Axis deviation

Patient

47-year-old patient with left ventricular noncompaction;

Trace

Sinus rhythm; complete left bundle branch block pattern (wide QRS of 142 ms, exclusive positive deflection in V6 with delayed intrinsicoid deflection, rS pattern in V1-V2); QRS axis deviated to the left (-43°; positive QRS in lead I and negative in aVF);

Patient

74-year-old woman with COPD and right heart signs (right ventricular hypertrophy);

Trace

Signs of right ventricular hypertrophy: tall R waves in V1, V2 with R/S ratio > 1; right axis deviation (160°; positive QRS in aVF and negative in lead I);

Patient

74-year-old man with severe dilated cardiomyopathy and complete atrioventricular block who underwent implantation of a biventricular ICD;

Trace

Spontaneous atrial activation and biventricular pacing; extreme-right QRS axis (+ 230°);

Exergue

An abnormal axis most often reflects the presence of an abnormal activation sequence (branch block, hemiblock, ventricular pre-excitation, etc.), a right or left ventricular hypertrophy, a congenital heart disease, a myocardial sequela or a metabolic disorder.