Cardiac Magnetic Resonance Features and Outcomes of Patients With Non-Compaction Cardiomyopathy - a Retrospective Follow-up From Pakistan

Left Ventricle Non-Compaction Cardiomyopathy (LVNCC) is a type of myocardial disease characterized by prominent myocardial trabeculae and recesses resulting in two distinct layers of myocardium: compacted layer and the non-compacted layer. It arises due to the failure of left ventricle (LV) maturation and compaction during intra-uterine life (1). As per the position statement from the European Society of Cardiology, LVNCC has been labelled as 'unclassified' type of cardiomyopathy. Clinical course can be complicated by heart failure, thromboembolism, or arrhythmia.

Phenotypic presentation of LVNC can range from extremely thickened layer of non-compacted myocardium to mere presence of prominent trabeculae and recesses albeit a compacted myocardium. Transthoracic echocardiography is the first tool to diagnose LVNC. However, Cardiac Magnetic Resonance (CMR) imaging has emerged as a strong tool to differentiate between LVNCC from mere hyper-trabeculated LV myocardium when echocardiogram is inconclusive (Figure 1 and Video 1). Various criteria have evolved to diagnose LVNC by CMR. Peterson et al defined the end-diastole non-compacted to compacted myocardium ratio of >2.3 to have good sensitivity, specificity, and negative predictive value for differentiating pathological non-compaction from hyper-trabeculation.

With an increase in the use of diagnostic cardiovascular imaging modalities in South-Asian (SA) belt, LVNC is being increasingly diagnosed. The exact prevalence of LVNC in SA is not known and phenotypic CMR characteristics, clinical features, and outcomes of LVNC remain unknown for SA population. This brought us to the need of analysing CMR data of LVNC at our centre.