Abnormal STAT ECG Findings:

Heart Rate:

• Tachycardia (>100 bpm Adults; Pediatrics vary by age):
  • Evaluate for sinus tachycardia (fever, pain, hypovolemia) versus pathologic arrhythmias (SVT, VT, AFib).
• Bradycardia (<60 bpm Adults; Pediatrics vary by age):
  • Assess for symptomatic bradycardia, AV blocks, medication effects, or electrolyte abnormalities.
• Pediatric Considerations:
  • Recognize age-dependent normal heart rates to avoid misinterpretation:
    • Neonates (0-1 month): 90-180 bpm
    • Infants (1 month-1 year): 100-160 bpm
    • Toddlers (1-3 years): 90-150 bpm
    • Preschoolers (3-5 years): 80-140 bpm
    • School-aged (6-12 years): 70-120 bpm
    • Adolescents (13-18 years): 60-100 bpm
  • QTc abnormalities in pediatrics carry similar arrhythmogenic risks as adults and require attention

Rhythm:

• Irregular Rhythm:
  • Consider atrial fibrillation/flutter; crucial to document clearly in stroke evaluations.
• Ectopy:
  • Evaluate significance of premature atrial or ventricular complexes, considering clinical context.

Axis Deviation:

• Left Axis Deviation (LAD):
  • Suggestive of LVH, left anterior fascicular block, or inferior MI.
• Right Axis Deviation (RAD):
  • Indicates right ventricular strain (PE, COPD, pulmonary hypertension), sodium channel blocker toxicity, or hyperkalemia.

Intervals:

• PR Interval:
  • Prolonged (>200 ms): Indicates AV block or conduction delay; critical in syncope workup.
  • Short (<120 ms): Suggests pre-excitation syndromes (WPW).
• QRS Duration:
  • Wide (>120 ms): Suggests bundle branch blocks, ventricular rhythms, hyperkalemia, sodium-channel blocker toxicity.
• QTc Interval:
  • Prolonged (>500 ms): Significant risk for Torsades de Pointes.
  • Short (<350 ms): Risk factor for ventricular arrhythmias and sudden cardiac death.

Waveform Morphology:

• Q Waves:
  • Pathologic: >1 small box wide or >1/3 height of R wave, indicating prior MI.
• Poor R Wave Progression:
  • Suggests prior anterior MI or cardiomyopathy.

ST Segment:

• Elevation: Highly suggestive of acute occlusion myocardial infarction (STEMI); immediate intervention needed.
• Depression: Indicates ischemia; clinical correlation required. Depression in V1-V3 may be from Posterior STEMI.

T Waves:

• Inversion: May represent ischemia, especially if dynamic or correlating with symptoms.
• Peaked T Waves: Suggestive of acute hyperkalemia; absence reassuring in ESRD patients.

Common Pitfalls in Abnormal ECG Interpretation:

• Hidden Ischemia:
  • Normal/subtle ECG changes do not rule out ischemia. Maintain high suspicion and perform serial evaluations.
• Lead Misplacement:
  • Incorrect placement can mimic or obscure true ECG abnormalities.
• Normal Variants:
  • Recognize benign ECG patterns (e.g., early repolarization, juvenile T-wave inversions) to prevent misdiagnosis.

Key Clinical Scenarios & Documentation Tips:

• Chest Pain:
  • Clearly document presence or absence of STEMI/equivalent criteria.
• Stroke Evaluation:
  • Confirm/document absence or presence of atrial fibrillation/flutter.
• Dyspnea:
  • Clearly document right heart strain features suggestive of PE.
• Syncope:
  • Document rhythm disturbances, conduction abnormalities, prolonged intervals, epsilon waves, or ischemic changes suggestive of a cardiac cause.
• End-Stage Renal Disease:
  • Document T-wave morphology clearly to evaluate hyperkalemia risks.