136 Long Term Clinical Outcomes in CMR Quantified Left Ventricular Noncompaction

Abstract

There is currently no diagnostic gold standard for Left Ventricular Noncompaction cardiomyopathy (LVNC) and no definitive method to accurately delineate noncompacted myocardium. We developed a novel tool based on signal intensity to quantify noncompacted myocardial mass in 97 patients with isolated Petersen criteria LVNC and assess the association with major adverse cardiovascular and cerebrovascular events (MACCE) including cardiac death, cardiac transplantation, cardiac re-synchronization device, ventricular tachycardia and ischemic stroke. 81(83.5%) patients had preserved and 16 (16.5%) had reduced LV systolic function. In addition, five (5.2%) patients had late gadolinium enhancement (LGE); all patients had reduced LV function. Patients with reduced function had more end-systolic noncompacted mass (61.9g+/-22.4 vs 38.1g+/-15.8, p<0.001) and larger end-systolic noncompacted to total myocardial mass (44%+/-9 vs 36%+/-12, p=0.003). MACCE occurred in 12(12.3%) patients; 10(10.3%) with impaired LV function and 2(2.5%) with preserved LV function; p<0.001. Cardiac death only occurred in patients with reduced function (3/16; 18.8% and LGE (2/5; 40%); p=0.038 and 0.063. Signal intensity can accurately define noncompacted myocardium and quantify myocardial mass. In patients with isolated Petersen criteria LVNC, reduced LV function and LGE were predictors of MACCE (p<0.001) but the amount of noncompaction was not. Moving forward, future diagnostic criteria cannot be limited to the presence of noncompaction and must include LV parameters.