Abstract-Percutaneous renal sympathetic denervation by radiofrequency energy has been reported to reduce blood pressure (BP) by the reduction of renal sympathetic efferent and afferent signaling. We evaluated the effects of this procedure on BP and sleep apnea severity in patients with resistant hypertension and sleep apnea. We studied 10 patients with refractory hypertension and sleep apnea (7 men and 3 women; median age: 49.5 years) who underwent renal denervation and completed 3-month and 6-month follow-up evaluations, including polysomnography and selected blood chemistries, and BP measurements. Antihypertensive regimens were not changed during the 6 months of follow-up. Three and 6 months after the denervation, decreases in office systolic and diastolic BPs were observed (median: Ϫ34/Ϫ13 mm Hg for systolic and diastolic BPs at 6 months; both PϽ0.01). Significant decreases were also observed in plasma glucose concentration 2 hours after glucose administration (median: 7.0 versus 6.4 mmol/L; Pϭ0.05) and in hemoglobin A1C level (median: 6.1% versus 5.6%; PϽ0.05) at 6 months, as well as a decrease in apnea-hypopnea index at 6 months after renal denervation (median: 16.3 versus 4.5 events per hour; Pϭ0.059). In conclusion, catheter-based renal sympathetic denervation lowered BP in patients with refractory hypertension and obstructive sleep apnea, which was accompanied by improvement of sleep apnea severity. Interestingly, there are also accompanying improvements in glucose tolerance. Renal sympathetic denervation may conceivably be a potentially useful option for patients with comorbid refractory hypertension, glucose intolerance, and obstructive sleep apnea, although further studies are needed to confirm these proof-of-concept data. (Hypertension. 2011;58:559-565.)

Recent studies indicate that resistant hypertension (RHTN) is present in about 12% of the treated hypertensive population. However, patients with true RHTN (confirmed out of the office) have not been widely studied. We prospectively studied 204 patients (123 male, 81 female, mean age 48.4 years, range 19-65 years) with truly RHTN (ambulatory daytime mean blood pressure >135/85 mm  Hg). We evaluated the frequency of obstructive sleep apnea (OSA), renal artery stenosis (RAS), primary aldosteronism (PA) and other secondary forms of hypertension (HTN) and conditions. Mild, moderate and severe OSA were present in 55 (27.0%), 38 (18.6%) and 54 (26.5%) patients, respectively. Secondary forms of HTN were diagnosed in 49 patients (24.0%), the most frequent being PA (15.7%) and RAS (5.4%). Metabolic syndrome (MS) was present in 65.7% of patients. Excessive sodium excretion was evident in 33.3% of patients and depression in 36.8% patients. In patients with RHTN, OSA and MS were the most frequent conditions, frequently overlapping with each other and also with PA. Our data indicate that in the vast majority of patients with truly RHTN, at least one of three co-morbidities-OSA, MS and PA-is present. Other conditions, even though less frequent, should also be taken into the consideration.

In conclusion, renal artery stenosis is prevalent in a significant proportion of patients undergoing cardiac catheterization. Renal angiography should be considered particularly in hypertensive patients with multivessel coronary disease coexisting with cardiovascular risk factors, even moderately impaired renal function and increased carotid IMT or vascular disease elsewhere.

Abstract-It has been postulated that catheter-based renal denervation (RDN) may lower blood pressure (BP) and improve severity of obstructive sleep apnea (OSA) in resistant hypertensive patients. The aim of our study (NCT01366625) was to investigate in a prospective randomized trial the effect of RDN on BP and clinical course of OSA. Sixty patients with true resistant hypertension coexisting with moderate-to-severe OSA (apnea/hypopnea index, ≥15) were randomly allocated to RDN group (30 patients) and to control group (30 patients). The primary end point was reduction in office systolic BP at 3 months. Secondary end points included reduction in diastolic office and ambulatory BP, change in apnea/hypopnea index and biochemical measurements at 3 months, and change in echocardiographic measurements at 6 months. There were no differences in clinical characteristics between the groups. At 3 months in the RDN group, both office and ambulatory BP were significantly reduced, and a significant decrease in OSA severity (apnea/hypopnea index, 39.4 versus 31.2 events per hour; P=0.015) was observed. Between-group difference in apnea/hypopnea index change was significant at 0.05. At 6 months in the RDN group, reductions in office and ambulatory BP were sustained and were accompanied by significant improvement in echocardiographic measures of global longitudinal strain. There were no differences in metabolic variables in follow-up in both groups. In a randomized controlled trial, RDN lowered both office and ambulatory BP in patients with resistant hypertension and OSA. This was accompanied by improvement of the clinical severity of OSA. Clinical Trial Registration-URL: http://www.clinicaltrials.gov. Unique identifier: NCT01366625.