Treating an overlooked heart condition

Marissa Eustaquio’s case was a mystery. After a strong recovery from heart surgery as a child, she’d been active for years, enjoying dancing, hula, gymnastics, running, and bike-riding. But as a young teenager it became increasingly hard for her to do not only athletic activities, but any activities at all. Sidelined by chest pain and difficulty breathing, Marissa was soon unable to climb stairs or walk around the mall without sitting down to rest.

“We lived in a two-story house,” said her mother, Patria Eustaquio. “I had to move her bedroom to the first floor so she wouldn’t have to climb stairs.” In 8^th grade Marissa had to drop out of PE class, and then stopped going to school entirely. “She was homeschooled for 9^th, 10^th and part of 11^th grade,” said Patria.

Marissa’s health history was complex. She was born in 1998 with coarctation of the aorta, a narrowing in the main artery that delivers blood to the body, which prevented her blood from circulating properly. She was also found to have a patent ductus arteriosus – a connection between the aorta and the pulmonary artery, the main artery that delivers blood to the lungs. Marisa had surgery when she was 7 months old to correct these conditions, and had additional surgery when she was 7 years old to address a subaortic membrane – an obstruction that restricted blood flow between her left ventricle and her aorta.

Marissa enjoyed an active, healthy childhood following this surgery. However, at age 13, she began to experience chest pain. Comprehensive evaluation for a cause of this pain found blood test results consistent with lupus, an autoimmune condition. Yet, despite treatment for lupus, her chest pain persisted. With no clear explanation for her chest pain, she had surgery at age 14 to remove temporary pacing wires remaining from her most recent heart surgery, in the event that they might be the cause. Still, her chest pain persisted, and was soon accompanied by difficulty breathing whenever she increased activity.

Terry Robinson, MD, associate professor of pediatric pulmonology at Lucile Packard Children’s Hospital Stanford, wasn’t able to link Marissa’s symptoms to her mild asthma, which was well controlled with medication. He obtained a CT scan of her chest, which suggested that one of the airways in Marissa’s lungs might be mildly narrowed. So, he brought the images from the CT scan and a bronchoscopy – an internal scan of her airways – to the weekly multidisciplinary meeting of cardiologists and cardiothoracic surgeons that takes place every Wednesday morning in the Heart Center at Lucile Packard Children’s Hospital.

Ian Rogers, MD, MPH, clinical assistant professor of cardiovascular medicine and pediatric cardiology, happened to be at that meeting. Because the Stanford Adult Congenital Heart Program spans both the pediatric and adult hospitals, the attendees include cardiac specialists and surgeons who treat all ages. When Dr. Robinson showed the images from Marissa’s CT scan, Dr. Rogers noticed that Marissa appeared to have a common heart condition – so common that it is estimated that about one quarter of the population lives with it, usually symptom-free. The condition, a myocardial bridge, is considered so benign that most medicals schools don’t even teach it. Most doctors dismiss it, and when patients do have symptoms, they often misattribute its symptoms to stress or anxiety.

However, in recent years, Dr. Rogers and his colleagues, including Ingela Schnittger, MD, professor of cardiovascular medicine, have been looking more closely at myocardial bridges, a condition in which the left anterior descending coronary artery, or LAD, tunnels through the heart’s muscle layer rather than resting on the outside of it, as it should. The location and extent of myocardial bridge varies in each patient, with symptoms of chest pain, shortness of breath, and sometimes arrhythmia more or less severe – or completely absent. In the rarest, most extreme cases, sudden cardiac arrest has been attributed to a previously undiagnosed myocardial bridge. Schnittger, Rogers, and their colleagues have shown that surgical treatment dramatically improves quality of life for patients who, like Marissa, are unable to perform even basic activities due to their symptoms.

Dr. Rogers referred Marissa for diagnostic tests, including a second CT scan focused on her heart, which confirmed that she had a myocardial bridge. He then followed with other diagnostic exams that would give her care team a comprehensive picture of her condition.

“We perform a very specialized cardiac catheterization that is only offered by a few hospitals in the U.S.,” says Rogers. The procedure, including intravascular ultrasound and intracoronary hemodynamic assessment, would show how long and deep Marissa’s myocardial bridge was and whether and to what degree it was disturbing her blood flow. “Sure enough,” said Rogers, “her test was indeed abnormal.” Marissa had a myocardial bridge that was compromising her blood flow and causing her debilitating symptoms.

In September 2013, Marissa was the first pediatric patient at Lucile Packard Children’s Hospital to undergo the “unroofing” surgery to correct her myocardial bridge, performed by Katsuhide Maeda, MD, clinical associate professor of cardiothoracic surgery, and R. Scott Mitchell, MD, emeritus professor of cardiothoracic surgery.

Cleared for all the activities she once enjoyed, Marissa returned to high school full-time for her senior year and is now in her first year of college, studying pre-nursing. Her career choice is a hat tip not only to her care team at Packard Children’s, but to her mother, Patria Eustaquio, RN, a senior nurse in Packard Children’s cardiac step down unit, where her own experience as a parent serves as a support to families and nurses alike.

“Seeing anyone’s life altered for the better is very rewarding,” says Dr. Rogers. “But to see a young person’s life altered in such a positive way is particularly satisfying for me as a physician and for my colleagues.”