How does successful off-pump pulmonary vein isolation for paroxysmal atrial fibrillation influence heart rate variability and autonomic activity?

OBJECTIVE: : Surgical pulmonary vein isolation (PVI) for paroxysmal atrial fibrillation (PAF) blocks trigger stimulation from PVs and partially disconnects the atria from sympathetic and parasympathetic neural stimulation. This study describes long-term changes in heart rate variability (HRV) and autonomic activity (AA) after successful bipolar radiofrequency PVI. METHODS: : Twenty-seven patients who underwent coronary artery bypass grafting and successful (defined as stable sinus rhythm for 1 year) off-pump bipolar radiofrequency PVI for PAF were prospectively followed 3, 6, and 12 months after surgery including 24 hours Holter electrocardiogram. The following HRV and AA parameters were calculated: mean NN-interval, SD of NN-intervals, SD of averaged NN-intervals, root mean square of successive differences, low frequency (LF) power (0.04-0.15 Hz; a parameter specific for sympathetic activity), high frequency (HF) power (0.15-0.4 Hz; a parameter specific for parasympathetic activity), and the LF:HF ratio. RESULTS: : Preoperatively, high HRV and AA parameters were recorded. In 3-, 6-, and 12-month time, a progressive reduction of HRV and AA was observed, reaching significance after 12 months. Respective rates before surgery and 12 months after it were: for SD of averaged NN-intervals (122.4 ± 113; 80.5 ± 42 milliseconds; P = 0.046), for root mean square of successive differences (79.2 ± 93; 45 ± 20 milliseconds; P = 0.04). The LF:HF ratios were 1.22 and 0.73 before and 12 months after surgery, respectively. The statistically significant continuous reduction in LF:HF ratio (P = 0.02) is suggestive of a progressive parasympathetic dominance 12 months after surgery. CONCLUSIONS: : Successful PVI for PAF results in HRV and sympathetic activity reduction with preoperative sympathetic dominance and oncoming vagal dominance after 1 year from surgery. Despite preoperative sympathetic dominance, successful PVI for PAF results in HRV and a reduction in sympathetic activity with emerging parasympathetic dominance 12 months after surgery.

Minimally invasive off-pump video-assisted endoscopic surgical pulmonary vein isolation using bipolar radiofrequency ablation - preliminary report.

BACKGROUND: Atrial fibrillation (AF) is the most common arrhythmia, having a strong impact on long-term stroke and heart failure prevalence and mortality. Nowadays, rapid development in the field of minimising the invasiveness of surgical ablation of AF can be observed. AIM: To report on the feasibility and early results of the first Polish experience with a novel technique of minimally invasive video-assisted beating heart bilateral surgical ablation for lone paroxysmal AF using irrigated bipolar radiofrequency technique. METHODS: Between February and December 2006, 6 patients with highly symptomatic paroxysmal AF, resistant to pharmacological treatment, underwent video-assisted beating heart bilateral pulmonary vein isolation using irrigated bipolar radiofrequency combined with vein of Marshall dissection and left atrial appendage closure. In 2 patients at least 2 unsuccessful percutaenous ablations had previously been performed. RESULTS: There were no complications. Ablation time was on average 88+/-12.1 seconds. At least one recurrence of AF was observed in 4 patients in the early postoperative period; in 3 of them an electrical cardioversion was performed. All patients were discharged home in stable sinus rhythm. Three patients have exceeded 3 months' observation; one has reached 6 months of observation. All are in stable sinus rhythm and the follow-up course is uneventful. CONCLUSIONS: Minimally invasive video-assisted beating heart bilateral surgical ablation for lone paroxysmal AF using irrigated bipolar radiofrequency is effective and safe. These promising results have to be confirmed by larger studies.

Use of new liquid nitrogen cryocatheter in the surgical treatment of atrial fibrillation: clinical experience, mid- and long-term results.

Surgical treatment of atrial fibrillation (AF) evolves to less invasive, safer and technically easier procedures mostly due to the electrophysiological studies, technological progress and creativeness in ablation systems construction. We present first clinical experience, mid- and long-term results of AF treatment with new liquid nitrogen cryothermy device for endocardial application. In 26 patients we have proved the feasibility and clinical effectiveness of liquid nitrogen cryocatheter ablation reaching more than 70% of sinus rhythm rate in long follow-up from 3 up to 24 months.