Surgical Repair of Congenital Heart Defects Improves Survival in PAH Patients, Study Shows

Surgery to repair congenital heart defects leads to longer survival in patients with pulmonary arterial hypertension (PAH) caused by heart disease, according to researchers.

This finding was reported in the study, “Contemporary survival of patients with pulmonary arterial hypertension and congenital systemic to pulmonary shunts,” published in the journal Plos One.

Congenital heart defects, such as systemic-to-pulmonary shunts, are caused by blood volume overload of pulmonary circulation during the early stages of a patient’s life. If left untreated, heart defects can cause irreversible changes to the lung vessels, leading to progression of pulmonary hypertension and pulmonary disease. A cardiac shunt

The prevalence of PAH caused by congenital heart disease (CHD) has increased by 5 percent in the past few decades. This reflects improvements in PAH-CHD patient care, but it also raises long-term monitoring concerns.

For better insights on PAH-CHD patient outcomes, a team at the Faculty of Medicine from Siriraj Hospital in Bangkok — one of the main referral hospitals in Thailand for congenital heart surgery and intervention — retrospectively reviewed the clinical outcomes of newly diagnosed PAH-CHD patients.

They analyzed the records of 366 patients with PAH-CHD who met the study’s criteria and were diagnosed in Siriraj Hospital from 1995 to 2015. The mean age at diagnosis was 24.5, and 40% of the patients were males. The majority of the patients had a simple congenital alteration that led to pulmonary shunts, and 20% had complex CHD.

Based on the clinical characteristics of the patients, 26.8% of them were described as having Eisenmenger syndrome (severe blood oxygenation impairment), 66.7% had prevalent left-to-right shunts, 3% had PAH with a small defect, and 3.5% had PAH after corrective heart surgery.

During a mean follow-up period of 5.9 years, several treatment approaches were used to treat the different types of congenital heart disease, including surgery and pulmonary vasodilator drugs.

Despite the treatments, all reported deaths were primarily related to cardiac complications.

Overall, the survival rate for these PAH-CHD patients at five years was 95.3%; at 10 years, 88.6%; and at 15 years, 84.6%.

Comparing the survival rates of the patients based on the type of clinical characteristics, the researchers found that those with PAH and small heart defects had lower survival rates than those with any other type of PAH-CHD condition.

Patients who had PAH with prevalent systemic-to-pulmonary shunts had better survival rates, with 95.8% surviving at five years, and 92.6% at 10 and 15 years of follow-up.

Patients who were surgically treated showed better survival rates than those who weren’t eligible for surgery, with a 91.5% survival rate compared with 68.4% at 15 years.

“The superior survival rate for the group undergoing operations suggests that the deliberate selection of patients for an intervention closure is crucial and may improve their survival outcomes,” the researchers wrote.

The team identified several risk factors that contribute to poorer outcomes in PAH-CHD patients, including elevated right atrial pressure, age at diagnosis, WHO functional classification at diagnosis, and high pulmonary vascular resistance at diagnosis.

These results show that PAH-CHD patients have a “modest long-term survival” that is, in part, dependent on treatment decisions. This highlights the importance of attentive monitoring and follow-up of these patients to achieve the best long-term outcomes, the researchers said.