Renal Denervation and pUlmonary Vein isolAtion With cryoabLation on Patients With Atrial Fibrillation and hypErtension

Hypertension is a major risk factor for the high morbidity and mortality of cardiovascular diseases in the world. As a common arrhythmia, the autonomic nervous system plays an important role in the occurrence and maintenance of atrial fibrillation \[1,2\]. Enhancement of central sympathetic nervous system activity and stimulation of the efferent sympathetic nerve of the heart can promote the occurrence and development of atrial fibrillation \[3\]. Hypertension is an important risk factor for the occurrence of atrial fibrillation, and the incidence of complications such as heart failure, coronary heart disease and left ventricular hypertrophy is increased in patients with atrial fibrillation with poor blood pressure control \[4-6\]. Therefore, hypertension management in patients with atrial fibrillation is particularly important. However, a 2014 study of SYMPLICITY HTN-3 with a sample size of 535 people showed that RDN could not significantly reduce blood pressure \[10\], which put the study of RDN into a dilemma. Since then, researchers have optimized the study design, and some more detailed results have suggested a significant antihypertensive effect of RDN \[11-13\]. At present, there are few reports on the cryo-ablation of renal sympathetic nerve in the RDN studies, only the case of cryo-ablation of renal artery by Dr.Prochnau et al in Germany in 2014, which is still a technical blank in China \[14\]. At present, catheter ablation has been widely recognized in the treatment of paroxysmal atrial fibrillation. In terms of patient comfort and efficacy, cryo-ablation promoted in recent years shows greater advantages than radiofrequency ablation, which has the characteristics of less damage to surrounding tissues and faster recovery of vascular endothelial function. Therefore, the application of cryoablation in the field of RDN may be similar to the effect of pulmonary vein ablation. The purpose of our study was to investigate whether renal artery cryoablation combined with pulmonary vein cryoablation reduces the recurrence rate of atrial fibrillation compared with pulmonary vein cryoablation alone.