Background: Propofol is thought to minimally depress myocardial function, but mainly to reduce blood pressure by vasodilation. Transthoracic tissue-Doppler echocardiography (TDE) is a novel, validated method of quantifying myocardial function. It provides new insight into myocardial function by measuring myocardial motion. We examined the effects of propofol upon myocardial function by measuring changes in left ventricle function by TDE.
Methods: We assessed change in myocardial function in propofol anaesthetized ASA I patients tissue tracking displacement (TTD) before anaesthesia onset and repeated measurements after a single propofol bolus dose. Tissue tracking score (TTS), a marker of ejection fraction, was also used (n = 10).
Results: Propofol 1.5-2 mg kg(-1) significantly attenuated PSV from 5.64 (1.17) to 4.66 (0.55) cm s(-1) (P < 0.0001) and TTD from 10.2 (2.1) to 8.5 (1.4) mm (P = 0.0091), whereas TTP was unchanged [all data: mean (SD)]. TTS declined from 7.2 (1.3) to 6.1 (0.6) mm (P < 0.01). Non-invasive mean blood pressure declined 17% (P < 0.0001).
Conclusions: The results indicate that myocardial contractile function is compromised concomitantly with reduced cyclic displacement after propofol dosing. Blood pressure declined accordingly. From these results, it is impossible to ascertain whether this was secondary to reduced cardiac filling or a consequence of a direct negative inotropic action of propofol, but it represents a left-shift of the Starling curve. The novel TDE yields new information on myocardial velocities and motion.