Interv Akut Kardiol. 2014;13(2):59-61

Vascular reaction after application of radiofrequency energy in renal arteries assessed by intravascular ultrasound

Michael Želízko¹, Vladimir Karmazín, Peterková Ludmila², Bronislav Janek, Vladimír Pořízka, Marek Hrnčárek

¹ Klinika kardiologie IKEM, Praha

² Pracoviště preventivní kardiologie IKEM, Praha

Purpose: The aim of the study was to evaluate the acute vascular changes after application of RF energy within the renal denervation

using intravascular ultrasound.

Methods: In 4 patients with resistant hypertension referred for renal sympathetic denervation selective angiography and intravascular

ultrasound examination (IVUS) was performed in total of 9 renal arteries before and after procedure.

Results: Angiographically the caliber of renal arteries in the entire length of the intervened segment decreased in total of 0.37 ± 0.14 mm (from

5.45 ± 1.14 mm to 5.08 ± 1.12 mm, p = 0.004). According to IVUS the vessel area did not change significantly (27.8 ± 10.2 vs 28.5 ± 11.0 mm2, p =

0.173). Minimal lumen area (MLA) was significantly reduced (23.5 ± 9.1 vs 21.4 ± 8.3 mm2, p = 0.004) as a result of thickening of the intima and

media layers (from 4.3 ± 1.8 mm2 to 7.1 ± 3.0 mm2, p = 0.004), which corresponds to the increase of the intima – media thickness from 0.24 mm to

0.40 mm (an increase of 66 % from baseline, p = 0.004). The uniform nature of the tissue on IVUS examination suggests edema of media layer.

Conclusion: Application of RF energy is accompanied by a certain degree of damage to the intima and media of the renal arteries. The external elastic

membrane remains seemingly undamaged and can be a natural barrier that protects sympathetic nerve fibers in the deeper layers from damage.

nervous system.

Keywords: intravascular ultrasound, radiofrequency ablation, renal angiography, renal denervation, resistant hypertension, sympathetic

Published: May 15, 2014  Show citation