Cardiology-Congestive Heart Failure

Question 0

Clinical consequences Left-sided heart failure

Answer 0

Pulmonary Congestion!!!
(when heart cannot pump blood forward, blood begins to pile up backward within blood vessels of lung)

Pulmonary congestion –> Pulmonary edema (increased hydrostatic pressure in blood vessels) + Dyspnea, Paroxysmal Nocturnal Dyspnea (dyspnea if lay flat over hours), Orthopnea (dyspnea if lay flat over a few minutes), crackles (edema or fluid within interstitial space of lung)

+

Heart failure cells: rupture of engorged capillaries –> blood leaks out of capillaries into alveolar airsacs –> macrophages of alveolar airsacs consume that blood –> consume lots of iron which piles up into macrophages
“Hemosiderin laden macrophages”

Decreased forward perfusion
1. activation of renin angiotensin system
(decreased perfusion of kidneys –> juxtaglomerular apparatus activated –> renin release –> converts angiotensinogen to angiotensin I –> ACE converts angiotensin I to angiotensin II –> angiotensin II constricts arterioles (increase TPR) and goes to adrenal gland which releases aldosterone –> kidney resorbs Na+ and water follows (inc blood volume)
2. mainstay of treatment is ACE inhibitor

Question 1

Causes of Left-sided heart failure

Answer 1

Ischemia: decreased bloodflow to myocardium
Hypertension: concentric LV hypertrophy (2/2 increased stress); harder to oxygenate thicker wall
Dilated cardiomyopathy: 4-chambered dilatation of heart, stretches muscle (not able to contract as well)
Myocardial infarction: myocardium not functioning
Restrictive cardiomyopathy: cannot fill heart appropriately, not able to pump blood appropriately

Question 2

Causes Right-sided heart failure

Answer 2

Most commonly due to left-sided heart failure!
(backup of blood from LV into pulmonary circuit goes to RV)

other:
1. left to right shunt= if shunt from LV to RV, increase amt of blood into RV (inc risk of R heart failure)
2. chronic lung disease (cor pulmonale)= if lung disease then develop hypoxia (one consequences of hypoxia is constriction of blood vessels in lung)
if hypoxia throughout lung blood vessels of entire lung constrict and RV must contract against)
cor pulmonale: R heart eventually fails against increased resistance from lung

Question 3

Clinical features of Right sided heart failure

Answer 3

Due to Congestion of things that feed into Right Heart!!!

1. Jugular vein –> Jugular venous distension
2. Venous system from liver and spleen –> painful hepatosplenomegaly, may lead to cardiac cirrhosis (can be consequence of longstanding congestion of liver)
3. Lower extremities also drain into R heart –> increased hydrostatic pressure in lower extremities –> Dependent pitting edema