# Usability of CHA2DS2VASC score in predicting the effectiveness and safety of pharmacological cardioversion – data from the multicenter cardioversion with intravenous ANTazoline study

## TL;DR

This study found that the CHA2DS2VASC score does not predict success or safety of drug-based heart rhythm restoration in atrial fibrillation patients.

## Contribution

Shows CHA2DS2VASC score is not useful for predicting pharmacological cardioversion outcomes in real-world AF patients.

## Key findings

- Success rates of sinus rhythm restoration were similar across CHA2DS2VASC score groups.
- Adverse event rates were low and not significantly different between groups.
- Antazoline was most effective in low-risk patients while propafenone worked better in moderate-risk patients.

## Abstract

Pharmacological cardioversion (PCV) is one of the therapeutic options within rhythm control strategies for atrial fibrillation (AF). Data on clinical determinants influencing its effectiveness and safety in real-world settings remain limited.

This study is a sub-analysis of the multicenter Cardioversion with Intravenous Antazoline in Atrial Fibrillation II (CANT II) registry. The registry retrospectively included consecutive patients with recent-onset AF undergoing urgent PCV in six Polish centers between 2019 and 2020. We analyzed 931 patients stratified according to CHA₂DS₂-VASc score: Group I (0–1 points; n = 194), Group II (2–4 points; n = 580), and Group III (≥5 points; n = 157). The primary endpoint was successful restoration of sinus rhythm within 12 h, and the secondary endpoint was a composite of adverse events (death, syncope, bradycardia, hypotension).

The median age was 69 years, 48% were men, and the median CHA₂DS₂-VASc score was 3. Antazoline was used in 59% of patients, amiodarone in 53%, and propafenone in 19%. Sinus rhythm was restored in 69%, 70%, and 64% of patients in Groups I, II, and III, respectively (p = 0.45). The overall adverse event rate was low (2.1%) and did not differ significantly between groups (p = 0.16). Antazoline was most effective in Group I, while propafenone showed higher efficacy in Group II.

In this retrospective sub-analysis of the CANT II registry, success of pharmacological cardioversion of AF is not associated with number of comorbidities as assessed by the CHA2DS2VASc score. PCV remains a feasible and generally safe option in emergency and cardiology department practice.