When combining the depth of the S wave in V1 and the height of the R wave in V5, what total indicates left ventricular hypertrophy?

When combining the depth of the S wave in V1 and the height of the R wave in V5, what total indicates left ventricular hypertrophy?

• A. 25 mm
• B. 30 mm
• C. 35 mm
• D. 40 mm

Answer: (C)

In assessing left ventricular hypertrophy (LVH) using an electrocardiogram (EKG), one of the common methods involves measuring the amplitude of specific waves in the appropriate leads. In this scenario, the depth of the S wave in lead V1 and the height of the R wave in lead V5 are combined.

A total of 35 mm indicates LVH because it reflects significant changes in the heart's electrical activity associated with the structural enlargement of the left ventricle. Typically, the criteria suggest that a sum greater than or equal to 35 mm is a clinically significant mark for diagnosing LVH. The height of the R wave in V5 and the depth of the S wave in V1 are particularly important because they provide insight into the electrical forces generated by the hypertrophied heart muscle.

The threshold values you see in this context are based on empirical data, meaning the specific measurement of 35 mm has been established through research and clinical findings as a reliable indicator for LVH, making it a critical criterion in EKG interpretations.