Author + information
- Hou Juanni,
- Dachun Yang,
- De Li and
- Haifeng Pei
As an inherited disease and a crucial health problem, arrhythmogenic right ventricular cardiomyopathy (ARVC) is characterized by fibrofatty infiltration of the right ventricular myocardium. With sudden death often being the first presentation of ARVC, early diagnosis is essential. Up to date, the electrical manifestations of right ventricle are important to aid in the differential diagnosis of ARVC, without invasive harms. This paper reveals some new electrocardiogram (ECG) features in ARVC patient, especially epsilon waves.
A 66-year-old farmer presented to the Emergency Department with continuous palpitation, chest tightness, and profuse sweating with no obvious predisposing causes. An ECG indicated ventricular tachycardia (VT). The patient experienced a sudden drop in blood pressure and acute confusion. After an immediate electrical conversion, his consciousness was gradually restored, and symptoms relieved. The patient was then transferred to the Department of Cardiology to receive ECG, echocardiography, coronary angiogram, biochemical assays, endocardiac tracing and radiofrequency ablation.
In VT ECGs: When the rate of VT is higher than 150 beats/min, there were no epsilon waves in the precordial leads; instead, when the rate of VT is slower than 120 beats/min, epsilon waves appeared ahead of QRS waves in leads V1-V2. At the same time, endocardiac tracing revealed that the corresponding local potential originating from RVOT occurred prior to the ventricular one. In sinus ECGs: T wave inversions were found in leads III, avF, and V1-V3, while epsilon waves were found behind QRS waves in leads V1-V3 and avR. Both atrial and ventricular premature beats were found to originate from the right ventricular apex, with epsilon waves appearing behind QRS waves. Biochemical assay data: Cardiac troponin I level was 0.714 μg/L (normal:0-0.06 μg/L), serum B-type natriuretic peptide level was 466.530 pg/mL (normal:0-100 pg/mL), serum D-dimer level was 8.14 mg/L (normal:0-0.55 mg/L), serum creatinine level was 144.00 μmol/L (normal:44-133 μmol/L). Echocardiography data: The tests revealed remarkably enlarged right atrium and right ventricle, and widened ROVT. Uncoordinated motions of the left and right ventricular walls were also detected. The left ventricular diastolic function was reduced to 55%. Moreover, coronary angiogram revealed no vascular stenosis. Based on Task Force Criteria 2010, this patient met at least 2 major criteria for the diagnosis of ARVC, the bilateral ventricular dilation and the existence of epsilon waves in leads V1-V3. In the end, appropriate therapies were provided for this patient including pharmacological intervention and radiofrequency ablation.
ARVC can develop into bilateral ventricles disease, with VTs showing irregularly irregular rhythm. The position relationship between epsilon wave and QRS complex in VT depends on ventricular activation sequence, that is, the localization of epsilon wave depends on where VT is originating from.