Exercise intolerance in patients with heart failure and preserved left ventricular systolic function: Failure of the Frank-Starling mechanism

Abstract

Invasive cardiopulmonary exercise testing was performed in 7 patients who presented with congestive heart failure, normal left ventricular ejection fraction and no significant coronary or valvular heart disease and in 10 age-matched normal subjects. Compared with the normal subjects, patients demonstrates severe exercise intolerance with a 48% reduction in peak oxygen consumption (11.6 +/- 4.0 versus 22.7 +/- 6.1 ml/kg per min; p less than 0.001), primarily due to a 41% reduction in peak cardiac index (4.2 +/- 1.4 versus 7.1 +/- 1.1 liters/min per m2; p less than 0.001). In patients compared with normal subjects, peak left ventricular stroke volume index (34 +/- 9 versus 46 +/- 7 ml/min per m2; p less than 0.01) and end-diastolic volume index (56 +/- 14 versus 68 +/- 12 ml/min per m2; p less than 0.08) were reduced, whereas peak ejection fraction and end-systolic volume index were not different. In patients, the change in end-diastolic volume index during exercise correlated strongly with the change in stroke volume index (r = 0.97; p less than 0.0001) and cardiac index (r = 0.80; p less than 0.03). Pulmonary wedge pressure was markedly increased at peak exercise in patients compared with normal subjects (25.7 +/- 9.1 versus 7.1 +/- 4.4 mm Hg; p less than 0.0001). Patients demonstrated a shift of the left ventricular end-diastolic pressure-volume relation upward and to the left at rest. Increases in left ventricular filling pressure during exercise were not accompanied by increases in end-diastolic volume, indicating a limitation to left ventricular filling.(ABSTRACT TRUNCATED AT 250 WORDS)

Echocardiographic evaluation of diastolic heart failure

“…Only few studies have invasively assessed response to aerobic exercise; upright bicycle exercise testing with simultaneous right heart catheterisation and serial radionuclide ventriculography 161 , demonstrated that cardiac index, stroke volume index, and LVEDVI at rest were similar between HFNEF patients and controls but were lower in HFNEF patients at peak exercise. PCWP at rest was higher in HFNEF patients compared with controls and increased significantly at peak exercise.…”

Unexplained Exertional Dyspnea Caused by Low Ventricular Filling Pressures: Results from Clinical Invasive Cardiopulmonary Exercise Testing

“…When CPET is coupled with invasive hemodynamic monitoring using radial and pulmonary arterial catheters (i.e., invasive CPET [iCPET]), the presence of peripheral and central cardiovascular abnormalities can be better characterized through direct measurements of systemic and pulmonary vascular pressures and systemic and mixed venous oxygen content as well as precise estimation of cardiac output (Qt). 3 For example, these measurements have been used to characterize the exercise-induced increases in ventricular filling pressure and pulmonary arterial pressure in patients with heart failure [4][5][6][7][8] and pulmonary arterial hypertension, 9 respectively. Despite a detailed hemodynamic and metabolic evaluation, nearly 10% of symptomatic patients studied with iCPET in our laboratory had low V O 2 max and low maximum Qt (Qtmax) without a clearly identified cause.…”

Impact of left ventricular diastolic function on exercise capacity in patients with chronic mitral regurgitation: An exercise echocardiography study

“…Finally, an excessive elevation of pulmonary capillary wedge pressure during exercise is the main cardiac cause of exertional dyspnea. 27 Therefore, testing parameters that provide direct information about LV filling pressures, rather than LV relaxation rate, that is, my- Table I. Abbreviations as in Table I. ocardial velocity, may be more accurate in determining exercise capacity.…”