Abstract P027: Yamaguchi Syndrome Presenting With Atrial Fibrillation And Heart Failure Diagnosed With Contrast Echocardiography

Abstract

Yamaguchi syndrome or apical hypertrophic cardiomyopathy (ApHCM), is a rare variant of hypertrophic cardiomyopathy (HCM), prevalence of about 3% among HCM population in the United States. Generally considered a benign condition but can be potentially life-threatening. A 84 year old female with history of mitral regurgitation with mitra-clip, paroxysmal atrial fibrillation (pAF) presented to ED with dyspnea and leg swelling. She was tachypneic with bibasilar rales, jugular venous distention. BNP 1,086 pg/l with cardiomegaly and pulmonary edema on chest x-ray. She was managed for acute decompensated cardiac failure (NYHA class III) using IV furosemide with symptom improvement. EKG revealed AF with abnormal deep T-wave inversion most prominent in precordial leads (V4-V6). Contrast echocardiogram revealed ApHCM, missed on prior echocardiograms. Patient’s dose of metoprolol was doubled, and outpatient follow-up was scheduled. Conclusion: ApHCM commonly presents with heart failure symptoms, chest pain, palpitation, or syncope. Undiagnosed/untreated ApHCM can lead to complications including diastolic dysfunction, left atrial enlargement causing atrial fibrillation, apical clots formation with subsequent thromboembolism, ventricular wall aneurysm, arrhythmias, and myocardial infarction. In our case, contrast echocardiogram was able to diagnose ApHCM. A presentation of heart failure symptoms at NYHA class II or higher is a known predictor of poor prognosis in patients with ApHCM. Missing diagnosis on normal echocardiogram without use of ultrasound contrast is very common. Diagnosing with proper use of modality can help to improve outcomes in these patients.