Step six
Step 6 in cardiac rhythm strip analysis involves examination of the S-T segment. The normal S-T segment begins at the isoelectric line. The P-R segment is used as a baseline from which to evaluate the degree of displacement of the S-T segment from the isoelectric line. S-T segment elevation or depression is considered significant if displacement is 1 mm ( one small box) or more above or be low the isoelectric line and is seen in two or more leads. ST segment depression can be an indication of myocardial ischemia,ventricular hypertrophy, bundle-branch block, or hypokalemia, or may result from digitalis administration. ST segment elevation can be an indication of acute myocardial injury,pericarditis, coronary vasospasm, ventricular aneurysm, or hyperkalemia (Huff,2006).