The Cardiogram of Congenital and Acquired Right Ventricular Hypertrophy

In recent years the accuracy of cardiographic diagnosis of ventricular hypertrophy has greatly improved, largely as a result of the introduction of multiple chest leads and unipolar leads. The diagnosis of left ventricular hypertrophy has presented considerably less difficulty than that of right hypertrophy probably because the left ventricle is normally dominant over the right. But even with the use of multiple unipolar and bipolar leads, right ventricular hypertrophy of appreciable degree not infrequently fails to give any cardiographic evidence of its presence. The criteria for right ventricular (R.V.) hypertrophy proposed by They consist of a dominant R wave in right prxecordial leads (VI), with a delayed intrinsicoid deflection and often with T wave inversion. The R wave may be preceded by a small q wave Complete or partial bundle-branch block patterns may also occur. So-called extreme clockwise rotation indicated by a dominant S wave in V5, and in many cases a dominant R in VR, completes the picture of severe R.V. hypertrophy. In less severe cases many, or all of these signs are absent, but the use of lead V4R has resulted in the detection of cases that would otherwise have been missed (Myers et al., 1948; and Roseoman, 1950) We have studied the value of lead V4R in R.V. hyper- trophy in 252 adult subjects (Camerini et al., 1956), and found that an Rs pattern in V4R was the sole evidence of R.V. hypertrophy in an appreciable number of cases, and we considered V4R to be a valuable addition to the cardiographic detection of R.V. hypertrophy.