A meta-analysis of ECG abnormalities (arrhythmia) in cardiomyopathies

An electrocardiogram (ECG) is an important diagnostic test recommended for individuals with a clinical suspicion of heart disease. The primary diagnostic role is the assessment of the strength and time of electrical activity in the heart. It is also the most common test for the diagnosis of arrhythmias, which are disturbances in the heart rhythm and rate. An ECG test is recommended for patients with cardiomyopathy (CM) and heart failure (HF). The two are distinct but related cardiac disease entities, in which HF is the final sequelae to CM, which is a progressive heart muscle disease. Although arrhythmias are prevalent in both CM and HF, fewer studies have investigated them as the primary objective. In the present pooled analysis of 66 studies (HF=26; CM=40). Atrial fibrillation (AF), ventricular tachycardia (VT) and premature ventricular contractions (PVC) are the most common arrhythmias. The prevalence of AF is higher in HF (32.7%) compared to CM (19.2%) possible due to higher mean age in HF patients (71.8 years) compared to CM (42.7 years) because AF correlates with age. However, the prevalence of VT and PVC is much higher in CM patients (38.0% and 56.6%) compared to HF (3.7% and 13.3%). In both HF and CM, the ECG test is more useful on the differential diagnosis of arrhythmogenic right ventricular cardiomyopathy (ARVC), where it can differentiate ARVC from right ventricular outflow tract induced VT. In addition to diagnostic value, ECG-assessed arrhythmias can guide therapeutic intervention since AF and VT can be life-threatening and may require specific antiarrhythmic therapy.