Document Type

Conference Proceeding

Publication Date

9-21-2022

Publication Title

American Association of Cardiac and Pulmonary Physical Therapy Annual Meeting

Medical Subject Headings

Electrocardiography, Myocardial Ischemia, Coronary Artery Disease, Physical Therapy Specialty, Literature Review, Female, Humans

Abstract

Purpose: The purpose of this study is to guide physical therapists in recognizing ischemia using electrocardiogram strips during graded exercise stress testing using methods other than relying on ST segment deviation for cardiac ischemia detection.

Methods: A literature review of the English-language literature published between 1975 to 2022 on the detection and prediction accuracy of ECG abnormalities on cardiac ischemia during GXT was conducted using PubMed and CINAHL. Inclusion criteria included studies utilizing 12-lead ECG monitoring while performing GXT for the detection of cardiac ischemia. Exclusion criteria included studies that did not utilize GXT or ECG for detection of cardiac ischemia.

Results:

ECG Abnormalities

ST-deviation

  • ST deviation detection provides sensitivity ranging from 44- 71%.18
  • ST-segment deviation presentation has been shown to be a late sign of cardiac ischemia as most patients present with a main artery occlusion of 70% or higher after a positive stress test has been diagnosed.9,16,21

P-wave

  • P-wave duration showed detection improvement in women from 29% to 64%.16
  • Additionally, when P wave duration and ST-segment change were combined, sensitivity increased to 79%.16
  • P-wave amplitude measured at rest and at 50% of exercise intensity increased the detection of coronary artery disease to a sensitivity of 69% and a specificity of 78%.9
  • Combining P-wave amplitude and duration was shown to be statistically significant at 0.001 during every minute of recovery for the detection of CAD.21
  • Combining ST-segment deviation, angina, and P-wave duration change increased sensitivity to 100% compared to ST-segment and angina at 57% or P-wave duration at 69%.21

R-wave

  • R wave amplitude correction further increased the detection of ST depression with a localization of 52%-86%.27
  • Left main coronary artery disease localization was improved from 40% to 100% and left circumflex coronary artery disease localization was improved from 0% to 83% with the inclusion of R-wave amplitude correction.6,13,27

T-wave

  • T-wave changes combined with ST deviation increased specificity from 22% to 97% for CAD location.11,15,17,25,28,29

U-wave

  • Exercise-induced U waves in precordial leads have been correlated with anterior myocardial ischemia as well as highly predictive for severe disease of the LAD artery.20

Conclusion: In combination with GXT and ST-segment deviation, P-wave duration and magnitude, R-wave amplitude and progression, peaked T-waves, and presentation of inverted U-waves have all shown promise to being effective additive or alternative methods for cardiac ischemia detection.

Comments

Poster presented at the American Association of Cardiac and Pulmonary Rehabilitation Annual Meeting, held September 21-23, 2022, in West Palm Beach, Florida.

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