The two familiar faces of thick hearts: hypertrophic
cardiomyopathy (HCM) and cardiac amyloidosis (CA).
The two most recent triumphs of modern medicine have been the emergence
of medical management of HCM and CA. In both the cases, therefore,
accurate echocardiographic diagnosis is extremely important and strain
imaging is mandatory, particularly for phenotyping differentiation of
thick hearts. In HCM, all the three morphological distributions
(sigmoid, reverse curve, apical) have distinct strain patterns, while in
CA the demonstration of classic apical sparing of left ventricular
longitudinal strain ( “cherry on the top”, one of the “red flags”)
always necessitates referral for further investigation to confirm CA (by
hematologic, scintigraphic, genetic, histologic)11.While apical strain is generally spared in
CA, different regions within the apex may exhibit subtle variations in
their response to pressure overload, as illustrated by differing
pressure strain loops obtained by myocardial work. These
variations highlight the regional differences in how these areas respond
to demand of the poorly functioning heart (Figures 4,5). In case of
hypertrophic cardiomyopathy, in which there clearly exists a gradient of
strain within the Bull’s eye plot differentiating HCM from CA,
myocardial work indices may also uncover how a poorly functioning left
ventricle distorting the pressure strain curve reminiscent of a stiff
chamber despite preserved LVEF ( Figure 6).