One-stop strategy for treatment of atrial fibrillation: feasibility and safety of combining catheter ablation and left atrial appendage closure in a single procedure / 中华医学杂志(英文版)

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.

Feasibility and perioperative safety of the combined procedure of catheter ablation and watchman left atrial appendage closure / 中华心血管病杂志

Objective: We aimed to explore the feasibility and perioperative safety of performing catheter ablation and left atrial appendage closure (LAAC) in a single (one-stop) session in patients with atrial fibrillation (AF). Methods: This study is an observational study. Consecutive AF patients who underwent the combined procedure of catheter ablation and LAAC with Watchman device of Xinhua Hospital in Shanghai between March 2017 and May 2019 were prospectively enrolled. Baseline, intra-and peri-procedural parameters were evaluated. Results: A total of 358 AF patients (189 males, (69.0±8.0) years) underwent the one-stop procedure. The CHA2DS2-VASc score was 3.2±1.5 and HAS-BLED score was 2.4±1.1, respectively in this patient cohort. Pulmonary vein isolation was achieved in all patients, while additional linear ablation was applied in 180 (50.3%) patients, yielding immediate success rate of 99.7%. Successful Watchman implantation was achieved in all patients. The perioperative serious adverse event occurred in 14 cases (3.9%). including 6 pericardial effusions (1.7%), 1 stroke (0.3%) and 5 vascular complications (1.4%), yielding procedure-related complication rate of 3.4%. In addition, 2 (0.6%) new-onset heart failures occurred postoperatively. There was no major bleeding or death during the perioperative period. Conclusions: Combined catheter ablation and LAAC can be successfully and safely performed in AF patients with high stroke risk. Follow-up data are needed to evaluate the outcome of this one-stop procedure.

A low-pass filter of 300 Hz improved the detection of pacemaker spike on remote and bedside electrocardiogram / 中华医学杂志(英文版)

BACKGROUND@#The current upper-frequency cutoff of 150 Hz sometimes causes loss of pacemaker spike and misdiagnosis. We hypothesized that low-pass filter (LPF) other than 150 Hz 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 patients' 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 300 Hz LPF also had a higher accuracy (AUC = 0.93; 95% CI = 0.84-1.00) than that at 150 Hz (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.

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 / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>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.</p><p><b>METHODS</b>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.</p><p><b>RESULTS</b>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 I group (94.7%, 94.1%, P > 0.05, vs. 2.8%, 6.3%, P > 0.05).</p><p><b>CONCLUSIONS</b>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.</p>

Pulmonary vein antrum isolation of pre-excited atrial fibrillation / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Pulmonary vein antrum isolation (PVAI) of pre-excited atrial fibrillation (AF) is controversial. This study aimed to observe the therapeutic effects of PVAI on pre-excited AF.</p><p><b>METHODS</b>Twenty-nine patients with pre-excited AF were prospectively divided into a PVAI group (group I, 19 cases) and a control group (group II, 10 cases). To each case in group I, PVAI was performed, and then electroanatomical mapping of accessory pathways (AP) and ablation were constructed on a three-dimensional (3D) map of the valve annulus. Only AP ablation was performed in each case of group II.</p><p><b>RESULTS</b>Of the 29 cases, three were found to have dual APs, two had intermittent APs, and the remaining 24 had single APs. All APs were successfully ablated after the procedure. There were no significant statistical differences in the AP procedure duration ((77.4 ± 21.3) minutes vs. (85.3 ± 13.1) minutes), the AP ablation time ((204 ± 34) seconds vs. (223 ± 62) seconds) and the AP X-ray exposure time ((18.6 ± 4.4) minutes vs. (19.1 ± 4.5) minutes) respectively between groups I and II. As compared with the control group (5 of 10 cases, 50%), the PVAI group had a significantly lower AF recurrence rate (2 of 19 cases, 11%; P < 0.05) during follow-up of (20.5 ± 10.0) months. All seven patients who recurred were successfully abolished by a second ablation.</p><p><b>CONCLUSIONS</b>In patients with pre-excited AF, PVAI is an effective therapeutic approach with a low AF recurrence rate. 3D electroanatomical maps of AP contributed to the high success rate of ablation without significantly prolonging of operational duration and X-ray exposure time.</p>

Screening of High-pyruvate-producing Strain Using by TTC-CaCO_3 Complexes Medium / 微生物学通报

It designs a way that can easily screen high-pyruvate-producing strain.It is a intelligently selected method which can highly improve the efficiency of strain screening.The principle can be described as the following:On the CaCO-3 medium,a transparent ring can be exhibited based on the reaction of PYR produced by the strain and CaCO-3 in the medium for pyruvate-calcium is a kind of soluble substance,it is obviously that the high-pyruvate-producing strain has a bigger dimension of the transparent ring.On the other hand,color reaction between TTC and ADH indicate the enzyme activities which have a proportional relation with color,our object strain is a weak-ADH-enzyme-activities type with a weak metabolic flux from PYR to alcohol.So the white color strain may be the right choice.