Prediction of sinus tachycardia after cardioneuroablation: the utility of atropine test

Abstract

Abstract Background Acceleration of sinus rhythm (SR) due to parasympathetic denervation of sinus note is a favourable sign during cardioneuroablation (CNA) for the treatment of functional bradyarrhythmias. On the contrary, a faster heart rate may be symptomatic in some patients. Purpose We investigated predictors of sinus tachycardia at the 3-month post-CNA visit. Methods An atropine test (2 mg IV) was performed before the procedure. The endpoint of CNA was complete denervation of the sinus node as assessed by extracardiac vagus nerve stimulation. Sinus tachycardia was defined as a sinus rate ≥100 bpm at the 3-month post-CNA outpatient visit. Factors independently associated with post-CNA SR were investigated by multivariate analysis. Using regression coefficients, a composite continuous-scale index (CCSI) estimating the post-CNA SR was constructed and used for sinus tachycardia prediction. Results The study included 160 patients aged 40 ± 12 years, 56% men, with baseline SR of 63 ± 15 bpm, post-atropine SR of 107 ± 21 bpm, and SR 3-month post-CNA SR of 83 ± 15 bpm. Nineteen patients had sinus tachycardia at a 3-month visit after CNA. Age, gender, baseline SR and post-atropine SR were significantly (and the latter two independently) associated with 3-month post-CNA SR. The CCSI (defined as 36 + 0.32 * baseline SR + 0.25 * post-atropine SR) correlated with 3-month post-CNA SR (Figure) and provided an area under the curve of 0.87 in the analysis of receiver operating characteristic. The CCSI >90 predicted the 3-month post-CNA sinus tachycardia with a sensitivity of 74% and specificity of 86%. Conclusion Sinus tachycardia at 3 months after CNA can be predicted by the baseline and post-atropine sinus rate. This can help to select patients who may benefit from less rigorous sinus nodal denervation to avoid potentially symptomatic sinus tachycardia after the CNA.