Procedural heart rate variability and its effect on short-term symptoms after cardioneuromodulation procedure

Abstract

Abstract Background Syncope is a miscellaneous clinical condition that affects a large portion of the population every year all over the world and responsible for a considerable amount of hospital and particularly emergency department admissions (1) The use of a right-sided approach in catheter ablation of ganglion plexi (GP) has been applied to reduce syncope episodes caused by vasovagal syncope (VVS) and decrease the overall burden of syncope (2). Purpose Our aim is to show that right-sided GP ablation which is known as cardioneuromodulation (CNM) is a new and promising way to cease recurrent syncope episodes and assess its effects on heart rate (HR), P-P intervals, ventricular depolarisation/repolarization parameters (QRS,QTc,Tpe durations, QTc/Tpe ratio), recurrence of syncope episodes, and patients symptoms such as fatigue, dizziness, etc. We also aimed to identify changes between pre and post procedural heart rates and its effects on short-term symptoms during follow-up. Methods A group of 55 patients with positive tilt table response or recurrent vasovagal syncope with pauses >2 sec in holter monitoring was enrolled this study. During the EP study, GPs determined both anatomically and by EP stimulation then autonomic denervation was performed focused by radiofrequency ablation. All patients followed-up for 12 months. Results Right-sided ablation was performed during the procedure and HR increased significantly in all patients after the procedure compared to before. Syncope episodes of the patients decreased significantly after the procedure. The patients who did not complain of syncope at the first, second and third appointment, respectively, 76.4% (n:42), 90.9% (n:50) and 92.7% (n:51). Patients had complaints at most within the first 4 months after the procedure (Table-1). At the first appointment, 4 (7.3%) patients had syncope and 9 (16,4%) patients had sinus tachycardia. Patient group with heart rate variability varying more or less than 20% during the procedure were examined, 81% of those with HR variability <20% did not have any symptoms, while 64.7% of the group with HR variability above 20% did not have any symptoms at first appointment (p:0,461) (Table.2). Tachycardia was seen in 23.5% of those with HR variability >20%, while it was determined as 9.5% in those with a HR variability <20 % Although these comparisons do not show a statistically significant difference due to the number of few patients, it is clinically significant. The same relationship was not observed between HR variability and symptoms in the second and third appointments. Conclusion Cardioneuromodulation is a remarkable treatment modality and it should be taken into consideration that more symptoms may develop in the early post-procedural period in the group who has post-procedure heart rate variability over 20%, and a cut-off should be determined for the target heart rate during the procedure.Table-1Table-2