BACKGROUND: Isolated left ventricular noncompaction (ILVNC) is a cardiomyopathy 
caused by intrauterine failure of the myocardium to compact. Common clinical 
complications are heart failure, arrhythmias, and cardioembolism. A paucity of 
data exists relating to clinical and echocardiographic features of ILVNC in 
Africans.
METHODS AND RESULTS: This study is a single-center, prospective case-control 
study, whereby subjects attending a dedicated cardiomyopathy clinic were 
screened for and diagnosed with ILVNC, provided they had no other associated 
structural heart disease and fulfilled all the accompanying echocardiographic 
criteria: (1) end-systolic ratio of noncompacted layer to compacted layer >2, 
(2) presence of >3 prominent apical trabeculations, and (3) deep intertrabecular 
recesses that fill with blood from the ventricular cavity visualized using color 
Doppler ultrasound. Fifty-four subjects were identified, age 45.4±13.1 years 
(mean±SD), 95% confidence interval 3.6 to 10.2, 55.6% male, and 63.0% New York 
Health Association Class II, and prevalence of LVNC in our clinic was 6.9%, 95% 
confidence interval 3.6 to 10.2. Heart failure because of systolic dysfunction 
was the most common clinical presentation (53 subjects, 98.1%). Left ventricular 
end-diastolic diameter was 61.4±7.2 mm (mean±SD) and ejection fraction 
26.7±11.9% (mean±SD). Common sites of noncompaction were the apical (100%), 
midinferior (74.1%), and midlateral (64.8%) walls. Right ventricular 
noncompaction occurred in 12 subjects (22.2%). Pulmonary hypertension was 
documented in 45 cases (83.3%). Right ventricular dilation was noted in 40 
subjects (74.1%), while right ventricular function was depressed in 32 (59.3%). 
Tricuspid S' was 9.6±2.8 cm/s (mean±SD). No echocardiographic features 
suggestive of ILVNC were noted in a healthy control group of African descent.
CONCLUSIONS: ILVNC in patients of African descent can be characterized by 
biventricular abnormality and pulmonary hypertension, in addition to isolated 
left-sided abnormality.