BACKGROUND: Isolated ventricular non-compaction (IVNC) is a rare disorder 
characterized by prominent trabecular meshwork and deep recesses. We 
retrospectively assessed the clinical characteristics and natural course of IVNC 
in adults diagnosed at our hospital.
METHODS AND RESULTS: Sixty-seven adult patients (44 male, mean age 41 +/- 18 
years) with the diagnosis of IVNC were evaluated in this retrospective cohort. 
Its prevalence was found to be .14%. Forty-seven patients (70%) had class I/II 
functional capacity. Fifty-seven patients (85%) had electrocardiographic 
abnormalities, and the most common one was left ventricular (LV) hypertrophy 
(25%). LV systolic function was depressed in 44 patients (66%), with a median 
ejection fraction (EF) of 35% (range: 20%-48%) at diagnosis. Multiple regression 
analysis revealed that age at initial presentation, the total number of affected 
segments, and the ratio of non-compaction/compaction (NC/C) were the independent 
predictors of LV systolic dysfunction. Familial occurrence of IVNC was 33%. 
During a mean follow-up of 30 months (range: 9-50 months), major complications 
including ventricular tachycardia, heart failure requiring hospitalization, and 
cerebrovascular events were observed in 36%, 34%, and 9% of the patients, 
respectively. Ten patients (15%) with IVNC died in this study. LVEF at initial 
presentation and functional capacity at last visit were found to be independent 
predictors of mortality.
CONCLUSION: This study suggests that IVNC is a form of cardiomyopathy with 
higher prevalence and relatively better prognosis than previously reported. Age 
at initial presentation, ratio of NC/C, and number of affected segments seem to 
be major determinants of LV systolic dysfunction, while initial LVEF and last 
functional capacity predict mortality in this cohort.