Is Age-Predicted Maximal Heart Rate Applicable in Patients With Heart or Lung Disease?

Objective To compare the predicted and actual maximal heart rate (HRmax) values in the cardiopulmonary exercise test (CPET). Methods We retrospectively investigated 1,060 patients who underwent a CPET between January 2016 and April 2020 at our institution's cardiopulmonary rehabilitation center. The following patients were included: those aged >20 years, those tested with a treadmill, and those who underwent symptom-limited maximum exercise testingreaching >= 85% of the predicted HRmax (62% if taking beta-blockers) and highest respiratory exchange ratio >= 1.1. Ultimately, 827 patients were included in this study. Data on diagnosis, history of taking beta-blockers, age, body mass index (BMI), and CPET parameters were collected. Subgroup analysis was performed according to age, betablockers, BMI (low <18.5 kg/m(2), normal, and high >= 25 kg/m(2)), and risk classification. Results There was a significant difference between the actual HRmax and the predicted value (p<0.001). Betablocker administration resulted in a significant difference in the actual HRmax (p<0.001). There were significant differences in the moderate-to-high-risk and low-risk groups and the normal BMI and high BMI groups (p<0.001). There was no significant difference between the elderly and younger groups. We suggest new formulae for HRmax of cardiopulmonary patients: estimated HRmax=183-0.76xage ( the beta-blocker group) and etimated HRmax=210-0.91xage (the non-beta-blocker group). Conclusion Age-predicted HRmax was significantly different from the actual HRmax of patients with cardiopulmonary disease, especially in the beta-blocker group. For participants with high BMI and moderate-tosevere risk, the actual HRmax was significantly lower than the predicted HRmax.