Abnormal workload-indexed blood pressure response to exercise in patients at risk of or with overt heart failure
Authors: De Biase N , Del Punta L , Balletti A , Armenia S , Buralli S , Mengozzi A , Taddei S , Metra M , Pagnesi M , Borlaug B A , Williams B , Masi S , Pugliese N R 
Published: November 2023

Abstract

Background
Conflicting evidence exists regarding the functional and prognostic significance of hypertensive response to exercise (HRE), commonly defined as peak systolic blood pressure (SBP) &gt;210 mmHg in males and &gt;190 mmHg in females. No study yet has explored the impact of sex-specific, workload-indexed HRE in patients at different stages of the heart failure (HF) spectrum, as defined by the American College of Cardiology/American Heart Association HF staging system.

Purpose
We evaluated the SBP/Workload slope during exercise across the HF spectrum and investigated the hemodynamic, functional and prognostic correlates of HRE.

Methods
Fifty-eight healthy controls, 201 subjects at risk of developing HF (HF Stages A-B), and 369 patients with a definite diagnosis of HF (Stage C) were enrolled; among the latter, 143 had preserved (HFpEF) and 226 reduced (HFrEF) left ventricular ejection fraction. All patients underwent a combined cardiopulmonary-exercise stress echocardiography test. For each patient, we recorded at least two BP measurements during exercise: the first within the first minute of exercise and the last at peak effort. The SBP/Workload slope was calculated as the difference in SBP over the corresponding increment in watts (W): (SBPpeak – SBPfirst)/(Wpeak – Wfirst). In each ACC/AHA HF Stage, we divided patients according to SBP/Workload slope tertiles; HRE was defined as the highest sex-specific SBP/Workload slope tertile. A composite of all-cause mortality and hospitalization for cardiovascular reasons was chosen as the primary outcome.

Results
The median SBP/Workload slope was 0.53 (interquartile range 0.36-0.72) mmHg/W and was steeper in women than in men in all subgroups (p&lt;0.0001). After adjusting for age and sex, SBP/Workload slope was significantly higher in Stages A-B (0.61, 0.47-0.75 mmHg/W) and HFpEF (0.63, 0.42-0.86 mmHg/W) compared to controls (0.43, 0.35-0.57 mmHg/W) and HFrEF (0.47, 0.30-0.63 mmHg/W, Figure 1). In all subgroups, patients with HRE showed significantly lower peak oxygen consumption and peripheral oxygen extraction (Table). After a median follow-up of 16 months, HRE was an independent predictor of adverse outcomes (Hazard Ratio 2.05, 95% confidence interval 1.81-5.18), while rest and peak absolute SBP values did not. Kaplan-Meier analysis confirmed a worse survival probability for patients with HRE in Stages A-B and HFpEF but not in HFrEF. After adjusting for confounding factors, the patients with the highest SBP/Workload slope had a 47% higher risk of the primary outcome than subjects in the lowest tertile (Figure 2).

Conclusions
Across the HF spectrum, patients with HRE, as evaluated by the SBP/Workload slope, present with peculiar pathophysiological features and impaired functional capacity. This is especially true for those in Stages A-B and patients with HFpEF. In these subgroups, HRE may portend an increased risk of adverse cardiovascular outcomes.SBP/workload slopesKaplan-Meier curves and Hazard Ratios