Electroanatomic scar and myocardial atrophy in arrhythmogenic cardiomyopathy – review of ECG criteria

Electroanatomic scar and myocardial atrophy is the predominant finding of arrhythmogenic cardiomyopathy in either dominant right ventricular, biventricular of dominant left ventricular abnormalities. Lead aVR can describe electroanatomic scar by large Q waves and myocardial atrophy by small R waves. With these two conditions T wave is predominantly negative </= 2mm or in few cases biphasic.

Method: A large collective of patients 487 patients (309 males, mean age 42.2 ± 12.8 years) including own patients (436 cases), heart transplantation candidates with desmoglein-2 and plakophilin-2 mutations (41 cases), a large family (6 cases) with non compaction left ventricle and typical histologic arrhythmogenic cardiomyopathy of the right ventricle in FHL1 mutation, and 4 cases with filamin C mutations were analysed by right precordial negative T waves, epsilon waves, localised right precordial QRS prolongation, terminal activation delay, low voltage in limb leads, inferolateral T-inversions or flattening and typical findings in lead aVR.

Results: The most common electrocardiographic findings were large Q waves and small R waves in lead aVR defining electroanatomic scar and myocardial atrophy (100%). Localised right precordial QRS prolongation and terminal activation delay were found in 98%. Right precordial T-wave inversions were present of 69% of cases and epsilon waves in 30% of cases. In 7 cases low voltage in limb leads and inferolateral negative or flattened T waves were present. In the large family with FHL1 mutation and in two cases of the own patients only typical ECG signs in lead aVR were present.

Conclusion: The most common electrocardiographic finding in arrhythmogenic cardiomyopathy are large Q waves and small R waves in lead aVR closely followed by localised right precordial QRS prolongation and terminal activation delay.

These two criteria should belong to major diagnostic criteria for the electrocardiographic diagnosis of arrhythmogenic cardiomyopathy.