A systematic review and meta-analysis of the prevalence of left ventricular non-compaction in adults.

Aims To assess the reported prevalence of left ventricular non-compaction (LVNC) in different adult cohorts, taking in to consideration the role of diagnostic criteria and imaging modalities used. Methods and results A systematic review and meta-analysis of studies reporting LVNC prevalence in adults. Studies were sourced from Pre-Medline, Medline, and Embase and assessed for eligibility according to inclusion criteria. Eligible studies provided a prevalence of LVNC in adult populations (>= 12 years). Studies were assessed, and data extracted by two independent reviewers. Fifty-nine eligible studies documenting LVNC in 67 unique cohorts were included. The majority of studies were assessed as moderate or high risk of bias. The pooled prevalence estimates for LVNC were consistently higher amongst cohorts diagnosed on cardiac magnetic resonance (CMR) imaging (14.79%, n = 26; I-2 = 99.45%) compared with echocardiogram (1.28%, n = 36; I-2 = 98.17%). This finding was unchanged when analysis was restricted to studies at low or moderate risk of bias. The prevalence of LVNC varied between disease and population representative cohorts. Athletic cohorts demonstrated high pooled prevalence estimates on echocardiogram (3.16%, n= 5; I-2 = 97.37%) and CMR imaging (27.29%, n = 2). Conclusion Left ventricular non-compaction in adult populations is a poorly defined entity which likely encompasses both physiological adaptation and pathological disease. There is a higher prevalence with the introduction of newer imaging technologies, specifically CMR imaging, which identify LVNC changes more readily. The clinical significance of these findings remains unclear; however, there is significant potential for overdiagnosis, overtreatment, and unnecessary follow-up.