A diastolic murmur is informative in the diagnosis of valvular heart disease, such as mitral stenosis and aortic regurgitation. Patients with hypertrophic cardiomyopathy (HCM) could have diastolic murmurs, although this is not widely recognized. We describe an illustrative case of HCM which was found to have a diastolic murmur associated with mid-left ventricular obstruction. An asymptomatic 65-year-old male was referred because of an abnormal electrocardiogram. Cardiac auscultation showed a soft fourth heart sound, a systolic ejection murmur, and a third heart sound followed by a diastolic murmur at the apex. On phonocardiography, the mid-diastolic murmur was predominantly low-pitched with an onset of about 200 ms after the second heart sound and a duration of approximately 150 ms. The timing of the diastolic murmur was consistent with an increased blood inflow during diastole in the mid-ventricular obstruction (2.0 m/s), which was produced by narrowing between the hypertrophied ventricular septum and the protrusion of the anterior papillary muscle. <Learning objective: A diastolic murmur is common in valvular heart diseases, such as mitral stenosis and aortic regurgitation, and can also be heard in hypertrophic cardiomyopathy although not widely recognized. We report an illustrative case of hypertrophic cardiomyopathy with a diastolic murmur related to mid-left ventricular obstruction, findings that would highlight the importance of auscultation regarding not only the differential diagnosis but also risk stratification, given the possible association of diastolic murmurs with adverse outcomes, even in the era of advanced imaging techniques.>.
Keywords: Diastolic murmur; Echocardiography; Hypertrophic cardiomyopathy; Mid-ventricular obstruction; Phonocardiogram.