학술논문

Oral Abstract session: Different imaging modalities for the approach of coronary artery disease: Friday 5 December 2014, 16:30-18:00 * Location: Agora
Document Type
Article
Source
European Journal of Echocardiography; December 2014, Vol. 15 Issue: Supplement 2 pii151-ii151, 1p
Subject
Language
ISSN
15252167; 15322114
Abstract
Background: Slow coronary flow (SCF) is a well-known clinical phenomenon, characterized by delayed opacification of coronary arteries in the absence of coronary artery stenosis. It is hypothesized that impaired endothelial function reduces coronary flow velocity reserve (CFVR), and results in microvascular ischemia causing chest pain. Also, left ventricular (LV) global longitudinal systolic strain (GLS) can be affected in this setting. The aim of this study was to: 1) evaluate how LV-GLS and CFVR are affected in patients with positive exercise tests and coronary angiograms with or without SCF. 2) examine relations between CFVR and LV-GLS. Methods: Examined group consisted of 24 female pts (mean age 58±8 years) with ECG positive exercise tests and coronary angiograms without stenosis. TIMI Flow Grade (TFG) was used as a grading system for SCF, based on the rate of dye entry into the distal landmarks of the vessel bed. According to that, examined group was subdivided into: Group 1 (7 pts with SCF (TGF<3)) and Group 2 (17 pts with TGF 3). Twenty healthy control subjects (mean age 55±9 years) were also enrolled. GLS was obtained from the three standard apical views and off-line image analysis was performed using commercial software with speckle tracking methodology derived from 2D gray-scale images. Transthoracic Doppler echocardiography CFVR was performed in left anterior descending coronary (LAD) and right coronary artery (RCA) and calculated as the ratio between hyperemic maximal flow velocity (induced with i.v. infusion of adenosine 0.14mg/kg/min) and resting flow velocity. Results Examined group compared to the control group had significantly impaired LV-GLS (-17.5±2.2 vs. -21.9±2.5, p<0.001), CFVR LAD (2.60±0.56 vs. 3.34±0.67, p<0.001) and CFVR RCA (2.48±0.42 vs. 3.20±0.64, p<0.001). Group 1 in comparison to Group 2 had lower LV-GLS (-15.9±1.3 vs. -18.2±2.2, p=0.021), CFVR LAD (2.04±0.16 vs. 2.84±0.48, p<0.001) and CFVR RCA (2.08±0.19 vs. 2.65±0.38, p=0.001). In the examined group LV-GLS correlated both with CFVR LAD (r=-0.449, p=0.028) and CFVR RCA (r=-0.514, p=0.010). Conclusions: This study shows that blunted CFVR values in SCF setting are associated with depressed LV-GLS, demonstrating an important pathophysiological link between the impairment of microcirculation and longitudinal LV systolic function.

Online Access