Stress Echocardiography by the ABCDE Protocol ln the Assessment of Prognosis of Stable Coronary Heart Disease.

AIM: To assess the role of clinical indicators and parameters of stress echocardiography performed according to an extended protocol as predictors for the occurrence of a composite cardiovascular endpoint (CCVEP) in IHD. MATERIAL AND METHODS: The study included 186 patients (60.2% men, mean age 60.6±9.9 years) with an established (n=73; 39.2%) and suspected (60.8%) diagnosis of IHD. Stress EchoCG with adenosine triphosphate (38.2%), transesophageal pacing (15.1%), dobutamine (2.6%), and bicycle ergometry on a recumbent ergometer (44.1%) was performed. The stress EchoCG protocol included assessment of regional wall motion abnormalities (WMA), B-lines, LV contractile reserve (CTR), coronary reserve (CR), and heart rate reserve. The median follow-up period was 13 [9; 20] months. The composite CCVEP included death from cardiovascular diseases and their complications, acute coronary syndrome, and revascularization and was defined at the first of these events. Statistical analysis was performed with the Statistica 16.0 and SPSS Statistics 23.0 software packages. Differences were considered statistically significant at p<0.05. RESULTS: Invasive or noninvasive coronary angiography was performed in 90.3% of patients; obstructive coronary disease (stenosis ≥50%) was detected in 67.9% of cases. During the follow-up period, 58 (31.2%) patients had cardiovascular complications. The risk of developing CCVEP was associated with the pretest probability (PTP) of ischemic heart disease (odds ratio, OR, 1.05; 95% confidence interval, CI, 1.02-1.08), dyslipidemia (DLP) (OR 0.40; 95% CI 0.20-0.82), carotid atherosclerosis (OR 0.39; 95% CI 0.18-0.86), LV ejection fraction (OR 0.96; 95% CI 0.93-0.99), appearance at peak stress of new significant (2 LV segments or more) regional WMAs (OR 0.32; 95% CI 0.18-6.55), decreased LV CTR (OR 0.46; 95% CI 0.27-0.79) and CR (OR 0.33; 95% CI 0.18-0.61); p<0.05 for all. In a multivariate analysis with Cox regression, the model with clinical indicators included PTP of IHD (OR 1.04; 95% CI 1.01-1.07; p=0.01) and DLP (OR 0.14; 95% CI 0.02-1.01; p=0.05) as predictors. The model with stress EchoCG parameters included the appearance of new significant WMAs (OR 0.33, 95% CI 0.16-0.65; p=0.001) and reduced <2.0 CR (OR 0.44; 95% CI 0.24-0.82; p=0.01). A comparative analysis of Kaplan-Meier curves confirmed statistically significant differences in the dynamics of the CCVEP occurrence depending on the absence or presence of hemodynamically significant WMAs and/or reduced CR during stress EchoCG (p<0.01). CONCLUSION: Reduced LV CR and WMA during stress EchoCG in patients with suspected or confirmed IHD are significant independent predictors for the CCVEP occurrence. Among clinical indicators, PTP of IHD and DLP are of the greatest importance for prognosis.

[Serial Assessment of Transthoracic Coronary Flow Reserve as Method of Assessing Efficacy of Intracoronary Intervention in the Left Anterior and Posterior Descending Arteries].

Transthoracic echocardiography (TTE) has been described as an accurate technique for noninvasive evaluation of coronary flow reserve (CFR) of the left anterior descending artery (LAD) and posterior descending artery (PDA). Aim of this study was to find out whether serial measurement of CFR in LAD and PDA using TTE allows detection of stenosis elimination after intracoronary intervention and is a marker of successful procedure. METHODS: The study group comprised 14 patients with single-vessel coronary disease (stenosis 82+/-14%) of the LAD (9 patients) or right coronary artery (RCA, 5 patients) scheduled for stent implantation. All patients underwent dipyridamole stress echo with CFR evaluation of either distal LAD or PDA 1 day before and 6-9 days after successful stent implantation. CFR was calculated as the ratio of hyperemic to basal peak diastolic velocity. A CFR value of <2.0 was considered abnormal. RESULTS: Adequate Doppler signals to measure CFR were obtained in 13 patients (93%). Abnormal pre-procedure CFR value was revealed in 12 assessed patients (92%). Significant increase of CFR due to a decrease of coronary flow velocity at rest and its more pronounced hyperemic rise was found in all patients after stent implantation (CFR: 1.28+/-0.52 before and 2.53+/-0.37 after stenting; p<0.001). Using a cut-off value of CFR more or equal 2.0 to identify absence of significant coronary artery disease, TTE detected successful stent implantation with a sensitivity of 91.7% and specificity of 100% for both LAD and RCA. CFR was still abnormal in only 1 patient with pre-procedure>90% LAD stenosis. CONCLUSION: TTE is a feasible technique for serial CFR evaluation in LAD and PDA. Cut-off CFR value more or equal 2.0 is a sensitive and specific criterion of successful stent implantation in LAD and RCA.

[Transthoracic dopllerographic assessment of the relative coronary reserve in the norm and in the presence of isolated hemodynamically significant stenoses of the left anterior descending coronary artery].

Comparison of velocity parameters of blood flow and absolute coronary reserve (absCR) in the left anterior descending and posterior interventricular coronary arteries (ADCA and PICA) with calculation of relative coronary reserve (relCR) and determination of its normative values was carried out with the help of transthoracic echocardiography in 29 healthy volunteers (mean age 40+/-13 years). Assessment of the role of absCR and relCR in ADCA in diagnostics of hemodynamically significant stenoses of this vessel was performed in 88 patients with syndrome of cardiac pain (mean age 40+/-12 years). Coronary angiography was used as a reference method. Coronary blood flow in distal segments of ADCA and PICA was measured at baseline and during infusion of a vasodilator (dipyridamole up to 0.84 mg/kg as intravenous infusion). AbsCR for each of these arteries was determined as ratio of hyperemic peak diastolic blood flow velocity and its baseline value. Lowering of absCR was diagnosed at its level <2.0). RelCR was calculated only for ADCA as ratio of absCR of ADCA and PICA. It was established that parameters of coronary blood flow and absCR level in healthy volunteers in ADA and PICA had no significant differences. Therefore these vessels were considered referent for each other. In the norm relCR in ADA was 1.09+/-0.36 (95% confidence interval from 0.95 to 1.23). We proved that ADA abs CR in <2.0 served as predictor of ADA stenosis >50% with sensitivity 89% and specificity 85%. However 22% of subjects with lowering of absCR had ADA stenoses <50%, microvascular involvement, or belonged to the group of healthy volunteers. It was established that ADA relCR <0.80 in patients with ADA absCR <2.0 was a sensitive and specific sign of isolated ADA stenosis >50%.

[Transesophageal and transthoracic ultrasound study of coronary arteries in diagnosis of atherosclerosis and assessment of coronary reserve].

The lecture deals with methodological aspects and diagnostic potential of the use of novel ultrasound technologies -- transesophageal and transthoracic doppler ultrasonography of coronary arteries for noninvasive assessment of coronary blood flow and coronary reserve. It contains detailed description of technique of visualization of coronary arteries from transesophageal and from transthoracic approaches and interpretation of dopplero-graphic parameters of laminar and turbulent coronary flows. Diagnostic role of the use of contrast echo imaging of coronary arteries is also discussed and dopplero-graphic criteria of occlusion and hemodynamically significant coronary artery stenosis as well as characteristics of normal and lowered coronary reserve are presented.

Simultaneous transesophageal Doppler assessment of coronary flow reserve in the left anterior descending artery and coronary sinus allows differentiation between proximal and non-proximal left anterior descending artery stenoses.

AIM AND METHODS: The role of simultaneous transesophageal Doppler assessment of coronary flow reserve (CFR) in the left anterior descending artery (LAD) and coronary sinus (CS) in the diagnostics of hemodynamically significant LAD stenoses of various localization was studied in 16 CAD patients with angiographically proven >50% stenotic atherosclerosis of the LAD (nine--in the proximal third, seven--in the mid and/or distal third) and 23 healthy volunteers (all men). Dipyridamole was used as a stress agent. The diastolic phase of coronary flow in the LAD and the antegrade phase of coronary flow in the CS were analyzed. CFR in the LAD and CS was calculated in two ways: one--as ratio of peak hyperemic flow velocity to the peak baseline blood flow velocity (CFR by Vp); two--as ratio of volume hyperemic blood flow velocity to the volume baseline blood flow velocity (CFR by VBF). The level of the CFR <2 in both ways of calculation was diagnosed as reduced. RESULTS: It was found that in CAD patients with LAD proximal stenosis the values of CFR in the LAD were significantly lower than those in healthy individuals by both Vp (1.87 +/- 0.43 and 3.54 +/- 0.82; P<0.001) and VBF (1.79 +/- 0.77 and 3.85 +/- 1.25; P<0.01). In proximal stenosis CFR in the LAD by Vp was significantly lower than that in non-proximal stenosis (1.87 +/- 0.43 and 3.31 +/- 1.44; P<0.05). Sensitivity and specificity of CFR <2 in the LAD by Vp in the diagnostics of LAD proximal stenosis were 56% and 97%, respectively; and CFR <2 in the LAD by VBF--89% and 93%, respectively. In CAD patients with both proximal and non-proximal LAD stenoses CFR in the CS by Vp was significantly lower than that in healthy volunteers and was 1.74 +/- 0.53, 1.63 +/- 0.30 and 2.56 +/- 0.87; P<0.05, respectively. Sensitivity and specificity of CFR <2 in the CS by Vp in the diagnostics of hemodynamically significant LAD stenoses were 75% and 70%, respectively. The values of CFR in the CS by VBF in CAD patients and healthy volunteers did not differ significantly. CONCLUSIONS: Thus, simultaneous evaluation of CFR in the LAD and CS makes it possible to diagnose hemodynamically significant LAD stenoses and to differentiate between proximal and non-proximal impairments.

[The role of transesophageal dopplerographical assessment of coronary reserve in coronary sinus in diagnosis of hemodynamically significant left coronary artery stenoses]. / Rol' chrespishchevodnoi dopplerograficheskoi otsenki koronarnogo rezerva v koronarnom sinuse v diagnostike gemodinamicheski znachimykh stenozov basseina levoi koronarnoi arterii.

AIM: To assess the role of estimation of coronary reserve in coronary sinus by transesophageal doppler during dipyridamole stress test for diagnosis of hemodynamically significant left coronary artery stenoses. MATERIAL: Patients with angiographically proven left coronary artery stenoses (n=29) and 25 healthy volunteers. METHODS: Coronary reserve was calculated as 1) ratio of peak to basal diastolic coronary flow velocity (V(p)CR), and 2) ratio of volume coronary blood flow velocity before and during hyperemia (VBF CR). Coronary reserve <2 was considered decreased. RESULTS: Compared with healthy subjects patients with coronary heart desease had significantly lower V(p)CR (1.67+/-0.44 and 2.56+/-0.87, respectively, p<0.001) and VBF CR (2.42+/-1.37 and 5.53+/-3.65, respectively, p<0.001). Sensitivity and specificity of coronary reserve below 2 for diagnosis of left coronary artery stenoses was 72 and 72%, respectively, for V(p)CR, and 49 and 96%, respectively, for VBF CR. VBF CR below 2 was a marker of severe double vessel left coronary artery disease. V(p)CR <2 was associated with single vessel stenoses within left coronary artery system. CONCLUSION: The use of evaluation of coronary reserve by transesophageal dopplerography for diagnosis of left coronary artery stenoses is methodologically correct. Level of coronary reserve in coronary sinus can be considered an integral parameter characterizing total left coronary artery atherosclerotic damage.

Diagnostics of main coronary artery stenoses and occlusions: multiplane transoesophageal Doppler echocardiographic assessment.

AIM AND METHODS: The possibility of using multiplane transoesophageal echocardiography (TEE) and quantitative coronary angiography (QCA) in the diagnostics of stenotic atherosclerosis of the main coronary arteries in a comparative aspect were studied in 94 patients with coronary artery disease (men, mean age 52 +/- 7 years). Coronary arteries stenoses were calculated with Doppler echocardiography using a modified continuity equation: stenosis (%)=100 x(1-prestenotic VTI(d)/stenotic VTI(d)) where prestenotic VTI(d), (cm)=diastolic velocity integral in the prestenotic zone, and stenotic VTI(d), (cm)=in the trans-stenotic zone. RESULTS: High sensitivity and specificity of TEE in the diagnostics of stenotic and occlusive atherosclerosis of coronary arteries were revealed. They measured 88% and 98% for the left main coronary artery (LMCA), 97% and 67% for the left descending artery (LDA), 95% and 92% for the circumflex artery (CX), 83% and 97% for the right coronary artery (RCA), respectively. A high correlation was found between the results of TEE and QCA in the diagnostics of coronary stenoses which were made for the LMCA (r=0.82P <0.001), LDA (r=0.84, P<0.001), CX (r=0.85,P <0.001), and RCA (r=0.84, P<0.001). We developed Doppler echocardiography criteria for haemodynamically significant stenoses of coronary arteries (>50%) according to a peak diastolic velocity of the coronary blood flow, calculated as 1.4m.s(-1)for the LMCA, 0.9m.s(-1)for the LDA, and 1.1m.s(-1)for the CX. We determined Doppler echocardiography criteria of coronary arteries occlusions such as a 'break' of colour mapping, absence of Doppler spectrum and retrograde blood flow during late diastole. CONCLUSION: Transoesophageal Doppler evaluation of coronary blood flow with application of a modified continuity equation is an accurate, non-invasive method of coronary arteries stenoses diagnostics.