Cardiovascular Flashcards
Coronary autoregulation allows coronary blood flow to be primarily driven by myocardial O2 demand over a wide range of perfusion pressures (60-140 mmHg) and is controlled via release of what?
Adenosine and NO
How do you calculate stroke volume (SV) and ejection fraction?
- SV = EDV - ESV
- EF: Stroke Volume / EDV
Which acid-base physiological changes are seen when patient is at high altitude and develops altitude sickness?
- Low PiO2 –> compensatory hyperventilation –> respiratory alkalosis
- Kidneys respond by decreasing HCO3- reabsorption and H+ secretion —> compensatory metabolic acidosis
Sick sinus syndrome most commonly results from what; describe the findings seen on ECG?
- Age-related degeneration of the SA node, located in the RA wall
- ECG findings = bradycardia, sinus pauses (delayed P waves), and sinus arrest (prolonged delayed of a P wave such that P wave is dropped)
Which type of breathing pattern is often seen in pt’s with advanced congestive heart failure (CHF)?
Cheyne-Stokes breathing: cyclic breathing pattern in which apnea is following by gradually increasing and then decreasing tidal volumes until next apneic period.
Atrial septal defects with left-to-right shunting typically cause what ausculatory finding on PE?
Wide and fixed splitting (no change with respiration) of the 2nd heart sound (S2)
How can a paradoxical embolism arise in a patient with net left-to-right shunting?
Transient reversal of the shunt during periods of elevated right-sided pressure (i.e., early ventricular systole, straining during coughing or defecation)
The inferior wall of which ventricle forms the majority of the inferior (diaphragmatic) surface of the heart and what is its blood supply?
Inferior wall of LV supplied by posterior descending a. - branch of the right coronary a. (RCA)
10% of people have left dominant circulation meaning the posterior descending artery derives from where?
- Circumflex branch of the left main coronary a.
*Typically arises from right main coronary a.
Which artery supplies the wall of the RV and may provide collateral circulation in pt’s with LAD occlusion?
Right marginal branch of the RCA
Occlusion of the right coronary artery may affect which areas of the heart during MI?
- LV due to inferior wall being supplied by posterior descending a. arising from RCA
- RV due to marginal a. arising from RCA
What is the hallmark murmur heard with mitral valve prolapse (MVP)?
Mid-systolic click, often accompanied by late systolic murmur
Immunohistochemistry is important diagnostic marker for mesothelioma as nearly all cases stain (+) for what?
Cytokeratins and many also (+) for calretinin
When does papillary muscle rupture following an MI typically occur and what are the distinct PE findings?
- Within 3-5 days
- Acute, severe pulmonary edema + severe mitral regurgitation w/ flail leaflet
What are the distinct PE findings of an interventricular septum rupture/defect following an MI?
- New holosystolic murmur
- Stepped-up O2 level between the RA and ventricle