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Pulmonary vein (PV) isolation using balloon ablation was developed as a technique for patients with paroxysmal atrial fibrillation (PAF). While most studies examined cryoballoon ablation (CBA), there have also been many reports on hot balloon ablation (HBA). We aimed to evaluate the clinical characteristics and outcomes between HBA and CBA. In a total of 103 consecutive patients with PAF who underwent catheter ablation, 60 propensity score–matched (30 CBA and 30 HBA) patients were enrolled. The procedural differences and clinical outcomes between the two groups were analyzed. The requirement for additional touch-up ablation was more frequent in the left superior pulmonary vein (LSP) in the HBA group than in the CBA group. Pre-procedural computed tomography (CT) images showed that a thicker left pulmonary vein ridge and larger cross-sectional area of the LSPV were significantly associated with residual PV potentials after HBA. However, post-procedural CT images showed that PV stenosis (> 25%) was higher in the HBA group (33%) than in the CBA group (0%). PV stenosis after HBA was observed most frequently in the right superior PV (50%). The atrial fibrillation/atrial tachycardia–free survival rate during follow-up (365 ± 102 days) was similar between the two groups (CBA vs. HBA, 83% vs. 90%). Although both balloon modalities can relieve atrial arrhythmia after the procedure, careful attention is required during HBA procedures, especially for the right superior PV, to avoid PV stenosis.

A 59-year-old man had a witnessed collapse while driving a car. Approximately 10 min after the call to emergency services, paramedics arrived and initiated cardiopulmonary resuscitation. The first electrocardiogram (ECG) obtained by paramedics showed pulseless electrical activity. Review of his prehospital records documented that he experienced approximately 13 min of no flow or low flow before return of spontaneous circulation. On admission, he was still comatose with midrange dilated pupils. Electrocardiogram showed sinus rhythm, ST segment elevation in lead aVR, and ST segment depression in leads I, II, and V4-6. Coronary angiography showed 99% narrowing of the left main coronary artery (LMCA), but did not show any disease in the right coronary artery. A bare-metal stent was placed in the LMCA, and postdilated at 20 atmospheres. Immediately after return to the coronary care unit, therapeutic hypothermia was initiated. Hypothermia with a target temperature of 33.0 degrees C was maintained for 30 h. During this period, no significant hemodynamic instability occurred under intra-aortic balloon pumping (IABP) and intravenous catecholamines. Subsequently, he was slowly rewarmed at a rate of 0.3 degrees C/h up to 36.0 degrees C. Next day, the neurological condition improved and IABP was stopped. Creatine kinase increased to 2182 IU/l. Stent thrombosis did not occur despite the ad hoc loading of antiplatelet drugs. Follow-up echocardiography 9 days later showed mild hypokinesia of the anterior wall with an ejection fraction of 77%. He was discharged with no neurologic complications 18 days later.

Introduction: The aim of the present study was to investigate the impact of the time interval from collapse to return of spontaneous circulation (CPA-ROSC) in cardiac arrest patients and the types of patients who will benefit from therapeutic hypothermia. Methods: Four hundred witnessed adult comatose survivors of out-of-hospital cardiac arrest of cardiac etiology were enrolled in the study. The favorable neurological outcome was defined as category 1 or 2 on the five-point Pittsburgh cerebral performance scale at the time of hospital discharge. A matching process based on the propensity score was performed to equalize potential prognostic factors in the hypothermia and normothermia groups, and to formulate a balanced 1:1 matched cohort study. Results: The rate of favorable neurological outcome was higher (P < 0.05) in the hypothermia group (n = 110) than in the normothermia group in patients with CPA-ROSC of 15 to 20 minutes (64% vs. 17%), 20 to 25 minutes (70% vs. 8%), 25 to 30 minutes (50% vs. 7%), 35 to 40 minutes (27% vs. 0%) and 40 to 45 minutes (29% vs. 2%). A similar association was observed in a propensity-matched cohort, but the differences were not significant. There was no significant difference in the rate of favorable neurological outcome between the hypothermia-matched group and the normothermia-matched group. In the patients whose CPA-ROSC was greater than 15 minutes, however, the rate of favorable neurological outcome was higher in the hypothermia-matched group than in the normothermia-matched group (27% vs. 4%, P < 0.001). In multivariate analysis, the CPA-ROSC was an independent predictor of favorable neurological outcome (every 1 minute: odds ratio = 0.89, 95% confidence interval = 0.85 to 0.92, P < 0.001). Conclusions: The CPA-ROSC is an independent predictor of neurological outcome. Therapeutic hypothermia is more beneficial in comatose survivors of cardiac arrest with CPA-ROSC greater than 15 minutes.