Clicks and Sounds (Whoops) in Left-Sided Pneumothorax

Clinical and Phonocardiographic Study

¹ Department of Medicine, Division of Cardiology and Heart Center, University Clinic St. Rafael, Leuven, Belgium

Five patients with a small left-sided pneumothorax and loud peculiar sounds over the precordium were observed. The phonocardiographic features were studied and it was found that the extra-sounds usually were multiple and occurred both in systole and diastole. Their frequency, intensity and time relationship to the heart sounds varied with respiration and position of the patient. The most striking finding, however, was the presence in four patients of murmurs which in three cases resembled what has been called a " systolic whoop" or "precordial honk." An extracardiac origin for these sounds was accepted and they were explained by the forceful heart action on air pockets trapped in the pleural cavity near the left ventricle. Correspondingly, it was suggested that "systolic whoop sounds," heard over long periods in patients without dysfunction of the mitral valve, could be explained by subpleural blebs facing the left ventricle and subjected to its forceful contractions.