Introduction: Patients with hypertrophic obstructive cardiomiopathy (HOCM) need beta-blockers therapy,but in some cases with LVOT gradient above 50mmhg the surgical treatment is indicated to reduce the outflow gradient. The aim of this paper is to present a patient with high degree of LVOT obstruction who underwent surgery and whose objective status became better and subjective symptoms disappeared. Case report: 24 years old female patient with nocturnal dyspnea,chest pain and fatigue,mesosystolic murmur was found above Erbs point. ECG showed left ventricular hypertrophy with ST segment and T wave abnormalities. Transthoracic echocardiography (TTE) revealed left ventricular hypertrophy-septum and anterolateral free wall,systolic anterior motion (SAM) of anterior leaflet of the mitrale valve,narrowing of the LVOT with peak gradient PG 135mmhg,MPG 69,6mmhg,moderate mitrale regurgitation.Myotomy-myectomy of interventricular septum was done. Postoperative echocardiography showed the site of myectomy (Scooped-out portion of ventricular septum) with residual SAM and LVOT PG 65,8mmhg ,MPG 29,1mmhg. Endomyocardial biopsy confirmed the diagnosis of primary HOCM. Conclusion: Echocardiography is the most reliable method in diagnosis of HOCM and assessment of LVOT gradients . It is quite sufficient method to access surgical treatment,when indicated.