Introduction:
Isolated LVNC is characterized by prominent LV trabeculae and deep intertrabecular recesses which are filled with blood from the ventricular cavity without evidence of communication to the epicardial coronary artery system. Additionally, a thin compacted layer of myocardium is present. It has been cataloged as an unclassified cardiomyopathy by the European Society of Cardiology (ESC), while the American Heart Association (AHA) classifies it as a genetic cardiomyopathy 1-2. About its pathogenesis, a congenital and an acquired basis have been proposed. The former, states that during the embryological heart development process the myocardial compaction is disrupted through unknow mechanisms; and the latter that LVNC could be acquired and developed on time 3. Besides, trabeculations that could fulfill criteria for LVNC have been described in athletes, pregnancy and patients with chronically increased LV pre-load and afterload diseases like heart valve disease, chronic renal failure and sickle cell disease 3.
Nevertheless, a family history has been described in a significant proportion of patients with an autosomal dominant X-linked transmission4. Furthermore, several gene mutations have been reported primarily in genes coding for sarcomeric, cytoskeletal, Z-line and mitochondrial proteins 4. The first mutation described was in the tafazzin gene, although others like MYH7, RYR2 and lamin A/C have been reported. These findings suggest that also genetics is involved in LVNC development 4. Consequently, current research evidence points towards to its reclassification as a distinct phenotype resulting from the interaction between the environment and genetics 5.
LVNC prevalence in general population is not known, but it has been described between 0.014 and 1.3 % in patients undergoing echocardiography 6-8. Even though it has been reported in some cases, the right ventricular non compaction (RVNC) real prevalence is unknow maybe due to its unclear definition and recognition3. Nowadays, there is no gold standard for LVNC diagnosis, however echocardiography and cardiac magnetic resonance (CMR) are the best diagnostic tests currently available3.
Clinical manifestations of the LVNC cardiomyopathy are multiple and non-specific, including dyspnea, chest pain, palpitations and syncope. Furthermore, non-sustained ventricular tachycardia (VT), left bundle branch block (LBBB) and atrial fibrillation (AF) have been described as the most frequent electrocardiographic findings 8-11. Herein, we describe a case of frequent PVCs as first manifestation of a patient with LVNC cardiomyopathy.