NHA EKG Technician (CET) — All Questions

A patient who takes digoxin has a 12-lead with scooped, downsloping ST depression in the lateral leads and a short QT interval. What does that pattern most likely represent?

• a.Ischemia of the inner layer of the lateral wall of the left ventricle
• b.Digoxin toxicity, which means the technician holds the patient's next dose
• c.The expected digoxin effect, which is reported and not interpreted✓
• d.A low potassium level producing a U wave after each T wave

Digoxin at ordinary doses changes repolarization, and the classic footprint is a sagging, scooped ST depression with a shortened QT interval, seen most easily in the leads with tall R waves. This is a drug effect rather than a sign of poisoning, and it can appear in a patient whose blood level is entirely normal, so the technician notes the finding and the medication and lets the provider read it. True toxicity announces itself with rhythm disturbances rather than with the scooped ST segment, and holding a dose is a decision for a licensed clinician, not the technician. Subendocardial ischemia usually depresses the ST segment in a flat or downsloping line without shortening the QT interval, and a low potassium level adds a U wave after the T wave instead.

Which item in a patient's history is a non-modifiable risk factor for coronary artery disease?

• a.Type 2 diabetes that is controlled with an oral medication
• b.A father who had a myocardial infarction at age forty-six✓
• c.An LDL cholesterol level above the patient's treatment goal
• d.Cigarette smoking of about half a pack on most days

Risk factors are sorted by whether treatment or behavior can change them. Age, sex, and inherited tendency cannot be changed, so a close blood relative who had an early coronary event stays on the list for life and is weighed more heavily when the relative was young. Diabetes is the trap in this set, because the diagnosis is permanent while the risk it carries is very much modifiable through glucose control, which is why it is grouped with the treatable factors. Cholesterol and smoking are the textbook modifiable factors, since both respond to treatment or to stopping. A technician does not counsel the patient about these findings but does record an accurate history.

A 74-year-old woman with long-standing diabetes is short of breath and nauseated and denies any chest pain. The provider orders a 12-lead. What is the best reason for that order?

• a.Diabetes alters the shape of the QRS complex, so a baseline tracing is needed
• b.Nausea on its own is the most common first symptom of a coronary event
• c.Older adults, women, and people with diabetes often infarct without chest pain✓
• d.Shortness of breath points away from the heart, and the tracing documents that

The crushing substernal pain that textbooks describe is the typical presentation, not the only one. Older adults, women, and people who have had diabetes for years frequently present instead with shortness of breath, fatigue, nausea, sweating, or pain in the back, jaw, or upper abdomen, and long-standing diabetes can blunt the nerve signals that would otherwise produce pain at all. That is why a tracing is obtained on this patient rather than waiting for a symptom she may never report. Nausea alone is not the most common opening symptom of a coronary event, shortness of breath does not steer suspicion away from the heart, and diabetes does not reshape the QRS complex.

A patient scheduled for a routine 12-lead has an implanted cardioverter-defibrillator under the skin of the left upper chest. How should the technician proceed?

• a.Cancel the study, because current from the EKG machine can damage an implanted device
• b.Acquire the tracing as ordered, shifting an electrode slightly if one lands on the generator, and note the device on the record✓
• c.Move all six chest electrodes to the right side of the chest to keep them clear of the device
• d.Wait until the device has been turned off in the clinic and then record the tracing

A 12-lead machine only listens; it sends no current into the patient, so recording a tracing is safe for someone with an implanted defibrillator or pacemaker. The electrode positions do not change, although one that would sit directly over the hard bulge of the generator can be moved a small distance so it lies flat on skin and makes clean contact. The presence of the device belongs on the record, because pacing spikes and the wide complexes that follow them are easy to misread when the reader does not know a device is there. Mirroring the chest leads to the right side records an entirely different set of views and would misrepresent the patient, and asking for the device to be deactivated exposes the patient to risk for no benefit.