Hypertrophic Cardiomyopathy (HCM) has several distinct morphological patterns. Asymmetric left ventricular hypertrophy with outflow obstruction, mid-cavity obstruction and apical hypertrophy are types of morphological variants in HCM. Apical aneurysm formation is an uncommon feature associated with HCM. Apical aneurysms have been described in the asymmetric septal, apical, and mid-cavity obstruction types of HCM. We describe a patient with HCM presenting with mid-cavity obstruction and apical aneurysm, and show unusual flow patterns within the apical aneurysm detected on Doppler echocardiography.
A 62-year-old male investigated for an episode of syncope showed non-sustained ventricular tachycardia and required hospitalization. Past medical history included cerebrovascular accident and hypertension. Echocardiography revealed severe left ventricular hypertrophy, hyperdynamic left ventricular (LV) function, mid-cavity obliteration of the LV in systole, and a small localized apical aneurysm. Doppler echocardiography showed a mid-cavity gradient of 36 mm Hg without any LV outflow tract gradient. In addition, Doppler echocardiography revealed abnormal flow originating from the apical aneurysm towards mid cavity during the isovolumic relaxation period of diastole. This resulted as the apex was excluded from the remaining LV chamber during systole. A pressure gradient then developed between the aneurysm and LV cavity. Coronary arteriography showed an occluded right coronary artery and diffuse disease in the left anterior descending coronary artery. The patient was managed conservatively with beta-blockade due to his dementia.
The interesting features in this patient are the presence of mid-cavity obstruction and an associated apical aneurysm exhibiting paradoxic diastolic flow. Apical aneurysms occur in HCM rarely. Pathophysiologic mechanisms remain speculative, but abnormal myocardial vasculature, septal perforator artery compression, oxygen supply-demand mismatch, and pressure overload are thought to be important contributing factors. Patients with apical aneurysms and HCM have an increased frequency of embolic phenomena and as such should be considered for anticoagulation.
Hypertrophic cardiomyopathy with mid-cavity obstruction, apical aneurysm, and paradoxic diastolic flow is a rare entity. It is best diagnosed with echocardiography. Patients with this condition should be treated with negative inotropic agents and ICD placement to prevent SCD. In addition, anticoagulation should be considered to reduce the risk of embolic events even in the absence of atrial fibrillation.
Beau Hawkins, None.