Increased dead space ventilation mediates reduced exercise capacity in systolic heart failure

Abstract

Rationale: Patients with chronic heart failure have limited exercise capacity, which cannot be completely explained by markers of cardiac dysfunction. Reduced pulmonary diffusing capacity at rest and excessively high ventilation during exercise are common in heart failure. We hypothesized that the reduced pulmonary diffusing capacity in patients with heart failure would predict greater dead space ventilation during exercise and that this would lead to impairment in exercise capacity. Objectives: To determine the relationship between pulmonary diffusing capacity at rest and dead space ventilation during exercise, and to examine the influence of dead space ventilation on exercise in heart fail..