Innocent murmurs include murmurs of physiological origin occasionally murmurs originating from haemodynamically insignificant cardiac defects. Innocent murmurs caused by accelerated blood flow are common in young adults. Fever, anaemia, tachycardia and a thin or flat chest wall may intensify flow sounds making them resemble a murmur of a valvular disease. Innocent nature of the murmur is suggested by the following features: short early systolic or mid-systolic murmur, grade 1-2 point of maximum intensity beside the sternum on the left systolic ejection murmur in the pulmonary valve auscultation area normal S2 (not constantly split) no other abnormalities on auscultation good performance status, no left ventricular hypertrophy or dilatation (ECG, chest x-ray). A murmur must not be considered innocent until the patient has undergone thorough investigation. If necessary, an echocardiography should be carried out to confirm diagnosis. Diastolic murmurs always originate from an organic abnormality which may, nevertheless, be haemodynamically insignificant.