Researchers find new way to measure
heart function of pulmonary hypertension patients.
Researchers have developed a simple, noninvasive way
to measure right ventricular function in the heart to
predict survival of adults who suffer from pulmonary
hypertension.
The research appears in the first issue for November
2006 of the American Journal of Respiratory and Critical
Care Medicine, published by the American Thoracic Society.
Paul M. Hassoun, M.D., of the Divisions of Cardiology,
Pulmonary and Critical Care Medicine at Johns Hopkins
Hospital in Baltimore, and 11 associates studied 63
consecutive patients with pulmonary hypertension. After
right heart catheterization, these patients underwent
a transthoracic echocardiogram to assess right ventricular
performance in the heart.
Study participants were mostly female, white and had
an average age of 55. Seventy-five percent (47 patients)
met the World Health Organization's group 1 diagnostic
classification of pulmonary hypertension.
Pulmonary hypertension involves progressive narrowing
of the blood vessels in the lungs, which can lead to
death. In 2000, 163,000 patients discharged from U.S.
hospitals had been diagnosed with primary pulmonary
hypertension. Although the problem is difficult to detect
in a routine medical exam, doctors see more rapid clinical
deterioration in patients who have the greatest degree
of right ventricular dysfunction.
To assess the problem, researchers performed a test
called tricuspid annular plane systolic excursion (TAPSE),
which measures echocardiographic abnormalities in the
tricuspid valve. Located between the heart's right atrium
and right ventricle, the valve prevents the backflow
of blood as it is pumped from the right atrium to the
right ventricle.
"We found that a TAPSE of less than 1.8 cm was
associated with a greater ventricular systolic dysfunction,
as well as right heart remodeling," said Dr. Hassoun.
"In addition, survival estimates at one and two
years for those with pulmonary arterial hypertension
were 94 percent and 88 percent, respectively, for individuals
with a TAPSE of 1.8 cm or greater. If the TAPSE was
less, the survival rates were 60 percent at one year
and 50 percent at two years."
The researchers said that patients with a TAPSE of
less than 1.8 cm, showing more advanced right ventricular
dysfunction, had a dramatically reduced survival rate
over the average follow-up time of 19 months. Patients
with a TAPSE of less than 1.5 cm had an especially poor
outcome.
"Our results suggest that TAPSE is a robust measure
of right ventricular function and a powerful predictor
of patient survival in pulmonary hypertension,"
said Dr. Hassoun.
The investigators noted that they believed the TAPSE
test should be incorporated into the echocardiographic
assessment of all patients were pulmonary artery hypertension. |