Relation Between Clinical Variables at Initial Evaluation and Outcomes*.

SCD = sudden cardiac death, Max LV = maximum left ventricle, LVOT = left ventricular outflow tract, NYHA = New York Heart Association, HF = heart failure.*Adjusted Multivariate Cox Proportional Hazards Analysis. Hazard risk based on multivariate Cox regression analysis including age, syncope, sudden death family history, maximum left ventricular wall thickness, left atrial diameter, atrial fibrillation, left ventricular outflow obstruction defined as gradient ≥30 mmHg at rest and NYHA functional class at initial evaluation.#NYHA functional class II compared to class I.&Patients with LVOT obstruction, who had not received septal reduction therapy (including myectomy and alcohol ablation) compared to all others; patients with syncope who had not received invasive treatment (including implantation of implantable cardioverter defibrillator, pace maker and septal reduction therapy) compared to all others.