Purpose: To investigate the effect of renal denervation (RDN) on blood pressure and renal function in refractory hypertension after renal artery recanalization and optimal medical therapy.
Methods: Ten patients (6 women; mean age 70.0±5.1 years) with an office systolic blood pressure >160 mmHg despite taking ≥3 antihypertensive drugs and uni- or bilateral renal artery stenting were treated with RDN. Radiofrequency (RF) energy was delivered to the native segment of the artery keeping a 5-mm safe distance from the stented segments. Standardized office (OBP) and ambulatory (ABP) blood pressure measurements, medication, and renal assessment, including renal duplex ultrasound and renal function, were determined at baseline and on follow-up to 12 months.
Results: OBP (systolic/diastolic) at baseline was 190.0±20.4 / 84.2±10.1 mmHg. It decreased to 171.1±28.7* / 82.2±8.7, 165.5±28.4(†) / 76.1±7.4, and 158.3±14.2(†) / 75.5±9.5(†) mmHg (*p<0.001; (†)p<0.01) at 3, 6, and 12 months after RDN, respectively. Average ABP (systolic/diastolic) after 6 and 12 months decreased by -7.6(‡) / -3.1 and -11.3(‡) / -5.1(‡) mmHg ((‡)p<0.05). There was no renal artery (re)stenosis, dissection, or aneurysm within 12 months. Creatinine, cystatin C, and glomerular filtration rate remained unchanged. Urine albumin excretion decreased in 4/10 patients. Renal resistive indices improved in native, but not in stented renal arteries within the follow-up period.
Conclusion: This proof-of-concept study demonstrates that RF-based RDN can be safely and effectively delivered in patients with resistant hypertension and previous renal artery stenting.