Home monitoring in patients with implantable cardiac devices: is there a potential reduction of stroke risk? Results from a computer model tested through monte carlo simulations.

INTRODUCTION: Patients with pacemakers and implantable defibrillators (ICD) may experience asymptomatic atrial fibrillation (AF), detected with a delay depending on the in-person follow-up schedule. Home monitoring (HM) remote control with automatic alerts for AF may drive early anticoagulation, potentially reducing stroke risk. METHODS AND
RESULTS: A sample of 136 pacemaker (103) and ICD (33) patients with or without cardiac resynchronization therapy not taking anticoagulation at implant were monitored remotely with HM. Upon HM alerts for AF, patients were recalled to update therapy. Two-year data were entered in a computer Monte Carlo model, simulating 4,000 virtual subjects with the same AF and CHADS(2) stroke risk distribution of our real population. Simulations reproduced a 2-year follow-up. Two thousand subjects were supposed to be followed with HM (HM group) and 2,000 with standard in-person follow-up (SF group) at 3, 6, 9, or 12 months. Two-year Kaplan-Meier cumulative probability of >/=24-hour AF was 15.6% (95%CI 8.5-23.3%); the AF-related symptom rate was 27% and the median CHADS(2) score was 2. As a result of simulations, stroke incidence in case of AF was 2.3 +/- 1.1% in the HM group and 2.4 +/- 1.1%, 2.5 +/- 1.2%, 2.7 +/- 1.2%, and 2.9 +/- 1.3% in the SF group with 3-, 6-, 9-, and 12-month follow-up programs, with odds ratios of 0.97 (95%CI 0.93-1.01), 0.91 (0.88-0.95), 0.87 (0.84-0.90), and 0.82 (0.79-0.85) (HM better if odds ratios <1), respectively.
CONCLUSIONS: Daily HM potentially reduces the stroke risk by 9% to 18% with respect to SF with intervisit intervals of 6 to 12 months.