This EKG gives the diagnosis…and more!

Rate and rhythm: sinus at 110/minute
Axis: right axis deviation at +120°
Intervals: PR, QRS, and QTc are normal
Chamber enlargement: the tall R wave in V1 and a right axis à right ventricular hypertrophy
ST-segment and T-wave changes: T wave inversion in V1-3 is consistent with right ventricular strain pattern

This EKG is a good example of how the differential of a tall R wave in lead V1 can be helpful (see “Tall R waves in V1” under website section EKG discussion).

Four causes of a tall R wave in V1 with their hints:
RBBB                            QRS ≥ 0.11
WPW type A               delta wave and short PR interval
Old posterior MI      accompanies an old inferior MI
RVH                               right axis deviation

This EKG is from a patient with primary pulmonary hypertension and significant RVH.

Notice the respiratory rate…since the V1 lead is on the chest, the rhythm strip records the chest excursion. The respiratory rate is approximately 24/minute!