Prevalence and co-incidence of symptomatic idiopathic sinus tachycardias and symptomatic vagally mediated bradyarrhythmias before and after cardioneuroablation

Sinus tachycardias (ST) may be associated with symptomatic, functional, vagally mediated bradyarrhythmis referred for cardioneuroablation (CNA). Moreover, the incidence of de novo pathological ST (defined as ST within the first 6 months after CNA), inappropiate sinus tachycardia (IST) and postural orthostatic tachycardia syndrome (POTS)] are a potential side effects of the procedure and require innovative management strategies including SN sparing hybrid ablation (SNS). The study sought to validate the prevalence, co-incidence and management of ST/IST/POTS in patients with VMB referred for CNA.

Data were collected from the Polish multicenter CNA (POL-CA) registry (POL-CA). All consecutive patients referred for the first extra cardiac vagal nerve stimulation (ECVS)-guided CNA with symptomatic VMB were retrospectively analyzed. In all patients standardized cardiovascular autonomic test (CAT) and active standing test were performed off-drugs before and when neccessary after CNA procedure to classified patients with the symptoms of IST/POTS. During shared-decision making several options were discussed with the patients (CNA only, CNA+drugs, SNS only, CNA+SNS, Pacemaker+drugs+SN ablation, etc). Patients requiring treatment for de-novo symptomatic ST within 6 months after CNA were classified as CNA-induced pathological ST. Patients with persistent (>12 months), symptomatic and drug-resistant CNA-induced IST/POTS were referred for SNS.

A total of consecutive 380 adult patients (mean age: 54+/-15 years; 45% women) referred for the first ECVS-guided CNA with symptomatic VMB and who completed at least 12-month follow-up were included into analysis. In 1,6% (6/380) of patients pre-procedural IST/POTS associated with VMB were documented. Those patients were classified as bidirectional (uninodal or binodal) arrhythmic syndrome. In 6/6 of patients primarily CNA were performed to establish adequate control of symptoms with (1/6) or without (5/6) drug treatment. After CNA procedure the incidence of CNA-induced de novo pathological ST were observed and treated in 23% (88/380) of patients, however additional 8% (31/380) of patients were shortly managed by ivabradine and/or bisoprolol to control tendency for borderline ST symptoms. Finally, only 0,5% (2/380) of patients with de novo CNA-induced long-standing persistent drug-resistant IST/POTS were referred for SNS.

Prevalence and co-incidence of IST/POTS with VMB referred for CNA is rare (1,5%), however 3-times higher than long-standing persistent, drug-resistant symptomatic CNA-induced IST/POTS (0,5%) requiring SNS hybrid ablation. Symptomatic CNA-induced pathological ST disappeared in majority of patients within the first 12 months. Bidirectional (uni- or binodal tachycardia-bradycardia) arrhythmic syndrome require comprehensive management with shared-decision making and including complex and hybrid non-invasive and invasive treatment.