ECG Report Analysis

Printed Measurements (from the ECG machine)

Machine Diagnosis (printed on report)

• Sinus Rhythm
• Prolonged P-wave

Detailed ECG Interpretation

1. Rhythm

• Normal Sinus Rhythm at 70 bpm - regular P waves before every QRS, consistent P-wave axis (~19°).

2. P-Wave (113 ms - borderline prolonged)

• Machine flags "Prolonged P-wave." At 113 ms it is near the upper limit of normal (≤120 ms).
• A widened or notched P wave (especially in lead II or biphasic in V1) suggests left atrial enlargement (LAE) or inter-atrial conduction delay.
• This is a significant finding in this female patient - warrants echocardiography to assess left atrial size and mitral valve.

3. QTc = 486 ms - PROLONGED ⚠️

• Normal QTc for females is ≤440-450 ms. A value of 486 ms is significantly prolonged.
• This is the most clinically important finding on this ECG.
• Risk: Predisposes to Torsades de Pointes (TdP) - a potentially life-threatening ventricular arrhythmia.

• Electrolyte disturbances (hypokalemia, hypomagnesemia, hypocalcemia)
• Medications (antiarrhythmics, antibiotics like azithromycin, antipsychotics, antihistamines)
• Congenital Long QT Syndrome (LQTS)
• Hypothyroidism, cardiac ischemia
• Autonomic dysfunction

4. Axis

• P/QRS/T axes of 19°/43°/17° - all within normal limits, no axis deviation.

5. No LVH

• RV5/SV1 = 1.236/0.308 mV - does not meet Sokolow-Lyon criteria for LVH.

6. ST Changes (visual assessment from waveforms)

• The waveforms across limb leads (I, II, III, aVR, aVL, aVF) and precordial leads (V1-V6) do not show obvious ST elevation or depression from the visible tracings.
• No pathological Q waves identified.

Summary Diagnosis

Recommendations

1. Urgent: Check serum electrolytes (K⁺, Mg²⁺, Ca²⁺) to rule out correctable causes of prolonged QT.
2. Review all current medications - especially any that prolong QT (use CredibleMeds list to check).
3. Echocardiogram to evaluate left atrial size (given borderline prolonged P-wave).
4. Thyroid function tests (TSH) - hypothyroidism can prolong QT.
5. Cardiology referral for Long QT management; consider Holter monitoring.
6. Avoid QT-prolonging drugs until QTc is normalized or cause is identified.

⚠️ Clinical Note: A QTc of 486 ms in a female patient is a significant finding requiring active workup. The risk of TdP increases substantially when QTc exceeds 500 ms, and this patient is approaching that threshold. This should not be dismissed.