EVALUATION OF STENOTIC LEFT main coronary ARTERY AND LEFT ANTERIOR DESCENDING CORONARY ARTERY WITH A HELP OF TRANSTHORACIC ECHOCARDIOGRAPHY

Abstract

Purpose. To detect the potential of different qualitative, semi-quantitative and quantitative transthoracic Doppler signs for successful evaluation of stenotic left main coronary artery (LMCA) and left anterior descending artery (LAD). Materials and methods. 173 patients (52±10 years; 149 men) with chest pain, sinus rhythm and scheduled quantitative coronary angiography (CAG) were evaluated at rest by non-contrast transthoracic echocardiography (TT E). LMCA and proximal (p), mid (m) and distal (d) parts of the LAD were examined. The Doppler signs of coronary stenosis >50 % were determined as follows: 1 – local Doppler aliasing with the Nyquist limit set at 60 cm/s; 2 – maximal peak diastolic velocity (Vpd) >60 cm/s; 3 – ratio of stenotic/prestenotic Vpd >2.0; 4 – stenosis >50 % according to flow continuous equation: stenosis, % = 100 × (1 – prestenotic VTId / stenotic VTId), where VTId – diastolic time velocity integral. CAG was performed within 1 week after TT E. Stenosis >50 % of diameter reduction was considered as significant. Results. Sensitivity (Sens), specificity (Sp) and diagnostic accuracy (Ac) of different Doppler stenotic signs for stenotic LMCA and LAD are presented in Table 1. Thus, TT E is a method for correct evaluation of stenotic LMCA and LAD. Quantitative ratio of stenotic to prestenotic coronary flow velocities is a more sensitive sign for detecting stenosis >50 %, than qualitative and semi-quantitative evaluation of maximal coronary flow velocity only.