with patient management changes using a random-effects model. Heterogeneity and inconsistency (I-squared) between studies as well as publication bias were assessed.

Results: Twelve studies including 7062 patients (mean age: 52 years, range: 0.5-93 years, 4476 male/2586 female) and 7122 cardiac MR examinations were considered in the meta-analysis. Overall, the pooled prevalence of total IEFs was 35% (95% confidence interval [CI]: 23-47%). The pooled prevalence of minor and major IEFs were 17% (95% CI: 9-26%) and 12% (95% CI: 7-18%), respectively. Newly diagnosed major IEFs changed patient management in 1% (95% CI: 1-2%) of the study population. A high heterogeneity and inconsistency (I-squared >74%) between studies without publication bias were observed, notably due to IEFs recording method (P < 0.002) and formal training of cardiac MR readers (P < 0.006).

Conclusion: Major IEFs may be found in 12% of patients undergoing cardiac MR examination and change the management in 1% of patients. Readers' training for the evaluation of noncardiac structures increases reported prevalence.

Keywords: cardiac imaging; incidental findings; magnetic resonance imaging; meta-analysis.