Severity of cardiac failure from the standpoint of pulmonary circulation: studies centered on distribution of pulmonary perfusion.
In a normal man sitting upright, pulmonary perfusion is several times greater in the lower lung zone than in the upper zone. This pattern may sometimes be reversed in patients with cardiac disease. Tc99m-macro-aggregated albumin pulmonary perfusion images were computerized to isocounts area images (digital perfusion images; DPI). DPI were applied to various types of cardiac disease and patterns of DPI were divided into 4 classes according to amount of nonperfused pulmonary vascular bed. C-0; normal perfusion. C-1; decrease of nonperfused pulmonary vascular bed. C-2; disappearance of nonperfused pulmonary vascular bed. C-3; decrease of pulmonary vascular bed. In 71 patients with mitral stenosis relationships between pulmonary hemodynamics during exercise and distribution of pulmonary perfusion were studied, i.e. at rest (n = 71, mean pulmonary arterial pressure; 23 mmHg-cardiac index; 2.4 L/m) and during exercise C-0 (n = 13, 41 mmHg-5.4 L/m), C-1 (n = 17, 52 mmHg-5.2 L/m), C-2 (n = 27, 52 mmHg-4.5 L/m) and C-3 (n = 14, 65 mmHg-3.6 L/m) respectively. In patients with congestive heart failure cardiac status was classified to 4 classes according to ejection fraction and DPI. Patients with EF less than 30% and DPI more than C-2 showed high morbidity and mortality (two years mortality 47%; 27/40). Pulmonary venous pressure increases to maintain the cardiac index (Starling's law) in cases of decline in cardiac function or mitral stenosis. It was shown that increases in pulmonary venous pressure cause changes in distribution of pulmonary perfusion, which in turn works to depress the cardiac index. A decline in cardiac function and changes in the distribution of pulmonary perfusion coexist, mediated by pulmonary venous pressure and cardiac index. The distribution of pulmonary perfusion reflects the severity of cardiac failure itself, so by using DPI the severity of cardiac failure can be easily evaluated.
Tanaka
T
T
Cardiovascular Institute, Tokyo Women's Medical College, Japan.
Katou
K
K
Kimata
S
S
Hosoda
S
S
Hirosawa
K
K
D001794:Blood Pressure; D002311:Cardiomyopathy, Dilated / Q000503:physiopathology; D003327:Coronary Disease / Q000503:physiopathology; D015444:Exercise; D006333:Heart Failure / Q000000981:diagnostic imaging / Q000503:physiopathology*; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008168:Lung / Q000000981:diagnostic imaging*; D008946:Mitral Valve Stenosis / Q000503:physiopathology; D011379:Prognosis; D011651:Pulmonary Artery / Q000502:physiology; D011652:Pulmonary Circulation; D011877:Radionuclide Imaging; D013318:Stroke Volume; D013668:Technetium Tc 99m Aggregated Albumin
D013668:Technetium Tc 99m Aggregated Albumin