Article Text

  1. N. Mankan1,
  2. S. Madhunapantula1,
  3. S. Banuru1,
  4. S. Islam1
  1. 1Brooklyn, NY.


Purpose of Study Multiple studies have suggested sensitivity and specificity of 65% and 85% for exercise stress tests and 89% and 65% for pharmacological stress testing. Our study was to evaluate for a correlation between the stress testing, percentage predicted maximum heart rate (PPMHR) and coronary anatomy.

Method This was a retrospective study involving all the hospital patients who had a stress test correlated with their ECGs during the period of May 2002 to May 2003. By angio-catheterizations, all stenoses > 70% were considered as significant for all the vessels except for the left main artery for which > 50% was considered significant. We also divided them into subgroups based on PPMHR as < 50, 50-85 and > 85. Thallium (Th) was used at rest and sestamibi (Tc99) was used during the stress component of the study. As per ACC/AHA classification: A = 1-vessel, no left anterior descending (LAD); B = 1-vessel, non-proximal LAD; C = 1-vessel, proximal LAD; D = 2-vessel, no LAD; E = 2-vessel, non-proximal LAD; F = 2-vessel proximal LAD; G = 3-vessel, non-proximal LAD; H = 3-vessel, proximal LAD.

Results We found 39 abnormal stress studies (19 had pharmacological [Dipyridamole] stress test and 20 had exercise induced) of which 34 were true positives, 2 inconclusive and 3 false positive. Of the 39 cases, PPMHR varied from 38-137. Metabolic equivalents (METS) achieved during exercise stress test varied from 4-14. As per ACC/AHC coronary anatomy classification, we found 7 patients with 0 vessel disease (VD); 5 patients with 1 VD (A + B + C); 11 patients with 2 VD (D + E + F) and 12 patients with 3 VD (G + H). Among the patients with PPMHR < 50, there were 6 patients (0 VD-1, 1 VD-2, 2 VD-2, 3 VD-1); with PPMHR 51-85 there were 17 patients (0 VD-3, 1 VD-1, 2 VD-5, 3 VD-8); and with > 85 PPMHR there were 12 patients (0 VD-2, 1 VD-2, 2 VD-5, 3 VD-3) and for 4 patients PPMHR was not available. Among those who underwent dipyridamole test, PPMHR < 50 was seen in 6 patients (0 VD-1, 1 VD-2, 2 VD-2, 3 VD-1); between 50-85 9 patients (0 VD-2, 1 VD-0, 2 VD-3, 3 VD-4); > 85 0 patients and for 4 patients PPMHR was unavailable. Those 20 patients who had an exercise stress test, PPMHR 50 had 0 patients; 51-85 had 8 patients (0 VD-1, 1 VD-1, 2 VD-2, 3 VD-4); and > 85 had 12 patients (0 VD-2, 1 VD-2, 2 VD-5, 3 VD-3).

Conclusion In pharmacological and exercise stress testing PPMHR is an effective non-invasive and reliable test for the diagnosis of CAD. Exercise stress testing achieves higher PPMHR than pharmacological testing. Higher sensitivity/specificity was observed with higher PPMHRs.

Statistics from

Request permissions

If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.