Relationship of resting hemoglobin concentration to peak oxygen uptake in heart failure patients.
Anemia is frequent in chronic heart failure (HF). To calculate what change in peak oxygen uptake ( VO(2)) should be expected in the event of changes in hemoglobin concentration, we studied the correlation between peak VO(2) and hemoglobin concentration in a large HF population. We carried out retrospective analysis of all cardiopulmonary exercise tests (CPET) performed in our HF Clinic between June 2001 and March 2009 in HF patients who had a resting hemoglobin concentration measurement taken within 7 days of the CPET. We collected 967 CPETs, 704 tests were considered maximal and analyzed. We identified 181 patients (26%) as anemic. Peak VO(2) was lower (P < 0.001) in anemic patients (971 +/- 23 ml/min) compared with nonanemic (1243 +/- 18 ml/min). The slope of the VO(2) vs. hemoglobin ratio was 109 ml/min/g/dl at peak exercise. This correlation remained significant also when several confounding variables were analyzed by multivariate analysis. As an average, each gram of hemoglobin accounts, at peak exercise, for 109 ml/min change in VO(2) which is equivalent to 0.97 ml/min/kg. Therefore, in HF patients anemia treatment should increase VO(2) by 109 ml/min for each g/dl of hemoglobin increase.
Centro Cardiologico Monzino, IRCCS, Dipartimento di Scienze Cardiovascolari, Università di Milano, Milan, Italy. piergiuseppe.agostoni@unimi.it
Piergiuseppe
P
Agostoni
Elisabetta
E
Salvioni
Chiara
C
Debenedetti
Carlo
C
Vignati
Gaia
G
Cattadori
Mauro
M
Contini
Damiano
D
Magrì
Pietro
P
Palermo
Erica
E
Gondoni
Denise
D
Brusoni
Cesare
C
Fiorentini
Anna
A
Apostolo
D015308:Anaerobic Threshold; D000740:Anemia / Q000097:blood* / Q000209:etiology; D001944:Breath Tests; D002245:Carbon Dioxide / Q000032:analysis; D002317:Cardiovascular Agents / Q000627:therapeutic use; D004562:Electrocardiography; D005080:Exercise Test; D017079:Exercise Tolerance; D005260:Female; D006333:Heart Failure / Q000097:blood* / Q000150:complications / Q000000981:diagnostic imaging / Q000188:drug therapy; D006454:Hemoglobins / Q000032:analysis*; D006801:Humans; D008297:Male; D008875:Middle Aged; D010101:Oxygen Consumption; D012189:Retrospective Studies; D013318:Stroke Volume; D014463:Ultrasonography
D002317:Cardiovascular Agents; D006454:Hemoglobins; D002245:Carbon Dioxide