What finding is most likely present in a patient experiencing subclavian steal syndrome during physical examination?

In subclavian steal syndrome, the primary physiological issue occurs when there is significant stenosis or occlusion of the subclavian artery proximal to the vertebral artery. This leads to a diversion of blood flow from the vertebral artery, which is responsible for supplying blood to the posterior circulation of the brain, to the subclavian artery during upper extremity use.

During physical examination, one may detect a supraclavicular bruit. This bruit indicates turbulent blood flow through the affected subclavian artery due to the narrowing or obstruction caused by the pathological condition. It is often best heard in the supraclavicular region where the subclavian artery can be evaluated directly. The presence of this bruit serves as a clinical sign that reflects the underlying vascular abnormality, supporting the diagnosis of subclavian steal syndrome.

The other options do not directly correlate with the vascular changes associated with this syndrome. A diastolic murmur at the cardiac apex is more typical in conditions related to heart valve issues, while increased jugular venous pressure often relates to heart failure or volume overload. A pansystolic murmur is associated with conditions such as mitral or tricuspid regurgitation and does not pertain to subclavian artery pathology