Risk stratification with the Haemodynamic Gain Index and peak rate-pressure product in patients with chronic heart failure undergoing treadmill exercise testing

AIMS: We recently demonstrated the combined prognostic value of the following two simple non-invasive parameters obtained from treadmill exercise testing in patients with heart failure (HF) with reduced ejection fraction: the Haemodynamic Gain Index (HGI) and peak rate-pressure product (RPP). However, their prognostic value is yet to be validated in patients with undifferentiated HF syndrome. METHODS AND RESULTS: We identified consecutive HF patients undergoing treadmill exercise testing for symptom evaluation between January 1991 and February 2015. The HGI was calculated from [(SBPpeak × heart ratepeak) - (SBPrest × heart raterest)]/(SBPrest × heart raterest), and the peak RPP was calculated from SBPpeak × heart ratepeak. Hazard ratios per standard deviation increase of the HGI and peak RPP for all-cause mortality were estimated using multivariable Cox regression models with adjustment for traditional cardiovascular risk factors and exercise-testing parameters (Chronotropic Reserve Index, estimated metabolic equivalents, abnormal heart rate recovery, and total exercise time). In our cohort of 5940 patients with symptomatic HF diagnosis with a median follow-up of 7.1 years, 2222 (37.4%) patients died. Higher values of both HGI and peak RPP were associated with a lower risk of mortality [adjusted hazard ratio per standard deviation increase 0.80 (0.73-0.88) and 0.85 (0.78-0.91), respectively, all P < 0.001]. Optimal cut-off values for HGI and peak RPP for discriminating all-cause mortality were 1.06 and 180 966, respectively. CONCLUSION: Both HGI and peak RPP are predictors of mortality in patients with chronic HF and may be tools to signal the need for advanced HF therapy evaluation.