Exercise training regimens are safe and can improve quality of life in patients with chronic pulmonary hypertension, according to research published in Circulation: Heart Failure.
Most individuals with pulmonary hypertension refrain from exercising to avoid additional strain on the heart. These individuals have reduced pulmonary blood flow, low cardiac output, and can have skeletal muscle abnormalities that lead to impaired oxygen intake, all of which can make it harder to exercise.
Jarett D. Berry, MD, of the University of Texas Southwestern, and colleagues evaluated the safety of exercise training in patients with pulmonary hypertension by looking at the effect of exercise on peak oxygen uptake, resting pulmonary arterial systolic pressure (PASP), peak exercise heart rate, and quality of life.
In the past, clinicians have been skeptical about the use of exercise training and cardiopulmonary rehab due to concerns of exertional syncope and progressive right ventricular dysfunction with strenuous physical activity.
“Our study findings provide comprehensive evidence in favor of efficacy and safety of exercise in patients with pulmonary hypertension and highlight its potential role as an adjunct to medical therapy designed to alleviate symptoms in patients with pulmonary hypertension,” the researchers wrote.
In a meta-analysis of 16 studies involving 434 patients with chronic pulmonary hypertension, exercise training was associated with improved exercise capacity and cardiorespiratory fitness. The median duration of each study analyzed was approximately 15 weeks. Six of the studies were parallel group trials with an intervention and control group and 10 were pre-post studies.
The researchers extracted data from the studies using a standardized questionnaire to record the six-minute walking distances, peak oxygen uptake, and SF-36 questionnaire score at baseline and during follow-up. The researchers measured quality of life based on participant’s questionnaire subscale scores and exercise capacity using the six-minute walking distance from baseline to follow-up.
The participants took part in low workload aerobic training exercises with some resistance and respiratory training. The maximum exercise intensity peaked at 60% to 80% for most studies. Each participant was assessed for exercise capacity and cardiorespiratory fitness at baseline and again at the end of the study.
The majority of the participants across the studies had Class I pulmonary hypertension (73.8%) although there were some with Class IV (20.4%), Class II (1.9%) related to left heart disease, and Class III (3.4%) secondary to chronic lung disease.
The mean six-minute walking distance at baseline was 414.3 m, and the weighted mean difference was 57.7 m at follow-up. The parallel intervention and control groups were also analyzed separately, where the training participants had a greater mean difference than the control participants (67.8 m).
Across eight of the studies, the peak heart rate among the participants improved significantly with exercise training by an average 10.4 beats per minute. These studies also reported that exercise training was associated with a significant change in oxygen uptake, with a weighted mean difference of 1.7 ml/kg/min.
Seven studies measure the effects of exercise training on resting pulmonary arterial systolic pressure, and found that exercise training improved resting pulmonary artery systolic pressure from baseline to follow-up, with a weighted mean difference of -3.6 mmHg.
Dizziness, pre-syncope, syncope or palpitations were observed in 5.5% of participants, only half of which were related to the exercise training. Respiratory and non-respiratory infections occurred in 6.7% of participants.
“The rate of major adverse events such as right heart failure, mortality, worsening pulmonary hypertension observed on pooled analysis was much lower than reported in pulmonary hypertension-specific pharmacotherapy trials,” the researchers concluded.