To study incidence of various conventional parameters in TMT (Chiefly ST depression)To study incidence of various conventional parameters in TMT (Chiefly ST depression)

Abstract

Background&Method: The study was done on 50 adult patients with evidence of ischaemic heart disease presenting with stable angina or with angina of effort.A preliminary consultation and a clinical evaluation were done to select the cases with special attention to drug therapy. The patient was briefed about the procedure. They were given specific instructions and asked to come on the appointment date patients were called in a fasting state (light snacks about 3 hours before the test) and without consumption of any drug. Result: Taking the ate offset as 8 mts post exercise the number of cases with early onset late offset ST segment depression was 54 per cent. In the analysis of the post exercise phase 56 per cent cases had ST segment depression persisting to beyond 8 minutes in the post exercise phase of which 16 per cent went beyond 15 minutes and 8 per cent beyond 20 minutes. The offset time varied from 1 minute post exercise to 24 minutes (mean 9.14mts±5.49 mts). The ST segment depression disappeared within 8 minutes in 28 per cent cases while the offset was 8 minutes in 16 per cent cases. In 90 per cent cases, the offset time was more was more 3 mts while in 42 per cent cases the offset time was more than 9 minutes. Conclusion: Magnitude of ST segment depression more than 2 mm 80 msec after J point has a high degree of sensitivity for detecting CAD but could not classify a patient as one having severe CAD. Onset time of ST segment depression can be influenced by many factors and is thus not a useful parameter. Offset time of ST segment depression with cut off limits at 3 mts and 6 mts is a good parameter for diagnosing MVD. ST index and ST integral are very good parameters for the detection of CAD, absolute values do not correlate with severity of CAD.