February 10, 1989
View Full PaperThe limited reliability of physical signs for estimating hemodynamics in chronic heart failure
Key Result
Physical signs for elevated ventricular filling pressure had 58% sensitivity and 100% specificity, while proportional pulse pressure <25% had 91% sensitivity and 83% specificity for low cardiac index.
Study Design
Type
Observational (n=50)
Structured PICO
Does the cardiovascular physical examination accurately estimate hemodynamics in patients with chronic heart failure?
P
Population
50 patients with known chronic heart failure (ejection fraction 0.18±0.06)
I
Intervention
Cardiovascular physical examination (assessment of rales, edema, jugular venous pressure, and proportional pulse pressure)
C
Comparator
Invasive hemodynamic measurements (pulmonary capillary wedge pressure and cardiac index)
O
Outcome
Diagnostic accuracy (sensitivity and specificity) of physical signs for elevated ventricular filling pressure (PCWP ≥22 mm Hg) and decreased cardiac output (cardiac index <2.2 L/min/m²)surrogate
Physical signs of congestion have low sensitivity for detecting elevated filling pressures in chronic heart failure, but proportional pulse pressure is a reliable indicator of low cardiac index.
Main Result
Effect estimate: r=0.82
Abstract
The cardiovascular physical examination is used commonly as a basis for diagnosis and therapy in chronic heart failure, although the relationship between physical signs, increased ventricular filling pressure, and decreased cardiac output has not been established for this population. We prospectively compared physical signs with hemodynamic measurements in 50 patients with known chronic heart failure (ejection fraction,.18±.06). Rales, edema, and elevated mean jugular venous pressure were absent in 18 of 43 patients with pulmonary capillary wedge pressures greater than or equal to 22 mm Hg, for which the combination of these signs had 58% sensitivity and 100% specificity. Proportional pulse pressure correlated well with cardiac index (r=.82), and when less than 25% pulse pressure had 91% sensitivity and 83% specificity for a cardiac index less than 2.2 L/min/m2. In chronic heart failure, reliance on physical signs for elevated ventricular filling pressure might result in inadequate therapy. Conversely, the adequacy of cardiac output is assessed reliably by pulse pressure. Our results facilitate decisions regarding treatment in chronic heart failure. (JAMA1989;261:884-888)