OBJECTIVETo evaluate the clinical features in Chinese patients with apical hypertrophic cardiomyopathy (AHCM) and typical hypertrophic cardiomyopathy (HCM).

METHODSThis retrospective analysis included 160 patients hospitalized in Fuwai hospital. Patients were divided into three groups: apical hypertrophic cardiomyopathy (AHCM, n = 41) group, non-obstructive typical hypertrophic cardiomyopathy group [NOHCM, LVOT < 30 mm Hg (1 mm Hg = 0.133 kPa) at rest, n = 52] and obstructive typical hypertrophic cardiomyopathy (OHCM, LVOT ≥ 30 mm Hg at rest, n = 67). Clinical features, diagnosis, therapy, and plasma levels of biomarkers of these three groups were analyzed.

RESULTS(1) The age at disease onset was older in AHCM group than in OHCM group [(49.9 ± 13.6) years vs. (41.4 ± 14.6) years, P < 0.01]. Exertional dyspnea appeared more often in HCM patients than in AHCM patients, NT-proBNP level was significantly lower in AHCM patients than in OHCM patients (P = 0.001). Plasma CK-MB, LDH, TnI and MYO levels were similar among the three groups. (2) Thirty-three AHCM patients were first hospitalized for suspected coronary heart disease (CHD) and CHD was excluded in 18 cases (43.9%). (3) The frequency of giant negative T waves (depth ≥ 10 mm) on ECG was 43.9%, 13.5% and 4.4% (P < 0.01) in AHCM, NOHCM and OHCM respectively. Half of AHCM patients showed left ventricular high voltage on ECG. (4) Cardiac magnetic resonance imaging is superior to echocardiography on correctly diagnosing AHCM.

CONCLUSIONAHCM patients differ from typical OHCM patients in clinical characteristics. There were significant differences on echocardiography and electrocardiography features among three groups. Cardiac magnetic resonance imaging and giant negative T waves on ECG are helpful for the diagnosis of AHCM.