I'm Aware That I'm Rare: Raymond Benza, MD
Dr. Raymond Benza is a cardiologist in Pittsburgh, Pennsylvania and is affiliated with multiple hospitals in the area, including Alle-Kiski Medical Center and Allegheny General Hospital. He has been in practice for more than 20 years. Dr. Benza discusses the benefits of inhaled iNO (nitric oxide) in patients with pulmonary hypertension.
My name is Dr. Raymond Benza and I’m a PH clinician and researcher.
We’re going to talk a little bit about nitric oxide. It’s importance in pulmonary hypertension and in some of the interesting clinical work that we’re doing with this particular molecule.
Nitric oxide is a molecule that the body utilizes to keep the blood vessels in the lungs wide open and rushing with blood. In patients with pulmonary hypertension, the blood vessels in the lungs no longer make this molecule. We don’t know why. We think it may be related to some genetic predisposition, but when the absence of this molecule, the blood vessels constrict and result in pulmonary hypertension. This is probably the most potent blood vessel dilator known to mankind. That’s why it’s so essential to have this in the body of people who have pulmonary hypertension because it really in essence, can bring the blood vessels back to a normal tone, and ease the stress off their heart.
This molecule we know can be delivered therapeutically and actually we’ve had chemical forms of this compound that’s been available for use for many years. The problem with it is that it’s delivered as a gas, and people have to inhale it. The tanks that are required to deliver this are huge. There’s no way people can walk around with these things. We’ve only been able to use this life saving medication in the hospital when someone is very, very sick with pulmonary hypertension and in many instances, it’s been life saving. It’s gotten people out of the crutch and allowed them to get put on regular medications and have an improved outcome.
Some pretty smart engineers figured out a way to miniaturize the cylinders so they can be carried in a hip like structure and people can walk around with it and they can be delivered just like they wear oxygen. That’s essentially the essence of the study that we completed. We looked at the first ambulatory form of nitric oxide for treatment of pulmonary hypertension.
The study was conducted over several years and patients who were already on therapy for pulmonary hypertension but who had not yet met their clinical goals, meaning they were still breathless when they were trying to do the things they like to do every day, were randomized to get this medication or not. Then we saw how they did. At the end of the day, the patients who received the gas, if they used it correctly, meaning they used it all day and didn’t take frequent breaks from it, seemed to walk longer and have improvements in the way their heart circulates blood.
Obviously it was very dependent upon patient compliance. How often they used it, how long they used it, and if they used it throughout the day as opposed to in very short cycles. I think we’ve shown at least a signal that this form of walking around medicine might be useful in patients with pulmonary hypertension to help them live longer and breathe better.
The six minute walk test is really one of the most simple tools that we have to measure someone’s functional capacity who is stricken with diseases like heart failure. It’s simple having someone walk up and down a hallway for six minutes and to see what kind of distance they can attain in that six minutes.
Obviously, someone who can walk a longer distance in six minutes, has a better functional capacity that someone who can’t walk very far in six minutes. It’s really been used as the gold standard for measuring outcome and pulmonary hypertension for many, many, many years. The smaller study that we did and that’s being presented at the International Society of Heart and Lung Transplant meeting is we used this ambulatory form of nitric oxide during patient’s six minute walk tests. We found that those patients who utilized it during a walk, had much improved functional capacity than those who didn’t.
Interestingly, in the patients that we looked at, they had another novel in dwelling hemodynamic monitor called a CardioMEMs monitor that monitors their pulmonary pressures 24 hours a day. We were able to see what their pulmonary pressures did with exercise and those who did or did not wear their nitric oxide. Those who did seemed to have a much better hemodynamic response to walk than those who didn’t.
Presently, patients who are using the inhaled nitric oxide still have to take their PH medications. We have yet to determine whether people can be weaned off these medications and just use the nitric oxide. Luckily, and the medication has very, very few side effects, which is similar to what we’ve seen when we utilize the gas in the hospital. It doesn’t cause your blood pressure to be low. It doesn’t cause any strange neurological effects and it’s usually very well tolerated.
My name is Dr. Raymond Benza and I’m aware that I’m rare.