Renal sympathetic denervation using an externally irrigated radiofrequency ablation catheter for treatment of resistant hypertension - Acute safety and short term efficacy.

OBJECTIVES: This study was conducted to assess the acute safety and short term efficacy of renal sympathetic denervation (RSDN) using solid tip radiofrequency ablation (RFA) catheter and saline irrigation through the renal guiding catheter to achieve effective denervation. BACKGROUND: RSDN using a specialized solid-tip RFA catheter has recently been demonstrated to safely reduce systemic blood pressure in patients with refractory hypertension, the limitation being inadequate power delivery in renal arteries. So, we used solid-tip RFA catheter along with saline irrigation for RSDN. METHODS: Nine patients with resistant hypertension underwent CT and conventional renal angiography, followed by bilateral or unilateral RSDN using 5F RFA catheter with saline irrigation through renal guiding catheter. Repeat renal angiography was performed at the end of the procedure. In all patients, pre- and post-procedure serum creatinine was measured. RESULTS: Over 1-month period: 1) the systolic/diastolic blood pressure decreased by -57 ± 20/-25 ± 7.5 mm Hg; 2) all patients experienced a decrease in systolic blood pressure of at least -36 mm Hg (range 36-98 mm Hg); 3) there was no evidence of renal artery injury immediate post-procedure. There was no significant change in serum creatinine level. CONCLUSIONS: This data shows the acute procedural safety and short term efficacy of RSDN using modified externally irrigated solid tip RFA catheter.

Renal denervation in a patient with Alport syndrome and rejected renal allograft.

Renal denervation is a new intervention to treat resistant hypertension. By applying radiofrequency (RF) to renal arteries, sympathetic nerves in adventitia layer of vascular wall can be denervated. Sympathetic hyperactivity is an important contributory factor in hypertension of hemodialysis patients. Hyperactive sympathetic nervous system aggravates hypertension and it can cause complications like left ventricular hypertrophy, heart failure, arrhythmias and atherogenesis. Our report illustrates the use of renal denervation using conventional RF catheter for uncontrolled hypertension in a patient with Alport syndrome and rejected renal allograft. Progressive and sustained reduction of blood pressure was obtained post-procedure and at 24 months follow-up with antihypertensives decreased from 6 to 2 per day, thereby demonstrating the safety, feasibility, and efficacy of the procedure. There are some reports available on the usefulness of this technique in hemodialysis patients; however, there are no studies of renal denervation in patients with Alport syndrome and failed allograft situation.