By Kyle LoJacono
Pasco Regional Medical Center in Dade City has introduced a new diagnostic technique to test for heart problems.
Tharen Leesch, cardiac catheterization lab director, said the procedure uses inhaled nitric oxide to help identify proper medications for various degrees of pulmonary hypertension, a form of high blood pressure.
“The nitric oxide study is to determine if a certain type of drug will help bring the pressure down,” Leesch said. “If it doesn’t reduce the pressure, then these certain drugs won’t either. So it’s a good way to test the effectiveness of a type of treatment.”
Leesch said nitric oxide is nothing like nitrous oxide, or laughing gas.
“They act very differently in the body,” Leesch said.
The first such procedure done at Pasco Regional was on July 27 by Dr. Chirag Shah.
“We put a mask on that delivers the amount of gas that is prescribed by the physician,” said Becky Young, Pasco Regional director of respiratory therapy. “It’s on for about five minutes.”
It is done during a right heart catheterization.
“Right heart caths aren’t done as much as they used to be 10-15 years ago,” Leesch said. “That’s because we can do a lot of measurements with ultrasounds now, but this is the gold standard. We can go in with a cath into the right side of the heart into the pulmonary vein and it checks the total pressure on the lung side of circulation. Then the nitric oxide is introduced and we see if the pressure comes down.
“The way it works is arteries and veins have smooth muscle along them,” Leesch continued. “The nitric oxide will let those muscles relax.”
Leesch said the right side caths are not what most people think of when they talk of cardiac catheterization.
“Standard cardiac catheterizations people hear about are on the left side,” Leesch said. “That is more coronary issues and heart attacks. With right side it’s more about the pressure with the lungs and pulmonary vein.”
The pulmonary vein and artery are what bring blood to the lung and then back into the heart to be pumped throughout the rest of the body. The nitric oxide treatment does not directly relate to lung function, but many people with pulmonary hypertension have shortness of breath. That is what makes identifying the problem somewhat of a challenge, according to Young.
“They haven’t been able to pin it down as a lung issue or a pulmonary issue,” Young said. “These people have gone through and tested their lungs and they seem to be fine, but they’re still very short of breath especially with exercise. This helps us also determine if it is lung function, heart function or a structural issue.”
If it is a structural issue causing the high blood pressure, such as an overly tight valve, the nitric oxide will not help. Leesch said that helps doctors and patients find the best treatment options without wasting time.
If untreated, pulmonary hypertension can lead to heart failure. Leesch said the condition can be genetic.
“It also depends on the kind of exposures they have that can cause reaction,” Leesch said. “It’s kind of like asthma where it can be genetic, but there are things in the environment that can lead to people developing it. They may have worked in some construction zone or been exposed to some toxic chemical. We’re still trying to identify exactly what causes it, but there doesn’t seem to be a group that suffers from it more.”
Young said nitric oxide has been used for years in pediatrics and with other diagnostic tests.
“It’s extremely safe,” Young said. “I searched a great deal of the literature to see if there were any safety issues that we might need to address and be prepared for, and I couldn’t find anything that said it could be dangerous in any way. As with any therapy and medication there can be rare side effects, and that is why we have a respiratory therapist in the room during the study just to be sure.”
Leesch said the nitric oxide study is not currently being done at many other area hospitals.
“I believe the only other two hospitals in the Tampa Bay area are Tampa General and the VA in Tampa,” Leesch said.
Leesch added, “I think it’s a bit unusual for a community of this size to have this kind of tool. It’s not available in all cath labs, so we’re delighted to be able to offer this option to the community.”
For more information on Pasco Regional, visit www.pascoregionalmc.com or call (352) 521-1100.