Arteriopathy Program | Research & Innovation

While surgical treatment of pulmonary artery obstructions in elastin arteriopathy was long considered palliative, our cardiac surgeons and cardiologists found an effective way to use surgery as a rehabilitative treatment. Their research in 2000 showed that when surgery is performed in conjunction with balloon dilation of peripheral pulmonary arteries, long-term survival increases.

The underlying cause of congenital SVAS was identified as a loss-of-function mutation of the elastin gene on chromosome 7q11.23, resulting in obstructive arteriopathy. We found that congenital SVAS is not a simple lesion but rather a generalized disease of both pulmonary and systemic arteries, and that the supravalvar stenosis has profound effects on the makeup and function of the aortic valve. These and other key findings in 2000 highlighted the importance of considering all these features when planning treatment.

In 2001, experience with balloon dilation to treat peripheral pulmonary stenosis (PPS) in Williams syndrome (WS) was limited. But a study that year of 16 years of catheterization procedures found that a serial approach of distal dilations, followed by surgical repair of proximal obstruction, led to successful outcomes.

In 1998, research of more than four decades of surgery for supravalvar aortic stenosis confirmed that the results of treatment improved greatly after the introduction of more symmetric reconstruction of the aortic root. Four years later, those Boston Children’s surgeons reaffirmed that repair by direct end-to-end anastomosis is a useful technique in selected cases of discrete supravalvar aortic stenosis.

Patients with congenital supravalvular aortic stenosis (SVAS) and associated pulmonary artery stenosis are inherently at risk for development of myocardial ischemia — which has been connected to cases of sudden death occurring in conjunction with anesthesia or sedation. Research into these cases in 2008 led to the recommendation that all patients with congenital SVAS should be considered at risk for myocardial ischemia on multiple bases and treated accordingly, included meticulous attention during anesthesia to balancing myocardial supply and demand.

Williams syndrome patients who are undergoing coronary artery or combined right-and-left ventricular outflow tract procedures are at high risk of major adverse cardiac events. As a 2018 study detailed, three-patch aortic root reconstruction with extension of the left coronary sinus patch into the left main coronary artery improves quality of life, with no residual aortic or coronary lesions identified on follow-up imaging.

Patients with Williams syndrome are considered at high risk for anesthesia-related adverse events. But a 2018 study of 75 patients who had more than 202 separate anesthetics for cardiac and non-cardiac procedures verified that when patients are appropriately screened and anesthesia providers are well-versed in the hemodynamic goals for Williams syndrome, patients may be anesthetized for non-cardiac procedures safely with minimal morbidity and mortality.

The recoveries of 87 patients — 41 of whom had Williams syndrome — over a 20-year span confirmed that surgical repair of congenital SVAS can lead to excellent long-term survival rates. This was documented in a 2019 study of the patients, who had repairs of concomitant lesions such as right ventricular outflow tract and coronary ostial involvement.