Interventional cardiology: Working on a moving heart

CONCORD — Dr. Patrick Magnus of Concord Hospital Cardiology recently discussed interventional cardiology at a panel presentation in Laconia that featured numerous providers from the Concord Hospital Cardiovascular Institute. Dr. Magnus is an interventional cardiologist and the medical director of the Cardiac Catheterization Lab and Structural Heart Program.

What is interventional cardiology?

Interventional Cardiology, a subspecialty of cardiology, uses catheters and intravenous access to treat certain heart conditions including valve disease, heart failure, heart defects, and coronary artery disease. The procedures are minimally invasive and can be performed while the heart is still pumping; instead of stopping it and using a heart-lung machine to bypass its function. Procedures such as TAVR and TMVR for example, are common and can usually be performed in a catheterization lab, instead of an operating room, and involve little recovery time.

What is TAVR?

Transcatheter aortic valve replacement, TAVR, is employed when a major valve that regulates blood flow from the main pumping chamber of the heart becomes narrowed. Symptoms resulting from this can include chest pain, shortness of breath and passing out. TAVR is a minimally invasive procedure, which uses a catheter inserted, most often into an artery at the top of a leg, to place a new valve into the heart. It does not require surgical opening of the chest, so general anesthesia, intubation, and the use of a heart-lung machine are unnecessary. It is accomplished with the heart still moving and is only usually an hour-long procedure. Patients typically go home in the next day or two without the need for rehabilitation. A new valve is placed without opening the chest or stopping the heart.

What is TMVR?

Transcatheter mitral valve replacement, TMVR, though very similar to TAVR, treats severe mitral valve regurgitation, or a leaky valve. With mitral valve regurgitation, blood leaks backward, or regurgitates, as the valve does not close well enough. TMVR is especially useful in treating patients with this condition who are too sick to endure more invasive surgery.

What are some other interventional cardiology procedures?

A few other important procedures to mention are atrial septal defect (ASD) and patent foramen ovale (PFO) closures, Impella implantation, atherectomy, and intravascular lithotripsy. Sometimes people have holes between certain chambers of the heart that we can close, as with ASD and PFO closures, where a permanent closure device is inserted via a catheter-based, minimally invasive procedure. An Impella device is a tiny pump that can be inserted in either the left side of the heart, the right side, or both to aid the heart in pumping. This temporary support may be required in a patient with heart failure or when one must undergo complex coronary stent procedures. Atherectomy is the removal of plaque or buildup in the arteries. Different devices, somewhat like a Roto-Rooter, may be used to accomplish this: namely rotational, orbital, or laser atherectomy devices. Intravascular lithotripsy is also used in an effort to clear blockages, but with sound waves.

How is a particular procedure chosen for a particular patient?

Sometimes, it is automatically evident what type of procedure or device is needed, such as with ASD and PFO diagnoses. Other times, more information is required to determine the best course of action. The field of cardiology eventually discovered that not all blockages are the same, for instance. Fortunately, we now have various imaging studies that we can perform to give us more information. Advanced intracoronary imaging, like intravascular ultrasound (IVUS) and optical coherence tomography (OCT), are used to better understand the nature and composition of coronary blockages. The results of these imaging studies help map out and assess blockages, informing us where the problem is exactly and if the blockage is cholesterol, calcium, or the result of a tear in the vessel. We can then determine what size stents to use, as well as whether atherectomy, lithotripsy, or another procedure would yield an optimal outcome for the patient.