Striking as this effect was, perhaps even more notable was a report last year from a separate pilot study that randomized 50 patients who met the same definition of refractory hypertension. In addition to showing similar blood pressure results in the denervated patients, the researchers on this study also looked at several measures of glucose metabolism. At 3 months after intervention, the 37 denervated patients had an average 9% cut in their fasting blood glucose level and an average 12% drop in their average fasting blood insulin levels, both statistically significant changes from baseline, compared with no significant change in the 13 control patients. The percent of patients with normal glucose tolerance rose by 11% in the denervated group, and dropped by 7% in the control group. The authors of the report concluded that renal sympathetic activity plays a role in insulin resistance (Circulation 2011;123:1940-6).
Future studies will likely examine the possible impact of renal denervation on heart failure and on obstructive sleep apnea, noted Dr. Jaff.
Dr. Jaff said that he has financial relationships with several cardiovascular device companies including Medtronic Hansen Medical and Medtronic Vascular. Dr. Sievert said that he has financial relationships with several cardiovascular device and pharmaceutical companies including Ardian and Medtronic.