ITE CA2 Cardiac Flashcards
dP/dt
dP/dt (the rate of rise in ventricular pressure) is a good measure of cardiac contractility. Pressures can be measured directly (in the cath lab) or estimated by echocardiography (using the simplified Bernoulli equation). Requires mitral regurg
Sphericity index
Sphericity index (long axis/short axis) is normally >1.5. It is reduced in dilated cardiomyopathy (the LV becomes more globular)
Factors that can result in variable ACT include
Factors that can result in variable ACT include: hemodilution, hypothermia, platelet counts below 30-50 k/mL, and concomitant administration of other medications which affect platelets (e.g. prostacyclin, aspirin, glycoprotein IIb/IIIa inhibitors).
What happens when ultrasound reaches an interface of two tissues with different acoustic impedance?
Acoustic impedance is the capacity of a tissue for transmitting sound. Water and soft tissues have intermediate acoustic impedances, while bone has a high acoustic impedance and air has a low acoustic impedance.
When ultrasound reaches an interface of two tissues with different acoustic impedance (soft tissue-air or soft tissue-bone), most of the ultrasound will be reflected.
Reflection is the basis for correct image formation. Reflection is maximal when the angle of incidence between the beam and the reflecting structure is 90 degrees (giving sharper images).
cranial nerve for carotid sinus baroreceptor reflex
IX Glossopharyngeal
What serum biomarker is first to reach peak after myocardial injury
myoglobin
acute STEMI best identified by wich leads
II, II, aVF
EKG changes with hypocalcemia
prolong QT
in 60% of population this artery supplies blood to SA node
R coronary
ST segment cahnges with sub-endocardial ischemia
ST segment depression
bainbridge reflex
causes increase in HR in response to increased RA fiber pressure and stretch
T wave corresponds to
ventricular repolarization
NYHA class II
excessive fatigue and dyspnea with ordinary activity
concentric hypertrophy of heart ass’d with what type of overload
pressure
sensitivity for combination of EKG leads II and V5 for detecting MI evnts
80%
phase of cardiac myocyte action potential correspond to influx of calcium
2
PEEP effect on venous return to heart
decrease
delta wave
wolff parkinson white
heart sound rapid ventricular filling
S3 - abnormal in all elderly patients
Beck’s triad
for pericardial tamponade
hypotension
muffled heart sounds
JVD
EKG lead best detect right sided arrhythmogenic treacings
II
which papillary muscle has a single-vessel blood supply
posterior
Refraction
Refraction is a source of artifact that occurs when the ultrasound direction is altered. Like reflection, it occurs when the ultrasound reaches an interface of two tissues of different acoustic impedance. Unlike reflection, refraction is most pronounced when the angle of incidence is acute. Thus, a 90 degree angle not only produces sharper images but also reduces artifacts.
How to close or open a PDA
Prostaglandin E1 helps maintain a PDA whereas indomethacin (nonselective COX inhibitor) is the standard medical treatment for closure of a PDA by inhibiting prostaglandin synthesis. Ligation of a PDA is the surgical treatment of choice if medical therapy has failed. Closure results in higher systemic pressures (especially higher diastolic pressures) and patients may require antihypertensive therapy postclosure.