Cardiology Department Westmead Hospital Sydney NSW Australia.
Westmead Applied Research Centre University of Sydney NSW Australia.
J Am Heart Assoc. 2024 May 7;13(9):e031795. doi: 10.1161/JAHA.123.031795. Epub 2024 Apr 25.
Transcatheter renal denervation (RDN) has had inconsistent efficacy and concerns for durability of denervation. We aimed to investigate long-term safety and efficacy of transcatheter microwave RDN in vivo in normotensive sheep in comparison to conventional radiofrequency ablation.
Sheep underwent bilateral RDN, receiving 1 to 2 microwave ablations (maximum power of 80-120 W for 240 s-480 s) and 12 to 16 radiofrequency ablations (180 s-240 s) in the main renal artery in a paired fashion, alternating the side of treatment, euthanized at 2 weeks (acute N=15) or 5.5 months (chronic N=15), and compared with undenervated controls (N=4). Microwave RDN produced substantial circumferential perivascular injury compared with radiofrequency at both 2 weeks [area 239.8 (interquartile range [IQR] 152.0-343.4) mm versus 50.1 (IQR, 32.0-74.6) mm, <0.001; depth 16.4 (IQR, 13.9-18.9) mm versus 7.5 (IQR, 6.0-8.9) mm <0.001] and 5.5 months [area 20.0 (IQR, 3.4-31.8) mm versus 5.0 (IQR, 1.4-7.3) mm, =0.025; depth 5.9 (IQR, 1.9-8.8) mm versus 3.1 (IQR, 1.2-4.1) mm, =0.005] using mixed models. Renal denervation resulted in significant long-term reductions in viability of renal sympathetic nerves [58.9% reduction with microwave (=0.01) and 45% reduction with radiofrequency (=0.017)] and median cortical norepinephrine levels [71% reduction with microwave ( <0.001) and 72.9% reduction with radiofrequency ( <0.001)] at 5.5 months compared with undenervated controls.
Transcatheter microwave RDN produces deep circumferential perivascular ablations without significant arterial injury to provide effective and durable RDN at 5.5 months compared with radiofrequency RDN.
经导管肾去神经（RDN）的疗效不一致，且存在去神经支配的持久性问题。我们旨在研究在正常血压绵羊体内经导管微波 RDN 的长期安全性和疗效，并与传统射频消融进行比较。
绵羊接受双侧 RDN，以配对方式在主肾动脉中接受 1 至 2 次微波消融（最大功率 80-120W，持续 240-480s）和 12 至 16 次射频消融（180-240s），交替治疗侧，在 2 周（急性，N=15）或 5.5 个月（慢性，N=15）时安乐死，并与未去神经对照（N=4）进行比较。微波 RDN 与射频相比，在 2 周时产生了广泛的血管周围损伤[面积 239.8（四分位距[IQR] 152.0-343.4）mm 比 50.1（IQR，32.0-74.6）mm， <0.001；深度 16.4（IQR，13.9-18.9）mm 比 7.5（IQR，6.0-8.9）mm， <0.001]和 5.5 个月时[面积 20.0（IQR，3.4-31.8）mm 比 5.0（IQR，1.4-7.3）mm，=0.025；深度 5.9（IQR，1.9-8.8）mm 比 3.1（IQR，1.2-4.1）mm，=0.005]，采用混合模型。肾去神经支配导致肾交感神经的长期生存能力显著降低[微波治疗组降低 58.9%（=0.01），射频治疗组降低 45%（=0.017）]和皮质去甲肾上腺素水平中位数降低[微波治疗组降低 71%（ <0.001），射频治疗组降低 72.9%（ <0.001）]，与未去神经对照组相比，在 5.5 个月时。
与射频 RDN 相比，经导管微波 RDN 可产生深部环形血管周围消融，而不会对动脉造成显著损伤，可在 5.5 个月时提供有效且持久的 RDN。
