Noncompaction of the left ventricle: a new cardiomyopathy is presented to the clinician

Abstract

Noncompaction of the left ventricular myocardium is a morphogenetic abnormality involving loss of compaction of the myocardial fiber meshwork during intrauterine life. It is an extremely rare condition, accounting for only 0.05% of the cases evaluated in databanks. It has been described in both genders, in many ethnic groups and at different ages. Recently published studies of case series have shown a high mortality rate among these patients during follow-up of up to 48 months. Many cases have so far been misdiagnosed due to poor knowledge of the findings relating to this syndrome. There needs to be an attempt at early and accurate diagnosis, because of the need to investigate the patients family upon such diagnosis, and today this can be achieved using echocardiographic criteria.

Figure 1. A 12-lead electrocardiogram of a 58-year-old female patient who presented to our institution (Hospital São Francisco, Porto Alegre) with a history of dyspnea during moderate effort, with asthenia and fatigue, accompanied by palpitations, showing a left bundle branch block and a first-degree block.

Figure 2. Four-chamber image of the same patient as in Figure 1, showing prominent apical left ventricular trabeculation (white arrow), for whom a diagnosis of noncompaction was suggested. The patient had previously been given an echocardiographic diagnosis of endomyocardial fibrosis.

Figure 3. Apical four-chamber view using color Doppler, demonstrating the flow between the prominent trabeculae. This image was obtained from the same patient as in Figures 1 and 2.

Figure 4. Four-chamber image of the same patient as in Figures 1, 2 and 3, showing the X-to-Y ratio, where X is the distance between the epicardial surface and the recess through and Y refers to the distance between the epicardial surface and the trabecular apex.