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
A loud pulmonic component of S2 and an accentuated, palpable impulse at the left sternal border (left parasternal lift) is seen with what condition?
Pulmonary HTN
Which mutation is the most common cause of familial dilated cardiomyopathy?
Truncating mutations (usually nonsense) affecting TTN gene encoding for the sarcomere protein titin
Myxomatous changes with pooling of proteoglycans in the media layer of large arteries are found in cystic medial degeneration, which predisposes to the development of what; commonly seen in association with what syndrome?
- Aortic dissections and aortic aneurysms
- Medial degeneration is commonly seen in younger pt’s with Marfan syndrome
Which type of angina is more common in younger pt’s (<50) and is characterized by recurrent chest pain at rest or during sleep which resolves in 15 mins or less?
Vasospastic angina (aka Prinzmetal)
Where is the most deoxygenated blood in the body found and why?
- Cardiac venous blood in the coronary sinus
- O2 extraction from the blood by resting myocardium is higher than that extracted by any other tissue
Holosystolic murmurs can be associated with what 3 conditions?
- Tricuspid regurgitation (TR): increases w/ inspiration
- Mitral regurgitation (MR): radiates to axilla
- Ventricular septal defct (VSD): loud and accompanied by thrill
What structure does a venous catheter traveling from the right femoral vein pass through to get into the left atrium?
Interatrial septum at the site of foramen ovale
Why are inferior MI’s often associated with bradycardia?
Due to blockage of RCA, which is responsible for perfusing the SA and AV nodes
Coronary dominance is determined by what; what is a right vs. left dominant heart?
- Determined by the coronary artery that supplies blood to the posterior descending artery (PDA)
- Right coronary artery: 70% of population = right dominant
- Left circumflex artery: 10% of population = left dominant
How is the murmur associated with hypertrophic cardiomyopathy best differentiated from that of aortic stenosis?
- Using maneuvers that affect LV preload
- Maneuvers such as valsalva, rapid standing, and infusion of nitroglycerin all decrease LV preload —> increasing intensity of hypertrophic cardiomyopathy
- Maneuvers such as passive leg raise or squatting lead to increased LV preload –> increasing intensity of aortic stenosis
Blunt aortic injury (i.e., traumatic aortic rupture) is most commonly associated with injury to which part of the aorta?
Aortic isthmus, which is tethered by the ligamentum arteriosum
In patients with mitral regurgitation what is the best indicator of severe MR with left-sided volume overload?
Audible S3 gallop
Nonbacterial thrombotic endocarditis (NBTE) is most commonly associated with which 2 underlying conditions?
- Advanced malignancy: especially mucinous adenocarcinoma
- SLE –> Libman-Sacks endocarditis
What is the most common underlying valvular disease predisposing to the development of infective endocarditis in developed countries?
Mitral valve prolapse (MVP), particularly when it is associated with coexistent mitral regurgitation
