How could you raise the stroke volume?
Increase preload or contractility
Most important equation
Pressure (MAP) = Flow (CO = HR x SV) x R (TPR)
What is the ejection fraction?
What do you do when you encounter heart failure with low ejection fraction? How do you do it?
Reduce the afterload via 1 of 2 determinants: left ventricular size or SBP
Dilated ventricle is a big part of this (afterload)
What does aortic regurgitation cause?
Volume overload leading to eccentric hypertrophy
What are the 2 mechanisms of dysrhythmias?
Automaticity and reentry
What things alter automaticity?
Digoxin, hypoxia, CO2, acidosis, hypokalemia, low magnesium
Alter phase 4 of the AP such that it reaches threshold
What are the prerequisitites for reentry?
Two continuous pathways with different conduction velocities
What does it mean if you have JVD, barely palpable BP, and pulse that goes away with inhale (i.e., pulsus paradoxus)?
IV septum has received inspiratory volume, ventricle has tried to expand, but can't, so IV septum imposes on LV, decreasing stroke volume
What are the signs of heart failure with a low EF? How do you fix this?
Laterally displaced PMI, larger than a dime or nickel, S3
Renin, angiotensin up
ACEI: decreases afterload (have to check serum potassium in 1 week b/c worried about hyperkalemia) -> should increase CO
What is the stress-exercise test for?
Test to diagnose CAD
What is stable CAD? How does it progress?
Supply-demand mismatch due to coronary narrowing
2 major determinants of O2 demand: HR and SBP (both of which INC during exercise; this is why you do a stress test)
Coronary angiogram: stable, fixed stenosis (usually about 70%)
3 MONTHS LATER: elephant sitting on chest -> rupture of plaque, leading to MI
How do you confirm aortic regurgitation?
Confirm via echo
LV will adapt via eccentric hypertrophy
How do you detect aortic stenosis?
Bell of stethoscope right underneath right clavicle
Concentric hypertrophy og LV
Risk for CAD development
How do you determine if person with mitral stenosis needs to be sent to sx?
Gradient: difference b/t LA and LV in diastole (normal is 0); can be measured via Doppler echo
Flow across valve: echo (flow affects CO)
How do you tell if mitral regurgitation is acute?
Echo, cath to look for lack of adaptation (eccentric hypertrophy) and/or marked elevation of pressure upstream (i.e., LA, pulmonary vein or capillary)
What are the big risks with bacterial endocarditis?
Embolism (tricuspid to lungs; mitral to brain, kidneys, legs, coronary/MI)
Acute regurgitant lesions (i.e., chew up chordae tendineae)
How do you detect pericarditis?
Feel better when they lean forward
What causes sudden cardiac death? What if they survive?
What does mitral regurg sound like? Most common cause?
Systolic blowing murmur at the apex
Mitral valve prolapse (often has a distinctive click)
Asymptomatic mitral regurg patient with no eccentric hypertrophy about to have dental procedure? What do you do?
Give her 4 amoxicillin an hour before
What are some causes of ST elevation in absence of CAD?
Cocaine, vasospasm, hematocrit of 12 (anemia), aortic stenosis (not enough blood to coronary arteries), coronary emboli