Non Compaction Cardiomyopathy (NCCM), an Underdiagnosed Disorder?

Aim: To describe uncommon clinical presentations of NCCM patients

Background: Left ventricular NCCM or ‘’spongy myocardium’’ is a rare cardiomyopathy, with a reported prevalence of 0.014%-1.2%. The entity has some typical complications, the triad of heart failure, ventricular arrhythmias and embolic events. Echocardiography is the standard diagnostic tool and MRI can confirm or rule it out when the apex is difficult to visualise. Mortality rates are similar to those found in non-ischemic dilated cardiomyopathy.

Subjects & Methods: During the period 1.1.2015 -1.10.2015, 5 patients, 4 males & 1 female, age range - 16-50 years who had all accepted echocardiographic diagnostic criteria were included, i.e. the presence of at least 4 prominent trabeculations, and deep intertrabecular recesses, blood flow from the ventricular cavity into the intertrabecular recesses, and a typical bilaminar structure of the affected portion of left ventricular myocardium, ratio of noncompacted/compacted myocardium greater than 2.3 in diastole, and a trabeculated left ventricular mass above 20% of total mass.

Results: 3 patients were diagnosed in the outpatient clinic (during investigation for a thromboembolic source, a cardiac murmur, and asymptomatic bradycardia) and two were diagnosed upon admission to CCU with acute heart failure. Typical echocardiographic findings where shown in all patients, while MRI was done in only 1 patient, confirming the diagnosis. Their past history was uneventful without any arrhythmia, supraventricular or ventricular, and similarly among their first grade relatives no case of sudden cardiac death or significant cardiac morbidity was found. ECG showed left ventricular hypertrophy in 4 patients, and conduction disturbances in none.

Conclusion: NCCM should be considered as a possible diagnosis even in the absence of the typical clinical triad because of its potential for severe complications, thus, we believe that NCCM is an underdiagnosed disorder. Genetic consulting and evaluation that includes family members is probably recommended.