Background-The cardiac output (CO) response to exercise and other invasively derived hemodynamic variables has been variably described to provide better prognostication than peak VO 2 in patients with chronic heart failure. Using noninvasive measurements of CO during exercise, we compared the prognostic value of peak CO and cardiac power to peak VO 2 in chronic heart failure patients. Method and Results-One hundred seventy-one consecutive patients with chronic heart failure underwent symptom limited bicycle exercise with noninvasive estimation of CO using an inert gas rebreathing method. An accurate measure of peak CO was obtained in 148 patients (85% of patients; mean age, 53Ϯ14 years; 80% male; left ventricular ejection fraction, 24Ϯ12%; ischemic etiology, 34%). Peak cardiac power was derived from the product of the peak mean arterial blood pressure and CO divided by 451. End points consisted of death, urgent heart transplant, or left ventricular assist device implantation. Duration of follow-up averaged 337Ϯ252 days (median, 295 days). Univariate and multivariate analysis were performed. The variables analyzed included peak VO 2 , peak CO, peak cardiac power, VE/VCO 2 slope, and VO 2 at anaerobic threshold. Event-free survival for the entire cohort was 83% with 5 deaths, 4 left ventricular assist device implants, and 16 urgent transplants. Peak VO 2 was 12.9Ϯ4.5 mL/kg per min, and peak cardiac power was 1.7Ϯ0.9 W. Peak VO 2 , peak CO, peak cardiac power, VE/VCO 2 slope, and VO 2 at anaerobic threshold were predictive of outcome on univariate analysis. On multivariate analysis, peak cardiac power and peak CO were predictive of outcome with peak cardiac power being the most powerful independent predictor of outcome (Pϭ0.01). Conclusions-Peak cardiac power, measured noninvasively, is an independent predictor of outcome that can enhance the prognostic power of peak VO 2 in the evaluation of patients with heart failure. (Circ Heart Fail. 2009;2:33-38.)

The reference ranges presented for the TDI parameters of Sa velocity, Ea velocity, and E/Ea ratio will help to standardize the assessment of LV function by tissue Doppler echocardiography.

Compared to European white people, Indian Asians had attenuated longitudinal LV function, higher LV filling pressure and demonstrated a greater degree of concentric remodelling independent of other demographic and clinical parameters.

These reference values are based on the largest 3DE study performed to date that should facilitate the standardization of the technique and encourage its adoption for the routine assessment of LV volumes and LVEF in the clinical echocardiography laboratory. This study supports the application of ethnicity-specific reference values for indexed LV volumes.

This large observational study suggests that ACEI/ARB therapy is associated with an improved survival and a lower risk of CV events in patients with AS.