Feasibility of catheter ablation renal denervation in "mild" resistant hypertension.

Renal denervation (RDN) has been proposed as a novel interventional antihypertensive technique. However, existing evidence was mainly from patients with severe resistant hypertension. The authors aimed to evaluate the efficacy of RDN in patients with resistant hypertension with mildly elevated blood pressure (BP). Studies of RDN in patients with mild resistant hypertension (systolic office BP 140-160 mm Hg despite treatment with three antihypertensive drugs including one diuretic, or mean systolic BP by 24-hour ambulatory BP measurement [ABPM] 135-150 mm Hg) were included. Two observational and one randomized cohort were identified (109 patients in the RDN group and 36 patients in the control group). Overall, the mean age of patients was 62±10 years, and 69.7% were male. Before-after comparison showed that RDN significantly reduced ABPM as compared with the baseline systolic ABPM, from 146.3±13 mm Hg at baseline to 134.6±14.7 mm Hg at 6-month follow-up and diastolic ABPM from 80.8±9.4 mm Hg at baseline to 75.5±9.8 mm Hg at 6-month follow up (both P<.001). This significant effect was not observed in the control group. Between-group comparison showed a greater change in ABPM in the RDN group as compared with that in the control group (change in systolic ABPM: -11.7±9.9 mm Hg in RDN vs -3.5±9.6 mm Hg in controls [P<.001]; change in diastolic ABPM: -5.3±6.3 mm Hg in RDN vs -2.1±5.5 mm Hg in control [P=.007]). RDN was also associated with a significantly decreased office systolic/diastolic BP and reduced number of antihypertensive medications. No severe adverse events were found during follow-up. RDN seems feasible to treat patients with mild resistant hypertension.

The addition of renal sympathetic denervation to pulmonary vein isolation reduces recurrence of paroxysmal atrial fibrillation in chronic kidney disease patients.

BACKGROUND: Atrial fibrillation (AF) frequently complicates chronic kidney disease (CKD). AF treatment is challenging and requires complete pulmonary vein isolation (PVI). Recently, renal sympathetic denervation (RSD) has been reported to reduce AF recurrence when performed alongside PVI. METHODS: A prospective therapeutic study of patients with controlled hypertension and paroxysmal AF was undertaken. Renal function was evaluated using estimated glomerular filtration rate. Outcomes for patients with normal renal function who underwent PVI (n = 101) were compared with those for CKD patients who underwent either PVI alone (n = 96) or PVI + RSD (n = 39). The primary endpoint was recurrence of AF recorded by 24-h Holter monitoring. RESULTS: During the 22.4 ± 12.1 months following intervention, the incidence of AF recurrence was higher in CKD patients treated with PVI alone (61.5 %) than in CKD patients treated with PVI + RSD (38.5 %; HR 1.86, 95 % CI 1.14-3.03, P = 0.0251) or patients without CKD subjected to PVI (35.6 %; hazard ratio (HR) 2.27, 95 % confidence interval (CI) 1.51-3.42, P < 0.0001). In particular, the addition of RSD to PVI significantly reduced AF recurrence in CKD stage 4, but not stage 2 or 3, patients. Ambulatory blood pressure and mean heart rate were not different between groups or time points. No complications of either procedure were observed. CONCLUSIONS: PVI + RSD is a safe treatment that is superior to PVI alone for treatment of paroxysmal AF in CKD patients.

Pulmonary vein isolation alone and combined with renal sympathetic denervation in chronic kidney disease patients with refractory atrial fibrillation.

BACKGROUND: Atrial fibrillation (AF) commonly occurs in association with chronic kidney disease (CKD), resulting in adverse outcomes. Combining pulmonary vein isolation (PVI) and renal sympathetic denervation (RSD) may reduce the recurrence of AF in patients with CKD and hypertension. We considered that RSD could reduce the recurrence of AF in patients with CKD by modulating sympathetic hyperactivity. Our goal was to compare the impact of PVI + RSD with that of PVI alone in patients with concurrent AF and CKD. METHODS: This was a single-center, prospective, longitudinal, randomized, double-blind study. Forty-five patients with controlled hypertension, symptomatic paroxysmal AF and/or persistent AF, stage 2 or 3 CKD, and a dual-chamber pacemaker were enrolled from January 2014 to January 2015. We assessed the 30-second recurrence of AF recorded by the pacemaker, 24-hour ambulatory blood pressure measurements, estimated glomerular filtration rate, albuminuria, echocardiographic parameters, and safety of RSD. RESULTS: No patient developed procedural or other complications. The ambulatory blood pressure measurements did not differ within the PVI + RSD group or between the PVI + RSD and PVI groups throughout the study. Significantly more patients in the PVI + RSD group than in the PVI group were free of AF at the 12-month follow-up evaluation. The PVI group had an unacceptable response to ablation with respect to changes in echocardiographic parameters, whereas these parameters improved in the PVI + RSD group. CONCLUSION: PVI + RSD were associated with a lower AF recurrence rate than PVI alone; it also improved renal function and some echocardiographic parameters. These encouraging data will serve as baseline information for further long-term studies on larger patient populations.

Proof of concept study: Improvement of echocardiographic parameters after renal sympathetic denervation in CKD refractory hypertensive patients.

AIM: Evaluation of the effectiveness of the renal sympathetic denervation (RSD) in reducing lesions of target organs such as the heart and kidneys, in resistant hypertensive CKD patients. METHODS AND RESULTS: Forty-five patients were included and treated with an ablation catheter with open irrigated tip. RSD was performed by a single operator following the standard technique. Patients included with CKD were on stages 2 (n=22), 3 (n=16), and 4 (n=7). Data were obtained at baseline and monthly until the 6th month of follow-up. Twenty-six out of the 45 patients had LVH and nineteen did not present LVH. The LV mass index decreased from 123.70±38.44g/m(2) at baseline to 106.50±31.88g/m(2) at the 6th month after RSD, P<0.0001. The end-diastolic left ventricular internal dimension (LVIDd) reduced from 53.02±6.59mm at baseline to 51.11±5.85mm 6months post procedure, P<0.0001. The left ventricular end-diastolic posterior wall thickness (PWTd) showed a reduction from 10.58±1.39mm at baseline to 9.82±1.15mm at the 6th month of follow-up, P<0.0001. The end-diastolic interventricular septum thickness (IVSTd) also decreased from 10.58±1.39mm at baseline to 9.82±1.15mm 6months post procedure, P<0.0001. The left ventricular ejection fraction (LVEF) improved from 58.90±10.48% at baseline to 62.24±10.50% at the 6th month of follow-up, P<0.0001. When the ∆ between baseline and the 6th month post RSD in LVH patients and non LVH patients were compared to the same parameters no significant difference was found. CONCLUSIONS: The RSD seemed to be feasible, effective, and safe resulting in an improvement of echocardiographic parameters in LVH and non LVH CKD refractory hypertensive patients.

Long-Term Effects of Renal Sympathetic Denervation on Hypertensive Patients With Mild to Moderate Chronic Kidney Disease.

Thirty patients who underwent percutaneous renal denervation, which was performed by a single operator following the standard technique, were enrolled in this study. Patients with chronic kidney disease (CKD) stage 2 (n=19), 3 (n=6), and 4 (n=5) were included. Data were obtained at baseline and at monthly intervals for the first 6 months. At 7 months, follow-up data were collected bimonthly until month 12, after which data were collected on a quarterly basis. Baseline blood pressure values (mean±standard deviation) were 185±18/107±13 mm Hg in the office and 152±17/93±11 mm Hg through 24-hour ambulatory blood pressure monitoring (ABPM). Three patients with stage 4 CKD required chronic renal replacement therapy (one at the 13-month follow-up and two at the 14-month follow-up) after episodes of acute renal injury; their follow-up was subsequently discontinued. The office blood pressure values at the 24-month follow-up were 131±15/87±9 mm Hg (P<.0001, for both comparisons); the corresponding ABPM values were 132±14/84±12 mm Hg (P<.0001, for both comparisons). The mean estimated glomerular filtration rate increased from 61.9±23.9 mL/min/1.73 m(2) to 88.0±39.8 mL/min/1.73 m(2) (P<.0001). The urine albumin:creatinine ratio decreased from 99.8 mg/g (interquartile range, 38.0-192.1) to 11.0 mg/g (interquartile range, 4.1-28.1; P<.0001 mg/g). At the end of the follow-up period, 21 patients (70% of the initial sample) were no longer classified as having CKD.

Case Report: Renal Sympathetic Denervation as a Tool for the Treatment of Refractory Inappropriate Sinus Tachycardia.

Inappropriate sinus tachycardia is defined as sinus tachycardia at rest (heart rate ≥100 bpm) in sitting position or/and as an average heart rate ≥90 bpm during 24-hour Holter monitoring. The most common symptoms are palpitation, dizziness, chest discomfort, orthostatic intolerance, and fatigue. Sometimes, the symptoms can be severe and debilitating, and its etiology is not well understood. Pharmacological approaches present limitation because of their relatively small effectiveness, intolerance, or side effects.In this series of cases of inappropriate sinus tachycardia, the authors report 3 cases refractory to conventional pharmacological therapy, in which the authors were not tempted for ablation of the sinus node. The authors, however, use another therapeutic approach, which was renal sympathetic denervation, to reduce sympathetic activity in the sinus node, and consequently reduce tachycardia with improvement of symptoms.Three months after renal sympathetic denervation, all patients were not using any type of medication, and reported no more symptoms. The authors know that this is the first report using the renal sympathetic denervation for the treatment of inappropriate sinus tachycardia. Studies with a larger number of patients, a longer time of follow-up, and a control group, however, should be performed.

Renal sympathetic denervation in patients with hypertension and chronic kidney disease: does improvement in renal function follow blood pressure control?

Twenty-seven patients with resistant hypertension and chronic kidney disease were treated by renal sympathetic denervation (RSD) and followed for 12 months. Patients were retrospectively divided into controlled and uncontrolled blood pressure (BP) groups. Increases in mean estimated glomerular filtration rate (eGFR) were found at months 1, 3, 6, and 12 in the controlled group (P < .0001, for every time point). The mean change in eGFR after 12 months was 18.54 ± 8.15 mL/min/1.73 m(2) higher in the controlled group (P=.0318). In patients in the controlled group with baseline eGFR < 45 mL/min/1.73 m(2), responders (with an increase in eGFR > 6.2%) corresponded to 50% at 6 months and 83% at 12 months. In the patients with baseline eGFR ≥ 45 mL/min/1.73 m(2), all patients were labeled as responders at months 6 and 12. Median albumin:creatinine ratio after 12 months was lower than baseline only in the controlled group (P = .0003). Our results suggest that patients with this profile who reached BP control by RSD also experienced a significant improvement in renal function.

Effects of renal denervation with a standard irrigated cardiac ablation catheter on blood pressure and renal function in patients with chronic kidney disease and resistant hypertension.

AIMS: Evaluation of the safety and efficacy of renal denervation with a standard irrigated cardiac ablation catheter (SICAC) in chronic kidney disease (CKD) patients with refractory hypertension. METHODS AND RESULTS: Twenty-four patients were included and treated with a SICAC. Denervation was performed by a single operator following the standard technique. Patients included with CKD were on stages 2 (n = 16), 3 (n = 4), and 4 (n = 4). Data were obtained at baseline and monthly until 180th day of follow-up. Baseline values of blood pressure (mean ± SD) were 186 ± 19 mmHg/108 ± 13 mmHg in the office, and 151 ± 18 mmHg/92 ± 11 mmHg by 24 h ambulatory blood pressure monitoring (ABPM). Office blood pressure values at 180th day after the procedure were 135 ± 13 mmHg/88 ± 7 mmHg (P < 0.0001, for both comparisons). The mean ABPM decreased to 132 ± 15 mmHg/85 ± 11 mmHg at the 180th day after the procedure (P < 0.0001 for systolic and P = 0.0015 for diastolic). Estimated glomerular filtration (mean ± SD) increased from baseline (64.4 ± 23.9 mL/min/1.73 m(2)) to the 180th day (85.4 ± 34.9 mL/min/1.73 m(2), P < 0.0001) of follow-up. The median urine albumin:creatinine ratio decreased from baseline (48.5, IQR: 35.8-157.2 mg/g) to the 180th day after ablation (ACR = 15.7, IQR: 10.3-34.2 mg/g, P = 0.0017). No major complications were seen. CONCLUSION: The procedure using SICAC seemed to be feasible, effective, and safe resulting in a better control of BP, a short-term increase in estimated glomerular filtration rate, and reduced albuminuria. Although encouraging, our data are preliminary and need to be validated in the long term.