Objective To investigate the risk factors that may induce pneumothorax resulted from subclavian vein puncture during interventional therapy for arrhythmia.Methods The clinical data of 4 351 patients with heart disease,who were admitted to Wuhan Asia Heart Disease Hospital,China,during the period from January 2010 to January 2014 to receive subclavian vein puncture for the performance of radiofrequency catheter ablation or pacemaker implantation,were retrospectively analyzed.The gender,age,presence of chronic obstructive pulmonary disease (COPD) and the shape of clavicle of patients who developed pneumothorax were analyzed,and their relationships with the occurrence of pneumothorax were evaluated.Results Of the 4 351 patients,47 patients developed pneumothorax(1.08％),their age was 12-72 years old with a mean of (47.1±18.4) years old.Among the 47 patients,37 patients were females (78.7％).The angle between clavicle and sternum ＜60°(oblique clavicle) was seen in 27 patients,coexisting COPD was seen in 2 patients.The occurrence of pneumothorax was strikingly higher in females than that in males (OR=2.7,95％ CI=1.4-5.2).In patients with oblique clavicle the risk of pneumothorax was obviously increased (OR=3.5,95％ CI=1.6-7.9) and in patients with COPD the probability of pneumothorax was remarkably increased (OR=2.3,95％CI=1.2-4.7).No special treatment was employed in 5 pneumothorax patients,and the pneumothorax was absorbed by itself.In 19 patients,the pneumothorax was relieved through thoracic puncture and suction.Closed drainage of thoracic cavity was employed in 23 patients.All patients were discharged from hospital with complete rehabilitation.Conclusion Clinically,pneumothorax has been an important clinical problem in interventional therapy.In female patients and in patients who have oblique clavicle or coexisting COPD,pneumothorax is more likely to occur when they receive subclavian vein puncture.