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1.
Purpose

A significant proportion of patients undergoing catheter ablation for atrial fibrillation (AF) experience arrhythmia recurrence. This is mostly due to pulmonary vein reconnection (PVR). Whether mapping using High-Density Wave (HDW) technology is superior to standard bipolar (SB) configuration at detecting PVR is unknown. We aimed to evaluate the efficacy of HDW technology compared to SB mapping in identifying PVR.

Methods

High-Density (HD) multipolar Grid catheters were used to create left atrial geometries and voltage maps in 36 patients undergoing catheter ablation for AF (either due to recurrence of an atrial arrhythmia from previous AF ablation or de novo AF ablation). Nineteen SB maps were also created and compared. Ablation was performed until pulmonary vein isolation was achieved.

Results

Median time of mapping with HDW was 22.3 [IQR: 8.2] min. The number of points collected with HDW (13299.6±1362.8 vs 6952.8±841.9, p<0.001) and used (2337.3±158.0 vs 1727.5±163.8, p<0.001) was significantly higher compared to SB. Moreover, HDW was able to identify more sleeves (16 for right and 8 for left veins), where these were confirmed electrically silent by SB, with significantly increased PVR sleeve size as identified by HDW (p<0.001 for both right and left veins). Importantly, with the use of HDW, the ablation strategy changed in 23 patients (64% of targeted veins) with a significantly increased number of lesions required as compared to SB for right (p=0.005) and left veins (p=0.003).

Conclusion

HDW technology is superior to SB in detecting pulmonary vein reconnections. This could potentially result into a significant change in ablation strategy and possibly to increased success rate following pulmonary vein isolation.

  相似文献   
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Graefe's Archive for Clinical and Experimental Ophthalmology - Although latency has been cited as a disadvantage of the three-dimensional heads-up display (3D HUD) visualization system for...  相似文献   
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Myocardial injury due to ischaemia within 30 days of non-cardiac surgery is prognostically relevant. We aimed to determine the discrimination, calibration, accuracy, sensitivity and specificity of single-layer and multiple-layer neural networks for myocardial injury and death within 30 postoperative days. We analysed data from 24,589 participants in the Vascular Events in Non-cardiac Surgery Patients Cohort Evaluation study. Validation was performed on a randomly selected subset of the study population. Discrimination for myocardial injury by single-layer vs. multiple-layer models generated areas (95%CI) under the receiver operating characteristic curve of: 0.70 (0.69–0.72) vs. 0.71 (0.70–0.73) with variables available before surgical referral, p < 0.001; 0.73 (0.72–0.75) vs. 0.75 (0.74–0.76) with additional variables available on admission, but before surgery, p < 0.001; and 0.76 (0.75–0.77) vs. 0.77 (0.76–0.78) with the addition of subsequent variables, p < 0.001. Discrimination for death by single-layer vs. multiple-layer models generated areas (95%CI) under the receiver operating characteristic curve of: 0.71 (0.66–0.76) vs. 0.74 (0.71–0.77) with variables available before surgical referral, p = 0.04; 0.78 (0.73–0.82) vs. 0.83 (0.79–0.86) with additional variables available on admission but before surgery, p = 0.01; and 0.87 (0.83–0.89) vs. 0.87 (0.85–0.90) with the addition of subsequent variables, p = 0.52. The accuracy of the multiple-layer model for myocardial injury and death with all variables was 70% and 89%, respectively.  相似文献   
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Background

Persistent iatrogenic atrial septal defect (iASD) is a common but poorly characterized complication after cryoballoon (CB) pulmonary vein isolation (PVI) procedures. We therefore investigate its prevalence, evolution, risk factors, and clinical outcomes in a prospective longitudinal study.

Methods

A total of 108 patients (41 women, mean age 57 ± 11.3) underwent CB PVI for AF. Serial transesophageal echocardiography (TEE) was performed 9 months and then annually until 6 years after the procedure to study the characteristics of persistent iASD.

Results

Persistent iASD occurred in 33 (30.6%) patients 9 months after CB PVI. Spontaneous closure of iASD was found in 6 (22.2%) and 3 (15.8%) patients 2 and 3 years after the procedures, respectively. No spontaneous closure was observed on 4, 5, and 6-year TEE follow-up. The projected long-term persistence rate of iASD after CB PVI was therefore 20% (30.6% × 0.778 × 0.842). Using multivariate logistic regression, a higher number of cryoapplications (≥ 2 minutes) was the only independent predictor of persistent iASD 9 months after CB PVI (odds ratio [OR] 1.207; 95% confidence interval [CI], 1.033-1.411, P = 0.018). Two (1.9%) patients with significantly larger iASD size than the others (long diameter 12.6 ± 0.8 vs 3.7 ± 1.5 mm, P < 0.001; short diameter 10.9 ± 0.2 vs 3 ± 1.1 mm, P < 0.001) required percutaneous closure because of exertional dyspnea and right ventricular enlargement. Over 129.7 patient-years follow-up, during which iASD persisted, there was no occurrence of neurologic events.

Conclusions

Approximately one fifth of patients undergoing CB PVI will have permanently persistent iASD. Patients with defect sizes of greater than 10 mm may need percutaneous closure due to significant left-to-right shunting.  相似文献   
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