Acute myocardial ischemia monitoring before and during angioplasty by a novel vectorcardiographic parameter set

Abstract

Background: This work evaluates the vectorcardiographic dynamic changes in ischemic patients before and during Percutaneous Transluminal Coronary Angioplasty (PTCA). Methods: Four QRS-loop parameters were computed in 51 ischemic and 52 healthy subjects with the objective of assessing the vectorcardiographic differences between both groups: maximum vector magnitude (QRSmVM), planar area (QRSPA), maximum distance between centroid and loop (QRSmDCL) and perimeter (QRSP).The conventional ST-change vector magnitude (STCVM), QRS-vector difference (QRSVD) and spatial ventricular gradient (SVG) were also calculated. Results: Statistical minute-by-minute PTCA comparison against a healthy population showed that ischemic patients monitoring is greatly enhanced when all the QRS-loop parameters, in combination with the standard STCVM, QRSVD and SVG indexes, are used in the classification. Sensitivity and Specificity, in turn, reached rather high values, 95.4% and 95.2%, respectively. Conclusions: These new vectorcardiographic set of complementary QRS-loop parameters, when combined with the classics STCVM, QRSVD and SVG indexes, increase sensitivity and specificity for acute ischemia monitoring.