12 Lead EKG GXT- Exam 3

3 main purposes of a GXT

diagnoses of CAD, prognosis of the client, and therapeutic purposes

Absolute contraindications

Acute MI, unstable angina, uncontrolled cardiac arrhythmia, endocarditis, aortic stenosis, decompensated heart failure, pulmonary embolism, myocarditis, aortic dissection, physical disability precluding safe testing

Relative contraindications

known obstructive left main coronary artery stenosis, moderate aortic stenosis, tachyarrhythmias, heart block, recent stroke, mentail impairment, resting SBP >200 or DBP >110

Treadmill uses more whole body muscle mass involvement

greater physiological max

Step Protocol

2-3 mins each stage, intensity increases 3-5 METs

Ramp Protocol

10-30 seconds, each stage, .5-1 METs (slow gradual increase)

Pre-test

12 lead ECG in supine and exercise postures as well as BP

Orthostatic hypotension

decline >20 in SBP or >10 in DBP after 3 minutes of standing

Exercise

12 lead ECG recorded during last 15 seconds of each stage and peak exercise. BP and RPE during last minute of each stage

Post test

12 lead ECG immediately after exercise every 1-2 mins for 5 mins. BP every 1-2 mins until stabilized

RPE scale

6-20

Chest pain, dyspnea, and claudication scale

1-4

Absolute Indications for termination of GXT

decrease in SBP >10 with an increase in workload with evidence of ischemia, angina, CNS symptoms, desire to stop, sustained V-tach, ST elevation

Relative indications for termination of GXT

Decrease in SBP of >10 despite increase in workload, ST displacement, arrhythmias, SpO2 <80%, SBP >250 or DBP>115

Active means

exerting themselves physically to the point of sweating at least once a week

MET

3.5 x #METs = # ml/kg/min

Positive test

signs of ischemia

Negative test

no signs of ischemia

Echocardiography

wall motion, blood perfusion, ejection fraction