Actual pacemaker longevity: the benefit of stimulation by automatic capture verification.

BACKGROUND

We evaluated the impact of an algorithm for automatic right ventricular (RV) stimulation compared to fixed-output pacing (FOP) stimulation on actual pacemaker longevity over a 9-year follow-up.

METHODS

Prospective observation of 300 patients implanted with VDDR/DDDR pacemakers in 1999-2000 up to October 31, 2008. Sixty-one patients were paced by Autocapture pacing (ACP), 239 were paced by FOP; they were seen twice yearly at the pacemaker clinic. Factors known to affect pacemaker longevity were collected: median heart rate, %A&V paced activity, pacing output, and impedance. Patients dead before pacemaker replacement, lost to follow-up, or who developed permanent atrial fibrillation were excluded from analysis.

RESULTS

One hundred twenty-six of three hundred patients completed the study. Adverse clinical events due to an increased RV threshold occurred in two FOP patients compared to none among ACP. Pacemaker replacement occurred in 1/34 ACP patients versus 60/92 FOP patients (P < 0.001). ACP was the single independent predictor of pacemaker longevity at multivariable analysis (hazard ratio = 0.03, P < 0.001) either in the overall population or in the specific patients subgroups (sick sinus syndrome, atrioventricular block, and neurally mediated syncope).

CONCLUSIONS

Automatic verification of stimulation is reliable at long term, and warrants superior safety in the event of pacing threshold changes. It allows a significant longevity increase compared to FOP stimulation that may heavily impact the patients' quality of life and the cost of pacing therapy. Moreover, it is a fundamental technology in a strategy of remote patient and device monitoring, and may enable automatic device follow-up operated by trained, nonmedical personnel.