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.