Hemodynamic Evolution of Heart Failure From Hypertension: Reduced Stroke Volume Index and Increased Heart Rate

Objective: We investigated the hemodynamic evolution of heart failure (HF) from hypertension, with emphasis on indicators of systemic perfusion. Design and method: In a case-controlled paradigm, after matching for mean arterial pressure (MAP), we compared hemodynamic variables from 24-hour pulse wave analysis (Mobil-O-Graph, ARCSolver software) in at-risk controls (Stage A/B HF) and patients with history of overt (Stage C) HF. HF patients were subsequently stratified by ejection fraction (EF): low (<40%) or high (>40%). Results: Hemodynamic differences (mean +SEM) between Stage A/B (n=109) and Stage C HF (n=52) were, respectively: SVI (36.8 vs. 31.9 mL/m2, p<.001), HR (68.1 vs. 76.4 bpm, p<.001), and arterial stiffness (pulse pressure/SVI 1.47 vs. 1.65 mmHg/mL/m2 p<.05); cardiac index (CI) and total vascular resistance index (TVRI) did not differ between groups. Robust inverse SVI-HR correlations were found in both groups (SVI lower by 3 mL/m2 for each 10 beats/min HR increase), with a downward parallel shift in HF. PP/SVI was higher in high EF patients but SVI, HR, CI, and TVRI were not different between low and high EF. In a stepwise linear regression, only SVI and HR entered the predictive equation for Stage C HF. Low SVI (<35 mL/min/m2) conferred a specificity for Stage C HF of 71%; adding HR >75 bpm increased specificity to 84%. Conclusions: SVI at any given HR is predictably lower and HR is higher in Stage C HF compared to Stage A/B controls, irrespective of EF. Low 24-hour ambulatory SVI, especially when combined with high 24-hr HR, is predictive of overt HF and could help improve HF staging.