Final answer:
Systemic hypertension is most typically associated with electrocardiographic evidence of left ventricular hypertrophy, where enlargement of the left ventricle occurs to compensate for increased workload from higher blood pressure.
Step-by-step explanation:
Electrocardiographic evidence associated with systemic hypertension typically includes signs of left ventricular hypertrophy (LVH). LVH occurs due to the increased workload on the heart caused by higher blood pressure, leading to a compensatory increase in the muscle mass of the left ventricle to handle the elevated pressure it must pump against. On an electrocardiogram (ECG), LVH can manifest as enlarged R waves in leads I, aVL, V5, and V6, and deep S waves in leads V1 and V2, among other criteria (such as the Sokolow-Lyon index). It is important to note that while left atrial enlargement can also be seen in systemic hypertension, it is typically a secondary effect of the pressure overload caused by LVH, and the changes are different from those directly associated with LVH on an ECG.
By contrast, right atrial enlargement and right ventricular hypertrophy are commonly associated with conditions that affect the right side of the heart or lungs, such as pulmonary hypertension or chronic lung disease, and not primarily with systemic hypertension.