Vascular Pathologies (Renal)

A set of Q&A flashcards focused on renal vascular pathologies, their mechanisms, imaging techniques, and clinical implications.

What is the primary role of the kidneys in vascular physiology?

Regulation of blood volume and blood pressure.

What happens when renal blood flow decreases?

The body activates mechanisms to increase blood pressure.

What is renal artery stenosis?

Narrowing of the renal artery.

What is renal hypertension?

High blood pressure caused by renal artery stenosis.

What type of hypertension results from renal stenosis?

Secondary hypertension.

Why is renal hypertension considered secondary?

It has a known underlying cause.

What are the two main causes of renal artery stenosis?

Fibromuscular dysplasia and Atherosclerosis.

What is fibromuscular dysplasia?

Abnormal growth in arterial walls causing narrowing.

What is atherosclerosis?

Plaque buildup narrowing arteries.

What is the initial effect of renal artery stenosis?

Decreased blood flow to the kidney.

How does the kidney interpret reduced blood flow?

As low systemic blood pressure.

What hormone is released in response to decreased blood flow?

Renin.

What does renin ultimately cause?

Increased blood pressure.

How does renin increase blood pressure?

By promoting salt and water retention.

What system is responsible for the response to decreased renal blood flow?

Renin-angiotensin-aldosterone system (RAAS).

What compensatory mechanism occurs initially in response to renal artery stenosis?

Collateral circulation develops.

Why is compensation ultimately insufficient in renal artery stenosis?

Blood supply remains inadequate long-term.

What is the main systemic effect of renal stenosis?

Hypertension.

What fluid-related symptom may occur due to renal stenosis?

Edema.

Where is edema commonly seen in patients with renal stenosis?

Lower extremities.

What happens to urine output in renal artery stenosis?

Decreases.

Why might patients with renal stenosis still feel urinary urgency?

Altered renal regulation despite low output.

Is plain radiography useful for renal stenosis?

No.

What ultrasound technique is used to assess renal stenosis?

Doppler ultrasound.

What does Doppler ultrasound measure?

Blood flow in renal arteries.

What is a limitation of ultrasound in diagnosing renal stenosis?

Operator dependent.

What do CT and MRI show in renal stenosis?

Narrowed artery and reduced perfusion.

What imaging feature is seen in fibromuscular dysplasia?

“String of beads.”

What causes the “string of beads” appearance in fibromuscular dysplasia?

Multiple areas of narrowing.

What is the gold standard for diagnosing renal stenosis?

Angiography.

What advantage does angiography provide in renal stenosis?

Diagnosis and treatment.

What is the first step in the treatment of renal hypertension?

Control blood pressure.

What do medications target in the treatment of renal hypertension?

Renin pathway.

What procedure restores blood flow in renal artery stenosis?

Angioplasty with stent insertion.

What is done in severe cases of renal artery stenosis?

Surgical bypass.

Why does renal stenosis cause systemic hypertension?

Kidney misinterprets low perfusion as low BP.

What is the key hormone driving hypertension in renal stenosis?

Renin.

What distinguishes fibromuscular dysplasia from atherosclerosis on imaging?

String of beads pattern.

What is the relationship between renal stenosis and RAAS?

Stenosis activates RAAS.

What is the key concept linking kidney blood flow and blood pressure?

Reduced renal perfusion → increased systemic BP.