Left bundle branch block and syncope

Patient

87-year-old woman; admitted after two syncopes;

Trace

Sinus rhythm, left atrial enlargement (widened and fragmented P wave); left bundle branch block: QRS width > 120 ms; absence of q wave, along with wide and notched R wave in leads I, aVL, V5 and V6 with delayed intrinsicoid deflection > 60 ms; QS and rS pattern in V1 and V2; ST-segment depression and negative T wave in leads I, aVL, V5 and V6;

Exergue

The electrocardiographic signs of a left bundle branch block are: a wide QRS, a characteristic pattern in V6 (delayed intrinsicoid deflection, absence of q waves, exclusive positive deflections, frequent ST segment depression), a characteristic pattern in V1 (absence of delayed intrinsicoid deflection, an rS or QS pattern).