The role of imaging in the diagnosis and management of hypertrophic cardiomyopathy

Abstract

Hypertrophic cardiomyopathy (HCM) is the most common genetic cardiomyopathy, affecting approximately 1:500 people. As the yield of genetic testing is only about 35-60%, the diagnosis of HCM is still clinical and based on the demonstration of unexplained and usually asymmetric left ventricular (LV) hypertrophy by imaging modalities. In the past, echocardiography was the sole imaging modality used for the diagnosis and management of HCM. However, in recent years other imaging modalities such as cardiac magnetic resonance have played a major role in the diagnosis, management and risk stratification of HCM, particularly when the location of left ventricular hypertrophy is atypical (apex, lateral wall) and when the echocardiographic imaging is sub-optimal. However, the most unique contribution of cardiac magnetic resonance is the quantification of myocardial fibrosis. Exercise stress echocardiography is the preferred provocative test for the assessment of LV outflow tract obstruction, which is detected only on provocation in one-third of the patients.

Two Patients with Coincident Noncompacted Myocardium and Hypertrophic Cardiomyopathy

“…7) Cine images could clearly show the location of trabeculae and visible blood flow into the deep intertrabecular recesses, highlighted in the description of apical trabecular. In our two cases, the CMR findings match the diagnosis of both LVNC and HCM: twolayered structure with a compacted epicardial and noncompacted endocardial layer with NC/C > 2.3 at enddiastole; 17) hypertrophic interventricular septum with maximum thickness more than 15 mm; 6) and there were no risk factors of the disease. Furthermore, by the specific affected myocardial segments and gadolinium enhancement, we can assess the degree of ventricular burden.…”

“…5) Currently, diagnosis of cardiomyopathies depends on non-invasive imaging studiestransthoracic echocardiography and CMR. 6,7) Case Reports Case 1: An 18-year-old man presented clinically with chest distress and polypnea for three years. His family history was negative.…”

<i>MYH7</i> Gene-Related Mutation p.V878L Identified in a Chinese Family with Hypertrophic Cardiomyopathy

“…Echocardiographic diagnostic criteria for HCM include an unexplained maximal wall thickness (measured at end-diastole) !15 mm (or > 2 standard deviation for age, height and gender) in any myocardial segment or septal/posterior wall thickness ratio of > 1.3 in a nondilated ventricle and > 1.5 in the setting of systemic hypertension. 10) Samples: Blood samples were collected from the proband and her family members. RNA-free high-molecular-weight DNA was prepared using a Tiangen Blood DNA Extraction Kit (TIANGEN[DP318-03(200)], China).…”

Role of echocardiography in the diagnosis and management of hypertrophic cardiomyopathy

“…Imaging is an integral part of the periprocedural assessment of patients who undergo myectomy 34. As direct cardiac visualisation could lead to imprecision in the extent of myectomy, intraoperative TOE has become an essential part of the procedure and should always be available during the intervention.…”