The cardiac response to exercise in cirrhosis.
BACKGROUND
Impaired exercise capacity and oxygen consumption are common in cirrhosis.


OBJECTIVE
To explore the relationship between possible myocardial dysfunction and exercise tolerance in cirrhosis.


METHODS
Cardiac responses to exercise, using radionuclide angiography and graded upright cycle ergometry with oxygen consumption, were assessed before and after exercise in 39 cirrhotics patients and compared with 12 age and sex matched healthy volunteers. Baseline cardiac chamber dimensions and wall thickness, ejection fraction, and diastolic function were measured using two dimensional echocardiography is all subjects.


RESULTS
Baseline diastolic dysfunction with prolonged isovolumic relaxation times (p=0.02), left atrial enlargement, and left ventricular wall thickening were present in all cirrhotics (p=0.02), despite increased mean ejection fraction. With graded exercise, cirrhotics achieved 71 (4)% (p=0.03) (pre-ascitics) and 46 (3)% (p<0.001) (ascitics) of predicted work loads, respectively, without significant increases in ejection fraction. The smaller absolute and percentage increases in cardiac output (p=0.003) in the cirrhotics were associated with significantly reduced oxygen consumption (p=0.003) and anaerobic threshold (p<0.001), and correlated significantly with work and metabolic parameters.


CONCLUSIONS
Impaired exercise capacity in cirrhosis is associated with myocardial thickening and ventricular stiffness leading to decreased diastolic function, inotropic and chronotropic incompetence under conditions of stress, with metabolic consequences. This picture is compatible with the condition now known as cirrhotic cardiomyopathy.
Wong
F
F
Division of Gastroenterology, Toronto General Hospital, University of Toronto, Ontario, Canada. florence.wong@utoronto.ca
Girgrah
N
N
Graba
J
J
Allidina
Y
Y
Liu
P
P
Blendis
L
L
D000704:Analysis of Variance; D001201:Ascites / Q000000981:diagnostic imaging / Q000209:etiology / Q000503:physiopathology; D009202:Cardiomyopathies / Q000000981:diagnostic imaging / Q000209:etiology / Q000503:physiopathology*; D016022:Case-Control Studies; D004452:Echocardiography; D005080:Exercise Test / Q000379:methods; D017079:Exercise Tolerance / Q000502:physiology*; D005260:Female; D006801:Humans; D008103:Liver Cirrhosis / Q000150:complications / Q000000981:diagnostic imaging / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D010101:Oxygen Consumption / Q000502:physiology; D011877:Radionuclide Imaging; D019275:Radiopharmaceuticals; D012044:Regression Analysis; D013670:Sodium Pertechnetate Tc 99m; D013318:Stroke Volume
D019275:Radiopharmaceuticals; D013670:Sodium Pertechnetate Tc 99m