Heart rate recovery predicts clinical worsening in pulmonary hypertension

November 18, 2011

Heart rate recovery at one minute after a six-minute walking distance (6MWD) test is highly predictive of clinical worsening and time to clinical worsening in patients with idiopathic pulmonary arterial hypertension (IPAH), according to a new study.

"Ours is the first study to show that heart rate recovery at one minute of rest (HRR1) following a 6MW test is a strong predictor of clinical worsening in IPAH ," said Omar A. Minai, MD, staff physician in the Department of Pulmonary, Allergy, and Critical Care Medicine at the Cleveland Clinic. "Predicting long-term prognosis in these patients usually requires analysis of several pieces of data in complicated risk scores. This easily measured, cost-free may ultimately advance patient care in view of its ability to accurately predict clinical worsening even in patients receiving treatment for ."

The findings were published online ahead of print publication in the American Thoracic Society's .

The study enrolled 75 patients with a diagnosis of IPAH, confirmed by right heart catheterization. Heart rate was recorded at the end of the 6MW test and then one minute after completing the test. Clinical worsening was defined as any of the end points of death, , hospitalization for worsening PH, or escalation of PH therapy. The cutoff value for abnormal HRR at one minute following the 6MW test was identified as 16 beats. A greater reduction in after exercise indicates a better-conditioned heart.

"Patients with HRR1 <16 were significantly more likely to have clinical worsening events and also had significantly shorter time to clinical worsening (6.7 months versus 13 months) than those patients with HRR1≥16," according to Dr. Minai. "The odds of clinical worsening were significantly greater among patients with HRR1 <16 at all time points during follow-up."

HRR1<16 was a better predictor of clinical worsening than 6MWD alone, and when added to 6MWD improved the ability of 6MWD to predict time to clinical worsening. "HRR1<16 was also associated with known predictors of poor prognosis in IPAH," Dr. Minai added. "Patients with HRR1<16 were more likely to need supplemental oxygen during the 6MW test, be in World Health Organization functional class 4, and have more severe right ventricular dysfunction and pericardial effusion."

The study had some limitations, including its retrospective design. In addition, the time lag between right heart catheterization and the 6MW test may have biased the results, because treatment may have altered baseline hemodynamic parameters.

"HRR1 is highly predictive of clinical worsening and time to clinical worsening in patients with IPAH," concludes Dr. Minai, "and is highly correlated with known indicators of poor prognosis in these patients. Clinical worsening and time to clinical worsening have been used as end-points in a number of clinical trials in patients with IPAH. The strong predictive ability of HRR1 in these patients could make it a valuable new tool for measuring treatment response. Further study in larger prospective studies will better define its role in both IPAH and other forms of PAH."

Explore further: Cardiac rehabilitation improves heart rate recovery, boosts survival

Related Stories

Cardiac rehabilitation improves heart rate recovery, boosts survival

September 26, 2011
For the first time, researchers have discovered cardiac rehabilitation can train the heart to quickly return to its normal rate after exercise.

IPF drug fails in new trial

April 8, 2011
A new study has demonstrated no significant benefit of taking the drug bosentan for idiopathic pulmonary fibrosis (IPF).

'Walking distance' test an accurate indicator of disease severity in patients with COPD

May 16, 2011
The six-minute walking distance test (6MWD), a test that measures a patient's ability to tolerate exercise and physical activity, is an effective tool for understanding disease severity in patients with chronic obstructive ...

Recommended for you

Google searches can be used to track dengue in underdeveloped countries

July 20, 2017
An analytical tool that combines Google search data with government-provided clinical data can quickly and accurately track dengue fever in less-developed countries, according to new research published in PLOS Computational ...

MRSA emerged years before methicillin was even discovered

July 19, 2017
Methicillin resistant Staphylococcus aureus (MRSA) emerged long before the introduction of the antibiotic methicillin into clinical practice, according to a study published in the open access journal Genome Biology. It was ...

New test distinguishes Zika from similar viral infections

July 18, 2017
A new test is the best-to-date in differentiating Zika virus infections from infections caused by similar viruses. The antibody-based assay, developed by researchers at UC Berkeley and Humabs BioMed, a private biotechnology ...

'Superbugs' study reveals complex picture of E. coli bloodstream infections

July 18, 2017
The first large-scale genetic study of Escherichia coli (E. coli) cultured from patients with bloodstream infections in England showed that drug resistant 'superbugs' are not always out-competing other strains. Research by ...

Ebola virus can persist in monkeys that survived disease, even after symptoms disappear

July 17, 2017
Ebola virus infection can be detected in rhesus monkeys that survive the disease and no longer show symptoms, according to research published by Army scientists in today's online edition of the journal Nature Microbiology. ...

Mountain gorillas have herpes virus similar to that found in humans

July 13, 2017
Scientists from the University of California, Davis, have detected a herpes virus in wild mountain gorillas that is very similar to the Epstein-Barr virus in humans, according to a study published today in the journal Scientific ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.