Invasive methods for coronary reserve measurement

During the last years, following numerous trials, the need of functional assessment of stenoses before myocardial revascularization has been established. This came to replace the subjective approach based on the so-called “oculo-stenotic” reflex of the operator. Numerous methods for coronary reserve (CR) estimation as a measure of functional significance of the lesion, have been introduced in the practice. Those methods are noninvasive and invasive. A part of them are based on the measurement of coronary flow velocity before and after hyperemic medication, other are based on the difference of arterial pressure before and after the coronary stenosis. They are divided to such with or without hyperemic medication. During the last years in the diagnostic have been used methods for functional estimation of the lesions based only on standard coronary angiography or even computerized tomography (CT). The aim of this article is to present a review of modern invasive methods for coronary reserve measurement.

Longitudinal Strain by Speckle Tracking during Dobutamine Stress Echocardiography in Suspected Coronary Arteries Disease

Background. Speckle tracking echocardiography (STE) provides valuable information about global and regional myocardial function. STE during dobutamine stress-echocardiography (DSE) enables more reliable ischemia diagnosis. The aim of the study was to evaluate STE feasibility as a DSE visualization method and its accuracy compared to coronary angiography (CAG) in the patients with moderate-to-high coronary arteries disease (CAD) risk. Methods. We prospectively examined 140 patients (84 [60.0%] men and 56 [40.0%] women) with suspected CAD in order to verify diagnosis and evaluate myocardial viability and coronary reserve. Results. Mean left ventricular ejection fraction (LVEF) was 54.4±15.8%. All the patients had normal blood pressure (BP) and heart rate (HR) during the test. There were no significant hemodynamics alterations during the test. There were no significant complications during DSE with only 15 (12.9%) cases of different relatively low grade supraventricular and ventricular arrhythmia, mainly transitory without interventions. There were 116 (82.9%) positive DSE results, of which 2 (1.72%) were false-positive. In 2 (8.3%) patients with negative DSE results, CAG revealed 1-vessel insignificant (50– 70%) lesions with developed collaterals (false-negative results). According to DSE and CAG results, 96 (82.3%) patients underwent revascularization interventions: 86 (89.6%) percutaneous coronary interventions (PCIs) and 10 (10.4%) coronary artery bypass grafting (CABG) surgery. Sensitivity and specificity of DSE with STE for primary CAD diagnosis according to the “golden standard” CAG results were 98.3% and 91.7%, respectively, with identical positive and negative predictive values and very high overall accuracy of the method (AUC = 0.98; OR = 627.0, p<0.0001). Sensitivity and specificity of DSE with STE for defining indications for intervention and revascularization were 97.9% and 91.7%, respectively, with high overall accuracy (AUC = 0.95; OR = 564.0, p<0.0001). Combined quantification of ΔGLS and ΔWMSI for primary CAD diagnosis showed significantly lower sensitivity 86.2%(p=0.0002)andspecificity80.4%(p=0.0064)withsignificantlylowerintegralmethodaccuracy(AUC0.83,p<0.0001). Conclusions. DSE with STE as a visualization method is a safe and optimal method for ischemia diagnosis and evaluation of myocardial viability and coronary reserve in patients with suspected CAD. Given the lower ΔGLS and ΔWMSI accuracy compared to integral DSE with STE result evaluation, as well as frequent GLS growth in significant number of patients with definite positive test result, authors recommend evaluating integral test result rather than strain value.

Dobutamine Stress Echocardiography with B-Mode Speckle Tracking in Patients after Acute Coronary Syndromes: Diagnostic and Prognostic Value

Background. Speckle tracking echocardiography (STE) provides valuable data on myocardial function. STE during dobutamine stress echocardiography (DSE) allows reliable myocardial ischemia diagnosis. Aim. To evaluate STE during DSE in patients with coronary artery disease (CAD) after acute coronary syndrome (ACS) and its accuracy in ischemia diagnosis, assessment of myocardial viability and coronary reserve. Methods. We examined 58 patients (55 [94,8 %] men and 3 [5,2 %] women) men) with CAD after ACS admitted to our Institute for defining indications for coronary interventions. All the patients underwent DSE with STE for longitudinal strain quantification. Results. Mean left ventricular ejection fraction (LVEF) was 52.4±5.8%. Significant CAD according to coronary angiography (CAG) prior to DSE was proved in 38 (65.5%) patients. All the patients had a history of ACS up to 12 years before the examination (38 [65.5%] patients after percutaneous coronary intervention (PCI), including 18 [31.0%] primary PCI; 9 [15.5%] patients after coronary artery bypass grafting (CABG); 3 [5.2%] after graft PCI, 1 [1.72%] patient after aortic valve replacement (AVR) with dilated cardiomyopathy (DCM) phenotype). There were no significant complications during DSE: 5 (8.6%) cases of relatively low grade transient arrhythmia with no need for intervention. As per DSE results, we performed 35 (60.3%) revascularization interventions: 31 (58.6%) PCI’s and 4 (6.9%) CABG procedures with good outcomes. It was shown that DSE with STE sensitivity and specificity were 89.7% and 94.7% (AUC 0.92), respectively, with positive and negative predictive values of 97.2% and 81.8%, respectively, with extremely high OR 157.5, p<0.0001. Combined quantification of ΔGLS and ΔWMSI showed insignificantly lower sensitivity (86.3% [p=0.57]) and specificity (87.8% [p=0.19]) vs. integral semiquantitative ischemia markers with significantly lower overall method accuracy (AUC 0.79, p=0.047). Conclusions. DSE with STE as a visualization method is a safe and optimal method for ischemia diagnosis, as well as for myocardial viability and coronary reserve assessment in patients with CAD after ACS with the aim of risk stratification and defining indications for interventions and myocardial revascularization.

SPECKLE TRACKING DOBUTAMINE STRESS ECHOCARDIOGRAPHY DIAGNOSTIC ACCURACY IN PRIMARY CORONARY ARTERIES DISEASE DIAGNOSIS

The aim of the work was to evaluate STE feasibility as DSE visualization method and its accuracy compared to coronary angiography (CAG) in the patients with moderate-tohigh coronary arteries disease (CAD) risk. Materials and methods: We prospectively examined 140 pts (84 (60.0%) men) with suspected CAD in order to verify diagnosis and evaluate myocardial viability and coronary reserve. Results: Mean LV EF was 54.4±15.8%. All pts had normal BP and HR during the test. There were no significant hemodynamics alterations during the test. There were no significant complications during DSE – 15 (12.9%) cases of different relatively low-grade supraventricular and ventricular arrhythmia, mainly transitory without interventions. There were 116 (82.9%) positive DSE results, of which 2 (1.72%) were false-positive. In 2 (8.3%) pts with negative DSE results CAG revealed 1-vessel insignificant (50 – 70%) lesions with developed collaterals (false-negative results). According to DSE and CAG results, 96 (82.3%) pts underwent revascularization interventions – 86 (89.6%) PCI’s and (10.4%) CABG surgeries. Sensitivity and specificity of DSE with STE for primary CAD diagnosis according to “golden standard” CAG results were 98.3% and 91.7%, respectively, with identical positive and negative predictive value and very high method overall accuracy (AUC = 0.98) and OR = 627.0 (p<0.0001). Sensitivity and specificity of DSE with STE for defining indications for intervention and revascularization were 97.9% and 91.7%, respectively, with high overall accuracy (AUC = 0.95; OR = 564.0, p<0.0001). Combined quantification of ΔGLS and ΔWMSI for primary CAD diagnosis showed significantly lower sensitivity 86.2% (р=0.0002) and specificity 80.4% (р=0.0064) with significantly lower integral method accuracy (AUC 0.83, р<0.0001). Conclusions: DSE with STE as a visualization method is a safe and optimal method for ischemia diagnosis and myocardial viability and coronary reserve evaluation in the pts with CAD suspicion. Given the lower ΔGLS and ΔWMSI accuracy compared to integral DSE with STE result evaluation, as well as frequent GLS growth in significant amount of patients with definite positive test result, authors recommend evaluating integral test result rather than strain value.