Risk of delayed diagnosis in young patients with left ventricular non-compaction - a potential benefit of magnetic resonance imaging.

BACKGROUND: Left ventricular non-compaction (LVNC) is a rare form of cardiomyopathy resulting from a disorder of endomyocardial morphogenesis associated with significantly increased risk of cardiovascular morbidity and premature mortality. Despite the widespread use of echocardiography, LVNC is commonly overlooked, often due to lack of knowledge about this disorder. METHODS AND RESULTS: A complex diagnostic process and follow-up was analysed in 24 patients diagnosed with LVNC between March 2002 and February 2016 (16 boys, 8 girls; age at presentation 9 days - 18 years; follow-up 2-7 years). 17 patients were initially overlooked and followed-up for different diagnoses. After retrospective evaluation by a senior specialist in paediatric cardiology, LVNC was identified in 3 patients initially diagnosed with dilated cardiomyopathy, 11 patients followed-up with various forms of arrhythmias, and 3 patients with congenital heart disease. The diagnosis of LVNC was confirmed using magnetic resonance imaging in all patients. The classical triad of complications - heart failure, ventricular arrhythmias and systemic embolic events - was not confirmed in this study, electrocardiographic findings were abnormal in 87.5% of patients. Isolated non-compaction of the left ventricular myocardium was a dominant form of non-compaction. CONCLUSIONS: The high variability of morphological findings and clinical manifestations of LVNC results in frequent overlooking of this disorder. Therefore, it is important to make the specialists more familiar with this condition and its pathology. Magnetic resonance imaging represents a conducive method to make correct diagnosis of LVNC under several specific conditions, particularly in case of non-conclusive echocardiographic finding.