The Symptoms and Clinical events associated with Automatic Reprogramming (SCARE) at replacement notification study

Pacemaker patients experience battery depletion that activates pacemaker's alert for replacement notification. Automatic reprogramming at replacement notification can result in loss of rate response and atrioventricular (AV) synchrony.

To determine if relevant symptoms or clinical events may be associated with automatic reprogramming at replacement notification.

Electronic medical record review was undertaken for 298 patients referred for pacemaker generator replacement. Primary endpoints were symptoms or clinical events during replacement notification period.

Following elimination of duplicate pacemaker replacements (n = 12), "near-replacement notification" or "recalled" (n = 15) and pacemakers at "end of life" (n = 5), 266 subjects were included. Three distinct reprogramming cohorts were identified; those with no change (control) in pacing mode (n = 46), those with loss of rate response (n = 154), and those with loss of AV synchrony ± rate response (n = 66). In total, 83 subjects (31.2%) had symptoms with significant differences seen between groups (control = 4.3%, loss of rate response = 26.0%, loss of AV synchrony ± rate response = 62.1%, P < 0.001). Overall, 28 subjects (10.5%) experienced clinical events with significant differences seen between groups (control = 0.0%, loss of rate response = 6.5%, loss of AV synchrony ± rate response = 27.3%, P < 0.001).

Automatic reprogramming at replacement notification was associated with significant symptoms in 26% of those who lost rate response and in 62% of those who lost AV synchrony ± rate response. Additionally, 27% of the latter cohort required nonelective clinical care.