Amresh Raina, MD, is director of the Advanced Heart Failure and Pulmonary Hypertension Program at Allegheny General Hospital and the Allegheny Health Network in Pittsburgh, Pennsylvania.
Amresh Raina, MD, is director of the advanced heart failure and pulmonary hypertension program at Allegheny General Hospital and the Allegheny Health Network in Pittsburgh, Pennsylvania. He is board-certified in advanced heart failure, echocardiography (imaging of the right ventricle), and general cardiology.
How do the pathophysiologies of heart failure and chronically elevated pulmonary pressure intersect?
That’s a very interesting question. Pulmonary hypertension, first of all, is a broad term, saying that the pulmonary artery pressures—the pressures in the blood vessels of the lungs—are elevated, but doesn’t really say why they’re elevated. And so the first thing to note is that there are multiple different reasons and pathophysiologies at work in the development of pulmonary hypertension.
There are specific forms of pulmonary hypertension that are related to elevated resistance in the blood vessels of the lungs, and those are pulmonary arterial hypertension—we call that WHO [World Health Organization] Group 1, as well as chronic thromboembolic pulmonary hypertension, [and] that’s WHO Group 4. Those are diseases that lead to elevation and resistance in the blood vessels of the lungs, narrowing and constriction of the blood vessels. That elevates the pulmonary artery pressures, but also causes the right side of the heart to have to work harder to overcome that resistance and those pressures. And that can lead to right-sided congestive heart failure, symptoms of shortness of breath, swelling in the lower extremities, etc.
However, there are other forms of congestive heart failure that can cause pulmonary hypertension. Patients who have left-sided congestive heart failure, whether that’s due to lower left ventricular ejection fraction—what we call heart failure with reduced ejection fraction—or in patients who have heart failure symptoms but preserved left ventricular ejection fraction, both of those entities can cause elevation in pressures on the left side of the heart and that pressure can back up into the lungs and cause secondary pulmonary hypertension. That’s a different group of pulmonary hypertension, which we call related to left heart disease or WHO Group 2.
So, pulmonary hypertension can be the disease in and of itself, impacting the right side of the heart, or it can be a manifestation of a left-sided heart problem.
Dr. Raina is a nationally renowned physician with expertise in the diagnostic evaluation and management of pulmonary hypertension. His particular interest is in advanced imaging of the right ventricle in pulmonary arterial hypertension. He has published extensively in this field, with numerous peer-reviewed manuscripts, abstracts, and book chapters. Dr. Raina was named one of Pittsburgh Magazine's "Best Doctors" in 2019.