Characterization of superresponders to cryoballoon ablation

Abstract

Abstract Background Isolation of pulmonary veins is the cornerstone in the treatment of symptomatic atrial fibrillation rather with radiofrequency or cryo balloon. Recurrence rate is quite common in the long term follow up, clearly related to previosly described factors. Nevertheless some patients maintain sinus rhythm forever after the index ablation. The aim of this study is characterize this kind of patients (so called superresponders). Methods This is a Unicentric, retrospective, consecutive study including all patients summited for cryoablation in our hospital from January 2011 to September 2020. We looked for clinical, electrical, echocardiographic variables and those linked to the ablation procedure. A transversal FU to discard recurrences was done. A univariate and multivariate logistic regression was performed. Results We included 422 patients, 193 of them were finally excluded: 21 lost in the FU, 30 got radiofrequency ablation and 142 did not reach a minimum 5 years FU. About the 229 finally included, 85 (group 1) didn't have any recurrence during the FU, in front of 144 (group2) with recurrences. The univariate analysis showed that grup 1 patients were younger, the rate of hypertension, CHA2DS2VASc score, moderate sleep apnea, body mass index (BMI), p wave duration, and the size of left atrial was lower in grup 1 in front of patients of grup 2. Left ventricular ejection fraction was higher and the number of pulmonary veins in whom the temperature was lower than −40°C in grup 1 in front to grup 2. In the multivariate analysis the p wave duration: OR 0.92; 95% CI [0.89–0.94]; p<0.001, BMI kg/m2: OR 0.74; 95% CI [0.65–0.85]; p<0.001, a temperature <−40°C in all the targeted veins: OR 3.52 95% CI [1.45–8.54]; p=0.005 and SR on the ablation index day OR: 7.29; 95% CI [1.53–34.71]; p=0.012, maintained statistical significance. Conclusions In our series patients with a p wave duration, BMI, SR the ablation index day and achieving a temperature <−40°C in all the targeted veins, resulted as protective factors to maintain SR in the long term FU. An adequate selection of patients can improve results and optimize resources. Funding Acknowledgement Type of funding sources: None.