Displaying 1 - 2 of 2
Background In chronic heart failure (CHF), impaired pulmonary function can independently contribute to oxygen desaturation and reduced physical activity. We investigated the effect of breathing rate on oxygen saturation and other respiratory indices.
Background—It is well established that a depressed baroreflex sensitivity may adversely influence the prognosis in patients with chronic heart failure (CHF) and in those with previous myocardial infarction.Methods and Results—We tested whether a slow breathing rate (6 breaths/min) could modify the baroreflex sensitivity in 81 patients with stable (2 weeks) CHF (age, 58Ϯ1 years; NYHA classes I [6 patients], II [33], III [27], and IV [15]) and in 21 controls. Slow breathing induced highly significant increases in baroreflex sensitivity, both in controls (from 9.4Ϯ0.7 to 13.8Ϯ1.0 ms/mm Hg, PϽ0.0025) and in CHF patients (from 5.0Ϯ0.3 to 6.1Ϯ0.5 ms/mm Hg, PϽ0.0025), which correlated with the value obtained during spontaneous breathing (rϭϩ0.202, Pϭ0.047). In addition, systolic and diastolic blood pressure decreased in CHF patients (systolic, from 117Ϯ3 to 110Ϯ4 mm Hg, Pϭ0.009; diastolic, from 62Ϯ1 to 59Ϯ1 mm Hg, Pϭ0.02).
Conclusions—These data suggest that in patients with CHF, slow breathing, in addition to improving oxygen saturation and exercise tolerance as has been previously shown, may be beneficial by increasing baroreflex sensitivity. (Circulation. 2002;105:143-145.)