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Background: There is significant uncertainty regarding the timing of onset of cardiovascular stunning after cardiac surgery. Cardiovascular stunning is affecting both contractility (Ees) and arterial load. Arterial load may be represented by arterial elastance (Ea) and participates in ventriculo-arterial coupling through the Ea/Ees ratio, giving information on efficiency and performance. An alternative approach to ventriculo-arterial interaction is oscillatory power fraction (OPF). The aim of this study was to investigate the immediate beat-to-beat effects of on-pump coronary artery bypass graft (CABG) surgery on contractility, cardiac power parameters, arterial load and ventriculo-arterial coupling as well as classical haemodynamic parameters.Methods: We included 41 patients scheduled for fast-track CABG surgery. Measurements were taken before and after cardiopulmonary bypass. A flow and pressure curve were recorded from transoesophageal pulsed wave Doppler and a radial artery catheter, respectively. This enabled the calculation of stroke work, total cardiac energy delivery, OPF and Ea/Ees ratio. Routine haemodynamic monitoring provided the classical haemodynamic parameters.Results: Immediately after cardiopulmonary bypass there was no firm evidence for alterations in contractility, stroke work, stroke volume or arterial elastance. Ea/Ees ratio and OPF remained unchanged.Conclusions: There was no evidence for clinically relevant cardiac stunning or altered arterial load immediately after cardiopulmonary bypass for CABG surgery. The unchanged Ea/Ees ratio and OPF are indicating unchanged cardiac efficiency before and after cardiopulmonary bypass. This indicates that in elective CABG patients cardiovascular stunning is perhaps a phenomenon of inflammation and not immediate ischaemia-reperfusion injury or mechanical handling. [ABSTRACT FROM AUTHOR]

Abstract: Aims: Intra-operative grading of atheromatous plaques in the ascending aorta by epiaortic ultrasound (EAU) and transesophageal echocardiography (TEE) in patients who have undergone CABG. Methods and results: Sixty patients scheduled for elective CABG were prospectively enrolled to undergo intra-operative TEE and EAU ultrasound scanning of the ascending aorta. The ascending aorta was divided into three sections; proximal, middle and distal, and four segments; anterior, posterior, medial and lateral. Degree of atherosclerosis was graded according to a modified Montgomery scale. Epiaortic ultrasound was unable to provide images for a reliable assessment in 56 areas (7.7%; 56/720) vs 322 non-visualized areas by TEE (44.7%; 298/720) (p <0.01). Out of 563 areas that scored ≥2, EAU visualized 379/720 areas (52.6%), whereas TEE visualized 184/720 areas (25.5%) (p <0.01). EAU mean scores were significantly higher for the mid (p =0.0001) and distal (p =0.05) sections and for the posterior segment (p <0.01) vs TEE. TEE had a higher mean score than EAU in the anterior segment. When all EAU areas were grouped the posterior segment reached a significantly higher mean score (p <0.01), and the anterior segment was the second mostly diseased. Conclusions: EAU is the intra-operative investigation of choice because it allowed a detailed grading of atheromatous lesions over the entire length of the ascending aorta. Accurate grading by TEE was restricted only to those areas that could be sufficiently visualized. TEE has a reduced power of investigation that limits its use, especially in the distal ascending aorta, a site of great surgical manipulation. [Copyright &y& Elsevier]