INTRODUCTION — The electrocardiographic diagnosis of a variety of cardiac diseases, such as ischemia or infarction, pericarditis, and conduction disturbances, is based upon certain characteristic findings. However, none of these findings alone is usually pathognomonic for a particular disease.
This topic presents a series of tables that list the major causes of a number of common findings and abnormalities [1-4]. Their differential diagnosis is discussed in detail in the appropriate topic reviews.
●Q waves (table 1).
●ST-segment elevations (table 2).
●Low QRS voltage (table 3).
●Prominent T-wave inversions (table 4).
●Tall, positive (peaked) T waves (table 5).
●Wide QRS complex (table 6). (See "Wide QRS complex tachycardias: Approach to the diagnosis".)
●Right axis deviation (table 7).
●Long QT interval (table 8). (See "Acquired long QT syndrome: Definitions, pathophysiology, and causes" and "Acquired long QT syndrome: Clinical manifestations, diagnosis, and management" and "Congenital long QT syndrome: Diagnosis".)
●Tall R wave in V1/V2 (table 9).
