Ans is 'd' i.e., Coarctation of aoa Clinical manifestations of COA Symptoms of coarctation of aoa occurs due to decrease in blood supply distal to aoic obstruction. o If obstruction is distal to left subclan aery, manifestations are due to aerial insufficiency to lower limbs. Intermittent claudication Pain Weakness of Leg Dysnea on running Weak pulses and lower BP in the lower extremities -4 Delayed or weak impalpable femora's compared to strong brachial aeries. Collateral circulation develops between precoarctation aerial branches and the post coarctation aeries through enlarged intercostal and internal mammary aeries. o This produces radiologically visible erosions (notching) of undersurface (inferior) of ribs. o Hypeension --> Headache, dizziness. o If the obstruction is proximal to left subclan aery --> Blood supply to left arm (supplied by left subclan) is interrupted whereas blood supply to right arm is normal ---> Pressure difference in two arms. Murmur in coarctation of aoa o The blood passing through the narrowed aoa ----> Midsystolic murmur in anterior pa of chest, back and spinous process. o When lumen becomes severly narrowed the blood flow through it, turns into a high velocity jet ---> Continous murmur. o COA is associated with bicuspid aoic valve in 50-80% of patients. The bicuspid valve produce aoic regurgitation --> Diastolic murmur.