CARDIOVASCULAR JOURNAL OF AFRICA • Vol 22, No 2, March/April 2011
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AFRICA
useful to demarcate endocardial borders and visualise intra-
trabecular recesses. Other diagnostic modalities that may aid
diagnosis are MRI and invasive left ventricular angiography.
The clinical presentation revolves around three key features,
namely heart failure, arrhythmias and left ventricular thrombus
formation. It is important to note that the clinical manifestation
and age of presentation are variable.
1,2
Heart failure is commonly
the basis of systolic dysfunction, which may be related to micro-
vascular ischaemia and very uncommonly patients may have
only diastolic dysfunction.
7
Arrhythmias, particularly ventricular tachyarrhythmias are
a cause of sudden death and may mandate the implantation of
an ICD as primary prevention in patients with severe systolic
dysfunction. Thrombus formation occurs because of stasis
within the trabeculae and cardio-embolism can occur in particu-
lar in the cerebral, coronary and mesenteric circulation. Hence
oral anticoagulation with adequate INR monitoring is essential
and is suggested even in the absence of documented thrombus
formation.
Other clinical associations include facial dysmorphisms and
neuromuscular abnormalities. In one series, familial disease was
found in up to 44% of cases. Klaasen
et al
. have subsequently
described various sarcomeric mutations that may be found in
isolated left ventricular non-compaction.
8
This particular clinical case highlights the importance of
paying attention to the heart apex on echocardiography, since
under normal circumstances this is the thinnest portion of the
ventricle. The presence of blood flow within the trabecular
recesses differentiates the findings of non-compaction from
apical hypertrophic cardiomyopathy, cardiac tumours and throm-
bus formation. Furthermore, it is very uncommon to find more
than four trabeculae in a normal left ventricle.
9
The spectrum of
non-compaction with normal ejection fraction by conventional
echo indices is uncommon and was the first case noted in our
clinic.
Isolated LV non-compaction with normal ejection
fraction
A review of the literature reveals that in the first case series
described by Chin
et al
. in 1990, 63% of patients had depressed
LV systolic function.
2
A recent analysis of the Mayo Clinic echo
database 2001–2006 revealed that 77% of the 30 patients who
fulfilled the criteria for isolated left ventricular non-compaction
had a low ejection fraction.
10
In one of the largest series that included 78 patients with
isolated LV non-compaction diagnosed by the Jenni criteria,
Steffel
et al
. identified an ejection fraction greater than 50%
on left ventricular cine angiography in 32% of their patients.
11
Furthermore, in children, isolated LV non-compaction may
present initially as a restrictive cardiomyopathy.
12
Therefore it is clear that isolated LV non-compaction can
be found in patients with normal ejection fraction. Whether
these patients progress to overt systolic dysfunction is not well
described in the current literature but this may be possible as part
of a spectrum related to chronic microvascular ischaemia with
secondary fibrosis and remodelling.
The prognosis of patients with non-compaction is variable,
although the literature suggests a poor survival, with one large
series having only 60% of patients at six years who had not died
or undergone cardiac transplantation.
3,13,14
The Mayo group have
suggested from an analysis of their database that the morbidity
and mortality of patients with isolated LV non-compaction may
be related to the presence of left ventricular dysfunction and not
the non-compacted myocardium.
10
Furthermore, although their
follow up was only 2.5 years, no deaths were observed in the
subgroup with normal ejection fraction, suggesting that ICD
therapy may be reserved for patients who have left ventricular
dysfunction.
Therefore it seems that the measurement of ejection fraction
is a powerful marker of overt systolic dysfunction and is associ-
ated with a poorer prognosis in these patients. It is clear that a
normal ejection fraction does not imply normal systolic function
and techniques such as tissue Doppler imaging or speckle track-
ing may be able to detect abnormal systolic myocardial mechan-
ics when the ejection fraction is normal. These abnormalities can
be demonstrated in conditions such as amyloid and hypertrophic
cardiomyopathy where ejection fraction can be normal despite
overt regional systolic dysfunction.
In amyloid cardiomyopathy there is profound depression of
longitudinal systolic strain despite a normal ejection fraction.
However, regional analysis of myocardial mechanics or sub-
analysis of systolic myocardial mechanics such as longitudinal
strain or torsion has not been well documented in this condition.
A recent report by Punn
et al
. in children utilised speckle track-
ing to demonstrate that that differences in contractility existed
between areas that were normal compared to areas that displayed
features of non-compaction.
15
They also found that greater
numbers of affected segments correlated linearly and inversely
with ejection fraction.
Conclusion
The optimal management of our patient besides the use of warfa-
rin is unclear and the arrhythmic risk in this subgroup that has
normal ejection fraction is probably not as sinister as it is for
patients with left ventricular dysfunction. However, patients who
have diastolic dysfunction are at increased risk for atrial fibrilla-
tion, which, according to a recent report, seems to alter survival.
16
This case report highlights the entity of isolated LV non-
compaction with normal ejection fraction and emphasises some
important issues that need to be explored in a more scien-
tific manner so that the practicing clinician can better manage
patients diagnosed with this condition.
References
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et
al
. Contemporary definitions and classification of the cardiomyopathies:
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Quality of Care and Outcomes Research and Functional Genomics and
Translational Biology Interdisciplinary Working Groups; and Council
on Epidemiology and Prevention.
Circulation
2006;
113
: 1807–1816.
2. Chin TK, Perloff JK, Williams RG, Jue K, Mohrmann R. Isolated
noncompaction of left ventricular myocardium. A study of eight cases.
Circulation
1990;
82
: 507–513.
3. Ritter M, Oechslin E, Sutsch G, Attenhofer C, Schneider J, Jenni R.
Isolated noncompaction of the myocardium in adults.
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1997;
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: 26–31.
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J Am Soc
