A 3-year-old Selle Français entire male presented to the Clinique Equine, Ecole Nationale Vétérinaire d'Alfort, for standing laparoscopic closure of the inguinal rings, to prevent recurrence of a strangulated inguinal hernia. An incidental, iatrogenic pneumothorax was induced during the procedure. Just after the pneumothorax occurred, a heart murmur, not present during the preoperative physical examination, could be auscultated. Relevant echocardiographic examination could not be achieved, due to the air in the thorax. Upon complete resolution of the pneumothorax 2 days later, however, the heart murmur resolved, and no abnormal changes were diagnosed on echocardiographic evaluation. This paper reports the diagnosis and clinical management of an iatrogenic pneumothorax and its associated transient heart murmur.