Electrophysiological mapping and ablation
A series of mapping and ablation parameters of successful ablated DGCV-AIV VAs by NS approach and by SS approach were also compared.There were no significant differences in the local ventricular activation time relative to the QRS onset (V-QRS), ventricular capture ratio, pace-match leads, procedure time, RF duration, numbers of RF lesions and fluoroscopy time. The operation time in coronary venous system by SS approach was slightly longer than by NS approach,shown inTable2 .
Complications during the procedure by NS approach and SS approach were also compared. There were no significant differences in occurrence of complications between these two groups (4/123, 3.25% vs 7/79, 8.86%, p>0.05). Via SS approach, coronary vein dissection happened on 3 patients and coronary vein rupture happened on 2 patient. The two patients of coronary vein rupture developed cardiac tamponade, but turned hemodynamic stable post emergent pericardiocentesis. One patient has severe chest pain with CAG showing an acute irreversible 50% coronary stenosis in LAD, another patient had an episode of chest tightness, and coronary angiography revealed coronary spasm of LCx, and relieved by intravenous nitroglycerin. By NS approach, coronary vein dissection happened on 2 patients and coronary vein rupture occurred on one patient. Coronary vein rupture caused delayed pericardial effusion but without unstable hemodynamics, thus pericardiocentesis was not performed. Coronary spasm occurred on 1 patient but relieved by intravenous nitroglycerin, shown in Table4 .