Left Ventricular Hypertrophy - ECG
Left ventricular hypertrophy (enlargement of its muscle) is a frequent finding in chronic cardiac patients. The ECG usually shows the deep negative QRS amplitudes in V1 and V2 and high positive QRS amplitudes in V5 and V6. The QRS complexes can be wide and the heart ECG axis is twisted significantly to the left (horizontally). The overload of the left ventricle may be associated, in addition to the above-mentioned changes, with the occurrence of ST segment depression and negative T waves in V5 and V6.
Note: We calculate the so-called Sokolow-Lyon's index, which is the sum of the largest amplitude of the QRS in leads V1 and V6 (or V5, if it is higher than the V6). If the value is greater than 35mm (7 large squares), the left ventricular hypertrophy is very likely.
Left ventricular hypertrophy is determined by addition of the QRS amplitudes in leads V1 + V5 (red arrows). In addition, there is present the horizontal (left) heart ECG axis, that is visible from the leads aVL and aVF (blue ellipse).
Conclusion: Clinically, this finding is typical for the patients with chronic hypertension and coronary artery disease, for the patients with the aortic valve stenosis, etc. This finding should lead to an echocardiography and administration of regular doses of ACE-inhibitors as they have protective effect from hypertrophy of the heart muscle.