CCI Vascular Hemodynamics Principles 5

Question 1

In lower extremity arterial occlusion, which collateral pathway most commonly reconstitutes the popliteal artery?

Accepted Answer

Geniculate anastomosis around the knee

Answer

The geniculate arteries form an anastomotic network around the knee that reconstitutes the popliteal artery distal to a femoral occlusion.

Question 2

The acceleration time (AT) measured in intrarenal arteries is prolonged when:

Accepted Answer

There is significant proximal renal artery stenosis

Answer

Significant renal artery stenosis dampens the waveform, prolonging the time from onset of systole to peak systolic velocity (AT > 70–80 ms).

Question 3

Which hemodynamic change occurs during exercise in a patient with hemodynamically significant PAD?

Accepted Answer

ABI decreases due to inability to raise distal pressure

Answer

During exercise, vasodilation increases flow demand but the stenosis limits pressure transmission, causing ankle pressure to fall and ABI to decrease.

Question 4

What does the term 'critical stenosis' refer to in vascular hemodynamics?

Accepted Answer

The degree of stenosis beyond which resting flow begins to fall

Answer

Critical stenosis is the threshold (approximately 75% area reduction or 50% diameter reduction) beyond which autoregulatory mechanisms can no longer maintain resting flow.

Question 5

In the venous system, the primary driving force for venous return from the lower extremities during ambulation is:

Accepted Answer

Calf muscle pump compressing deep veins

Answer

The calf muscle pump compresses deep veins during walking, propelling blood proximally and reducing venous pressure in the leg.

CCI - Cardiovascular Credentialing International Practice Test

CCI - Cardiovascular Credentialing International Practice Test

CCI Vascular Hemodynamics Principles 5