Irrigated tip catheters for radiofrequency ablation in ventricular tachycardia

Abstract

Radiofrequency (RF) ablation with irrigated tip catheters decreases the likelihood of thrombus and char formation and enables the creation of larger lesions. Due to the potential dramatic consequences, the prevention of thromboembolic events is of particular importance for left-sided procedures. Although acute success rates of ventricular tachycardia (VT) ablation are satisfactory, recurrence rate is high. Apart from the progress of the underlying disease, reconduction and the lack of effective transmural lesions play a major role for VT recurrences. This paper reviews principles of lesion formation with radiofrequency and the effect of tip irrigation as well as recent advances in new technology. Potential areas of further development of catheter technology might be the improvement of mapping by better substrate definition and resolution, the introduction of bipolar and multipolar ablation techniques into clinical routine, and the use of alternative sources of energy.

Figure 1

Phase sensitive inversion recovery (PSIR) late Gadolinium enhancement (LGE) images in short axis (a; c) and 4-chamber view orientation (b; d). The first row (a; b) shows the images before ablation of ventricular tachycardia and premature ventricular contractions at the midventricular lateral wall. There is a large area of fibrosis at the inferior and inferolateral wall (arrows) from previous ablation. Images 1 day after ablation (c; d) show small linear transmural LGE (arrowheads) which is interpreted as postablational necrosis.