OGINOSAWA, Y., et al.: The Incidence and Risk Factors For Venous Obstruction After Implantation of Transvenous Pacing Leads. Several investigators have shown that the incidence of venous obstruction after pacemaker implantation was observed in 31–50% of pacemaker patients. However, these previous reports did not investigate the venous system prior to implantation. The aim of this study was to determine the incidence and risk factors for venous obstruction in patients with transvenous pacing leads. The study included 131 consecutive patients (64 men, 67 women; mean age 71.3 ± 9.8 years) who were investigated using intravenous digital subtraction angiography (DSA) before and after permanent pacemaker implantation. Follow‐up DSA was performed for a mean interval of 44 ± 6 months after pacemaker lead implantation in 79 of 131 patients. A diameter narrowing > 60% was defined as an obstruction. Prior to implantation of pacing leads, venous obstruction was present in 18 (13.7%) of 131 patients. In 15 of these 18 patients, the obstruction was present at the site of the left innominate vein. Follow‐up DSA, after implantation of pacing leads, showed that venous obstruction was observed in 26 (32.9%) of 79 patients. There were no significant differences between obstruction and nonobstruction groups in terms of age, sex, cardiothoracic ratio, left atrial dimension, left ventricular ejection fraction, baseline heart diseases for indication of pacemaker implantation, or number and body size of pacing leads. Neither clinical symptoms nor abnormal physical findings were observed in any patients. In conclusion, the incidence of venous obstruction after pacing lead implantation is less than that of previous reports, which might be related to the incidence of venous obstruction before pacing leads implantation.