Cardiomegaly as a possible cause of lung dysfunction in patients with heart failure.
BACKGROUND
Our hypothesis is that an enlarged heart may compete for space with the lungs, causing a restrictive pattern that is often seen in patients with chronic heart failure.


METHODS
Eighty patients with stable congestive heart failure in New York Heart Association classes II and III participated in the study. We measured cardiothoracic index (chest radiography), FEV1, vital capacity, alveolar volume, lung diffusion capacity for carbon monoxide (DLCO), and its 2 subcomponents alveolar-capillary membrane diffusion (DM), and pulmonary capillary blood volume.


RESULTS
Reliable measurements were obtained in 72 of 80 participants enrolled. Cardiothoracic index averaged 57% +/- 7%. FEV1, vital capacity, alveolar volume, DLCO, and DM were inversely related to the cardiothoracic index (r = -0.514, -0.557, -0.522, -0.475, and -0.480, respectively). However, the relations of DLCO and DM with the cardiothoracic index were lost when DLCO and DM were adjusted for alveolar volume. A significant correlation (P < .01) was found between alveolar volume and vital capacity, FEV1, and DLCO (r = 0.799, 0.705, and 0.614, respectively). At multivariate analysis, cardiothoracic index, FEV1, and pulmonary capillary blood volume were independent predictors of DLCO, whereas alveolar volume, FEV1, and left ventricular ejection fraction were independent predictors of DM.


CONCLUSIONS
Cardiac enlargement in chronic heart failure appears to be involved in causing restrictive lung pattern and a reduced alveolar volume that disturbs carbon monoxide diffusion.
Agostoni
P
P
Centro Cardiologico, Fondazione Monzino, IRCCS, Istituto di Cardiologia dell' Universita degli Studi, Milan, Italy. piergiuseppe.agostoni@cardiologicomonzino.it
Cattadori
G
G
Guazzi
M
M
Palermo
P
P
Bussotti
M
M
Marenzi
G
G
D000368:Aged; D001810:Blood Volume; D002196:Capillaries; D002199:Capillary Permeability; D002248:Carbon Monoxide; D006332:Cardiomegaly / Q000150:complications* / Q000000981:diagnostic imaging; D005260:Female; D005541:Forced Expiratory Volume; D006333:Heart Failure / Q000150:complications* / Q000000981:diagnostic imaging; D006801:Humans; D008171:Lung Diseases / Q000175:diagnosis / Q000000981:diagnostic imaging / Q000209:etiology* / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D011650:Pulmonary Alveoli / Q000098:blood supply / Q000000981:diagnostic imaging / Q000503:physiopathology; D011652:Pulmonary Circulation; D011653:Pulmonary Diffusing Capacity; D013902:Radiography, Thoracic; D013318:Stroke Volume; D014797:Vital Capacity
D002248:Carbon Monoxide