HEMODYNAMIC MONITORING DURING DOBUTAMINE STRESS ECHOCARDIOGRAPHY WITHIMPEDANCE CARDIOGRAPHY

Purpose: Dobutamine stress echocardiography (DSE) has become a well es tablished method for the diagnosis of coronary artery disease (CAD). H owever, little is known about the haemodynamic effects caused by the s hort-term, high dose dobutamine infusions used in DSE. The aim of our study was therefore to investigate the alterations of stroke volume (S V), cardiac output (CO) and systemic vascular resistance (SVR) in pati ents (PTS:) during DSE by impedance cardiography (ICG), a noninvasive method for continuous monitoring of haemodynamic parameters. Methods: 50 PTS who underwent DSE for suspected CAD were monitored by an automa ted impedance cardiography (ICG) system. After completion of the proto col, PTS were divided into two groups, depending on the positive (path ologic, abnormal) or negative (normal) result of the DSE-test, Mean va lues of HR, SV, CO and SVR were automatically calculated by the ICG-sy stem for each group, Baseline and peak stress values as well as the re lative changes (in % increase from baseline to peak stress) of each pa rameter mere compared within and between the two groups. Results: Ther e were significant differences (p < 0.01) in the dobutamine-induced in crease of SV (45.7 +/- 16.8% vs. 28.8 +/- 9.4%) and CO (112.4 +/- 42.8 % vs. 57.4 +/- 12.6%) between PTS with a positive (n = 24) or negative (n = 23) DSE test. No significant differences could he detected in th e increase of HR, blood pressure or SVRI, In three PTS no adequate ICG -signals could be recorded.Conclusions: Automated ICG is a feasible me thod for monitoring haemodynamic parameters during DSE, PTS with a pat hologic DSE-test show a significantly smaller increase of SV and CO in dicating ischaemic ventricular dysfunction. The results of our study d emonstrate that haemodynamic monitoring during DSE by ICG can provide additional diagnostic information concerning left ventricular function during cardiovascular stress.