TRANSTHORACIC DOPPLER-ECHOCARDIOGRAPHIC ANALYSIS OF PHASIC CORONARY BLOOD-FLOW VELOCITY IN HYPERTROPHIC CARDIOMYOPATHY

Objective-To use transthoracic Doppler echocardiography to assess coro nary blood flow non-invasively in patients with hypertrophic cardiomyo pathy. Design-High frequency transthoracic Doppler echocardiography wa s used to assess resting phasic coronary velocity patterns in patients with hypertrophic cardiomyopathy and to define the relation between c oronary flow patterns and clinical, echocardiographic, and haemodynami c manifestations of this condition. Setting-A tertiary referral cardio thoracic centre. Methods-Fifteen patients (10 men and five women, mean (SD) age 49 (10.3) years) with asymmetric hypertrophic cardiomyopathy underwent high frequency (5 MHz) transthoracic Doppler echocardiograp hic assessment of the left anterior descending coronary artery. In add ition, standard two dimensional echocardiography was performed. The re sults were compared with 16 normal participants (nine men and seven wo men, mean age 61.2 (10.7) years) who had no evidence of cardiac diseas e. Results-Biphasic diastolic predominant coronary artery blood veloci ty profiles were obtained in all patients and controls. Systolic peak blood velocity and velocity time integral were significantly reduced i n the hypertrophic cardiomyopathy group compared with controls (11.3 ( 15.8) cm/s and 1.09 (1.78) cm v 20.5 (13.1) cm/s and 4.23 (2.80) cm, r espectively, P < 0.05). A reversed pattern of systolic blood flow velo city was found in three patients with severe anterior wall and septal hypertrophy. During diastole there was prolongation of the diastolic a cceleration (203 (53) ms v 110 (60) ms in controls, P < 0.05) and dece leration times (487 (200) ms v 210 (90) ms in controls, P < 0.05). The re was no significant difference between those with and without sympto ms or a left ventricular outflow tract gradient. Conclusions-Patients with hypertrophic cardiomyopathy have abnormal systolic and diastolic coronary flow profiles at rest when measured by transthoracic echocard iography.