One-stop strategy for treatment of atrial fibrillation:feasibility and safety of combining catheter ablation and left atrial appendage closure in a single procedure

Background:Catheter ablation is effective in restoring sinus rhythm and left atrial appendage closure(LAAC)is increasingly used for stroke prevention in patients with atrial fibrillation(AF).We aimed to observe the feasibility and safety of performing AF ablation and LAAC in a single(one-stop)procedure.Methods:Consecutive AF patients who underwent the combined procedure of AF ablation and LAAC with WATCHMAN device between March 2017 and September 2018 were prospectively enrolled.Baseline and intra-procedural parameters were evaluated.Three-month and subsequent 1-year follow-up were performed in all and earlier-enrolled subjects,respectively.Results:A total of 178 AF patients(94 males,68.9±8.1 years)underwent the one-stop procedure with CHA2DS2-VASc score 3.3±1.5 and HAS-BLED score 1.6±1.0,respectively.Pulmonary vein isolation was achieved in all patients while additional linear ablation was applied if the operator deemed necessary,yielding immediate ablation success rate of 98.9%(176/178).In the subsequent LAAC,satisfactory seal(residual leak<5 mm)was achieved in all patients.One stroke and four cardiac perforations occurred peri-operatively.At 3-month follow-up,sinus rhythm and satisfactory seal were maintained in 153/178(86.0%)and 178/178(100%)patients,respectively.One stroke and one delayed cardiac tamponade occurred,while no device-related thrombus or device migration was observed.During the 1-year follow-up for the earlier enrolled subjects,52/72(72.2%)of the patients maintained sinus rhythm.There was no stroke or systemic embolism observed.Conclusion:Combining catheter ablation and LAAC in a single procedure can be successfully and safely performed in non-valvular AF patients of Chinese population.

Adenosine Sensitivity is Associated with Ablation Success Rate and Recurrence Rate with Nonirrigated Catheters in Patients with Ventricular Premature Contractions/Tachycardia from the Ventricular Outflow Tract

Background：A high ablation success rate for ventricular arrhythmia （VA） from outflow tract has been achieved,but some of them cannot be eliminated from endocardium.We investigated the association between adenosine sensitivity and ablation success/recurrence rates with a nonirrigated or an irrigated catheter.Methods：According to adenosine test,all patients were divided into a sensitive group （S group） or an insensitive group （Ⅰ group）.The patients of each group were randomized into a nonirrigated catheter （NA） subgroup or an irrigated catheter （IA） subgroup with a 2∶1 ratio.Results：In S group of 122 patients （84 in NA subgroup）,the ablation success rate was similar between two subgroups （94.7% vs.90.5%,P 〉 0.05）,but in Ⅰ group of 94 patients （60 in NA subgroup）,it was higher in IA subgroup （94.1%） than that in NA subgroup （73.3%,P 〈 0.05）.The success rate using nonirrigated catheter was significantly higher in S group （90.5%） than that in Ⅰ group （73.3%,P 〈 0.01）,and the recurrence rate was lower in S group than that in Ⅰ group （1.3%,vs.13.6%,P 〈 0.05）.On the contrary,the success rate and the recurrence rate using irrigated catheter were similar between S group and 1 group （94.7%,94.1%,P 〉 0.05,vs.2.8%,6.3%,P 〉 0.05）.Conclusions：Adenosine insensitivity is associated with a lower success rate and a higher recurrence rate for VA patients undergoing nonirrigated catheter ablation.Thus,irrigated catheters should be the first choice for VA ablation in adenosine insensitive patients.

A low-pass filter of 300 Hz improved the detection of pacemaker spike on remote and bedside electrocardiogram

Background: The current upper-frequency cutoff of 150Hz sometimes causes loss of pacemaker spike and misdiagnosis, hypothesized that low-pass filter (LPF) other than 150Hz could improve the detection of pacemaker spike. This study aimed to examine the effect of different LPF on pacemaker spike detection in remote and bedside electrocardiogram (ECG). Methods: Patients with permanent pacemaker implantation were included during routine follow-up. Standard 12-lead ECGs at 6 different upper-frequency cutoff (40,100,150,200, 300, and 400 Hz) were collected. All ECGs were then transmitted to the remote clinic center. Ventricular and atrial pacing were analyzed by 2 independent medical practitioners. Results: A total of 88 patients5 ECGs were analyzed (mean age 73.8±10.2 years and 85 with dual-chamber pacemakers). About 75.3%(64/85) of patients were diagnosed as atrial pacing by pacemaker programming. Among 6 different upper-frequency cutoff, the 300 Hz turned out to perform best in detecting atrial-paced spike (area under the curve [AUC]=0.73, 95% confidence interval [CI]:0.61-0.84 vs.0.56, 95% CI: 0.61-0.84 at 150 Hz;P=0.002) on bedside ECGs. Using programming as the golden standard, the 300 Hz LPF has a sensitivity of 59.4%, specificity of 85.7%, positive predictive value of 92.7% and negative predictive value of 40.9% on bedside ECGs. As for the ventricular pacing, the 300Hz LPF also had a higher accuracy (AUC=0.93;95% CI = 0.84-1.00) than that at 150Hz (AUC = 0.86;95% CI:0.77-0.94;P<0.001) in detecting ventricular-paced spike on bedside ECGs. The results of remote ECGs were similar with bedside ECGs. Conclusions: A filter of 300 Hz cutoff may be recommended for ECG spike detection. With the recommended parameter, remote ECG can perform as well as bedside ECG.