Doppler echocardiography during transesophageal atrial pacing in the detection of coronary artery disease. Stress Doppler echocardiography in the detection of coronary artery disease.

The aim of this study was to assess the applicability of the Doppler echocardiogram (EchoKG) during transesophageal atrial pacing (TAP) with respect to the detection of coronary artery disease (CAD). Aortic flow peak velocity (PV), mean acceleration (MA), stroke distance (SD), minute distance (MD) and time to PV were measured using pulsed Doppler EchoKG during sinus rhythm and at pacing rates of 120 and 140 bpm in 11 patients, taken as subjects, with CAD defined by coronary arteriography and 15 patients without CAD (the control group). Similar changes of PV, SD, MD and time to PV during TAP were observed in subjects with and without CAD. Only changes of MA were different between subjects with and without CAD:MA during TAP remained unchanged in the control group and decreased from 1055.2 +/- 49.7 cm/s2 (baseline) to 829.0 +/- 55.9 cm/s2 at pacing rate 140 bpm (p < 0.05) in subjects with CAD. On the basis of these data we suggest a new criterion for the detection of hemodynamically significant CAD: decrease of MA at a pacing rate of 140 bpm > 15% of initial value. Its specificity and sensitivity in the detection of CAD were respectively 87% and 82%. We conclude that the Doppler EchoKG during TAP is a relatively simple and reliable method for the diagnosis of CAD, and that the response of the Doppler EchoKG parameter of MA to TAP is a sensitive and specific index, useful for the detection of significant coronary artery stenosis.

R wave amplitude changes during transoesophageal atrial pacing in patients with chronic ischaemic heart disease.

15 patients with intact coronary arteries (control group) and 49 patients with coronary stenosis were for the purpose of differential diagnosis of ischaemic heart disease [IHD] subjected to coronarography, left ventriculography and transesophageal atrial pacing. The possibility of using the sum R wave amplitude as a criterion of IHD was assessed, as well as the relation between the R wave amplitude and the left ventricular function indicators--the ejection fraction and the end-diastolic volume. It was found that the increase of the R wave amplitude has distinctly lower specificity (40%) and sensitivity (29%) than the ischaemic depression of the ST segment (73 and 74% respectively). No correlation was found between R wave amplitude changes and indicators of the left ventricular function. The increase in the R wave amplitude cannot be therefore regarded as a reliable criterion of IHD and is not a reflection of the functional state of the left ventricle.