Evaluation of Left Ventricular Function in Anesthetized Patients Using Femoral Artery dP/dtmax

Objective: The purpose of this study was to compare dP/dtmax estimated from a femoral artery pressure tracing to left ventricular (LV) dP/dtmax during various alterations in myocardial loading and contractile function.Participants: Seventy patients scheduled for elective coronary artery bypass surgery.Methods: All patients were instrumented with a high-fidelity LV catheter, a pulmonary artery catheter, and a femoral arterial catheter. In 40 patients, hemodynamic measurements were performed before and after passive leg raising and before and after calcium administration (5 mg/kg); and in 30 other patients, hemodynamic measurements were performed before and after dobutamine infusion (5 μg/kg/min over 10 minutes).Results: LV and femoral dP/dtmax were significantly correlated (r = 0.82, p < 0.001), but femoral dP/dtmax systematically underestimated LV dP/dtmax (bias = −361 ± 96 mmHg/s). Passive leg raising induced significant increases in central venous pressure and LV end-diastolic pressure, but femoral dP/dtmax, stroke volume, and LV dP/dtmax remained unaltered. Calcium administration induced significant and marked increases in LV dP/dtmax (23% ± 9%) and femoral dP/dtmax (37% ± 14%) associated with a significant increase in stroke volume (9% ± 2%). Dobutamine infusion also induced significant and marked increases in LV dP/dtmax (25% ± 8%) and femoral dP/dtmax (35% ± 12%) associated with a significant increase in stroke volume (14% ± 3%). Overall, a very close linear relationship (r = 0.93) and a good agreement (bias = −5 ± 17 mmHg/s) were found between changes in LV dP/dtmax and changes in femoral dP/dtmax. A very close relationship was also observed between changes in LV dP/dtmax and changes in femoral dP/dtmax during each intervention (leg raising, calcium administration, and dobutamine infusion).Conclusion: Femoral dP/dtmax underestimated LV dP/dtmax, but changes in femoral dP/dtmax accurately reflected changes in LV dP/dtmax during various interventions.