Renal denervation does not involve any pharmacological treatment. It is a multiple application of radiofrequency energy using a thin catheter via the femoral artery and a long-term "denervation" of the sympathetic nerves around the renal arteries. “This is done to prevent an increased excretion of the substances leading to heart failure,” said Dr Táborský.
The aim of this pilot study was to compare the outcomes of patients with advanced heart failure receiving standard pharmacological treatment or renal denervation. Over the period of one year, 26 patients were treated with renal denervation and standard pharmacotherapy and 25 patients received standard drug treatment with beta-blockers, ACE inhibitors or ARBs and diuretics.
After one year contractile function of the left side of the heart improved in patients treated with renal denervation from 25±12% to 31±14% (p<0.01).
There was no change in contractile function of the left side of the heart in patients who received standard drug treatment. "The improvement of the contractile function of the left side of the heart by more than 10% in patients after renal denervation was a surprise,” said Dr Táborský. “This parameter has practically not changed in patients treated by the classic drugs. The difference in response might be explained by a continuous decrease of the renal sympathetic activity in the complex pathophysiology of heart failure."
During the one year follow-up, 8 patients treated with renal denervation were hospitalized due to heart failure compared to 18 patients treated with standard drug therapy. Dr Táborský said: “Twice the number of patients treated by classic pharmacological therapy were taken to hospital due to heart failure.”
The disadvantage of denervation, as with any invasive treatment, is the potential for subsequent complications. "We have registered two complications – the formation of a fistula by the artery and the vein in the place of puncture and the formation of thrombi despite all safety measures being adhered to,” said Dr Táborský. “We have successfully removed both complications by a surgical revision and thromboaspiration.”
The findings indicate that renal denervation may be a non-pharmacological alternative for the treatment of patients with advanced heart failure and may help stabilise the disease. "Renal denervation is particularly suited for patients without an extensive scar after myocardial infarction and whose heart rate increases when they are treated with the maximum tolerated dose of beta-blockers," added Dr Táborský.
He concluded: “The long-term effects of renal denervation should be confirmed in a large international randomised study.”
Miloš Táborský1, Marie Lazárová1, Jan Václavík1
1Department: I. Internal Clinic – Cardiology of Olomouc University Hospital and Olomouc Palacký University, Czech Republic
1 Symplicity HTN-2 Investigators, Esler MD, Krum H, Sobotka PA, Schlaich MP, Schmieder RE, Böhm M. Renal sympathetic denervation in patients with treatment-resistant hypertension (The Symplicity HTN-2 Trial): a randomised controlled trial. Lancet. 2010;376:1903-1909.