The Impact of beta blockade on the cardio-respiratory system and symptoms during exercise

Abstract

Background Beta blockers prolong life in patients with cardiovascular diseases. Negative chronotropic and inotropic effects carry the potential to adversely effect peripheral skeletal and airway smooth muscle contributing to further fatigue, dyspnea and exercise intolerance. Research questions Do beta-blockers reduce maximal power output (MPO), VO2 max, cardiorespiratory responses, increase the perceived effort required to cycle and breath during cardiopulmonary exercise tests (CPET) and limit the capacity to exercise? Methods Retrospective observational study of subjects performing CPET to capacity from 1988 to 2012. Subjects with and without beta-blockers were compared: baseline physiological characteristics, MPO, VO 2 max, heart rate max, ventilation responses and perceived exertion required to cycle and breathe (modified Borg scale). Forward stepwise linear additive regression was performed with MPO as the dependent factor with height, age, gender, muscle strength, FEV1 and DLCO as independent contributors. Results 42,771 subjects were included 7,787 were receiving beta-blocker [mean age 61 yrs, BMI 28.40 kg/m 2 , 9% airflow obstruction (FEV1/FVC<0.7)] and 34,984 were not [mean age 51yrs, BMI 27.40 kg/m 2 , 11% airflow obstruction]. Heart rate was lower by 18.2% (95% C.I. 18.15–18.38) (p<0.0001) while Oxygen pulse (VO 2 /HR) was higher by 19.5% (95% C.I. 19.3–19.7) in those receiving beta blockers. Maximum power output (MPO) was 3.3% lower in those taking beta-blockers. The perceived effort required to cycle and breathe (mBorg) was 8% lower in those taking beta-blockers. Interpretation Increases in oxygen pulse minimize the reduction in exercise intolerance and symptom handicap associated with beta-blockers.

Cardiorespiratory fitness components in relation to clinical characteristics, disease state and medication intake: A patient registry study

“…In our study, the intake of beta blockers was associated with lower CRF, which was driven by lower peak HR while peak O 2 pulse (a surrogate for peak stroke volume) and peak minute ventilation remained stable in both men and women. A decrease in exercise response upon beta blocker intake has been reported previously, as beta blockers have negative chronotropic and inotropic effects, limiting the increase in cardiac output needed during exercise (Beloka et al, 2008;Priel et al, 2021;Tesch and Kaiser, 1983). Previously, 14 healthy subjects showed a reduced exercise capacity following a 1-week intake of bisoprolol (Beloka et al, 2008).…”

Development and application of a home-based exercise program for patients with cardiovascular disease: a feasibility study

“…A blunted heart rate response during exercise CR is an important issue among patients on beta-blockers [ 20 ]. In healthy individuals, exercise can increase heart rate up to approximately 2.5-fold, whereas stroke volume increases only approximately 1-to 1.5-fold; however, these variables may vary according to age, sex, and fitness levels [ 21 ].…”

Development and application of a home-based exercise program for patients with left ventricular dysfunction: A pilot study

“…A blunted heart rate response during exercise CR is an important issue among patients on beta-blockers (20). In healthy individuals, exercise can increase heart rate up to approximately 2.5-fold, whereas stroke volume increases only approximately 1-to 1.5-fold; however, these variables may vary according to age, sex, and tness levels (21).…”