4. Cath Flashcards
Equation for Qs (indexed systemic flow)?
Qs = VO2/[(SA-MV)(Hgb)(13.6)]
When can you ignore dissolved pO2 in the systemic flow equation?
When patient in room air
Can’t see LPA on a TTE… angiograms with moderate enlargement of the RV and severe RVOT obstruction… diagnosis?
ToF
- Hypoplasia of main and branch PAs
- Also get R-L shunting through VSD with opacification of aorta
Diagnosis if femoral vein catheter courses posterior over vertebral bodies cranially then takes an anterior turn?
Interrupted IVC
-Catheter in azygous bein with anterior turn at anastomosis with SVC
When do you see azygous continuation into a right or left SVC?
Interrupted IVC
What embryologically causes interrupted IVC?
Failure to form the right subcardinal-hepatic anastomosis
What results in a prominent V-wave on RA pressure tracing?
- Gerbode defect
2. Ebstein anomaly (severe TR)
Why does a Gerbode defect and severe TR cause a prominent V wave on RA pressure tracing?
Enhanced RA filling during AV valve closure through ventricular systole
When would you see a prominent A wave on an RA pressure tracing?
Lesions causing RV diastolic dysfunction or obstruction to RV inflow (tricuspid stenosis)
What is indicated if you have a change in arterial pressure waveform and JVD during cathterization?
Pericardiocentesis
-Likely a hemopericardium from complication due to cath
What should you consider with rapid onset hypotension and tachycardia during cath?
Impaired CO due to cardiac tamponade
Headaches and urticaria following Amplatzer septal occluder placement…?
Nickel allergy
-Rare, but can happen
What is the metal frame of an Amplatzer device made of?
Nitinol (nickel-titanium alloy)
True or False: Detectable levels of nickel have been identified in the bloodstream after successful Amplatzer device placement?
True
True or False: Most conduction abnormalities following ASD device closure resolve within 7 days of device placement
False- 24 hours
-Most abnormalities resolve, especially in children
What % of patients can have ECG abnormalities after ASD closure?
5-10%
Do older patients or children have a higher incidence of ECG abnormalities after ASD device closure?
Older patients
Equation for Qp:Qs?
(SA-MV)/(PV-PA)
Equation for volume of a L-R shunt?
QL-R = Qp - Qep
Qp = VO2/ [1.36 * 10 * Hgb * (PV-PA)]
Qep = VO2/ [1.36 * 10 * Hgb * (PV-MV)]
Equation for volume of a R-L shunt?
QR-L = Qs - Qes
Qs = VO2 / [ 1.36 * 10 * Hgb * (Ao-MV)]
Qes = VO2/ [1.36 * 10 * Hgb * (PV-MV)]
True or False: Effective pulmonary blood flow (Qep) = Effective systemic blood flow (Qes)
True
Equation for PVR?
PVR = (PAmean-LAmean)/Qp
What is the transpulmonary gradient?
PAmean-LAmean
What diagnosis:
- Pulmonary HTN
- Increased PA sat (L-R shunting)
- Systemic arterial desaturation (R-L shunting)
- Widended pulse pressure
Truncus Arteriosus
What should you consider with RV and LV saturations that are significantly different, but PA and aortic sats that are the same?
Truncus arteriosus
*Most of the mixing is at the level of the great arteries
True or False: ToF will have similar systemic and PA saturations
False: ToF has different systemic and PA saturations due to preferential streaming of blood in the ventricles to the ipsilateral great artery
Which saturation is higher in a PDA with Eisenmenger… ascending aorta or descending aorta?
Ascending
-Will get R-L shunting at PDA
True or False: IAA + PDA can cause pulmonary HTN and descending aorta desaturation
True
*Ascending aorta sat should be normal
True or False: TGA with a large ASD can cause enough mixing that the aortic and PA sats are the same
False: Can cause mixing of systemic and pulmonary venous blood, but not usually enough that aortic and PA sats are the same
What defect is associated with elongation of the LVOT?
AVSD
*Goose neck deformity
What causes the goose neck deformity in AVSD?
Anterior displacement of the aortic valve
What does an elongated LVOT in AVSD predispose a patient to?
Progressive subaortic obstruction
What % of kids with Down Syndrome have CHD?
40-45%
Of kids with Down Syndrome who have CHD, what % is an AVSD?
45%
Marfan and Loeys-Dietz are primarily what type of CHD?
Aortic disease
Supravalvar AS and branch PA stenosis?
Williams Syndrome
Large ASD creating a common atrium?
Ellis van Crevald
Most likely indication for cath in TGA?
Balloon atrial septostomy
When is a cath indicated for a newborn with TGA?
If there is severe hypoxia with inability to provide oxygenation via native atrial communication or via PGE
What is the usual site for connection of an anomalous left pulmonary vein?
Innominate vein (via vertical vein)
What are lesson common sites of PAPVR of the LPV (innominate most common)?
- Coronary sinus
- Right SVC
- Left SVC
- Azygous
True or False: A vertical vein is separate embryologically from a left-sided SVC
True
What does a L-SVC typically drain to?
CS
Is an L-SVC typically anterior or posterior to the LAA?
Posterior
What lesion do you think of for a teen with severe pulmonary HTN and significant step-down in saturation from the ascending aorta to descending aorta?
PDA or AP window with R-L shunt
What situation can you not use the Fick principle to calculate pulmonary blood flow?
Multiple sources of pulmonary blood flow with different O2 content
Ex: ToF with surgical AP shunt
What situation can you not use the Fick principle to calculate systemic blood flow?
Multiple sources of systemic blood flow with different O2 content
Ex: PDA with flow from ascending aorta and ductus
PVR equation?
(Mean PA pressure - Mean La pressure) / Qp
Equation for dissolved O2?
0.003 * pO2
How to factor in dissolved O2 to Qp?
- PV O2 content: 1.36 * Hgb * 10 * (PV sat%) + (0.03 * PO2)
- PA O2 content: 1.36 * Hgb * 10 * (PA sat%) + (0.03 * PO2)
Qp = VO2 / (PV O2 content-PA O2 content)
Bidirectional Glenn Connection?
SVC to cavopulmonary anastomosis communicating with RPA and LPA
What is a common complication of a Bidirectional Glenn?
Stenosis on left side of PA insertion of SVC
Classic BT Shunt Connection?
Right subclavian to RPA anastomosis with native vessel
Modified BT Shunt Connection?
Right subclavian to RPA with artificial material
Classic Glenn Connection?
RSVC to distal RPA supplying single lung
DKS Connection?
Transected MPA anastomosed with ascending aorta
What can sometimes be seen in pulmonary stenosis downstream?
Post-stenotic dilation of the MPA
What is a bulbous configuration of the origin of an aberrant left subclavian artery in a right-sided aortic arch or aberrant right subclavian artery in the setting of a left-sided aortic arch called?
Diverticulum of Kommerell
2 indications for PDA closure?
- Symptomatic PDA with L-R shunting
2. Asymptomatic PDA with LA or LV enlargement
How is CI calculated?
Fick equation
How is VO2 calculated?
Difference in blood oxygen concentration across the capillary bed
Equation for CI?
CI = VO2 / (1.36)(10)(Hgb)(Ao-MV)
How to calculate PVR when unequal pulmonary blood flow?
1/Rtotal = 1/Rright + 1/Rleft
*Use % differential flow * CI for QP then calculate each lung PVR using pressures and appropriate QP. Then plus into above equation.
Indication for ASD device removal?
If extends beyond borders of cardiac silhouette on CXR… know it has embolized in this situation
Why are patients with Williams syndrome at risk for sudden cardiac death during procedures requiring sedation?
Risk for coronary malperfusion and ischemia leading to ventricular dysfunction and impaired CO in the setting of supravalvular AS
Patients taking NPH insulin are at increased risk of a hypersensitivity reaction to what?
Protamine
What can be seen if you give protamine to someone taking NPH insulin?
Range of reactions:
-Back/flank pain, flushing, peripheral vasodilation, vasomotor collapse (can even be fatal)
What is a reason to have discrepant right and left pulmonary capillary wedge pressures?
Anomalous pulmonary veins on one side
*Side with anomalous drainage will be reflective of RA, side with usual drainage reflective of LA
What would you expect to find on catheterization in pulmonary vein stenosis?
Gradient between ipsilateral pulmonary capillary wedge pressure and LA/LVEDP
What is typically seen with anomalous pulmonary venous drainage to a left innominate vein?
Draining left vertical vein
What defect is seen more commonly with a sinus venosus ASD?
Anomalous right pulmonary veins draining directly to the SVC or RA
What is often seen in Scimitar syndrome with regards to the pulmonary veins?
Pulmonary sequestration (anomalous pulmonary vein drains inferiorly to the IVC)
What defect is more commonly associated with a persistent left SVC?
Unroofed coronary sinus
Risk of device erosion after closure of secundum ASD?
1/1000
What can cause device erosion following ASD closure with an Amplatzer septal occluder?
Oversizing and impingement on wall or aorta
*Can also see with smaller devices too
What type of ASD device has not been associated with erosion?
Gore Helex
What early to mid-term complication is more likely to occur from balloon angioplasty than stent implantation or surgical repair for coarctation of the aorta?
Acute aortic wall injury
What type of repair for older patients with coarctation of the aorta has the lowest rate for acute complications?
Stent (single study)
If you see an anomalous right upper pulmonary vein draining to the right SVC and then RA, what should you consider?
Sinus venosus ASD
What is right upper PAPVC most commonly associated with?
Superior sinus venosus ASD (deficiency of the common wall between the right SVC and RUPV (results in LA orifice of RUPV with an unroofed pulmonary vein)
3 things that can be seen with right upper PAPVC?
- Superior sinus venosus defect
- Secundum ASD
- Persistent LSVC
Anomalous drainage of the right pulmonary veins to the IVC, just above or below the diaphragm?
Scimitar
Qp:Qs equation
(Ao-MV)/(PV-PA)
What can be used as a surrogate for MPA pressure?
PV wedge pressure
PVR equation
(PAmean-LAmean)/Qp
What can be used as a surrogate for LA pressure?
PA wedge pressure
Right subclavian to RPA anastomosis with native vessel?
Classic BT shunt
Right subclavian to RPA anastomosis with artificial material?
Modified BT shunt
Direct descending aorta to LPA anastomosis?
Potts
Direct ascending aorta to RPA anastomosis?
Waterston
In which atrium is the A wave higher than the V wave?
RA
In which atrium is the V wave higher than the A wave?
LA
What causes a v wave?
Atrial filling with a closed AV valve during LV constrction
What happens to the v wave in left AVVR?
Increased (blood flows back to LA through regurgitant orifice)
When would you expect to see an increased A-wave?
MS
LV diastolic dysfunction
In severe left AVVR, what would be accentuated on pulmonary capillary wedge tracing?
C wave
What does the C wave correspond to on RA waveform?
Tricuspid valve closure with bowing of valve to atrium
A wave on RA waveform?
Atrial contraction
C wave on RA waveform?
Closure of AV valve with bowing of AV valve into the atrium during the start of the ventricular contraction
X-descent on RA waveform?
Descent in pressure as the AV valve ring is pulled into the ventricle
V wave on RA waveform?
Passive filling of atrium with a closed AV valve
Y-descent on RA waveform?
AV valve opening and passive atrial emptying
What things decrease Hgb affinity for O2?
- Increase in pCO2
- Increase in 2,3-BPG
- Increase in H+ (decreased pH/acidosis)
- Increase in temperature
Decreased Hgb affinity for O2 results in what?
- Right shift in oxyhemoglobin curve
- Increased partial pressure of O2 in tissue
What has the highest O2 extraction?
Coronary arteries
*Need to supply myocardial O2 demand
Venous blood from what structure entering the RA has the lowest saturation?
CS
*Coronaries have highest O2 extraction to meet myocardial O2 demand
Coronary sinus return makes up what % of systemic venous return?
5-7%
What is the typical saturation of blood returning from the CS?
25-45%
What is a potential cause for a very low mixed venous saturation?
Catheter too close to or in CS
*This has lowest venous saturation returning to RA and if oversampled can misrepresent the MV saturation and make it seem like there is a shunt lesions when there isn’t
How does thermodilution work?
- Uses a temperature indicator and fixed volume of fluid to measure the downstream change in temperature
- The area under the temp-time curve is used to determine CO
What are advantages of thermodilution?
- Accurate/reproducible results
- Short steady state time requirement
- Only need for venous access
What are sources of error in thermodilution?
- Discrepancy in low CO
- AVVR
- Intracardiac shunting (Qp doesn’t equal Qs)
What should be done prior to cath for a patient with a Hct of 75%?
- Prehydration (also can help with renal insufficiency issues with NPO/Angios)
- Consideration of phlebotomy in cath lab
What effect does polycythemia have on O2 carrying capacity and O2 delivery?
- Increases O2 carrying capacity
- Decrease CO and O2 delivery to tissues
What does polycythemia increase risk for?
Thrombosis and emboli
What cath features are more suggestive of restrictive cardiomyopathy v. constrictive pericarditis or tamponade?
- RVSP >50 mmHg
- LVEDP – RVEDP >4mmHg
- PVWP- mean RAP > 4mmHg
- RVEDP/RVSP <0.3
Which finding on RA waveform consistent with diagnosis of restrictive cardiomyopathy rather than constrictive pericarditis?
Normal respiratory variation in mean RA pressure
- There will continue to be respiratory variation in the mean RA pressure in restrictive cardiomyopathy rather than constrictive pericarditis
- Constrictive pericarditis will result in an inspiratory rise or lack of decline in RA pressure (Kussmaul sign)
True or False: M waves can be seen in constrictive pericarditis and restrictive cardiomyopathy
True
Equalization of ventricular end diastolic pressure is diagnostic for what?
Constrictive pericarditis
Absence of A waves on a RA waveform tracing should raise concerns for what?
Arrhythmia (a-fib or a-flutter)
Qp:Qs equation?
(Ao-MV)/(PV-PA)
If you see a CXR with heavily calcified pericardium, what type of physiology do you expect?
Constrictive
What are cath markers of constrictive physiology?
- Elevated LVEDP
- Elevated mean PCWP
- Elected RVEDP
- Elevated mean RA pressure
During cath, if you see low saturation in the left pulmonary veins, but normal saturation in the right pulmonary veins, what should you check?
ETT position
*If ET tube in right mainstem bronchus, left lung may be ineffectively ventilated/oxygenated
DOE and orthostatic (worse standing) or exertional cyanosis in a Fontan patient can occur due to R-L shunting at what 2 places?
- Patent fenestration
2. Pulmonary AVM
Where do pulmonary AVMs most commonly occur?
Basal region of lung
What gradient in an asymptomatic adult is a class I indication for pulmonary balloon valvuloplasty?
Over 40mmHg cath peak to peak or mean Doppler
An asymptomatic 20 y/o with mean PV Doppler gradient 24mmHg, 30 y/o with refractory migraines and PFO, 25 y/o asymptomatic with continuous murmur and small PDA on echo, 28 y/o with small membranous VSD and recurrent endocarditis are all what class indications for cath intervention?
Class II
In aortic stenosis, what size balloon should be used for valvuloplaty?
Smaller then valve annulus… risk of post-procedure valve regurgitation if balloon exceeds 100% of annulus diameter
For pulmonary balloon valvuloplasty, what size should the balloon be?
Between 120-140% of the PV annulus diameter
In an acidotic infant with d-TGA what should be done first after obtaining vascular access for BAS?
The BAS (before any RV angiography or other diagnostics)
Where does mixing primarily occur in patients with complete TGA?
Atrial level
*Even with a VSD, the patient can be profoundly cyanotic and acidotic requiring a septostomy
What are 2 reasons an ASD can’t be closed in the cath lab?
- Defect is too large (esp relative to patient size/overall length of septum)
- Deficient rims
What needs done prior to PDA closure in a child with a large PDA and bidirectional shunting?
- Hemodynamics to assess for pulmonary vasoreactivity
* Occlusion may be beneficial only if pulmonary lung bed shows some reactivity to pulmonary vasodilator therapy
What % of PA-IVS patients have coronary abnormalities?
5-35%
What types of coronary abnormalities are seen in PA-IVS?
- RV sinusoids
- Coronary-cameral fistulae
- RV-dependent coronary circulation (significant portion of LV supplied by fistulae fed by hypertensive RV)
What can happen is you decompress an RV in the setting of significant RV-dependent myocardial circulation?
Irreversible myocardial ischemia (usually fatal)
Pulmonary valvuloplasty is a class I indication for what?
- Critical PS (present at birth, cyanosis, ductal-dependent)
- Valve with peak to peak cath or peak echo >40mmHg
- Clinically significant pulmonary valvar obstruction with RV dysfunction
What is a class I indication for ASD device closure?
Hemodynamically significant ASD with suitable anatomic features
What are 2 class IIa indications for ASD device closure?
- ASD with transient R-L shunting and sequalae of paradoxical emboli like stroke or recurrent TIA
- ASD with transient R-L shunting and cyanosis who don’t need pop-off
What is a class IIb indication for ASD device closure?
ASD at risk of thromboembolic events (transvenous pacing system, indwelling catheters, hypercoaguability)
What are the 2 main reasons to do a BAS?
- Improve mixing (d-TGA)
- Improve ASD restriction with obstruction or stenosis of AoV (HLHS)
*Rarely needed in right heart obstructive lesions
Why do you have to be cautious if doing a BAS for tricuspid atresia?
Redundant atrial septum can disrupt the RA/IVC junction
Is a BAS ever done for TAPVR?
No- septum isn’t usually location of obstruction
Is a BAS more straightforward for d-TGA or HLHS?
d-TGA: Flap of fossa ovalis is thin and easy to tear with balloon catheter
*BAS can be performed up to a few weeks of age (after this, atrial septum may be too thick to balloon successfully in any lesion without significant risk of disruption of normal tissue… blade septosotmy will then be needed)
What is the risk of BAS in HLHS?
- Tissue may be very thick with minimal to no opening at time of delivery
- Procedure usually done emergently and immediately after delivery
- May require various techniques (transseptal or radiofrequency access to LA, use of dilation balloon (cutting) and stent placement)
- Simple balloon septostomy in HLHS with thick restrictive atrial septum may avulse the pulmonary veins (tissue with least resistance will give way) during BAS
What should be considered as a cause of exertional cyanosis in a patient s/p Mustard?
R-L shunt via baffle leak
What should be done for a baffle leak?
Closure either via surgery or in the cath lab with a septal occluder device
What cath-based intervention can be done for baffle obstruction s/p Mustard?
Stent placement
What are factors which may affect the pressure gradient across a coarctation?
- LV dysfunction with low CO
- Large PDA
- Multiple collateral decompressing the aorta
DCM, endocardial fibroelastosis, proximal skeletal myopathy, growth failure, neutropenia, organic aciduria
Barth syndrome (X-linked)
*3-methylglutaconic aciduria type II
What needs done prior to a cath for someone with Barth syndrome?
CBCdiff to assess for neutropenia, may need G-CSF and may adjust antibiotics as indicated