A 77-year-old woman with a history of hypertension, hypothyroidism and leg edema presents with increasing fatigue and dyspnea. An echocardiogram done two years ago demonstrated a left ventricular ejection fraction (LVEF) of 60% with diastolic dysfunction. An electrocardiogram (ECG) is performed (Figure 1).
The ECG shows which of the following?
The correct answer is: D. Right ventricular (RV) strain.
The QRS axis is borderline leftward (approximately 5-10 degrees); therefore, left anterior fascicular block is incorrect. The asymmetric T wave inversion in V1-V3 are classic for RV strain and offer a valuable learning point as these are often mistaken as ischemic changes; therefore anterior ischemia is an incorrect choice.
A 2-D echocardiogram showed a moderate right atrial enlargement with severe pulmonary hypertension. The RV pressure was estimated at 92 mm Hg.
Although poor R wave progression with prominent S wave in V4-V5 suggests right ventricular hypertrophy (RVH), however, the other specific criteria of RVH (see below) are not present in this ECG. Therefore, the correct answer is RV strain.
RVH is seen in congenital heart disease (cyanotic and acyanotic) and acquired causes including athlete's heart, chronic obstructive pulmonary disease, acute pulmonary embolism, and pulmonary hypertension.1
This ECG criteria of RVH include precordial voltage criteria including R/S ratio of V1 >1 or R/S ratio of V5 or V6 <1 or R voltage of V1 >6 mm2 or R voltage of V1 + S voltage of V5 or V6) >10.5 mm (The Sokolow-Lyon criterion). An inverted T wave in V1-V3 is another criteria of the RV strain / RVH, which is the only criteria present in this case.1
Correlation of the ECG to echocardiographic criteria of RVH was conducted in 264 military subjects2 and showed the following:
No correlation between the voltage criteria and echocardiographic findings of the RVH
Low prevalence of ECG-RVH (00.76%)
Low sensitivity of each ECG criterion for RVH (016.7%)
High specificities (> 90%)
Low positive predictive values (0- 7.7%)
High negative predictive values (> 94%)
The ECG criteria are more sensitive in congenital heart diseases compared to acquired etiologies
Nikus K, Pérez-Riera AR, Konttila K, Barbosa-Barros R. Electrocardiographic recognition of right ventricular hypertrophy. J Electrocardiol 2018;51:46-9.
Meng FC, Lin YP, Su FY, Yu YS, Lin GM. Association between electrocardiographic and echocardiographic right ventricular hypertrophy in a military cohort in Taiwan: The CHIEF study: ECG criteria for RVH. Indian Heart J 2017;69:331-3.