# Supine bicycle exercise blood pressure, heart rate and rate pressure product in patients with normal stress echocardiograms in an unselected chest pain population

## TL;DR

This study provides reference values for blood pressure, heart rate, and workload during supine bicycle stress tests in patients with normal results.

## Contribution

The study establishes sex- and age-related reference ranges for supine bicycle stress echocardiography parameters.

## Key findings

- Men had higher peak blood pressure and longer exercise time than women.
- Peak rate pressure product did not differ significantly with age despite reduced exercise time.
- Sex and age influenced physiological responses during the exercise test.

## Abstract

Reference ranges for exercise capacity during supine bicycle stress echocardiography (SBSE) are not well described. The aim of this study was to define supine bicycle exercise parameters in patients with normal stress echocardiograms in an unselected chest pain population.

260 normal SBSE tests were analysed, recording baseline and peak measurements of heart rate, systolic and diastolic blood pressure, workload in Watts, peak rate pressure product (RPP) and total exercise time during a standardised 25 W ramp protocol.

There were sex-related differences in physiological response to exercise; peak HR was lower in men than women (men 141+/- 11 bpm vs. women 145+/-11 bpm, p < 0.01) and peak blood pressure higher in men than women (men 185+/-29mmHg vs. women 169+/-30mmHg, p < 0.05). Men exercised for 20.5% longer than women with a 6.8% greater peak rate pressure product (both p < 0.05). Age was also associated with differences in peak heart rate (< 40 156 +/- 9 bpm vs. > 70 129+/-6 bpm, p < 0.05), peak systolic blood pressure (153+/-27mmHg vs. > 70 188+/-24mmHg, p < 0.05) and reduced exercise time across both sexes (< 40 609+/-158 s vs. > 70 475+/- 126 s, p < 0.05). Although exercise time reduced with age, higher peak systolic blood pressure measurements meant peak rate pressure product was not different according to age (< 40 23881 +/- 4310 vs. > 70 24343 +/- 3058, p = 0.988).

This study established reference values for systolic blood pressure, rate pressure product, workload in Watts and total exercise time during stress echocardiography using a 25 W bicycle ergometer protocol. Despite exercise time reducing with age, peak rate pressure product remains static, suggesting peak rate pressure product may be a better standardised measure of effort than exercise time alone.