Ischemia-induced repolarization response in relation to the size and location of the ischemic myocardium during short-lasting coronary occlusion in humans☆
Received 3 June 2009 published online 03 December 2009.
Abstract
Background
The ventricular repolarization (VR) response to short-lasting coronary occlusion has been characterized by 3-dimensional vectorcardiography (VCG) in humans; the T vector loop becomes distorted and more circular. The purpose of this study was to relate these changes to the size of the myocardium at risk (MAR) and its location.
Methods
Continuous VCG was applied during transient coronary occlusion in 35 elective angioplasty patients, and the size of the MAR was estimated by single-photon emission computed tomography. Three VR aspects were assessed at baseline vs maximum ischemia: the ST segment, the T vector angles, and the T vector loop morphology.
Results
The T loop morphology changes were significantly associated with MAR size, but also dependent of its location. In contrast, the early phase of VR reflected by the ST segment responded to acute ischemia in relation to the MAR size independent of location.
Conclusion
The VR changes were related both to the size and the location of the MAR and most pronounced during occlusion of the left anterior descending artery.
dDepartment of Molecular and Clinical Medicine/Cardiology, Sahlgrenska University Hospital, Gothenburg, Sweden
Corresponding author. Department of Molecular and Clinical Medicine/Cardiology, Sahlgrenska University Hospital, SE-413 45 Gothenburg, Sweden.
☆ Gunilla Lundahl was, at the time of this study, a consultant to Ortivus AB, Danderyd, Sweden; and the VCG systems, which are commercially available, were a loan from Ortivus AB. There are no other disclosures to be made.
ABSTRACT