Cardiac function index measured using transpulmonary thermodilution

Abstract

Cardiac function index (CFI) provided by transpulmonary thermodilution (Picco system) might be a reliable indicator of left ventricular systolic ejection function (LVEF), usually assessed by echocardiography. Two studies have tested the ability of CFI to detect a left ventricular dysfunction: the results have shown that CFI was correlated with LVEF, was not altered with fluid expansion, and increased with inotropic drug infusion. CFI ≤ 4.1/min suggested LVEF < 45%, whereas CFI ≤ 3.2/min predicted LVEF < 35%. However, CFI reflects global myocardial function. A right ventricular dilatation may underestimate CFI and therefore LVEF. Since CFI is the ratio between cardiac output and global end diastolic volume, a marked atrial dilatation (such as in permanent atrial fibrillation) might also underestimate CFI and LVEF. Thus, echocardiography must be performed every time the CFI value is decreased, in order to exclude a right ventricular dilatation. CFI provided by transpulmonary thermodilution is a reliable indicator of left ventricular systolic function. CFI is able to detect a myocardial dysfunction and to monitor changes in LVEF caused by inotropic drugs.