Abnormal EKG
A safe approach to the unexpected EKG finding — what’s dangerous, what’s new vs old, and what needs action now.
Learning Objectives
- 1.Approach an unexpected/abnormal EKG systematically.
- 2.Separate dangerous patterns from benign or chronic findings.
- 3.Decide what needs emergent, urgent, or routine action.
Overview
You’ll often face an abnormal EKG in an asymptomatic or minimally symptomatic patient. The questions are: is it dangerous, is it new, and does the patient have symptoms? Those three answers drive everything.
Re-read systematically
- 1.Rate, rhythm, axis, intervals (PR, QRS, QT/QTc).
- 2.Ischemia (ST/T, Q waves), chamber abnormalities.
- 3.Compare with a prior EKG — new vs old changes the urgency entirely.
- 4.Correlate with symptoms and vitals.
Common findings and what they mean
- •Atrial fibrillation/flutter — rate and anticoagulation considerations.
- •Bundle branch blocks; first-degree AV block — often chronic/benign, but new LBBB with symptoms matters.
- •LVH — chronic pressure changes; correlate with hypertension/echo.
- •Q waves / poor R-wave progression — possible prior infarct (compare old EKG).
- •Nonspecific ST-T changes — common; interpret in context.
- •PVCs/ectopy — usually benign in normal hearts; frequent/complex ectopy warrants attention.
Dangerous patterns — act now
- •STEMI / dynamic ischemic changes.
- •High-grade AV block (Mobitz II, complete) or symptomatic bradycardia.
- •Wide-complex tachycardia (assume VT).
- •Markedly prolonged QT (torsades risk); peaked T waves/widening QRS (hyperkalemia).
- •Pre-excitation (WPW), Brugada pattern, or other channelopathy clues.
Escalate immediately
A dangerous pattern — especially with symptoms or instability — goes to the physician now and activates the appropriate pathway. A benign chronic finding in an asymptomatic patient is routed routinely.
New vs old, symptomatic vs not
- •New + symptomatic → highest urgency.
- •New + asymptomatic dangerous pattern → urgent evaluation/escalation.
- •Old + stable + asymptomatic → routine follow-up/comparison.
Common beginner mistakes
- •Not comparing with a prior EKG.
- •Treating chronic LVH/old Q waves as an acute emergency (or ignoring genuinely new changes).
- •Missing hyperkalemia or long QT.
- •Over-calling nonspecific ST-T changes, or dismissing them in a symptomatic patient.
Scope note
Scope
APPs recognize and triage abnormal EKGs and escalate dangerous patterns; formal over-read and complex interpretation involve the physician.
Nurse / MA workflow connection
- •MA acquisition quality and prompt delivery of a symptomatic patient’s EKG to you are essential.
Mini cases
A routine pre-visit EKG shows new complete heart block; the patient feels lightheaded.
Action?
Show answer
New high-grade AV block with symptoms is dangerous — escalate immediately; this is a potential pacing situation, not a routine recheck.
An asymptomatic patient’s EKG shows LVH and old inferior Q waves, unchanged from a prior EKG 2 years ago.
Action?
Show answer
Stable chronic findings unchanged from prior in an asymptomatic patient — route routinely, correlate with history/echo. Comparison to the old EKG is what de-escalates this.