Detection of myocardial ischaemia using surface microdialysis on the beating heart. Clin Physiol Funct Imaging

Department of Surgical and Perioperative Sciences, Anaesthesiology and Intensive Care Medicine, University Hospital of Umeå, Umeå, Sweden.
Clinical Physiology and Functional Imaging (Impact Factor: 1.44). 11/2010; 31(3):175-81. DOI: 10.1111/j.1475-097X.2010.00995.x
Source: PubMed


Microdialysis (MD) can be used to study metabolism of the beating heart. We investigated whether microdialysis results obtained from epicardial (surface) sampling reflect acute changes in the same way as myocardial sampling from within the substance of the ventricular wall. In anaesthetized open-thorax pigs a coronary snare was placed. One microdialysis probe was placed with the sampling membrane intramyocardially (myocardial), and a second probe was placed with the sampling membrane epicardially (surface), both in the area which was made ischaemic. Ten minutes collection intervals were used for microdialysis samples. Samples from 19 pigs were analysed for lactate, glucose, pyruvate and glycerol during equilibration, baseline, ischaemia and reperfusion periods. For both probes (surface and myocardial), a total of 475 paired simultaneous samples were analysed. Results from analyses showed no differences in relative changes for glucose, lactate and glycerol during baseline, ischaemia and reperfusion. Surface microdialysis sampling is a new application of the microdialysis technique that shows promise and should be further studied.

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Available from: Anders Waldenström, Jul 25, 2014
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    • "Glucose and Glycerol reveal information regarding glucose supply and lipolysis, respectively [16]–[18]. Lactate and Pyruvate are useful to evaluate glycolysis and oxidative glucose metabolism at the tissue level [3], [4], [19]. Changes in blood flow were determined using the ethanol escape technique, and by estimation of microdialysis urea clearance [20], [21]. "
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