Cardiology Flashcards
Autoregulation pathway of BP re: increased CO?
increased CO -> increased MAP - detected by aortic and carotid baroreceptors ->vasodilation -> reduced TPR = reduced CO
Pathway of pressure natriuresis (increased MAP)?
increased MAP -> increased renal perfusion = increased GFR = reduced aldosterone -> increase Na and H2O excretion (natriuresis)
Equation for BP
BP = CO x SVR
CO = HR X SV MAP = dBP + 1/3 pulse pressure
RAAS pathway
JG cells produce renin renin = angiotensinogen -> angiotensin I ACE = angiotensin I -> angiotensin II ang II = aldosterone production, systemic vasoconstriction, vasoconstriction of afferent and efferent arterioles aldosterone = Na reabsorption
Causes of primary HTN?
- lifestyle
- medication
- family history/ genetics
Causes of secondary HTN?
- endocrine (aldosterone, glucocorticoid, hyperthyroid, hyperparathyroid, chatecholamines)
- CKD (including PCKD)
- vascular (coarctation of aorta, renal artery stenosis)
- OSA
Rx than can induce HTN?
- NSAIDs
- corticosteroids
- exogenous androgens/ estrogens
- liquorice root (aldosterone-like), antidepressants
Will BP cuff that is too small over or under estimate BP?
- small = overestimate BP
Exam for end organ damage?
- fundoscopy (copper wiring, cotton wool spots, AV nicking, papilledema)
- signs LVH (loud S2, S4, sustained apex beat)
- signs CHF (elevated JVP, S3, lung crackles, ascites, leg edema)
- peripheral vascular exam (pulsatile abdo mass, no peripheral pulses)
Lab investigations with HTN?
- UA and Cr (CKD)
- electrolytes (hypoK with hyperaldosteronism)
- fasting glucose and lipid profile (CV risk)
- 12-lead ECG (LVH, prior MI)
Workup secondary causes HTN?
endocrine
- TSH, PTH, 24h urine metanephrines, aldosterone, renin, aldosterone/renin ratio, 24h urine free cortisol, dexamethasone suppression test
ckd
- serum Cr and estimated GFR
vascular
- trans thoracic echo, CT or MR angiography (coarctation)
- captopril renal scan, abdo US with doppler, MRI (renal artery stenosis)
osa
- sleep study
Dx HTN
- BP >140/90 on 3 occasions (or if end organ damage, kidney disease, DM)
- at least 1 home, ambulatory or 24h BP monitoring recommended
OR single measurement >180/90
office >140/90
ambulatory/home >135/85
24h average >130/80
Classify HTN
normal <120/80
preHTN 120-139/ 80-89
stage 1 HTN 140-159/ 90-99
stage 2 HTN >160//>100
Target organ damage from HTN
- cerebrovascular disease
- hypertensive retinopathy
- HF
- CAD
- CKD
- peripheral arterial disease
Tx HTN
Lifestyle
- Na <1.8g/d
- weight loss
- EtOH reduction
- exercise
- diet
target <140/90
DM target <130/80
first line rx
- thiazide diuretics
- ACEi/ARBs (non-black pt)
- long acting CCB
- b-blocker (<60yr)
AntiHTN for DM?
ACEI or ARB
AntiHTN for asthma?
CCB (nondihydropyridine)
AntiHTN for prior MI?
ACEI, b-blocker
AntiHTN for angina?
b-blocker, long acting CCB
AntiHTN for CKD?
ACEI, ARB (caution)
AntiHTN for CHF?
ACEI, b-blocker, aldosterone antagonist
AntiHTN for migraines?
b-blocker, long acting CCB
AntiHTN for raynaud, coronary spasm?
long acting CCB
Which anti-HTN causes dry cough? Why?
- ACEI -> bradykinin related