Hypertension and atherosclerosis Flashcards
Why does cardiac hypertrophy occur?
In response to pressure overload
What happens in response to cardiac hypertrophy, 4 steps
Myocardial dysfunction due to insufficient coronary blood supply
Leads to cardiac dilation
This causes congestive heart failure and sudden death
Microscopically, what will you see when there is hypertrophy?
Pinker fibers due to more mitochondria, boxcar nuclei, fibrosis
In systemic HTN how does the heart change and what affect does this have?
Increase in wall thickness and stiffness of the left ventricle. This leads to impaired diastolic filling and possible atrial enlargement
What is seen in early LV hypertrophy and later?
Early on you see an increase in myocyte diameter
Later on there is nuclear enlargement and fibrosis
What are the two possible causes of pulmonary hypertension?
Cor pulmonale and left side hypertension
Resistance in the lungs causes?
Right side hypertrophy
What causes acute cor pulmonale? What does this lead to?
Following massive pulmonary embolism which leads to right side dilation
What does chronic cor pulmonale cause?
Right ventricular hypertrophy and dilation
What is arteriopathy?
When a normal sized artery gains a lot of smooth muscle and angioma like vessels around it
Hyaline arteriosclerosis and hyperplastic arteriosclerosis affect vessels of what size?
Smalle
Describe the pathogenesis of hyaline arteriosclerosis
- Chronic hemodynamic stress leads to
- Plasma proteins leaking from cells
- Synthesis of smooth muscle matrix causing hyalinized, narrow vessels
What are the risks factors for hyaline arteriosclerosis?
Elderly, hypertension, diabetes, nephrosclerosis from hypertension in the kidney
Does hyaline arteriosclerosis naturally occur in elderly people?
Yes
What causes hyper plastic arteriosclerosis?
Very high blood pressure, >200 mm Hg
What will be seen microscopically in hyper plastic arteriosclerosis?
Onion-skin lesions
What vessels are affected by atherosclerosis?
Medium and large vessels
What is the hallmark of atherosclerosis?
Atherosclerotic plaques
What is a risk factor for atherosclerosis that is related to periodontal disease?
C-reactive protein, released in response to the bacteria and also causes atherosclerosis
Describe how plaques form
High cholesterol and endothelial cell injury cause local increase in free radicals that oxidize lipid
Lipid is taken in by macrophages that become foam cells
The injured epithelium expresses adhesion molecules that cause T cells to interact with macrophages. They release cytokines that cause smooth muscle and endothelial stimulation
Which arteries are targeted by atherosclerotic disease?
The aorta, carotid, iliac, coronary, and popliteal arteries
What is atherosclerotic stenosis?
When atherosclerosis occludes the vessel beyond 70%, the critical stenosis point, and ischemic injury occurs
What else can affect plaques?
Epinephrine, waking and rising, vasoconstriction due to adrenergic agonists, emotional stress
