Disproportionate systolic blood pressure response relative to oxygen consumption identifies a high-risk haemodynamic phenotype in arterial hypertension

OBJECTIVES: Conventional definitions of hypertensive response to exercise (HRE) rely on absolute systolic blood pressure (SBP) thresholds, which do not account for the metabolic demand driving the pressor response and show inconsistent association with pathophysiology and prognosis. Whether indexing SBP to oxygen consumption (VO2) provides independent pathophysiological information along the continuum from arterial hypertension (AH) to heart failure (HF) remains unclear. We investigated the haemodynamic and prognostic implications of the SBP/VO2 slope in patients with AH and preserved left ventricular ejection fraction. METHODS: We enrolled 970 participants with AH, including 34% with established HF. All subjects underwent baseline echocardiography and cardiopulmonary exercise testing with stress echocardiography. We categorized patients into tertiles of the slope of SBP relative to peak VO2 from rest to peak exercise; the highest tertile was used to define HRE for descriptive analyses. Patients were followed for all-cause mortality or HF-related hospitalisation. RESULTS: Patients with HRE (SBP/VO2 slope >5.7 mmHg/ml/kg/min) displayed adverse cardiac remodelling (higher left ventricular mass index, left atrium dilation), systemic exercise-induced vascular dysfunction (elevated peak systemic vascular resistance, reduced total arterial compliance), and reduced peripheral oxygen extraction (lower peak arteriovenous oxygen difference), despite well controlled resting BP. Over a 24-month median follow-up, a steeper SBP/VO2 slope was associated with a higher risk of death or HF-related hospitalisation, independent of peak VO2 (hazard ratio per 1-standard deviation increase: 1.21; P = 0.041). CONCLUSIONS: In patients with AH, a steeper SBP/VO2 slope identifies a high-risk haemodynamic phenotype and may represent an early marker of progression along the continuum from AH to HF.