Heart Failure Flashcards
what is the main physiologic cause of HF
↓ LV contractility
MCC of HF
chronic hypertension
*ischemic cardiomyopathy is a second cause (MI, etc.)
short term response to compensate for ↓ CO due to heart failure (LV dysfunction)
Sympathetic discharge⇒ carotid sinus senses the decrease and fires
long term compensation for HF
RAAS system⇒ increases Na and H20 reabsorption by the kidneys to increase volume and retain CO
what two ways is RAAS activated
- Sympathetic discharge (carotid sinus)⇒ activation of β1 receptors in kidney = ↑ renin release
- JG apparatus in kidney ⇒ senses ↓ BP = ↑ renin release
How does renin help maintain BV and thus CO
Renin cleaves Angiotensin to Ang I; ACE cleaves Ang I to Ang II⇒ Ang II both vasoconstricts and stimulates aldosterone release from adrenal gland
where in adrenal is aldosterone released
zona glomerulosa in adrenal cortex
most potent vasoconstrictor in body
Angiotensin II
how does ↑ BV help maintain CO
increases preload, which increased SV
what are two negative effects that result due to increased BV along with decreased LV function
- pulmonary edema
2. peripheral edema
MCC of right sided HF
left-heart failure
signs of right-sided heart failure (3)
- peripheral edema (pedal, sacral edema)
- jugular venous distension (JVD)
- hepatosplenomegaly ⇒ due to IVC backup, causes chronic venous congestion in liver
pathology seen in right heart failure
“Nutmeg liver”⇒ due to chronic passive congestion
signs of left sided heart failure (4)
- Dyspnea on exertion
- Rales
- Paroxysmal nocturnal dyspnea
- orthopnea (increase in venous return/ preload when supine exacerbates pulmonary edema)
- these are all due to Pulmonary edema⇒ lung involvement= think LEFT HEART; if right heart fails, you wont even get fluid to the lungs!!
characteristic pathology seen in left heart failure
“heart-failure cells”⇒ hemosiderin-laden macrophages in lung
