[Stress echocardiography with the use of impulse wave tissue Doppler technology in diagnosis and quantitative evaluation of concealed myocardial ischemia]. / Stress-ékhokardiografiia s primeneniem tekhnologii impul'sno-volnovogo tkanevogo dopplera v diagnostike i kolichestvennoi otsenke skrytoi ishemii miokarda.

ABSTRACT

AIM: To elucidate the role of the use of impulse-wave tissue doppler technology during stress echocardiography with transesophageal atrial pacing for diagnosis and evaluation of concealed myocardial ischemia. MATERIAL: Patients (n=82, 72 men, 10 women, mean age 43+/-10 years) with syndrome of cardiac pain of obscure etiology. METHODS: Regional contractility of left ventricular wall was studied through apical approach with the use of 12-segment model. Peak systolic velocity of myocardial segments (S, cm/s), its acceleration (Asl, cm/s(2)), duration of period of preejection (PEP, ms) and isovolumic relaxation time (IVRT, ms) of each segment were calculated at rest, and during subthreshold and threshold pacing. RESULTS: Concealed myocardial ischemia was revealed by stress echo in 44 patients. Total number of analyzed segments was 984 and parameters of impulse-wave tissue doppler could be measured in 959 (97%) segments. At peak pacing rate during stress test 789 (82%) segments were normokinetic, 142 (15%) - hypokinetic, 20 (2%) - akinetic, and 8 (1%) - dyskinetic. Absence of increase or decrease of S and prolongation of PEP by 10% or more from baseline during stress test were found to be predictors of myocardial ischemia (sensitivity 35 and 75%, respectively, specificity 37 and 81%, respectively), and criteria of objectification of zones of left ventricular wall with impaired contractility (sensitivity 51 and 75%, respectively, specificity 52 and 76%, respectively). During stress echocardiography only dynamics of myocardial IVRT reflected the state of regional left ventricular diastolic function. CONCLUSION: Stress echocardiography with transesophageal atrial pacing combined with impulse-wave tissue doppler imaging is a highly informative method of diagnosis and quantitative assessment of concealed myocardial ischemia.