Examine this patient's pulses.



· Past history of insertion of an arterial line for blood gases or arterial pressure.

· Systemic symptoms in the past (Takayasu's arteritis).

· Past history of cardiac surgery (Blalock-Taussig shunt).

· Cervical rib.


· Left radial pulse is weaker than the right.

· Examine all other pulses (including carotid, brachial, femoral, popliteal, posterior tibial and dorsalis

pedis pulses).

· Check the blood pressure in both the upper limbs (differences in blood pressure between both arms

of more than 10 mmHg systolic or 5 mmHg diastolic are abnormal).


This patient has an absent radial pulse (lesion) which is due to a previous Blalock-Taussig shunt.


In which conditions may the pulse rate in one arm differ from that in the other?

Usually, slowing of the pulse on one side occurs distal to the aneurysmal sac. Thus, an aneurysm of the

transverse or descending aortic arch causes a retardation of the left radial pulse. Also, the artery feels

smaller and is more easily compressed than usual. An aneurysm of the ascending aorta or common

carotid artery may result in similar changes in the right radial pulse.

What are the causes of absent radial pulse?

· Aberrant radial artery or congenital anomaly (check the brachials and blood pressure).

· Artery tied off at surgery or previous surgical cut-down.

· Catheterization of the brachial artery with poor technique.

· Following a radial artery line for monitoring of blood gases or arterial pressure.

· Subclavian artery stenosis.

· Blalock-Taussig shunt on that side (shunt from subclavian to pulmonary artery).

· Embolism into the radial artery (usually due to atrial fibrillation).

· Takayasu's arteritis (rare).

What are the causes of differences in blood pressure between arms or between the arms and


· Occlusion or stenosis of the artery of ally cause.

· Coarctation of the aorta.

· Dissecting aortic aneurysm.

· Patent ductus arteriosus.

· Suprava!vu!ar aortic stenosis.

· Thoracic outlet syndrome.


What do you know about Takayasu's arteritis?

It tends to affect young women and most of' the cases have been h'om Japan. Prodromal systemic

symptoms include fever, night sweats, anorexia, weight loss, malaise, fatigue, arthralgia and pleuritic

pain. It predominantly involves the aorta and is of three types: Type I (Shimizu-Sano) which involves

primarily the aortic arch and brachiocephalic vessels; Type II (Kimoto) which affects the

thoraco-abdominal aorta and particularly the renal arteries; Type III (Inada) with features of Types I and

Types I and III may be complicated by aortic regurgitation.

{ M. Takayasu (1860-1938), Japanese ophthalmologist