Safety and Efficacy of Transvenous Lead Extraction With a High-Frequency Excimer Laser　- A Single Center Experience.

BACKGROUND: Transvenous lead extractions have been performed using 40-Hz laser sheaths. Recently, a new 80-Hz laser sheath became available, but only a few reports have compared the effectiveness of the 40- and 80-Hz laser sheaths. Methods and Results: This study included 215 patients. Lead extractions using only laser sheaths were analyzed. The clinical characteristics, extraction parameters, and extraction tools were evaluated. The procedures were performed with 40-Hz sheaths in 150 patients (group 1: 270 leads) and 80-Hz sheaths in 65 (group 2: 99 leads). No statistically significant differences were observed in the clinical parameters except for sex. The mean implant duration was 95.3±86.0 and 78.2±56.8 months in groups 1 and 2, respectively (P=0.07). The respective mean laser time and number of laser pulses were 48.5±52.1 and 48.1±56.1 s (P=0.96) and 2,035.0±2,384.0 and 3,955.1±2,339.3 pulses (P<0.0001). Complete removal was achieved for 97.4% of the leads and in 98.0% in both groups (P=0.38). Major complications occurred in 2.0% and 3.1% of the patients in groups 1 and 2, respectively (P=0.94). CONCLUSIONS: Transvenous lead extraction using high-frequency laser sheaths was as highly successful as with low-frequency laser sheaths in Japanese patients.

Life-Threatening Ventricular Arrhythmia and Brugada-Type ST-Segment Elevation Associated With Acute Ischemia of the Right Ventricular Outflow Tract.

BACKGROUND: Brugada-type ECG (Br-ECG) is occasionally observed during acute myocardial ischemia of the right ventricular outflow tract (RVOT). No studies have explored, however, the association of ventricular tachyarrhythmia and development of Br-ECG due to acute ischemia of the RVOT.Methods and Results:The study included 13 consecutive patients with acute ischemia of the RVOT during coronary catheterization. Patients were divided into 2 groups: those with Br-ECG (group B) and those without (group N). The proportion of male patients was higher in group B than in group N (100% vs. 25%, P<0.01), and VT/VF developed in only patients with Br-ECG (group B). In group B, VT/VF was observed in patients without pre-existing organic change in the conus/right ventricular (RV) branch of the right coronary artery and no VT/VF was seen in patients with organic coronary stenosis despite Br-ECG. CONCLUSIONS: Acute myocardial ischemia of the RVOT caused Br-ECG predominantly in male patients and subsequent development of VT/VF in some patients. VT/VF was seen in patients without any obstructive lesion but arrhythmic events were not observed in RVOT ischemia in the case of pre-existing coronary occlusion or stenosis of the conus or RV branch, suggesting the effects of precondition.