Background: Catheter ablation is a first-line treatment of symptomatic atrioventricular nodal reentrant tachycardia (AVNRT). The procedure has been associated with a risk of persistent heart block (HB) requiring pacemaker that has been historically reported up to 2.0%, however recent analyses suggest that this risk is much lower in the current era.
Objective: To report trends in the risk for HB post AVNRT ablation over an 18-year period in 2 tertiary hospitals and identify predictors.
Methods: Consecutive patients undergoing catheter ablation for AVNRT from January 2001 to June 2019 at 2 tertiary hospitals were included. Variables including age, gender, repeat ablation, operator experience, energy used, fluoroscopy time, inpatient status and use of electroanatomical mapping (EAM) were included in univariate and multivariate models to predict HB post ablation.
Results: We report an overall risk for PM post ablation of 1.3% in a series of 1708 patients. The risk showed a steady decline over time, with risk of 1.99% vs 0.59% in the first vs the second 10 years of observation, respectively (p = 0.018). Multivariate analysis showed that age > 70 (OR 11.33, CI 4.141-30.972, p<0.001) and no use of EAM (OR 4.338, CI 1.452-12.963, p = 0.009) were the only independent predictors of HB.
Conclusion: The risk of pacemaker implant post AVNRT ablation has significantly declined over the last 18 years. No use of EAM and older age are the only independent predictors of HB in our series.
Table 1: Independent Predictors of Risk for Pacemaker Implantation Post Ablation | No EAM (n=897) | EAM (n=811) | All cases (n=1708) | P value |
| Age < 50 (n=577) | 3/329 (0.9%) | 0/248 (0%) | 3/577 (0.5%) | 0.132 |
| Age >=50 and <75 (n=849) | 7/422 (1.7%) | 0/427 (0%) | 7/849 (0.8%) | 0.008 |
| Age >=75 (n=282) | 8/146 (5.5%) | 4/136 (2.9%) | 12/282 (4.3%) | 0.291 |
| All cases (n=1708) | 18/897 (2%) | 4/811 (0.5%) | 22/1708 (1.3%) | .006 |
| P Value | 0.004 | 0.000047 | 0.000007 | |
