Background:
Pneumothorax as an early complication from pacemaker implantation arise with a frequency between 0.9% and 1.9%. However, the usual presentation of pneumothorax is ipsilateral to the subclavian vein where the catheter is being inserted.

Material and methods:
We introduce below an uncommon case of contralateral pneumothorax after a pacemaker implantation through a catheterization of the left subclavian vein.

Results:
An 87-year-old male patient permanent pacemaker implantation four days ago came to the Emergency Room with right pleuritic chest pain and associated dyspnea for four days, stating that the symptoms began after the pacemaker implantation. On admission the physical exam was normal, hemodynamically stable, afebrile and basal oxygen saturation of 99 % without cardiopulmonary auscultation findings. Electrocardiogram with sinus rhythm at 50 bpm without alterations and chest radiography suggestive of right pleural effusion. Chest X ray after the pacemaker implantation was reviewed (Left subclavian access) describing a right pneumothorax. Assessment was completed with a Chest CT describing a right hemopneumothorax. Anterior drainage is decided after being admitted to the Thoracic Surgery Service. Iatrogenic right pneumothorax after pacemaker implantation diagnosis was made. Arrhythmia Unit considered the release of one of the active fixation system during the procedure as the most probable cause of the hemopneumothorax. There was not a perforation in the auricular cable's current location.

Conclusions:
This exceptional case shows how Doctors should be aware of infrequent complications related to ordinary procedures and keep in mind the signs and symptoms to do the differential diagnosis.