Previous exam 2000 Flashcards
How do you calculate aortic and mitral valve effective orifice areas
generally 2 possible ways
Invasive hemodynamics
Echocardiographic findings.
What is Gorlin formula
Based on Cath data
works for stenotic valves only (need to have a stenosis to detect a gradient)
Basic principle is that flow = area x velocity
Velocity = square toot of change of pressure x constatn
Not valid in the presence of AI
AVA = AVF/44.3 (c) square root of pressure gradient
valve area = cardiac output/square root of pressure gradient.
What is continuity equation
determined echocardiographic
tends to underestimate valve area compared to Gorlin equation’
AVA = stroke volume
- -------------------- * eT (85) Vmean
Et = ejection time Vmean= mean flow velocity just distal to valve
List 3 indications for retrograde carioplegia
severe proximal coronary artery disease (unable to administer adequate antegrade plegia)
re-op situation with patent arterial grafts and proximally occluded native vessels
re-op coronary surgery to avoid thromboemboli down disease vein grafts
complex mitral valve surgery
aortic valve/root surgery–theory that retrograde cardioplegia provides better perfusion to subendocardium in LVH than antegrade cardioplegia
Aortic insufficieny
List 6 complications of a child with untreated VSD
Bacterial endocarditis
RV outflow tract obstruction secondary to infundibular muscular hypertrophy (RV muscle bundles)
Aortic insufficiency
Pulmonary hypertenion/TR/RVH/Right heart failure/Eisenmengers’ complex
failure to thrive
congestive heart failure
Indications for surgery in acute type B dissection
Failure of medical management refractory pain refractory hypertension proximal extension of dissection Visceral compromise Rupture/Leak Aneurysmal size greater then 6.5 cm
List 5 predisposing factors for type A dissection
Connective tissue disorder Bicuspid or unicuspid aortic valve hypertension coarctation of the aorta pregnancy
Intra-operative risk factors for AV groove separation in MVR
non preservation of the posterior apparatus
over sizing the valve
excessive traction on annular sutures
dislocation of the heart to inspect grafts post MVR
excessive traction on the papillary muscles
misplacing post of bioprosthesis (into the the posterior wall of LV)
What is angiographic grading of AI
0 = No AI
1+ dye does not fully opacity entire LV, clears with each systole
2+ fully opacifies LV but clear with each systole
3 + as dark as aorta does not clear with each systole
4 + darker than aorta does not clear with each systole
Angiographic grading of MR
0 = NO MR
1+ does not fill LA, clears with each systole
2+ fills LA less opacity then LV does not clear with 1 systole
3+ fills LA as dark as LV
4+ fills LA darker than LV increased with each systole (pulmonary veins also fill)
List mechanism of FK506 and ATGAM
FK506 (tracro) inhibits calcineurin which blocks transcription of IL2 which is needed for T cell activation
ATGAm–anitthymocyte gobulin that is introduced into humans and directly blocks t cells.
What is classification of vascular rings
Complete ring
double aortic arch
right dominant aortic arch with left ligamentum
Incomplete ring
inominate artery compressure syndrome
pulmonary artery slight (RPA from LPA behind the traches
abberant right subclavian.
List reasons why you cannot ventilate a patient after a CABG
ETT disconnected ETT blocked ETT moved bronchospams collpased lung compressed lung pulmonary edema
What is predictability of biventricular repair in PA/IVS
depends on two factors
presence of a right ventricular depenent coroanary circulation (which prohibits biventricular repair)
The ability of the RV to provide adequate pulmonary blood flow at normal filling pressures. Must decompress RV with RVOT procedures (patch or valvotomy) to encourage growth of RV.
TV size is a good measure of RV volume.
What are tricuspid valve z scores that will allow biventricular repair to occur for PA/IVS
- TV (Z = 0 to 2) perform RVOT procedure alone. No increased mortality. The need for subsequent shunt is low (RV can provide adequate pulmonary blood flow)
- TV (Z = -2 to -2) the chance of biventricular repair decreases as tricuspid annuls diameter decreases. Suggest RVOT procedure+ shunt (low chance of mortality and subsequent procedure). Good pulmonary blood flow, Right ventricle growth, Shunt can be taken down percutaneously
- TV (Z < 3. Shunt alone. Less mortality then if an RVOT procedure was attempted. in CHSS data, no patient withe Z score < 3 survivied biventricular repair.
