Long-term performance of right ventricular pacing leads: risk factors associated with permanent right ventricular pacing threshold increase

Abstract

Purpose: Right ventricular pacing threshold (RVPT) may rise over time accompanied by the increased use of implantable cardiac pacemakers. However, risk factors for permanent RVPT increase are not fully clarified in patients without definite lead fracture and dislodgment. We aimed to evaluate the long-term performance of RV pacing leads and identify risk factors associated with the occurrence of permanent RVPT increase in this population.

Methods: Patients with first implantation of cardiac pacemakers from January 2008 to June 2016 were consecutively enrolled. Follow-up for RVPT increase was until December 2017. The clinical data, specific data on the pacemaker implantation, and routine follow-up were retrieved.

Results: During a follow-up duration of 5.4 ± 2.1 years, permanent RVPT increase (except lead fracture and dislodgment) was found in 8.4% (87/1033) patients. Patients with permanent RVPT increase had higher prevalence of myocardial infarction (MI), diabetes, and the use of amiodarone. The risk factors independently associated with permanent RVPT increase were MI (HR = 1.094, 95% CI 1.014-1.180, p = 0.031), diabetes (HR = 2.804, 95% CI 1.064-3.775, p = 0.003). MI patients with RVPT increase had higher prevalence of multivessel disease and atrioventricular block. Diabetic patients with RVPT increase exhibited higher serum fasting blood glucose (FBG) and hemoglobin A1c (HbA1c) levels, which were correlated with the maximum RVPT (p < 0.001).

Conclusions: Our data showed that permanent RVPT increases (except lead fracture and dislodgement) during long-term follow-up after pacemaker implantation. The likely risk factors predisposing to chronic permanent RVPT increase are MI and diabetes with higher FBG and HbA1c levels.

Keywords: Cardiac pacemaker; Diabetes mellitus; Myocardial infarction; Right ventricular pacing threshold.

Fig. 1

Patient selection flow. After excluding patients who were chronically bedridden (n = 7) and who were lost to follow-up (n = 12), we ultimately enrolled 1033 eligible patients

Fig. 2

Patients with right ventricular pacing threshold (RVPT) increase during follow-up. Onset of RVPT increase was traced back by the devices. Patients were allocated according to the time of their maximum RVPT reached. The maximum RVPT increase occurred within the first year from implantation in 13.8% (15/109) patients, within the second year in 19.3% (21/109) patients, between the third and the sixth year in 58.7% (64/109) patients, and after the sixth year in 8.2% (9/109) patients

Fig. 3

Changes in serum fasting blood glucose (FBG) levels (a) and changes in serum hemoglobin A1c (HbA1c) levels (b) at periodic intervals during follow-up, comparing diabetic patients with and without permanent right ventricular pacing threshold (RVPT) increase. The differences were significant at every time point between two groups (p < 0.05). The mean serum FBG level was higher in diabetic patients with permanent RVPT increase (9.39 ± 0.75 vs 7.70 ± 0.79, p = 0.001). The mean serum HbA1c level was higher in diabetic patients with permanent RVPT increase (8.01 ± 0.52 vs 6.82 ± 0.44, p = 0.001)

Fig. 4

a Correlation between maximum ventricular pacing threshold values and mean serum fasting blood glucose (FBG) levels during follow-up in the diabetic patients. b Correlation between maximum ventricular pacing threshold values and mean serum hemoglobin A1c (HbA1c) levels during follow-up in the diabetic patients