Arterial insufficiency is suggested by the skin changes described above and reduced or absent pulses. Patients may have claudication or it may be asymptomatic. Peripheral artery disease is an important marker of increased risk of cardiac disease and stroke.
In severe arterial insufficiency, elevation of the feet will lead to pallor with a ruddy rubor on lowering the feet (Buerger’s test). A delay in the onset of rubor in one leg may indicate more severe arterial insufficiency.
The ankle-brachial index is a useful measure of peripheral artery disease. A sphygmomanometer cuff is used to measure the systolic pressure from both brachial arteries and the two pedal pulses of each leg, using a hand-held Doppler device to identify systolic pressure. The highest pressure in any one limb, divided by the higher of the brachial pressures defines the ankle brachial index for that limb. An index of <0.9 indicates peripheral artery disease.
Acute arterial insufficiency may be associated with embolus (e.g. due to thrombus related to atrial fibrillation, anterior myocardial infarction, or infective endocarditis), or artery-to-artery embolisation. It is associated with an acutely painful white leg and is a medical and surgical emergency warranting early diagnosis and embolectomy. The fours “P’s” pain, pallor, pulseless and parasthesia are useful to remember.