Effect of radiofrequency catheter ablation on calcium channel of ventricular myocytes

Abstract

Using whole-cell patch-clamp technique, the effect of radiofrequency catheter ablation (RFCA) on calcium current (Ic_a) of guinea pig ventricular myocytes was examined. The radiofrequency energy delivered was 20 W× 10 s. RFCA decreased Ic_a apparently with the affected area reaching up to 1.2 cm from the ablation focus. In the meanwhile, the pathological lesion size resulted from RFCA was merely 0. 41 ±0. 11 cm. These findings indicate that RFCA, apart from causing tissue necrosis by heat, can affect myocyte membrane currents in a large area. This may explain why RFCA has a very high success rate with a small pathological lesion.

Keywords

patch-clamp / arrhythmia / ablation / radiofrequency / ion channel

References

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