CARDIOVASCULAR JOURNAL OF AFRICA • Volume 25, No 1, January/February 2014
e6
AFRICA
Discussion
Left ventricular non-compaction (LVNC) is a myocardial disease
with a genetic basis that may result in heart failure, arrhythmia,
thromboembolism and sudden death. The diagnosis based on the
ratio of the compacted to non-compacted ventricle at end-systole
was defined by Jenni
et al
.
2
and is confirmed with a ratio of
non-compacted:compacted
≥
2 in adults or
≥
1.4 in children. We
used the defined criteria for our patient. Paterick
et al
.
3
suggested
the ratio at end-diastole is also diagnostic but we did not use it
for our case.
Perhaps more so than any other cardiomyopathy, LVNC has
been misdiagnosed as distal heterotrophic cardiomyopathy,
dilated cardioyopathy or left ventricular apical thrombus.
4
It was only with the advent of superior echocardiographic
technology that discrimination of the two separate layers within
the myocardium became possible.
Malignant ventricular arrhythmias and sudden cardiac death
are the leading causes of death in left ventricular non-compaction,
5
whereas right ventricular outflow tract tachycardia is a relatively
benign clinical entity and can be cured by medical therapy and
radiofrequency ablation. Ventricular arrhythmias secondary to
left ventricular non-compaction are usually resistant to anti-
arrhythmic drug therapy.
6-8
The role of radiofrequency ablation in left ventricular
non-compaction-related ventricular tachycardia has not been
well defined and data in the literature are confined to case
reports only.
6-8
In two cases, the origin of ventricular tachycardia
was the epicardial site of the non-compacted segment of the left
ventricle, and in one case it was the interventricular septum. All
cases had sustained ventricular tachycardia that was refractory
to drug therapy.
In our case the patient was free of symptoms. On
electrophysiological study, the earliest ventricular activation site
was sought by conventional techniques. In our laboratory we
do this by simultaneously placing two ablation catheters on the
Fig. 1.
Twelve-lead electrocardiogram revealed repetitive monomorphic ventricular ectopy with the morphology of left bundle
brunch block and inferiorly directed QRS axis.
Fig. 2.
Cardiac magnetic resonance imaging revealed promi-
nent trabeculations and deep inter-trabecular recess-
es in the left ventricular chamber long-axis view. LV:
left ventricle RV: right ventricle.
