Hypertension Flashcards
What is the definition of essential hypertension
-Systolic Blood pressure (BP) 140 mm Hg or higher
OR
-Diastolic BP 90 mm Hg or greater
-Elevated BP are consistent over time in patient’s usual state of health
-No evident secondary cause.
*Thus, Essential hypertension = Primary hypertension
Why do we call primary hypertension “essential hypertension”
- Systolic blood pressure (SBP) rises with age due to arterial stiffening (True)
- Historical Misconception : aged blood vessels “require” higher blood pressures for organ perfusion
What is the relationship between BP and mortality
“J-point” or “U-shaped” curve of mortality and BP
*high mortality w/ high pressures and very low pressures
Mortality greater for SBP over 139 vs. 100-119 mm Hg
Describe the pathophysiology of essential BP
- ↑ Cardiac Output (CO) and/or ↑ Peripheral Vascular Resistance (PVR)
- CO = Stroke Volume (SV) x Heart Rate (HR)
- PVR determined by systemic and local factors that either dilate or constrict arteries.
- Increased SV due to increased extra-cellular volume, generally from higher sodium levels
What can cause increased PVR?
- ↑ by SNS vasoconstriction
- ↑ by higher Angiotensin II (from ↑RAAS) and/or lower kallikrein-kinin levels
- Impaired endothelial-dependent local vasodilation (impaired local NO production or impaired NO-dependent signaling)
- Mediating factors: Metabolic stress of overweight/obesity – ↑insulin resistance
How do you make sure it’s hypertension
- recheck BP after patient seated calmly for 10 minutes (resting)
- Elevated BP over 2-3 visits over ≥ 2 weeks
- Make sure it’s “primary HTN” - rule out secondary causes,)
Risk stratification for HTN
- other CV risks: hyperlipidemia, smoking, DM2, known vascular dz
- assess for BP related end organ damage
What is the goal sodium intake daily
less than 1500-2000mg daily
What PE is important to do for HTN
- funduscopic
- cardiopulmonary
- pulses of 4 extremities
- neurologic examination
What is the appropriate measurement technique to take BP
- Patient seated 10 or more minutes
- Back supported and feet are on floor
- Arm supported at 90-degree angle
- Appropriate size cuff (use markings on cuff)
- Measure BP in both arms - highest BP guides treatment
- Record BP to closest even number
How do confirm the dx of HTN
2+ readings 140/90 or higher, spaced at least 2 weeks apart
- In anxious patients, consider home BP cuff or ambulatory BP monitor to rule out White Coat HTN (~13%)
- Rule out secondary causes of HTN
Secondary causes of HTN
- Heavy EtOH use (even mild withdrawal causes SNS activation)
- Most antidepressants are BP-neutral but venlafaxine will ↑BP
- Hypo and hyperthyroidism
- renovascular disease
- Primary renal disease
- OCPs
- NSAIDS
- Stimulants (cocaine, meth)
- PCC
- primary aldosteronism
- Cushing’s
- Sleep apnea**
- Coarctation of the aorta
When people are on 3 meds for HTN and its still not well controlled, you should think ____
secondary HTN
Clues to secondary HTN
- thin, health before age 30
- Obese with snoring and daytime somnolence? (OSA)
- Onset of HTN before puberty?– congenital
- Recently started on NSAIDs OR birth control containing estrogen OR venlafaxine OR taking steroids;
- Social hx for heavy EtOH use/SNS activating substances?
- Fatigue, unintentional weight gain, cold intolerance, constipation?
- Fhx of secondary cause
What are the 5 P’s of pheochromocytoma?
- palpitations
- perspiration
- pallor
- pounding HA
- increased BP
Screening for sleep apnea
- feel refreshed in the morning?
- Fall asleep easily
- snore?
- wake themselves up sometimes
What are Cushing features
- cushingoid facies,
- buffalo hump,
- increased supraclavicular fat pad,
- central obesity,
- purple stria
Assessing for target organ damage
- Neurological: HA, transient sx (blindness, weakness)
* R/O prior CVA w/ CN, strength, sensation, and cerebellar testing - CV: CP, DOE, claudication, decreased pulses, S4- LVH
- Opthalmology” cotton-wool spots, AV nicking
- Pulm: rales (CHF)
What are cotton wool spots
infarction of nerve fiber layer of the retina
Labs to rule out secondary causes of HTN
- Electrolytes (including sodium, potassium, calcium)
- Excludes hyperaldosteronism, hyperparathyroidism as secondary causes - Creatinine (rule out renal disease)
- Thyroid Stimulating Hormone (rule out hypothyroid)
Labs/tests to risk-stratify for HTN
- Lipid Panel (to further define 10yr CV risk profile)
- fasting glucose of HbgA1c (look for DM)
- EKG (assess for left ventricular hypertrophy as sign of cardiac damage from long-standing hypertension)
Counseling for life style modifications for HTN BEFORE starting meds
- Weight maintenance/loss: ↓10kg = ↓BP 5-20 mm Hg (only if BMI over/= 25)
- 30 minutes exercise/day: ↓BP 4-9 mm Hg
- Sodium <2400 mg/day: ↓BP 2-8 mm Hg (some are salt sensitive, ie. AA)
- Restrict EtOH: ↓BP 2-4 mm Hg (2 drinks/day for males, 1 drink/day for females)
Counseling after initiating medication for BP
- same as before starting meds
2. medication adherence
Eighth Joint National Committee on Hypertension (JNC8) Recommendations Goal BP:
- Adults 60 years or older and NO CKD: less than 150/90
- Adults 60 years or older and + CKD: less than 140/90
- Adults less than 60 years: less than 140/90
Compelling indications for classes of antihypertensive medications
- CKD: ACEI or ARB–> especially with proteinuria
- black/AA: diuretic or CCB
- all other race/ethnicity: diuretic or ACEI/ARBs or CCB
1st line agents for HTN
- Thiazide-type diuretic
- ACEI/ARB
Calcium-channel Blocker (CCB)
2nd line agents for HTN
- BB
- aldosterone antagonist diuretic (spironoloatone)
- others
Mechanism of action- decrease total body salt and water (decreased blood volume)
thiazide and loop diuretics
side effects of thiazide and loop diuretics
- Dehydration (MUCH more common with loop diuretics (e.g., furosemide) at higher doses, elderly can be sensitive to thiazides as well)
- Hypokalemia (monitor for this)
- Worsens insulin resistance in DM/metabolic syndrome
- Contra-indicated in pregnancy as increased extracellular volume needed to support fetus
- Increases uric acid and may cause gout attacks
Mechanism of Action
Competes with Aldosterone at distal renal tubule, conserves potassium while causing excretion of sodium/water
aldosterone antagonist
side effects of aldosterone antagonists
- Hyperkalemia (monitor electrolytes after initiation, contra-indicated if baseline non-hemolyzed potassium over 5.0-5.3 mg/dl)
- Dehydration (less profound than loop diuretics)
Beneficial effects of aldosterone antagonists
Uric Acid neutral, unique amongst diuretic class
Mechanism of Action
Inhibits activation of Renin-Angiotensin-Aldosterone system, leads to decreased salt/water retention by kidney and decreased peripheral vascular resistance
ACEI
Side effects of ACEI
- Hyperkalemia (monitor electrolytes after initiation, contra-indicated if baseline non-hemolyzed potassium over5.0-5.3 mg/dl)
- Cough (up to 10% of patients)
- Urticaria/Angioedema (1/3000)
- Contra-indicated in pregnancy (birth defects)
benefits of ACEI
Beneficial Effect: Up to 25% decreased incidence of DM in HTNive individuals
Mechanism of Action: Inhibits RAAS one step later than ACE-I (inhibits Angiotensin II binding to receptor and secretion of Aldosterone)
RAAS
Side effects of ARBs
- Hyperkalemia (same risks as ACE-I)
2. Angioedema- case reports of this in pts who had angioedema with ACE-I, but much rarer to occur than with ACE-I
benefits of ARBs
Decreased Insulin resistance (LIFE/ICARUS study), similar 25% decrease in DM in at-risk subjects to ACE-Is
MOA for dihydropyridine and non-DHP (CCBs)
Dihydropyridine (DHP): Vasodilate peripheral blood vessels and decrease vascular resistance
Non-DHP: Predominantly lower heart rate, have lesser peripheral dilation properties
Side effects of CCBs
- edema
- bradycardia (non-DHP)
- CHF exacerbation (non-DHP)
Mechanism of Action
Lowers heart rate (remember CO = HR x SV)
Decreases peripheral vascular resistance mediated by SNS
BB
Side effects of BB
- CONTRA-INDICATED in asthma ( bronchoconstriction)
- Bradycardia (proportional to dose)
- CHF exacerbation (use encouraged in STABLE CHF patients, but with caution advised for low dose initiation and slow up-titration)
- Masks signs/symptoms of hypoglycemia in diabetes
- Increased insulin resistance in 1st-generation, neutral in 2nd-gen (metoprolol), decreased insulin resistance in 3rd-gen (carvedilol) per GEMINI study)\
What BP meds are used in pregnancy
1st-line: Methyldopa (long track record)
2nd-line: Labetalol
Additional options:
- Extended release nifedipine (safety well-documented in 3rd trimester)
- Hydralazine (Rare fetal thrombocytopenia reported with hydralazine)
When would you likely start 2 BP meds in combo
if SBP is over 160mmHg
*hard to differentiate if pt has side effect
Flow chart of HTN management
- Determine BP goal for age/CKD status
- Tx w/ lifestyle interventions
- if BP still above goal, start BP rxn
- If BP remains above goal despite lifestyle interventions and starting BP rx: Reinforce lifestyle and adherence, Up-titrate or add rx
- Reassess/repeat
*can take about 2 weeks to see a difference in BP after med change
CKD is defined as
GFR less than 60 ml/min/1.73 m2 OR
Microalbuminuria (over 30 mg albumin/g of creatinine)
If there are no compelling indications, what anti-hypertensive medication should be first-line?
JNC-8 states thiazide diuretic or ACE-inhibitor or ARB or CCB
___ superior in reducing CV events/death by 2.2%
ACE-I + CCB
__ class of HTN is superior to ___ for stroke;
and
___ superior to __ for CHF
Diuretic
ACE-I
Diuretic
CCB
CCB-ACE-I combinations may be slightly more beneficial than diuretics/ACE-I combinations in certain populations including
older white pts at high risk for CAD w/ normal creatinine clearance
Studies have shown __ conditions may show benefit from looser control, but some show __ conditions are better with tighter control
looser: DM (150/90
Tighter: better stroke outcomes and equivalent mortality
What is a hypertensive urgency
Blood pressure 180/120 or higher WITHOUT end-organ damage
*Often requires emergent evaluation for studies to rule out end-organ damage
Tx of hypertensive urgency
- oral medications to lower BP to less than 160/100 over 3-6 hours
- Recommendation for initiating 1 medication with close follow-up to add a second – choose appropriate class of medication for patient in long-term with preference for diuretic class
What is hypertensive emergency
Elevated BP (180/120 mm Hg or over) AND end-organ damage **End-organ damage
Neuro signs of end organ damage from HTN
- reversible encephalopathy,
- hemorrhagic stroke,
- retinal exudates/hemorrhages- Retinal exudates due to ischemic changes, hemorrhages due to leaks of affected vessels.
- papilledema
CV signs of end organ damage from HTN
- Unstable angina/MI,
- heart failure with pulmonary edema,
- aortic dissection
renal damage signs of end organ damage from HTN
- proteinuria,
- hematuria,
- acute renal failure
Evaluation of Hypertensive emergency (malignancy)
- Question for sx of emergency
- Exam including funduscopy, neurologic exam, and full cardiopulmonary exam including pulses and jugular venous pressure (JVP) assessment
- Data: UA, renal fxn, creatinine, EKG, neuro imaging ONLY required if +sx or abnormal exam
*Triage patient to Emergency Department if +sx or exam findings concerning for end-organ damage
Therapy for hypertensive emergency
- Performed in E.D./ICU
- IV medications used to lower DBP by MAX of 25% in 2-6 hours
* Can get hypoperfusion of the brain if you lower it too quickly - Goal DBP 100-105 mm Hg within minutes to 2 hours
What meds are commonly used to lower BP In a hypertensive emergency
- Nitroprusside (arterial/venodilator, limited by thiocyanate toxicity, especially in those with impaired renal function)
- Labetalol (alpha and beta-blocker)
- Fenoldopam (peripheral dopamine-1 agonist causes vasodilation, improves renal perfusion)
- Hydralazine (peripheral vasodilator)
*Used IV