Treatment, follow-up and results of parallel group studies of renal denervation versus control in resistant hypertension
| Clinical trials | RD group | Control group | Duration of follow-up | Efficacy results |
|---|---|---|---|---|
| Pokushalov et al12 | RFA of 8–10 W for 2 min up to 6 lesions and pulmonary vein isolation | Pulmonary vein isolation alone | 12 months | Reduction at 6 months Systolic BP Denervation: −28±7 mm Hg Control: −5±5 mm Hg |
| Diastolic BP: Denervation: −10±6 mm Hg Control: −3±6 mm Hg | ||||
| SYMPLICITY HTN-27 | Catheter-based RD with SYMPLICITY Catheter System | Continuation of anti-hypertensive drugs | 1, 3 and 6 months | Systolic BP RD group (n=52): Baseline 178±18/96±16 mm Hg. Change at 1 months −20, 3 months −24, 6 months −32±23 mm Hg. Control group (n=54): Baseline mm Hg. Change at 1 months 0, 3 months −4, 6 months 1±21 mm Hg |
| Diastolic BP RD group (n=52): Baseline 178±17/98±16 mm Hg. Change at 1 months −7, 3 months −8, 6 months −12±11 mm Hg. Control group (n=54): Baseline mm Hg. Change at 1 months 0, 3 months −2, 6 months 0±10 mm Hg | ||||
| SYMPLICITY HTN-38 9 | Catheter-based RD with SYMPLICITY Catheter System | Sham procedure | 1, 6 months | Systolic BP RD group (n=364): Baseline office 179.7±16.1. Value at 6 months: 165.6±23.7. Change from baseline:−14.13±23.93 mm Hg Baseline ambulatory: 159.1±13.2. Value at 6 months: 151.8±16.0. Baseline home: 169.0±15.9. Value at 6 months: 161.1±19.2. Control group (n=171): Baseline office 180.2±16.8. Value at 6 months: 168.4±28.6. Change from baseline −11.74±25.94 mm Hg Baseline ambulatory: 159.5±13.5. Value at 6 months: 153.9±19.1. Baseline home: 169.1±16.3. Value at 6 months: 162.8±21.1 |
| Diastolic BP RD group (n=364): Baseline office 96.5±16.6. Value at 6 months: 89.5±16.9 Change from baseline −6.75±15.11 mm Hg Baseline ambulatory:88.0±14.0. Value at 6 months: 83.1±13.7. Baseline home: 89.6±15.9. Value at 6 months: 86.0±16.6. Control group (n=171): Baseline office 98.9±15.8. Value at 6 months: 94.1±17.7 Change from baseline −4.79±17.25 mm Hg. Baseline ambulatory: 90.9±14.4. Value at 6 months: 87.4±14.6. Baseline home: 92.9±16.4. Value at 6 months: 90.0±16.4 | ||||
| Observational studies | ||||
| Brandt et al14 | RD with SYMPLICITY or Flex catheter (Ardian) with up to 6 ablations at 8 W for 2 min each were performed for both renal arteries | Details of control group not specified | 1 and 6 months | Resting systolic BP RD group (n=46): Baseline 180.7±18.3, 1 month 158.2±17.6, 6 months 152.9±22.4 mm Hg. Control group (n=18): Baseline 184.5±22.1, 1 month 181.6±26.3, 6 months 182.8±24.6 mm Hg. Resting diastolic BP RD group (n=46): Baseline 95.8±10.1, 1 month 88.6±10.9, 6 months 87±12.9 mm Hg. Control group (n=18): Baseline 98.2±13.6, 1 month 98±12.7, 6 months 99.8±16.5 mm Hg. The average number of antihypertensives was constant for control group 4.8±2.5 while in RD group it deceased in seven patients (15%) which led to a change from 4.7±0.5 to 4.5±1.6 antihypertensives |
| Brandt et al15 | RD with catheter (SYMPLICITY and Flex by Ardian) with up to 6 ablations at 8 W for 2 min each were performed for both renal arteries | Details of control group not specified | 1, 3 and 6 months | Resting systolic BP RD group (n=110): Baseline 181±24.7, 1 month 161.1±22.8, 3 month 159.1±22.1, 6 months 152.1±20 mm Hg. Control group (n=10): Baseline 183.9±21.6, 1 month 181.3±18.5, 3 month 190.6±16.9, 6 months 193.9±15.4 mm Hg. Resting diastolic BP RD group (n=110): Baseline 91.4±12.8, 1 month 87±14, 3 months 84±13.1, 6 months 83.7±13.5 mm Hg. Control group (n=10): Baseline 95.3±11.5, 1 month 97.1±18.9, 3 months 104.6±15.6, 101.5±17.9 mm Hg |
| Fatum et al16 | Catheter-based bilateral RD | Untreated controls | 6 months | At 6 months, office BP reduced by −26/−7 mm Hg in the RD group (n=15) and no significant changes in the control group (n=6). Baseline 170/89 mm Hg for RD group and 172/93 mm Hg for control group |
| Franzen et al13 | Percutaneous RD with a RFA catheter system | Details of control group not specified | 3 and 6 months | Systolic BP RD group (n=21): Baseline 156±13, 3 months 145±13, 6 months 148±17 mm Hg. Control group (n=6): Values did not change significantly |
| Krum et al6 | RD with catheter (SYMPLICITY) with ablations at 8 W for 2 min each were performed for both renal arteries | Patients with renovascular abnormalities such as severe renal artery stenosis, previous renal stenting/ angioplasty or known dual renal arteries | 1, 3, 6, 9 and 12 months | Mean reduction in office blood pressures for treatment group were −14/−10 (95% CI 4/3), −21/−10 (7/4), −22/−11 (10/5), −24/−11 (9/5) and −27/−17 at 1, 3, 6, 9 and 12 months. Mean reduction in office blood pressures were +3/−2, +2/+3, +14/+9, +26/+17 at 1, 3, 6 and 9. At baseline average of 4.7 hypertensive medications and 96% had diuretics. This did not change at follow-up |
| Lambert et al20 | Bilateral renal nerve ablation by a radiofrequency catheter (SYMPLICITY by Ardian) | Matched normotensive and controlled blood pressure controls from the Australian Diabetes, Obesity, and Lifestyle database | 3 months | Post RD BP had reduced by −16±4 and −6±2 mm Hg. Baseline BP was 166±3 and 88±2 mm Hg in RD group (n=62) |
| Mahfoud et al17 | Treatment catheter (SYMPLICITY and Flex by Ardian) with RFA lasting up to 2 min with low power of 8 W to obtain up to 6 ablations | Medical therapy | 1 and 3 months | Systolic BP RD group (n=37): Baseline 177±3.Change at 1 month −28±2, 3 months −32±4 mm Hg. Control group (n=13): Baseline 184±5. Change at 1 month −8±6, 3 months −5±5 mm Hg. Diastolic BP RD group (n=37): Baseline 96±6. Change at 1 month −10±2, 3 months −12±2 mm Hg. Control group (n=13): Baseline 94±4. Change at 1 month −4±4, 3 months −3±3 mm Hg. While patients were instructed not to change their medications, 13 patients in the treated group had to reduce antihypertensives because of symptoms of hypotension |
| Mahfoud et al18 | Treatment catheter (SYMPLICITY and Flex by Ardian) with ablations in both renal arteries with up to 8 ablations for 2 min with a maximum of 8 W | Details of control group not specified | 3 and 6 months | Systolic BP RD group (n=88): Baseline 174±2 mm Hg. Change at 3 month −22.7±2.3, 6 months −26.6±2.5 mm Hg. Control group (n=12): Baseline 184±7 mm Hg. Change at 3 month −7.2±7.6, 6 months −4.4±6.2 mm Hg. Diastolic BP RD group (n=88): Baseline 95±2 mm Hg. Change at 3 month −7.7±1.3, 6 months −9.7±1.5 mm Hg. Control group (n=12): Baseline 97±5 mm Hg. Change at 3 month −4.1±4.7, 6 months −3.0±4.3 mm Hg. Number of antihypertensives was 5.7±0.2. At 3 months follow-up 18 patients (18%) had reduced antihypertensives use and 7 (7%) had increased antihypertensive use |
| Ukena et al19 | Catheter-based RD with SYMPLICITY Catheter System | Details of control group not specified | 3 months | Systolic BP RD group (n=37): Baseline 172±24, 3 months 141±21 mm Hg. Change at 3 months 31±13 mm Hg. Control group (n=9): Baseline 166±23, 3 months 166±25 mm Hg. Change at 3 months 0±17 mm Hg. Diastolic BP RD group (n=37): Baseline 94±19, 3 months 85±16 mm Hg. Change at 3 months: −9±13 mm Hg. Control group (n=9): Baseline 90±7, 3 months 89±9 mm Hg. Change at 3 months −1±5 mm Hg |
BP, blood pressure; RD, renal denervation; RFA, radiofrequency ablation.