Abstract
Objectives
To compare blood flow in the pulmonary microcirculation (Qp), cardiac output (Qt), the Qp/Qt ratio, and shunt blood flow (Qs) among three different age groups, healthy individuals and patients with chronic heart failure (CHF) class III. The purpose of this comparative and methodological study, utilizing equations from a mathematical model and different analytical techniques, was to objectively diagnose CHF.
Method
Experimental data obtained through various techniques from three groups of subjects were entered into equations measuring Qt (L/min), Qp (L/min), Qs (L/min), and the Qp/Qt ratio.
Results
At rest: Group I, healthy and young subjects aged 26.3 ± 4.6 years, Qp = 4.15 L/min; Group II, non-CHF normal controls aged 62.3 ± 10.3 years, Qp = 4.595 L/min; Group III, CHF patients aged 62.4 ± 8.3 years, who had New York Heart Association functional class III failure, Qp = 5.51 L/min.
During exercise: CHF patients (Group III) at 50 W during exhaustive exercise, Qp = 8.45 L/min; non-CHF normal controls (Group II) at 50 W during nonexhaustive exercise, Qp = 15.372 L/min. Group I, at 340 W during exhaustive exercise, Qp = 23.22 L/min.
Conclusions
This new diagnostic method performed an initial objective characterization of CHF class III patients, laying the foundation for an objective classification of the four classes of CHF patients and subsequent precision medicine.