Lesion characteristics created by bipolar radiofrequency ablation; right-vs. left-side of septum and epicardium vs. endocardium in the free wall

Figures

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  Fig. 1. Schematic representation of experimental preparation Panel A is an illustration of bipolar ablation for interventricular septum (IVS). The porcine myocardium was placed between the two inner plastic containers. Each inner container was filled with Tyrode's solution, circulated by a pump and temperature-controlled by a heater. Tyrode's solution also filled the space around the myocardium. This dual-bath experimental setting was designed to allow most RF current to pass through the myocardium. Two ablation catheters were placed on opposite surfaces of each porcine myocardium. Panel B is an illustration of bipolar ablation for left ventricular free wall (LVFW), and a plastic board was inserted into one of the inner plastic containers, facing the epicardial myocardium to mimic the pericardial space. See detailed description in the text.

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  Fig. 2. Methodology of the lesion measurement Panels A and B are illustrations of the non-transmural and transmural lesions created in the IVS and LVFW. Measured parameters (a)-(g) in these lesions are described in the illustrations. See detailed description in the text.

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  Fig. 3. Gross macroscopic examination of the lesions Fig. 3A has examples of non-transmural lesions created in the interventricular septum (IVS) (left column) and left ventricular free wall (LVFW) (right column). Upper panels are a left ventricular (LV) septal lesion in the IVS and an LV endocardial lesion in the LVFW. Lower panels are a right ventricular (RV) septal lesion in the IVS and an LV epicardial lesion in the LVFW. Middle panels are the IVS and LVFW lesions sectioned transmurally. Panel 3B is examples of transmural lesions created in the IVS and LVFW. The arrangement of the figures is the same as in Panel 3A. Measurement method in each parameter (a)-(g) are shown in Fig. 2 and the measured values are shown in each lesion in this Fig. 3AB. Each lesion is surrounded by small dots. Epicardial lesions in the LVFW are larger than those in others. See detailed description in the text.