The doctor, who was part of a team that brought path-breaking surgery to Canada, in conversation with Ajit Jain
Three specialists performed ground-breaking surgery at the Peter Munk Cardiac Center, oToronto General Hospital, January 18, to reduce a 57-year-old patient's blood pressure.
Reports say some 2,50,000 Canadians suffer from high blood pressure that can't be controlled with medicines. Luis Martins was taking six different medicines before the surgery.
After the renal denervation surgery, his BP declined from a life threatening 225/125 to 130/75 and he is down to one medication, says Dr Dheeraj Rajan, an interventionist radiologist who performed the surgery along with cardiologist Dr Douglas Ing and vascular surgeon Dr George Oreopoulos.
Though this kind of surgery has happened in Europe, it was a first for Canada. The Munk Center had to seek approval of the Ministry of Health and College of Physicians and Surgeons before performing the surgery.
Please explain this new procedure.
There are two kinds of high blood pressure. Some people have high BP because of a problem with the arteries going to the kidneys, often causes by atherosclerosis. We can treat that by putting a balloon and/or stent, but that represents only 5 percent or less of patients with high BP.
Majority of high BP patients don't have any narrowing of the nerves going to the kidneys. The kidneys are part of the mechanism that control BP, so there's normal blood flow to the kidneys yet for some reasons they develop high BP.
Two randomised studies have been done in regard to this procedure in Australia and Europe on patients who take proper medication, but are not responding well to it or have complications from the medications.
In the 1950s, before these medications existed, surgeons would make an incision in the belly, cut the nerves around the abdominal aorta and by cutting these nerves they would correct the blood pressure. But there was a major complication when those nerves were cut. The blood vessels wouldn't react normally below the cuts causing other problems for the rest of the body.
So, when people would sit up or move quickly, or have to do something quickly, their blood vessels wouldn't tighten up properly, and they would pass out, they would fall down and they wouldn't be able to raise the blood pressure when they needed to. It was very effective in one way, but it created a bigger problem.
During the last 40-50 years, the procedure wasn't done and during this time medications improved a great deal. But there are still patients who don't do well with these medications.
The incidence of high BP is only going up despite improvements in medications We are seeing people with more strokes and more heart and kidney failures. Renal failure is a big problem in India, which is very poorly managed there right now. It is better managed in North America, but the number of people who are on dialysis is going up significantly here as well.
Now, with advances in technology, what we did as a team was we went up the arteries, to the kidneys and delivered, through a catheter, a very specific type of energy that burns the nerves outside the kidney arteries, which act as a circuit to send feedback readings to the brain. By disrupting those circuits, we break the feedback to raise the blood pressure.
This is very specific to areas around the kidneys and not to anywhere else in the body.
Three of us were operating. I was doing the procedure; Douglas and I had trained together in Germany. George was assisting, and he was there in case of any problems, though complications are rare.
Is this the first time this surgery has been done here?
Yes. In the 1950s, we had to open up the belly; it used to be a prolonged surgery and the patient had to be in the hospital for some time. This (the new surgery) is done with a 2 mm hole. We are targeting the nerves much more specifically than the old way. This procedure takes about one hour; no staples, no stitches, no cutting.
The patient comes in the morning for the procedure and can go home in the evening or next morning.
How has the patient been doing?
This procedure is done for those patients who are on multiple medications and are not responding to them. This patient was on six medications. His blood pressure since he was discharged (three days at interview time) is normal -- 130 over 70-80 -- and he's taking only one medication now.
Actually it is a bit of a surprise that he has responded so very well. We don't expect all patients to respond well so soon.
In both studies (in Australia and Europe), they have stated that some patients responded immediately, but most responded a few weeks after the procedure.
Is there a high mortality rate associated with elevated BP?
Yes. And it is very prevalent in the South Asian population. Our people have all kinds of cardiac complications as a result. It is a risk factor that's controllable with proper medications. Hypertension, as we know, results in heart diseases, strokes, kidney failure and various vascular diseases.
How soon do you see this procedure becoming common?
It could become common between one to two years. We are now looking at clinical trials at the Peter Munk Cardiac Center We are handling this as a team. We have found that if you involve the right specialists, the patient gets the right treatment.