Relación entre flujo coronario y viabilidad en pacientes con infarto que reciben angioplastia con stent. Análisis con guía intracoronaria Doppler

Four-dimensional speckle tracking for assessing improvement in left ventricular contractility after coronary angioplasty

The objective of the study was to identify and quantify the potential improvement of left ventricular contractility after percutaneous transluminal coronary angioplasty (PTCA) using 4-dimensional (4D) speckle tracking echocardiography (4D STE). We investigated 41 patients with coronary disease by 4D STE pre- and 24 hours postcoronarography with (n = 18) or without (n = 23) PTCA. The 4D STE visualizes in real time the myocardium strain on 2- and 4-chamber apical views and on 3 transverse views of the left ventricle. Average and total strain of the left ventricle were measured. Of the 18 PTCA patients, 15 showed significant increase in left ventricle mean (+15 ± 6) and total strain (240 ± 100), which corresponded to an increase of 93% ± 55% from precoronarography, whereas the remainder showed no change. The total strain corresponded to 33% ± 10% (before PTCA) and 59% ± 11% (post PTCA) of the estimated normal strain for each patient. Strain improved in 70% of the segment downstream from the stent, and there was a negative correlation between the amplitude of the mean and total strain improvements after 24 hours and the mean and total strain values before PTCA. In the non-PTCA group, 21 of the 23 patients showed no changes in strain, whereas 2 showed improvement. The 4D STE showed significant improvements in left ventricular contractility in more than 70% of the areas downstream from the PTCA segment. This corresponded to an increase in the initial contractility by approximately 93% ± 55%; however, the myocardium contractility remained approximately 59% of normal level. No changes were seen in patients without PTCA.