Relation between oscillatory breathing and cardiopulmonary function during exercise in cardiac patients.

Background: Oscillatory breathing, alternating between hyperpnea and hypopnea, has been recognized in cardiac patients, especially in those with heart failure. We evaluated whether the cycle length and amplitude of oscillatory breathing correlate with impaired cardiopulmonary function during exercise.

Methods And Results: We analyzed respiratory gas data during cardiopulmonary exercise testing (CPX) in 17 cardiac patients (68 ± 12 years) who showed clear oscillatory ventilation during CPX.

Abnormal end-tidal PO(2) and PCO(2) at the anaerobic threshold correlate well with impaired exercise gas exchange in patients with left ventricular dysfunction.

Background: The aim of the present study was to compare the end-tidal O(2) pressure (PETO(2)) to end-tidal CO(2) pressure (PETCO(2)) in cardiac patients during rest and during 2 states of exercise: at anaerobic threshold (AT) and at peak. The purpose was to see which metabolic state, PETO(2) or PETCO(2), best correlated with exercise limitation.

Methods And Results: Thirty-eight patients with left ventricular (LV) ejection fraction <40% underwent cardiopulmonary exercise testing (CPX).

Overshoot phenomenon of oxygen uptake during recovery from maximal exercise in patients with previous myocardial infarction.

The overshoot in oxygen uptake (VO2 overshoot) during recovery from maximal exercise is thought to reflect an overshoot in cardiac output. We investigated whether this phenomenon is related to cardiopulmonary function during exercise in cardiac patients. A total of 201 consecutive patients with previous myocardial infarction underwent cardiopulmonary exercise testing (CPX).

Prognostic value of end-tidal CO2 pressure during exercise in patients with left ventricular dysfunction.

We compared the prognostic power of end-tidal CO(2) pressure (PETCO(2)) during exercise, an index of arterial CO(2) pressure, with those of established respiratory gas indexes during exercise testing in patients with left ventricular dysfunction. Seventy-eight consecutive patients with a left ventricular ejection fraction (LVEF) View Article and Find Full Text PDF

Prognostic value of heart rate profiles during cardiopulmonary exercise testing in patients with cardiac disease.

Earlier studies have demonstrated that an impaired capacity to increase heart rate (HR) and a slowed HR recovery following exercise are both associated with cardiovascular mortality. We sought to determine whether HR profiles during exercise testing are superior to respiratory gas parameters in predicting mortality among patients with cardiac disease. Five-hundred and fifty stable cardiac patients (63.

Clinical significance of cerebral oxygenation during exercise in patients with coronary artery disease.

Background: Recent investigations have demonstrated that cerebral oxyhemoglobin (O(2)Hb) decreases during exercise in patients with left ventricular dysfunction, reflecting a cerebral hypoxia. We sought to establish a prognostic value of decreased cerebral O(2)Hb during exercise in cardiac patients, and to compare it with those of indexes obtained from cardiopulmonary exercise testing (CPX).

Methods And Results: A total of 344 consecutive patients with coronary artery disease were enrolled in the study.

Determination of the V.E/V.CO2 slope from a constant work-rate exercise test in cardiac patients.

Incremental exercise testing to a symptom-limited maximum has been used to measure the ratio of the increase in ventilation (V.E) to the increase in CO(2) output (V.CO(2)) during exercise (V.