The role of continuous positive airway pressure in diastolic heart dysfunction

Excerpt

In their Letter to the Editor Agarwal et al. state that in patients with diastolic dysfunction the effects of positive pressure therapy compromises venous return and decreases left ventricular end diastolic volume further limiting stroke volume and hence cardiac output because of the steep curve for left ventricular diastolic pressure in relation to volume with resultant deterioration of hemodynamics. In contrast to this, the most popular studies using either continuous positive airway pressure (CPAP) or bilevel positive airway pressure (BiPAP) [1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13] report a significant reduction in endotracheal intubation rates and significant improvements in gas exchange and vital signs. Two of these studies show a reduction in mortality in patients treated with CPAP [5, 12]. In addition, a recent preliminary study [14] has demonstrated that CPAP can be used to manage acute pulmonary edema (APE) in patients with diastolic left ventricular dysfunction, and it was also suggested that the benefit of CPAP may result from a decrease in left-ventricular end-diastolic volume. Furthermore, is very likely that in all these studies almost 50% of patients admitted with a diagnosis of APE could in fact be classified as having hypertensive diastolic heart failure. …