RESUMO
BACKGROUND: Complete heart block (CHB) is a common complication of cardiac surgery, which may resolve spontaneously. The optimal number of days to wait for resolution of CHB prior to proceeding with a permanent pacemaker (PPM) and the long-term utility of PPMs placed in this setting remain uncertain. METHODS AND RESULTS: This was a retrospective cohort study, which included members of Kaiser Permanente Northern California who had cardiac surgery, a PPM placed within 30 days after surgery, and one year of follow-up time. Chart review was performed to determine the frequency of ventricular pacing at each PPM interrogation visit up to one year after surgery. A PPM was categorized as underutilized at the time of an interrogation if none of the following were present: underlying rhythm <40 bpm, persistent CHB, or >1% ventricular pacing. The study included 247 patients with a mean time from cardiac surgery to PPM of 6.5 days. In 33 cases (13%), underutilized status was confirmed. The time from surgery to PPM implant was significantly higher in the underutilized group (8.1 ± 4.2 days vs. 6.2 ± 4.2 days, p = 0.003). CONCLUSIONS: The majority of PPMs placed early after cardiac surgery are not underutilized. In this retrospective, observational study, longer delay from surgery to PPM implantation was not associated with a greater likelihood that the PPM would be utilized long term. A prospective study is required to determine optimal timing of PPM implantation in this setting.