A heart chamber malfunction leads to worse survival in pulmonary arterial hypertension (PAH) patients who have had a double lung transplant, a study reports.
The malfunction, known as diastolic dysfunction, occurs when the heart’s left ventricle is unable to fill up with blood before pumping it out to the body.
Researchers published the study in the American Journal of Transplantation. The title is “Impact of Left Ventricular Diastolic Dysfunction on Lung Transplantation Outcome in Patients With Pulmonary Arterial Hypertension.”
The study compared survival a year after a double lung transplant in PAH patients with diastolic dysfunction and patients without it. People with congenital heart disease-PAH, or CHD-PAH, were excluded from the research.
Fourteen of the 44 PAH patients in the study who had a double lung transplant between January 1995 and December 2013 — or 32 percent overall — experienced diastolic dysfunction before their transplant. Patients with the dysfunction had a more severe disease than the 30 patients without it, researchers said.
Six of the patients with the dysfunction before surgery, or 43 percent, died in the first year after the transplant, compared with three, or 10 percent, in the group without the dysfunction.
Infection caused the deaths of two of the six patients. Another died of massive airway bleeding, one of non-small cell lung cancer, and one of stroke. The study did not identify the sixth patient’s cause of death.
Survival in an intensive care unit or while hospitalized did not differ between the two groups in the first few weeks after a transplant. But it became significantly different later. One-year survival was much worse in patients with the heart chamber malfunction.
Another finding was that far more patients with diastolic dysfunction needed life support than those in the other group after surgery — 33 percent versus 7 percent.
Patients in the dysfunction group also had worse ICU disease severity scores and fewer ventilator-free days than those in the non-dysfunction group.
“Diastolic dysfunction has a significant negative impact on outcomes after double lung transplantation for PAH,” the researchers wrote. “In our cohort of PAH patients, left ventricular diastolic dysfunction was associated with a more complicated post-operative clinical course. This more complicated early post-operative course may have translated into worse long-term outcome.”
The team acknowledged that their study was unable to identify the reason why diastolic dysfunction was associated with poorer patient outcomes. They called for additional research on the subject.
“Diastolic dysfunction was an independent risk factor for death in the first year after transplantation,” they wrote. “The reason for this association remains speculative and requires further study.”