A 30-year-old woman has palpitations. ECG during sinus rhythm shows a short PR interval (0.09 sec) with normal QRS morphology and no delta wave. During tachycardia, the QRS is narrow and regular at 190 bpm. What is the most likely diagnosis?
- A Lown-Ganong-Levine syndrome ✓
- B Wolff-Parkinson-White syndrome
- C Typical AVNRT
- D Atrial tachycardia
Correct answer: A. Lown-Ganong-Levine syndrome
Explanation
LGL syndrome is characterized by short PR interval with normal QRS (no delta wave) and recurrent paroxysmal SVT. WPW shows delta waves and wide QRS due to pre-excitation. Typical AVNRT has normal PR interval in sinus rhythm. LGL is associated with intranodal or paranodal bypass tracts (James fibers) that bypass the AV node without ventricular pre-excitation.
Reference: Clinical Electrocardiography, 9th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.