A ruptured aneurysm of the sinus of Valsalva was diagnosed by Doppler, colour, and cross sectional echocardiography in a consecutive series of seven patients. The diagnoses were confirmed at operation without cardiac catheterisation. Examination by pulsed and continuous Doppler echocardiography showed continuous turbulence in six patients with aneurysms rupturing into the right ventricular outflow tract and in the patient with rupture of an aneurysm of the non-coronary sinus into the right atrium. Colour Doppler echocardiography showed turbulent flow across the defects in all seven patients. A ventricular septal defect with aortic regurgitation was detected in one patient and an associated ventricular septal defect in another. Doppler, colour, and cross sectional echocardiography were useful non-invasive techniques for diagnosing a ruptured aneurysm of the sinus of Valsalva without the need for cardiac catheterisation.