The Clinical Value Of QRS Slope And Angle Index During Exercise Treadmill Test In The Diagnosis Of Myocardial Ischemia

Objective: To discuss the value of QRS slope and angle in diagnosing CHD by itschanges in patients of the CAG negative and positive during treadmill exercise testing.Methods: Retrospective analysis on166cases which using Bruce method to checkthe patients’s restrictive symptom in TET, these patients are suspected of havingCHD which found in CAG examination in half year.1.Having measured the slopeindex and angle of QRS complex during their movements and also observing thetiming of various parameters change with their relations, these patients have beendivided into two groups“negative and positive” according to CAG results.2.Comparing different group of patients’s slope and angle indexs and the relations toseverity of coronary arterial atherosclerosis,CAG positive groups has been dividedinto SvD, DvD and MvD.3. To analysis slope and angle index of QRS complexand the relation to lesion location of coronary artery, SvD group has been dividedinto four subgroups: A(LAD, B(LCx), C(RCA) and D(LM).4.Comparing thechanges of QRS slope and angle index in exercising testing and in the process ofCAG combining and grouping,we analyzed the sensibility of diagnosis ofmyocardial ischemia for QRS slope and angle.Results: Some patients in these166cases who have been accepted treadmill exercise andCAG,there are86CAG patients with positive whose average age27~73years old(54.58±9.10) and80patients with negative, average ages31~78years old（52.61±9.78）.The QRS slope and angle variation are very obvious after exercise in which lead Ⅱis the most stable. Comparing before and after movement of CAG positive group,some parameters of QRS slope angle“R”value increased and“U”value decreasedwhich have statistical difference（P<0.05）. other parameters haven’t statisticaldifference(P>0.05) Comparing before and after movement of CAG negative group,all parameters variation of QRS slope and angle aren’t obvious which haven’tstatistical difference（P>0.05）. the value“U”changing between coronary arterynegative groups and single-vessel disease which is statistically significant（P<0.05）and the rest of each parameter has no difference. Yet the comparison between coronary artery negative groups and double branch lesion group, thecomparison between coronary artery negative groups and three lesion group,thecomparison between double branch lesion group and three lesion group, all ofwhich these parameters are undifferentiated. Before and after movement,the angelvalue“R”changing between coronary artery negative groups and single-vesseldisease has statistical significance（P<0.05）. After the patients with left anteriordescending coronary artery lesions take exercise testing, the value R increased andU value decreased which have statistical difference（P<0.05）and other parametershave no statistical significance. Each parameter has no difference about thesensibility of left circumflex artery and right coronary artery lesions.Conclusion:1.The changes of the slope and angle in the QRS wave is the most obviousright after the movement, and the II lead is the most stablest.2.The slope and angleparameters of QRS wave group and other angle parameter values “R”、“U” can betaken as reference positive indicators in TET examination which has somesupplementary values for ST standard in exercise test, especial in reducing falsepositive rate.3.The value“R”obviously increase after single vessel diseasemovement, but it doesn’t change after double-vessel and triple-vessel diseasemovement.4. As for pathological change for left anterior descending branch, thevalue R increases and U value decreases after exercise. left circumflex artery andright coronary artery lesions have not obvious change after exercise.