Systemic Hypertension Flashcards
Describe the categories of HTN and their pressures?
Normal = <120 / <80 Pre = 120-139 / 80-89 Stage 1 = 140-159 / 90-99 Stage 2 = >160 / 100 Isolated Systolic = ≥140 / <90 (only the systolic number is high)
What is considered a hypertensive blood pressure?
2 readings of >140/90
Essential hypertension is also known as what?
Primary hypertension
Primary hypertension is caused by what?
Idiopathic but related to hereditary and metabolic causes
Secondary hypertension is caused by what? (6)
HTN is secondary to a known disease:
- Renal disease
- Endocrine/hormonal
- CNS: Increased sympathetic tone (fight/flight)
- Pituitary/Hypothalamic (Cushing Disease)
- Hyperthyroidism
- Aortic coarctation
What is mean pressure?
Average pressure over the cardiac cycle
What is the formula for MAP?
- (2 x DBP + SBP) ÷ 3
2. CO x SVR
How is pulse pressure calculated?
PP = SBP - DBP
Any factor which increases CO will increase what?
Average blood pressure
Any factor which increases systemic vascular resistance will increase what?
Mean arterial blood pressure
What is the main mechanism of HPnEF (HFpEF)?
Diastolic dysfunction
What is the number one symptom of diastolic dysfunction?
Dyspnea
Resistance increases with an increase of what factors?
Length of vessel, viscosity, and decreased radius
A compliant vessel has what kind of pulse pressure?
Lower pulse pressure
A stiffer vessel has what kind of pulse pressure?
Wider pulse pressure
What happens to right heart filling with inspiration?
Increased right heart filling
What happens to right heart filling with expiration?
Decreased right heart filling
What is volemia?
Total blood volume
What two factors increase volemia?
Water retention and total body mass
What mechanism causes CHF?
Increased work load (afterload) on an overloaded muscle and diastolic dysfunction
What mechanism causes CAD?
Endothelial damage in coronary artery accelerates plaque formation
What mechanism causes PVD?
Endothelial damage accelerates plaque formation
What mechanism causes renal failure?
Pressure too high for kidneys to function well which leads to endothelial damage
What mechanism causes angina?
Increased workload of the muscle and decreased coronary perfusion
What is EDRF?
Endothelium relaxation factor
Nitric oxide is a product of what?
Metabolism
What does nitric oxide do?
Makes the endothelium release EDRF which leads to vasodilation
What does EDRF allow the smooth muscle cells of the tunica intima and media to do?
Relax
What is endothelial function analysis based on?
Nitric oxide measurement
What needs to be modified first for hypertension management?
Lifestyle
Name three diuretics and their main effect:
- Dyazide
- Hydrochlorothiazide
- Metazone
Lowers volemia by promoting urination (excreting salt with water) which reduces afterload and preload
Name three beta blockers and their main effect:
- Acebutolol
- Metoprolol
- Propranolol
Blocks the sympathetic stimulation to reduce HR by 25% and allow better contraction and profusion (reduces BP)
Name three calcium channel blockers and their main effect:
- Dil-zem
- Ni-pine
- Vera-mil
Block calcium from entering the muscle cells which reduces contraction/inotropy lowering afterload
Name three ACE inhibitors and their main effect:
- Captopril
- Lisinopril
- Ramapril
Prevent angiotensin from causing arterial constricting which lowers afterload
EF measures what type of function?
Systolic
E/A ratio measures what type of function?
Diastolic
E/e prime ratio measures what type of function?
Diastolic
Pulmonary v profile measures what type of function?
Diastolic
Tissue doppler measures what type of function?
Diastolic
Explain concentric remodeling:
Normal LV mass with increased relative wall thickness
Explain concentric hypertrophy:
Increased LV mass and increased relative wall thickness
Explain eccentric hypertrophy:
Increased LV mass with normal or decreased relative wall thickness (Why? Starting to ‘bag out’)
LV mass linear technique can be done with what?
M-mode or 2D
LV Mass index formula?
Total LV mass/BSA
What is RWT and state the formula for?
Relative Wall Thickness relates wall thickness to chamber size in diastole
2PWTd/LVIDd
What is a normal relative wall thickness?
<0.42
What are risk factors for HTN? (12)
- Age
- African
- Male
- Smoking
- Obesity
- Inactivity
- Diabetes
- Stress
- Dyslipidemia
- Sodium
- Alcohol
- Inadequate calcium or potassium
How do higher heart rates affect mean pressure?
Higher heart rates equal higher pressure because there is more time spent in systole
What happens to the pulse pressure during AR?
The PP gets larger because the systolic component goes up (contracting harder - starlings law) and the diastolic component goes down (inability to fill) creating a bigger diff between SBP and DBP
PP = SBP - DBP
What does SVR sand for?
Systemic Vascular Resistance
Describe BP regulation?
The peripheral resistance, SV(inotropy) and HR determine CO which is regulated by the baroreceptors in the carotid bulb/aorta that either tell the heart to pump more to profuse the brain or less. (As we age baroreceptors need help from medication to regulate)
How does volemia affect BP?
Increased blood volume increases blood pressure
Explain the relationship of salt and BP?
Increased sodium chloride (Na+Cl-) = increased water retention (to dilute) = increased volemia = increased BP
What diseases are caused by HTN?
- CHF
- CAD
- PVD (peripheral vascular disease)
- Renal failure
- Angina
What 3 things need to be regulated to manage HTN?
- Blood Volume regulation
- CO regulation (SV and HR)
- Peripheral Resistance regulation
Describe the effect of exercise on HTN management?
- Muscle contraction
- Vasodilation of vessels supplying the muscles
- Increased O2 supply and CO2 removal
- Lower SVR
- Lowers BP
Describe the effect of smoking on HTN and how quitting helps? (2)
- Smoking decreases O2 to the brain and releases catecholamine which increases HR and BP
- 50% reduction for MI and CVA in the 1st year after quitting, another 50% after 5 years
How does ASE recommend indexing LV mass with obese patients and why?
Indexing with height only instead of BSA
because their huge BSA will make an enlarged LV mass appear normal when indexed