Renal Denervation Screening Clinic
Institut Jantung Negara Kuala Lumpur offers a catheter based renal sympathetic denervation solution for suitable patients with resistant hypertension. On 14th September 2011, Institut Jantung Negara became the first centre in Asia to perform a new technique of treating patients with Resistant Hypertension. The procedure is bilateral renal artery denervation using the Symplicity® Catheter system (Ardian).
Resistant hypertension
High blood pressure or Hypertension is a common disorder and affect at least 30 to 40% of the adult population in the developed world. Most patients who suffer from hypertension do not have any symptoms. However many studies have shown higher blood pressure is associated with increased risk of ischaemic heart disease and stroke. A study by MOH, J.p et al showed that lowering blood pressure by as little as 5mmHg can reduce the risk of stroke by almost 30%. However in some instances, Blood Pressure remains above target goals despite intensive therapy. While these patients are considered as uncontrolled hypertension due to various reasons like non-compliance to medications, White-coat hypertension or pseudohypertension, there are those that are truly resistant to treatment.
The science behind renal denervation
Resistant hypertension is defined as systolic blood pressure of more than 160 mmHg (more than 150mmHg for the diabetic patient) despite being on 3 or more antihypertensive medications. The pathophysiology of hypertension is complex and not fully understood. But what we do know is that the renal sympathetic nerve that innervates the wall of the renal artery is important in the pathology of hypertension. It regulates the sodium retention, stimulation of the renin release and reduction of the renal blood flow. The hyperactivation of these factors lead to hypertension. Studies have shown that inhibiting the sympathetic nerve via surgical means will lower the blood pressure. The SYMPLICITY HYPERTENSION TRIAL has shown that renal denervation is a safe procedure that causes blood pressure reduction in patients with resistant hypertension. A device-based, percutaneous approach of selectively denervating the renal sympathetic nerves using Radiofrequency Ablation, the Symplicity® Catheter system was developed by Ardian for this very reason (Picture 1, courtesy of Ardian Medtronic).
The Simplicity Catheter
Radiofrequency generator
Source: Ardian Medtronic
Resistant Hypertension clinic
In IJN, we started a Resistant Hypertension clinic together with Professor Abdul Rashid from Cyberjaya University of Medical Sciences (CUCMS), to screen and review all patients with uncontrolled hypertension. Those with true Resistant Hypertension, meeting a set of criteria will be offered RDN. The IJN foundation has graciously donated 30 sets of Symplicity catheters for us to start off the procedure and we are offering these free of charge for Malaysian patients meeting the criteria.
Currently, RDN is offered only to patients with Resistant Hypertension. The data so far have been very promising, with good safety and efficacy. With larger trials, we will be able to assess if this procedure is also suitable for a larger population of Hypertensive patients.