Prolonged oxygen uptake kinetics during low-intensity exercise are related to poor prognosis in patients with mild-to-moderate congestive heart failure.

Study Objective: To investigate the prognostic value of oxygen uptake (O(2)) kinetics during low-intensity exercise in patients with congestive heart failure.

Design: Prospective cohort study.

Setting: Tertiary care center.

Combining low-intensity and maximal exercise test results improves prognostic prediction in chronic heart failure.

Objectives: This study investigated the combination of maximal and low-intensity exercise testing in predicting prognosis in chronic heart failure (CHF), using one single exercise test (two-step protocol).

Background: Risk assessment based on any single factor has limited accuracy and reproducibility.

Methods: Treadmill exercise testing was performed in 202 consecutive CHF patients (174 male; mean age 52 +/- 11 years) using "breath-by-breath" gas exchange monitoring.

Interaction of sildenafil with cAMP-mediated vasodilation in vivo.

Sildenafil inhibits cGMP breakdown by phosphodiesterase 5. In vitro, increased cGMP levels inhibit cAMP breakdown by phosphodiesterase 3. It is uncertain, however, whether sildenafil increases biological effects of interventions increasing cAMP levels in vivo.

Noninvasive assessment of cardiac pumping capacity during exercise predicts prognosis in patients with congestive heart failure.

Background: Prognostic parameters in patients with congestive heart failure (CHF) are important for guiding therapeutic options. Maximal oxygen uptake (O(2)max) is a widely used parameter for prognostic assessment in patients with CHF and correlates with exercise cardiac output; however, afterload is not taken into account.

Methods: The concept of a noninvasive surrogate of cardiac power output combines exercise systolic BP (SBP), as an estimate of afterload, with O(2)max, as an estimate of exercise cardiac output neglecting preload.