Venous thrombosis after long-term transvenous pacing in the Chinese.

To determine the incidence of venous thrombosis after long-term transvenous pacing in the Chinese, venograms were performed in 50 consecutive Chinese patients seen at the pacemaker clinic. There were 25 women and 25 men. The mean age was sixty-six years (range thirty-two to eighty-one). The indications for pacing were complete heart block in 16 patients and sick sinus syndrome in the remainder. All pacemakers were of the single-chamber ventricular pacing type and had been implanted for a mean period of four years (range two to seven). In 27 patients the route of entry for the pacing electrode was through the cephalic vein and in the other 23 patients the subclavian veins were used. Of the 50 venograms, 1 showed partial and 1 showed total obstruction at the subclavian vein. Both patients (4%) were asymptomatic. All others (96%) were normal. The incidence of venous thrombosis was not related to the routes of entry of the pacing electrodes. All patients tolerated the procedure well and had no complications. It is concluded that the incidence of venous thrombosis after long-term transvenous pacing is extremely low in the Chinese (4%), and venograms are both safe and useful for identifying venous thrombosis related to transvenous pacing.