Effects of Spinal Anaesthesia on Left Ventricular Function: An Observational Study using Two-Dimensional Strain...

Hypotension frequently occurs during spinal anaesthesia (SA), especially in the elderly. This side effect could have a cardiac component per se (myocardial contractility impairment). Two-dimensional (2D) strain and strain rate imaging are new echocardiographic methods allowing an accurate assessment of myocardial function by quantifying myocardial deformation. Allowing quantification of minor myocardial dysfunction not detectable by standard echocardiography, strain imaging could bring new perspective on the cardiac effect of SA. Our objective was to evaluate the effects of SA on left ventricular function assessed by 2D strain echocardiography.

In this prospective observational study, we enrolled 20 patients older than 60 years, who underwent elective lower-limb surgery under SA. Myocardial strain imaging were collected before and 20 minutes after SA (injection of 10 mg of isobaric bupivacaine with 5 μg of sufentanil).

We observed an increase in global longitudinal reconnoitering (Δ-0.2±0.3% s^-1; p<0.005), whereas left ventricular ejection fraction was not modified by SA.

This slight increase in myocardial contractility could be an adaptive mechanism to compensate the preload decrease and limit the blood pressure drop.