Slow breathing increases arterial baroreflex sensitivity in patients with chronic heart failure.
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.


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, 58+/-1 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 9.4+/-0.7 to 13.8+/-1.0 ms/mm Hg, P<0.0025) and in CHF patients (from 5.0+/-0.3 to 6.1+/-0.5 ms/mm Hg, P<0.0025), which correlated with the value obtained during spontaneous breathing (r=+0.202, P=0.047). In addition, systolic and diastolic blood pressure decreased in CHF patients (systolic, from 117+/-3 to 110+/-4 mm Hg, P=0.009; diastolic, from 62+/-1 to 59+/-1 mm Hg, P=0.02).


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.
Bernardi
Luciano
L
Department of Internal Medicine, University of Pavia and IRCCS Ospedale S Matteo, Pavia, Italy. lbern1ps@unipv.it
Porta
Cesare
C
Spicuzza
Lucia
L
Bellwon
Jerzy
J
Spadacini
Giammario
G
Frey
Axel W
AW
Yeung
Leata Y C
LY
Sanderson
John E
JE
Pedretti
Roberto
R
Tramarin
Roberto
R
D001158:Arteries / Q000503:physiopathology; D017704:Baroreflex; D001794:Blood Pressure; D001945:Breathing Exercises; D002908:Chronic Disease; D006333:Heart Failure / Q000503:physiopathology / Q000628:therapy*; D006801:Humans; D007700:Kinetics; D008875:Middle Aged; D012119:Respiration