Resistant Hypertension
Definition BP of at least 140/90 (or 130/80 w/ diabetes or renal disease) that persists despite adherence of
treatment w/ adequate doses of at least 3 different class anti-HTN medications (including diuretic)
Possible etiologies - Renovascular HTN: renal artery stenosis**
- Renal HTN: chronic renal parenchymal disease (due to DM or HTN mostly)
- Other: Primary aldosteronism, pheochromocytoma, sleep apnea, "White-coat" phenomenon
Pathophysiology Renovascular HTN
↓ kidney perfusion → ↑RAAS → ↑vasoconstriction, ↑Na & volume retention → HTN
● Only one kidney needs to be affected
● Kidney perfusion depends on RAAS: after administration of RAAS inhibitor (ACEi or ARB) → ↓↓↓
kidney perfusion → kidney responds producing MUCH more renin → worsening symptoms
● Other anti-HTN only slightly ↓ BP, and then it rises again.
↑ risk of Risk related to degree of BP elevation
- Target-organ damage → renal failure
- Cardiovascular events → stroke, MI, heart failure
- Hypertensive crisis: BP > 180/120 + evidence of target-organ failure
- Urgency → w/o evidence of end-organ failure
- Emergency → w/ evidence of end-organ failure
Renal Artery Stenosis
Atherosclerosis - 90% Fibromuscular Dysplasia
Age at presentation > 50 yr (older patients) <40 yr (younger patients)
Sex Both Female
Lesion location Proximal, close to the aorta Middle or distal
Pathophysiology - In systemically atherosclerotic patients - Abnormal development of collagen and muscle
- LDL, calcium and immune cell deposition → tissue in renal artery
narrowing of the renal artery ● Areas of stenosis → thick fibers
● Closer to the aorta due to angle → ● Areas of aneurysm → think fibers
turbulent flow → "String of beads"
- Can present aortic and arterial dissection
Imaging
Treatment Angioplasty w/ stent, statins, anti-HTN therapy Angioplasty
Prognosis Bad prognosis. Hypertension doesn't completely Good prognosis & normotensive after
normalize & still at risk due to systemic revascularization
atherosclerosis.
Definition BP of at least 140/90 (or 130/80 w/ diabetes or renal disease) that persists despite adherence of
treatment w/ adequate doses of at least 3 different class anti-HTN medications (including diuretic)
Possible etiologies - Renovascular HTN: renal artery stenosis**
- Renal HTN: chronic renal parenchymal disease (due to DM or HTN mostly)
- Other: Primary aldosteronism, pheochromocytoma, sleep apnea, "White-coat" phenomenon
Pathophysiology Renovascular HTN
↓ kidney perfusion → ↑RAAS → ↑vasoconstriction, ↑Na & volume retention → HTN
● Only one kidney needs to be affected
● Kidney perfusion depends on RAAS: after administration of RAAS inhibitor (ACEi or ARB) → ↓↓↓
kidney perfusion → kidney responds producing MUCH more renin → worsening symptoms
● Other anti-HTN only slightly ↓ BP, and then it rises again.
↑ risk of Risk related to degree of BP elevation
- Target-organ damage → renal failure
- Cardiovascular events → stroke, MI, heart failure
- Hypertensive crisis: BP > 180/120 + evidence of target-organ failure
- Urgency → w/o evidence of end-organ failure
- Emergency → w/ evidence of end-organ failure
Renal Artery Stenosis
Atherosclerosis - 90% Fibromuscular Dysplasia
Age at presentation > 50 yr (older patients) <40 yr (younger patients)
Sex Both Female
Lesion location Proximal, close to the aorta Middle or distal
Pathophysiology - In systemically atherosclerotic patients - Abnormal development of collagen and muscle
- LDL, calcium and immune cell deposition → tissue in renal artery
narrowing of the renal artery ● Areas of stenosis → thick fibers
● Closer to the aorta due to angle → ● Areas of aneurysm → think fibers
turbulent flow → "String of beads"
- Can present aortic and arterial dissection
Imaging
Treatment Angioplasty w/ stent, statins, anti-HTN therapy Angioplasty
Prognosis Bad prognosis. Hypertension doesn't completely Good prognosis & normotensive after
normalize & still at risk due to systemic revascularization
atherosclerosis.
