Modern medicine continues to make great strides in the treatment of illness and disease of all kinds, and heart and vascular care are no exception. Recently, some of the most exciting advances in cardiovascular medicine have been in the treatment of structural heart disease, which involves any defect or abnormality of the heart that is noncoronary—meaning that the blood vessels in the heart are not affected.
Structural heart disease encompasses a multitude of cardiac conditions that compromise the integrity of the heart’s valves or chambers, including defects between the top two chambers (such as occurs with conditions like atrial septal defect and patent foramen ovale), defects between the lower chambers of the heart (ventricular septal defect), and valvular heart disease like stenosis (tightening of heart valves) and regurgitation (leaking of heart valves).
Many structural heart conditions are congenital (present at birth), but these abnormalities also can form later in life due to wear and tear from aging, infection or other underlying conditions.
Innovative Interventional Structural Heart Procedures
The field of interventional cardiology was born in 1977, when Dr. Andres Gruentzig, a German radiologist, performed the first human balloon angioplasty to relieve obstruction in the coronary arteries that supply the heart. Prior to the development of this procedure, the only way to treat significant coronary artery blockages was with coronary artery bypass graft surgery.
The following four decades have seen extensive advancements in the field, many of which involve catheter-based, nonsurgical treatment of coronary artery disease, while other procedures take place outside the confines of the coronary arteries. The beauty of catheter-based cardiac procedures is that they can be performed with the smallest of incisions, without the need for open-heart surgery. Catheter-based procedures used to treat cardiac structures and valve abnormalities are now referred to as structural heart disease interventions. Given the tremendous advances in structural heart interventions in the past 10 years, structural heart disease has emerged as its own subspecialty within interventional cardiology.
Reducing the Need for Invasive Open-Heart Procedures
The accompanying diagram summarizes the scope of structural heart disease. Atrial septal defects, patent foramen ovale, ventricular septal defects and patent ductus arteriosus are defects or abnormal connections that cause abnormal blood flow among the different chambers of the heart. Most of these abnormalities can now be closed with structural heart disease interventions, and without the need for open-heart surgery.
“Left atrial appendage” in the diagram refers to a pocket in the upper chamber of the heart where clots can form in patients with atrial fibrillation, a common irregular heart rhythm. Without the use of blood-thinning anticoagulant medications, these types of clots can lead to stroke. However, many patients cannot take blood thinners due to prior episodes of significant bleeding. Now, however, with catheter-based intervention, many of these patients can have the appendage occluded (closed) surgically, reducing their risk of stroke while also keeping them off blood thinners.
Multiple other structural cardiac conditions now also can be managed with similar, minimally invasive techniques.
Repairing Faulty Heart Valves
The most significant advancement in the field of structural heart disease has been in the management of valvular heart disease. Heart valves are structures that separate the upper and lower cardiac chambers and also allow blood to flow from the lower chambers of the heart to the aorta, the largest artery in the body that supplies blood to all organs, and the pulmonary arteries, which supply blood to the lungs. These valves are prone to developing stenosis (narrowing) or regurgitation (leaking) due to different disease processes.
About a decade ago, the only option for managing these conditions was open-heart surgery, but catheter-based interventions have become an increasingly common alternative.
One such therapy that has proved to be a significant medical breakthrough is transcatheter aortic valve replacement (TAVR). The aortic valve, located in the lower left chamber of the heart, controls blood flow into the aorta. Over time, the aortic valve can become calcified, causing a narrowing in the valve opening—a condition known as aortic stenosis. This type of narrowing may also result from a birth defect, rheumatic fever or radiation therapy.
Previously, open-heart surgery was considered the gold standard for replacing a diseased aortic valve. Unlike open-heart procedures, TAVR requires only a small incision in the groin or through the chest directly into the aorta. Then, using a thin catheter, the interventional cardiologist implants a new valve over the diseased valve to restore full blood flow.
In addition to being less invasive, TAVR offers multiple benefits, including the lack of need for patients to be placed on a heart-lung machine, quicker recovery times, shorter hospital stays and significantly less pain than with open-heart surgery.
TAVR is also a great option for patients who cannot have traditional aortic valve surgery due to patient risk factors such as age, frailty or other health issues. For many such high-risk patients, TAVR can extend life span and significantly improve quality of life.
A New Era in Cardiovascular Medicine
The exciting field of structural heart disease has expanded significantly over the past decade. Increased recognition and understanding of the disease processes involved in structural heart conditions, as well as the development of catheter-based approaches to treat these processes, indeed have heralded a new era in cardiovascular medicine. The results of ongoing clinical trials, as well as the inevitable evolution of new technology, promise to continue shaping the field for decades to come.
The heart team at Sentara RMH joined this new wave of innovative cardiac care with the introduction of TAVR at the hospital earlier this year (see the feature article beginning on page 32 about the experience of two Sentara RMH Medical Center patients who recently underwent the TAVR procedure). In addition to TAVR, we also offer numerous other structural heart disease interventions with the aim of providing—locally, in our own community—excellent patient care, the highest quality of life and improved longevity for our cardiac patients.
Meet Dr. Salman Allana
Sentara RMH Medical Center welcomes Salman S. Allana, MD, an interventional cardiologist who has joined the Harrisonburg Medical Associates team at Sentara Evelyn Byrd Health Center.
Dr. Allana graduated from Aga Kahn University Medical College in Karachi, Pakistan. He completed his internship and internal medicine residency at the University of Wisconsin–Madison, where he also completed a fellowship in cardiovascular disease and a fellowship in interventional cardiology.
Board-certified in internal medicine, cardiovascular medicine, nuclear cardiology and interventional cardiology, he is an integral part of the new Sentara Heart Valve & Structural Disease Center at Sentara RMH.