Cardiac Flashcards
This represents?
A normal JVP
CVP waveforms:
a-wave: atrial contraction, “Atrial”
c-wave: ventricular contraction, “triCuspid”
v-wave: atrial filling, “Villing”
x-descent: ventricle emptying, atrial relaxation, “relaXation”
y-descent: atrium emptying, “emptYing”
This represents?
Constrictive pericarditis (will see similar pattern in RV ischemia)
CVP waveforms:
a-wave: atrial contraction, “Atrial”
c-wave: ventricular contraction, “triCuspid”
v-wave: atrial filling, “Villing”
x-descent: ventricle emptying, atrial relaxation, “relaXation”
y-descent: atrium emptying, “emptYing”
This represents?
Complete AV block
CVP waveforms:
a-wave: atrial contraction, “Atrial”
c-wave: ventricular contraction, “triCuspid”
v-wave: atrial filling, “Villing”
x-descent: ventricle emptying, atrial relaxation, “relaXation”
y-descent: atrium emptying, “emptYing”
This represents?
Cardiac tamponade
CVP waveforms:
a-wave: atrial contraction, “Atrial”
c-wave: ventricular contraction, “triCuspid”
v-wave: atrial filling, “Villing”
x-descent: ventricle emptying, atrial relaxation, “relaXation”
y-descent: atrium emptying, “emptYing”
This represents?
Tricuspid stenosis
CVP waveforms:
a-wave: atrial contraction, “Atrial”
c-wave: ventricular contraction, “triCuspid”
v-wave: atrial filling, “Villing”
x-descent: ventricle emptying, atrial relaxation, “relaXation”
y-descent: atrium emptying, “emptYing”
This represents?
Atrial fibrillation (notice loss of A-wave)
CVP waveforms:
a-wave: atrial contraction, “Atrial”
c-wave: ventricular contraction, “triCuspid”
v-wave: atrial filling, “Villing”
x-descent: ventricle emptying, atrial relaxation, “relaXation”
y-descent: atrium emptying, “emptYing”
ECG change that suggests hypOcalcemia?
prolonged corrected QT interval (QTc) in any lead
Well-described complications of radiofrequency catheter ablation for atrial fibrillation?
phrenic nerve injury and thermal injury to esophagus causing atrioesophageal fistula (due to close proximity to posterior left atrium of both structures)
avoid muscle relaxants so phrenic nerve stimulation may be more easily identified and continuous monitoring of esophageal temperature!
Where is an intra-aortic balloon pump positioned? when does it inflate? when does it deflate?
Positioned in the descending aorta.
Inflates during mid-diastole.
Deflates during systole.
ACT goal for cardiopulmonary bypass?
400-480 seconds (classically 480 seconds)
If ACT value is not appropriate for cardiopulmonary bypass after 2 appropriate heparin doses, what is the problem?
heparin resistance due to antithrombin III deficiency (likely iatrogenic):
give 2-3 units FFP or antithrombin III deficiency
cardiac parameter that is similar between the young and the elderly?
RESTING stroke volume is similar but elderly patients are unable to augment CO with EXERCISE due to diastolic dysfunction and decreased beta receptor sensitivity
goals of anesthetic management in cardiac tamponade?
Fast, full, tight
fast HR
full preload
maintain SVR
alpha stat pH at 18 degrees versus 37 degrees?
18 degrees: hypothermic alkalosis so PaCO2 diffuses into the blood and pH increases (pH~7.6 with PaCO2~16)
37 degrees: pH normalizes to 7.4
acid base status with pH stat at 18 degrees versus 37 degrees?
18 degrees: pH stat adds CO2 to the CPB sweep gas so that pH remains normal at 7.4
37 degrees: because CO2 is added, pH is acidotic when warmed to body temperature
Current literature favors pH stat over alpha stat because acidotic pH leads to cerbral vasodilation, higher cerebral blood flow and more efficient/uniform brain cooling
Type of hypertension that is a better predictor of CAD and mortality in YOUNGER patients?
Diastolic hypertension aka essential hypertension (DBP > 90)
Type of hypertension associated with increased risk of stroke, CAD and mortality in patients > age 60?
systolic and pulse pressure hypertension
systolic HTN = SBP > 140
pulse pressure HTN = pulse pressure > 65
**reflects arterial stiffening during the pulsatile component of the blood pressure
Diagnosis of PHTN requires what value determined by right heart catheterization? What is the NORMAL value?
MEAN pulmonary artery pressure > 25 mmHg at rest
Normal mean pulmonary artery pressures ~14 with an upper limit of 20
Which type of MI is most commonly associated with complete (3rd degree) heart block? Why?
inferior wall MI because the RCA also supplies the AV node
Common type of MI intraoperatively?
Type II - demand ischemia (versus type I from acute thrombosis)
3 main determinants of myocardial oxygen demand?
HR
contractility
wall tension (Laplace law T=PR/h)
formula for cardiac perfusion pressure?
CPP = AoDP - LVEDP
Anesthetic management goals for cardiac tamponade?
“Full fast and tight”
Maintain HR bc cardiac output becomes mostly HR dependent
Maintain SVR
Maintain spontaneous breathing (PPV can cause CV collapse)
When is the left ventricle perfused?
only diastole
When is the right ventricle perfused?
peak/late systole and early diastole bc pressures needed to overcome gradient on right side is lower (than in left side which only perfuses during diastole)
Main determinants of myocardial supply?
arterial oxygen content: CaO2 = (Hgb * 1.34 * SaO2) + (0.003 * PaO2)
cardiac perfusion pressure = AoDP - LVEDP
Drug of choice for bradycardia in transplanted heart?
isoproterenol or epinephrine because directly act on cardiac receptors; anticholinergics and ephedrine ineffective
Management of bradycardia during carotid stent deployment (common occurrence) that can lead to life-threatening hypotension?
glycopyrrolate prophylactically (better than atropine)
also transcutaneous/transvenous pacing