Cardiac Flashcards
Crista terminalis
A muscular ridge in the right atrium that runs from the entrance of the SVC to the entrance of the IVC
Note: Do not confuse this right atrial structure with a clot.
Where are pectinate muscles found?
- Right atrium (running from the peak of the crest terminals to the right atrial appendage)
- Left atrial appendage (inner surface only)
Eustachean valve
IVC valve that looks like a little flap in the distal IVC
Note: If this IVC valve appears more trabeculated, then its called a Chair Network.
What defines the right atrium?
The IVC entrance
What defines the right ventricle?
The moderator band
How do the ventricular outflow tracts differ?
The right ventricular outflow tract is muscular
The left ventricular outflow tract is fibrous (and continuous with the mitral valve)
Moderator band
A right ventricular structure that defines the right ventricle and acts as part of the right bundle branch electric system
Which cardiac view allows assessment of both the mitral and tricuspid valves?
The horizontal long axis (4-chamber) view
An AV canal defect is best seen on which view?
The horizontal long axis (4-chamber) view
Note: Most other congenital heart problems are better evaluated on other views.
The LV short axis view is perpendicular to the…
Horizontal long axis (4-chamber) view
The 3 chamber view is best for evaluating the…
Left ventricular outflow tract (e.g. for aortic regurgitation/stenosis)
What is the best MRI view for evaluating for aortic stenosis?
3 chamber view (of the left ventricular outflow tract)
What view is this?
Horizontal long axis (4-chamber) view
What view is this?
3 chamber view (of left ventricular outflow tract)
What view is this?
2-chamber long axis view
Widening of the carinal angle > 90 degrees on chest radiograph suggests…
Left atrial enlargement
Radiographic signs of left atrial enlargement
- Double density sign (2 superimposed right heart borders)
- Widening of the carinal angle > 90 degrees
- Elevation of the left main bronchus
- Walking man sign (splaying of the main bronchi on lateral radiograph making them looks like two legs walking)
Shifting of the right heart border by > 3 cm from midline on chest radiograph…
Suggestive of right atrial enlargement
On pre-natal ultrasound, the tech identifies an echogenic focus within the fetal left ventricle…
Likely a calcified papillary muscle that will resolve by the third trimester, but is associated with an increased risk of Down syndrome (look for other signs of Down syndrome)
Dumbbell appearance of billobed fat density in the atrial septum sparing the fossa ovalis…
Lipomatous hypertrophy of the interatrial septum
Lipomatous hypertrophy of the interatrial septum should spare the…
Fossa ovalis
Note: If the fossa ovalis is not spared, think lipoma.
Fat density in the interatrial septum without dumbbell appearance (i.e. does not spare the fossa ovalis)…
Think lipoma
Note: Lipomatous hypertrophy of the intertribal septum should spare the fossa ovalis.
You are thinking a fat density in the interatrial septum is lipomatous hypertrophy, but it is hot on PET/CT…
Lipomatous hypertrophy of the intertribal septum can be hot on PET (often made of brown fat)
Note: The important factor is whether it spares the fossa ovalis. If it does not, then think lipoma.
Lipomatous hypertrophy of the interatrial septum can cause…
Supraventricular arrythmias, but is otherwise inconsequential
Which coronary artery supplies the SA node?
The right coronary artery
Which coronary artery supplies the AV node?
The right coronary artery
The posterior descending artery is supplied by the…
- Right coronary artery (80%)
- Left coronary artery (20%)
What does the conus branch of the right coronary artery supply?
The ventricular outflow tract
Note: This is the first branch of the right coronary artery 50% of the time.
What are the main branches of the right coronary artery?
- Conus branch
- AV nodal branch
- Acute marginal branch
- Posterior descending artery (80%)
What are the main branches of the left coronary artery?
- Left anterior descending (with diagonal and septal branches)
- Left circumflex (with marginal branches and in 20% of people also the PDA)
Which coronary supplies the cardiac apex?
Left anterior descending
Which coronary supplies the cardiac septum?
LAD and Right coronary
Which coronary supplies the anterior LV wall?
LAD
Which coronary supplies the lateral LV wall?
Left circumflex
Which type of coronary anomaly should always get fixed?
LCA originating from the right coronary sinus
Note: If this doesn’t get fixed there is a high risk of sudden cardiac death.
Treatment for left coronary artery arising from the right coronary cusp
Surgical repair (to decrease risk of sudden cardiac death)
Treatment for right coronary artery arising from the left coronary cusp
Surgical repair only if symptomatic
What are the two most common causes of sudden cardiac death in young pts?
- Hypertrophic obstructive cardiomyopathy
- Malignant coronary artery with origin from the opposite sinus
ALCAPA
Anomalous left coronary from the pulmonary artery
What are the two types of ALCAPA
- Infantile (these pts die early from CHF and dilated cardiomyopathy)
- Adult (increased risk of sudden cardiac death)
Transient reversal of flow in the left coronary artery…
Think steal syndrome in the setting of ALCAPA (anomalous left coronary from the pulmonary artery)
Note: Flow reverses in the left coronary artery when pressure decreases in the pulmonary circulation.
Myocardial bridging
When a coronary artery dives into and courses through the myocardium
Note: This can complicate CABG planning.
Definition of coronary artery aneurysm
Dilatation of a coronary artery to 1.5x its normal diameter
Most common cause of coronary artery aneurysm in adults and children
- Atherosclerosis (adults)
- Kawasaki syndrome (children)
Coronary fistula
A connection between a coronary artery and cardiac chamber or great vessel (usually the RCA draining into the right cardiac chambers)
Note: This is associated with coronary aneurysms.
If you see crazy dilatation of coronary arteries…
Think coronary fistula with secondary formation of coronary artery aneurysms
What are the ideal indications for a coronary CTA?
- Intermediate risk for MI and/or atypical chest pain (to avoid unnecessary cardiac catheterization)
- Suspected aberrant coronary anatomy
- Evaluating stents >3 mm or CABG patency
- Preoperative assessment prior to TAVI/TAVR
Definition of intermediate risk for MI
Framingham risk score 10-20%
What coronary CTA findings suggest an increased risk for a major adverse cardiac event?
High Agatson score > 160 (means there’s a ton of calcium in the vessels)
What is the ideal heart rate for a coronary CTA?
Under 60 bpm (beta blockers should be used to achieve this if no contraindications)
Contraindications to beta blockers
- Severe asthma
- Heart block (2nd or 3rd degree)
- Acute chest pain
Can you still perform a coronary CTA if a pts HR > 60 bpm and they have contraindications to beta blockers?
Yes, but you will have to use retrospective gating (rather than the better prospective gating that can be used if HR < 60 bpm)
What are the pros and cons of prospective cardiac gating?
- Reduced radiation (because the scanner is only on during the R wave)
- Can’t do functional imaging
- More sensitive to heart rate variability
- Can’t do helical acquisitions
What are the pros and cons of retrospective cardiac gating?
- Can do functional imaging
- Less sensitive to heart rate variability
- Higher radiation (data is acquired continuously, not only during the R wave)
- Helical acquisition
What triggers imaging acquisition during a cardiac gated CT?
The R wave (if prospectively gated)
Note: If retrospectively gated, nothing triggers acquisition because images are being acquired throughout the cardiac cycle.
Which type of cardiac gating is best for valvular evaluation?
Retrospective
What medications are given for a coronary CTA?
- Beta blockers (to achieve HR < 60)
- Nitroglycerine (to maximally dilate the coronary arteries)
Contraindications to nitroglycerine
- Hypotension (SBP < 100)
- Severe aortic stenosis
- Hypertrophic obstructive cardiomyopathy
- Viagra/sildenafil/tadalafil use
What is the sequence used to look for valve stenosis/regurgitation?
Velocity-encoded cine MR imaging (a type of phase contrast imaging used to quantify the velocity of flowing blood)
What is the most common artifact with velocity-encoded MR imaging?
Aliasing, which occurs if the velocity range is too low
Note: The velocity range should be set to 20-25% higher than the maximum expected velocity. If there are still white aliasing areas, then increase the range further.
Whoa cardiac valve is the most superior?
Pulmonic
Which cardiac valve is the most anterior?
Tricuspid
If a cardiac pacing lead is seen traveling through a valve replacement, which valve is it?
Tricuspid (allowing the lead to terminate in the right ventricle)
How can you differentiate mitral from aortic valve replacements on chest radiograph?
On frontal view, draw a line from the left hilar angle to the right cardiophrenic angle (Aortic valve Above and mitral valve below)
On lateral view, draw a line from the carina to the anterior costophrenic angle (Aortic valve Above and mitral valve below)
How can you tell the direction of blood flow through a valve on chest radiograph?
The pointy parts of the valve replacement point in the direction of blood flow
How can you measure regurgitant volume of a valve on MRI?
Measure during diastole on transverse slices placed at the valve or slightly below
Why is there dilatation of the ascending aorta in aortic stenosis?
Jet phenomenon of the stenotic valve (high-velocity narrow jet through the stenotic valve)
What are the types of aortic stenosis?
- Valvular (90% of cases)
- Subvalvular
- Supravalvular
Supravalvular aortic stenosis…
Think Williams syndrome
Bicuspid aortic valve and coarctation…
Turners syndrome
What is the most common congenital heart disease?
Bicuspid aortic valve
Note: Followed by ventricular septal defects.
What is the most common complication of a bicuspid aortic valve?
Aortic stenosis
Bicuspid aortic valve is an independent risk factor for_____ (even without aortic stenosis)
Aortic aneurysm
Note: Severity of valve dysfunction does not predict aneurysm formation.
Bicuspid aortic valves are associated with…
- Cystic medial necrosis (CMN)
- Turners syndrome (and coarctation)
- Autosomal dominant polycystic kidney disease
Common causes of aortic regurgitation
- Bicuspid aortic valve
- Bacterial endocarditis
- Marfan’s syndrome
- Aortic root dilatation secondary to hypertension
- aortic dissection
Most common cause of mitral stenosis
Rheumatic heart disease
Ortner’s syndrome
Cardio-vocal hoarseness, symptomatic hoarse voice secondary to compression of the left recurrent laryngeal nerve by an enlarged left atrium
Common causes of acute mitral regurgitation
- Endocarditis
- Papillary muscle/chordal rupture s/p myocardial infarction
common causes of chronic mitral regurgitation
- Myxomatous degeneration (primary)
- dilated cardiomyopathy (secondary)
Isolated right upper lobe pulmonary edema…
Think mitral regurgitation
What are the types of pulmonary stenosis?
- Valvular (most common)
- Subvalvular
- Supravalvular
Valvular pulmonary stenosis is associated with…
Noonan syndrome
Peripheral pulmonary stenosis is seen in…
Alagille syndrome (kids with absent bile ducts)
Supravalvular pulmonary stenosis can be seen in…
Williams syndrome
What is the primary complication of tetralogy of Fallot repair?
Pulmonary regurgitation
Note: The pulmonary valve is disrupted to fix the right ventricle obstruction.
Common cause of pulmonary regurgitation
Tetralogy of Fallot repair
When should pulmonary regurgitation be fixed?
Before the right ventricle is severely dilated (after this, it won’t return to normal)
Common cause of tricuspid regurgitation
- Pulmonary arterial hypertension (most common)
- Endocarditis (IV drug use)
- Carcinoid syndrome
How does tricuspid regurgitation affect the right ventricle?
Tricuspid regurgitation causes right ventricular dilatation (NOT hypertrophy)
Pt with mitral and aortic valve disease…
Think rheumatic fever anytime there is multivalve disease (mitral and aortic valves are the most likely to be affected)
Kid with a massive “box shaped” heart on radiographs with a mom who took lithium during pregnancy…
Ebstein anomaly
Ebstein anomaly
Hypoplastic tricuspid valve with the posterior leaf displaced apically (downward), resulting in tricuspid regurgitation, right atrial enlargement, and atrialization of the right ventricle
Note: Most cases are sporadic, but there is also an association with lithium use during pregnancy.
Tricuspid atresia is associated with…
Asplenia
Note: There is also going to be an ASD or PFO.
Left-sided heart disease in a pt with carcinoid syndrome…
Think primary bronchial carcinoid (rather than GI carcinoid which would cause right-sided heart disease) OR a right-to-left shunt
What is the most common great vessel variant anatomy?
Common origin of the left common carotid and brachicephalic arteries (Bovine configuration)
What defines whether the aortic arch is right or left?
Which side of the trachea it descends on (the normal left arch has the aorta to the left of the trachea)
If you see right arch with mirror branching, think…
Congenital heart disease (mostly tetralogy of Fallot)
How can you tell right arch with mirror branching and right arch with aberrant subclavian apart?
Look at the origin of the left subclavian artery (originating from the front of the arch in mirror branching and from the back of the arch in aberrant subclavian)
What is the most common great vessel variant anatomy in pts with truncus arteriosus?
Right arch with mirror branching (33% of cases)
Is a right arch with aberrant left subclavian a vascular ring?
Yes, because the ligamentum arteriosum completes the ring on the left
What is the most common arch anomaly (not just variant anatomy)?
Left arch with aberrant right subclavian
Dilated origin of the right subclavian artery in a pt with a left arch with aberrant right subclavian artery…
Diverticulum of Kommerell
Is a left arch with aberrant right subclavian artery usually symptomatic?
No, but it can cause dysphagia lusoria (compression of the esophagus by the aberrant subclavian)
What is the most distal great vessel when there is a left arch with aberrant right subclavian?
The aberrant right subclavian
What is the most common vascular ring?
Double aortic arch
What is encircled by a vascular ring?
The esophagus and trachea
Note: Symptoms include tracheal compression and difficulty swallowing.
Subclavian steal phenomenon
Reversal of flow in the ipsilateral vertebral artery secondary to stenosis of the proximal subclavian artery
Note: This “steals” blood from the posterior cerebral circulation and can result in symptoms of cerebral ischemia, which is then known as subclavian steal syndrome.
Subclavian steal syndrome
Symptoms of cerebral ischemia in the setting of subclavian steal phenomenon
What symptoms might you expect for a pt exercising their left arm if they have left-sided subclavian steal syndrome?
- Dizziness
- Syncope
Note: In subclavian steal phenomenon, blood flow is being “stolen” from the posterior cerebral circulation.
What is the most common cause of subclavian steal phenomenon?
Atherosclerosis (98%)
Note: Other causes include Takayasu arteritis, radiation changes, preductal aortic coarctation, and Blalock-Taussig shunt.
18 y/o pt with subclavian steal phenomenon…
Think Takayasu arteritis (pt is too young for atherosclerotic disease)
Which congenital heart disease is most likely?
Transposition of the great arteries
Note: This is the “egg-on-a-string” sign.
Which congenital heart disease is most likely?
Total anomalous pulmonary venous return
Note: This is the “snowman” sign.
Which congenital heart disease is most likely?
Tetralogy of Fallot
Note: This is the “boot-shaped heart” sign.
Which congenital heart disease is most likely?
Aortic coarctation
Note: This is the “figure 3” sign, where the middle of the “3” is the coarctation.
Which congenital heart disease is most likely?
Ebstein anomaly (classically, but can also be due to non-cardiac causes of high output failure, such as infantile hemangioendothelioma or vein of Galen malformation)
Note: This is the “box-shaped heart” sign, due to massively enlarged right atrium.
Which congenital heart disease is most likely?
Scimitar syndrome (partial anomalous pulmonary venous return with pulmonary hypoplasia)
What are the major cyanotic congenital heart diseases?
5 T’s
- Tetralogy of Fallot
- Total anonymous pulmonary venous return
- Transposition of the great arteries
- Truncus arteriosus
- Tricuspid atresia
What are the major non-cyanotic congenital heart diseases?
- ASD
- VSD
- PDA
- PAPVR (partial anomylous pulmonary venous return)
- Aortic coarctation (adult type, post ductal)
Which cyanotic heart disease if right-sided arch and increased pulmonary vasculature?
Think truncus arteriosus (types 1-3)
Which cyanotic heart disease if right-sided arch and decreased/normal pulmonary vasculature?
Think tetralogy of Fallot
Which diagnoses should you think about if you see CHF in a newborn?
- Total anomylous pulmonary venous return (infracardiac, type III)
- Congenital aortic or mitral stenosis
- Left sided hypoplastic heart
- Cor triatriatum
- Infantile (pre-ductal) coarctation
Which diagnoses should you think about if you see a small heart in a newborn?
- Adrenal insufficiency (e.g. Addisons disease)
- Cachectic state
- Constrictive pericarditis
Which congenital heart diseases would result in death unless there is a coexistant shunt allowing admixture?
- Total anomylous pulmonary venous return (must have a PFO)
- Transposition of the great arteries
- Tetralogy of Fallot (must have VSD)
- Tricuspid atresia (must have VSD)
- Hypoplastic left heart
What is the most common congenital heart disease?
VSD
Note: 70% of small ones close spontaneously.
What are the types of VSD?
- Membranous, just below the aortic valve (most common)
- Outlet subtypes, infundibulum (must be repaired due to the right coronary cusp prolapsing into the defect)
When does the ductus arteriosus
close?
- Within 24 hours of birth (functionally)
- Around 1 month (anatomically)
Patent ductus arteriosus is associated with…
- Prematurity
- Maternal Rubella
- Cyanotic heart disease
What are the types of ASD?
- Ostium secundum (most common, 50-70%)
- Ostium primum, due to endocardial cushion defect
- Sinus venosus
- Coronary sinus
Which is the only type of ASD that may close without treatment?
Secundum (also the most common type)
Atrial septal defect and hand/thumb defects…
Holt Oram
Ostium primum ASD, think…
Downs syndrome
Note: Ostium primum ASD is due to an endocardial cushion defect.
Sinus venosus ASD, think…
Partial anomylous pulmonary venous return
Adults with AV septal defects have a ____% risk of recurrence of heart disease in their children
10% risk
Treatment for ostium primum ASD
surgical repair (primum ASD is not amenable to device closure due to proximity of the defect to the AV valve)
What is the most common congenital heart defect in pts with Down syndrome?
AV canal (AKA endocardial cushion defect)
Which view is best to evaluate for AV canal defects?
Four chamber horizontal long axis view
Coronary sinus ASD is associated with…
Persistent left SVC (strong association)
Complications of a coronary sinus ASD
- Paradoxical emboli
- Chronic right heart volume overload
Coronary sinus ASD
A rare form of ASD where the coronary sinus is fenestrated (or completely unroofed), allowing for left-to-right shunting
How can you tell the difference between the different types of ASD?
Location within the septum
- Ostium secundum (mid septum)
- Ostium primum (lower septum)
- Sinus venosus (upper septum, near SVC)
- Coronary sinus (fenestrated/unroofed coronary sinus, no real septal defect)
Ostium primum ASD
A spectrum of atrioventricular septal defects with the complete form including a large ventricular septal defect and a common AV valve
Note: This is also known as an AV canal defect or endocardial cushion defect.
Right-sided partial anomylous pulmonary venous return is associated with…
Sinus venosus ASD
Total anomylous pulmonary venous return requires ______ for the pt to survive
- Large PFO
- ASD (less common)
Total anomylous pulmonary venous return causes (increased/decreased) pulmonary vasculature
Increased
Note: Type 3 TAPVR is known for severe pulmonary edema.
What are the types of total anomylous pulmonary venous return?
- Type 1, supracardiac (most common)
- Type 2, cardiac
- Type 3, infracardiac with veins draining below the diaphragm (least common)
Why is type 3 total anomylous pulmonary venous return the most likely to cause frank pulmonary edema?
The pulmonary veins often become obstructed as they pass through the diaphragm
Note: Type 3 is infracardiac, with the pulmonary veins draining to either the IVC or hepatic veins below the diaphragm.
What is the most common congenital heart defect in pts with asplenia?
Total anomylous pulmonary venous return
What is the most common cause of cyanosis during the first 24 hours of life?
Transposition of the great arteries
Risk factors for transposition of the great arteries
Maternal diabetes
How can you identify transposition of the great arteries on imaging?
The aorta arises from the right ventricle (defined by the moderator band)
What are the two types of transposition of the great arteries?
- D-type (only has a PDA connecting the two systems, must be surgically corrected)
- L-type (has double discordance, leading to a congenital correction so no surgery is needed; “L”ucky to be alive)
Treatment for D-type transposition
Surgical correction with an intra-atrial baffle (Mustard or Senning procedure)
How can you differentiate D- and L-type transposition?
In D-transposition the aorta will be anterior and to the right (D for dextro) of the pulmonary artery
In L-transposition the aorta will be anterior and to the left (L for levo) of the pulmonary artery
Treatment for L-type transposition
None needed because there has been a congenital correction (the left atrium is connected to the right ventricle which is connected to the aorta, a double discordance that results in a relatively normal pathway)
Note: An L-type transposition doesn’t even need a PDA for survival.
Corrected D-transposition of the great arteries
Note: The LeCompte maneuver during surgical correction results in this characteristic appearance of the pulmonary artery being “draped” over the ascending aorta.
What is the most common cyanotic heart disease?
Tetralogy of Fallot
What are the components of Tetralogy of Fallot?
- VSD
- Right ventricular outflow tract obstruction
- Overriding aorta
- Right ventricular hypertrophy
What is the most common complication following surgical repair of tetralogy of Fallot?
Pulmonary valve regurgitation
What determines the severity of symptoms in tetralogy of Fallot?
The severity of the right ventricular outflow tract obstruction
Truncus arteriosus
Cyanotic anomaly where there is a single trunk supplying both the pulmonary and systemic circulation (no separate aorta/pulmonary artery)
Note: Almost always has an associated VSD.
Truncus arteriosus is associated with…
- VSD (almost always)
- Right-arch
- CATCH-22 genetics (DiGeorge syndrome)
What are the types of coarctation?
- Infantile (pre-ductal)
- Adult (post-ductal)
Clinical presentation of infantile coartctation
Heart failure within the first week of life and hypoplastic aortic arch
Clinical presentation of adult coarctation
Leg claudication and BP differences between arms and legs
Aortic coarctation has a strong association with…
- Bicuspid aortic valve (80% of cases)
- Turner syndrome (15-25% of cases)
Note: These pts also have increased risk of berry aneurysms.
Why does rib notching in aortic coarctation spare the 1st and 2nd ribs?
The 1st and 2nd ribs are supplied by the costocervical trunk (rather than the internal thoracic artery)
Hypoplastic left heart is associated with…
- ASD or PFO (needed for survival)
- PDA (usually large)
- Aortic coarctation
- Endocardial fibroelastosis
Cor Triatriatum Sinistrum
A rare situation where you have an abnormal pulmonary vein draining into the left atrium (sinistrum meaning left) with an unnecessary fibromuscular membrane that causes a subdivision of the left atrium, creating the appearance of a tri-atrium heart
Clinical manifestations of coronary triatriatum sinistrum
- Unexplained pulmonary hypertension in a kid
- Pulmonary edema (functionally acts like mitral stenosis)
Note: Usually fatal in 2 years depending on surgical intervention.
How does necrosis progress in myocardial infarction along the thickness of the myocardium?
Starts subendocardial and progresses to subpericardial
What does the term “microvascular obstruction” refer to when talking about myocardial infarction?
Ischemic necrosis doesn’t only the myocardium, but also the blood vessels of the myocardium, causing microvascular obstruction that prevents contrast from reaching the necrotic tissue
Stunned myocardium
Acute myocardial dysfunction in the setting of ischemia or repercussion injury that persists days/weeks after restoration of blood flow
7 days after a myocardial infarction, there is a region of the myocardium that looks normal on perfusion imaging but has poor contractility…
Myocardial stunning
Hibernating myocardium
Decreased myocardial perfusion and contractility secondary to chronic hypoperfusion in the setting of severe CAD
Imaging shows decreased myocardial perfusion and decreased contractility, even at rest but if FDG-avid on PET…
Hibernating myocardium secondary to chronic hypoperfusion in the setting of severe CAD
Note: This is reversible with revascularization.
Abnormal wall motion with decreased myocardial perfusion and photogenic on PET/CT…
Scar
Note: This is irreversible infarction.
Myocardial infarction with diastolic dysfunction should get what imaging?
Echocardiography
Myocardial infarction with systolic dysfunction should get what imaging?
Cardiac MRI
Contraindications to Cardiac MRI
- non compatible ICDs/pacemakers
- Cochlear implants
- Intracranial shrapnel
Note: Cardiac stents are usually safe.
Why does delayed imaging help identify myocardial infarctions?
- Increased volume of contrast distribution in myocardial infarction and inflammatory conditions (“bright is dead”)
- Scarred myocardium washes out more slowly
How do delayed imaging sequences work?
An inversion recovery technique is used to null normal myocardium, followed by a gradient echo. T1 shortening from the gadolinium contrast makes enhancement look bright (“bright is dead”)
Why is stress imaging does?
Coronary arteries can auto-regulate, so a stenosis of 85% can be asymptomatic at rest. Stress imaging is does so that even a 45% stenosis can be visualized.
What medications might be used for stress imaging?
- Dobutamine (inotropic stress agent)
- Adenosine (vasodilator used for perfusion analysis)
What is the characteristic pattern for acute myocardial infarction on cardiac MRI?
Delayed enhancement that extends from the subendocardium toward the epicardium in a vascular distribution. Microvascular obstruction will present as islands of dark signal in the enhanced tissue (representing an acute/subacute finding).
What does bright myocardial tissue represent on T2 sequences in the setting of an acute infarction?
Injured myocardium that is at risk but potentially salvageable
Acute vs chronic myocardial infarction on MRI
Acute infarctions should have more T2 bright signal due to edema and you may see microvascular obstruction
Chronic infarctions should be T2 dark and may have thinned myocardial tissue
How does microvascular obstruction appear on cardiac MRI?
Islands of dark tissue in an ocean of late gadolinium enhancement
Note: This is a poor prognostic sign, representing tissue that is likely not salvageable.
Microvascular obstruction is best seen on which sequence?
First pass imaging (25 seconds) delayed enhancement
Is it true that a true ventricular aneurysm usually has a mouth wider than its body?
Yes the mouth of a true ventricular aneurysm is usually wider than the body
Is the myocardium intact in a true ventricular aneurysm?
Yes, pericardial adhesions contain the rupture in a true ventricular aneurysm
What is the most common location for a true ventricular aneurysm?
The anterolateral wall
T or F: The posteriolateral wall is the most common location for a ventricular aneurysm?
False, the anterolateral wall is the most common location for a ventricular aneurysm
Note: The posterolateral wall is the most common location for a false ventricular aneurysm.
T or F: A false ventricular aneurysm increases the risk of ventricular rupture?
True, risk of rupture is increased for a false ventricular aneurysm (only pericardial adhesions contain the rupture)
For which type of ventricular aneurysm is the body larger than the mouth?
False ventricular aneurysm
Is the myocardium intact overlying a false ventricular aneurysm?
No, only pericardial adhesions contain the rupture of a false ventricular aneurysm
How can you. tell whether an area of myocardial infarction is viable or not?
Look at the % of transmural thickness involved in the infarct:
<25%: Likely to improve with PCI
25%-50%: May improve
>50%: Unlikely to recover function
When is Dressler syndrome most likely to occur following an MI?
4-6 weeks s/p MI
When is a papillary muscle rupture most likely to occur following an MI?
2-7 days s/p MI
When is a ventricular pseudoaneurysm most likely to occur following an MI?
3-7 days s/p MI
When is a ventricular aneurysm most likely to occur following an MI?
Months (requires remodeling and thinning)
When is a ventricular myocardial rupture most likely to occur following an MI?
Within 3 days of the MI (50% of the time)
Definition of dilated cardiomyopathy
Left ventricular dilatation (end diastolic diameter >55 mm) with decreased ejection fraction
What valve issue is commonly associated with dilated cardiomyopathy?
Mitral regurgitation (due to dilatation of the mitral ring)
What type of enhancement is common in ischemic cardiomyopathy?
Subendocardial enhancement
What type of enhancement is common in idiopathic dilated cardiomyopathy?
Linear mid-myocardial enhancement (or no enhancement)
Most common cause of restrictive cardiomyopathy
Amyloid
Late gadolinium enhancement over the entire subendocardial circumference…
Think amyloidosis/systemic sclerosis
MRI technician finds it “difficult to suppress the myocardium” requiring unusually long T1 (like 350 rather than the usual 200)…
Think cardiac amyloidosis
Abnormal urinary light chains (AL)…
Think amyloidosis
Bilateral ventricular thrombi…
Think eosinophilic pericarditis (Loeffler)
Note: A long T1 will be needed to show the thrombi.
How can you identify constrictive pericarditis on imaging?
- Thickened pericardium (>0.4 cm)
- Calcified pericardium (diagnostic)
If the ventricular septum moves toward the left ventricle in a wavy pattern during diastole (most pronounced during inspiration) on CINE imaging…
Think constrictive pericarditis
Note: This is the “diastolic bounce” seen in sigmoidization from constrictive pericarditis.
Most common causes of constrictive pericarditis
- Idiopathic presumed viral (most common in developed nations)
- Iatrogenic (secondary to CABG)
- Tuberculosis (most common in developing nations)
What type of delayed enhancement is common in constrictive pericarditis?
None, constrictive pericarditis is a pericardial process (not myocardial)
What type of delayed enhancement is common in myocarditis?
Mid-wall epicardial enhancement in a non-vascular distribution, preferring the lateral free wall
Common cause of myocarditis
Viral infection (e.g. Coxsackie virus)
What percentage of sarcoidosis pts have cardiac involvement?
5%
Note: This is associated with an increased risk of death.
What are the MRI characteristics of cardiac sarcoidosis
Increased T2 signal and early gadolinium enhancement. Increased late enhancement with a mid-wall/epicardial non-vascular distribution
Does cardiac sarcoidosis affect the ventricular septum?
Yes, the septum is often involved in cardiac sarcoidosis
Transient akinesia or dyskinesia of the left ventricular apex without coronary stenosis and with a ballooning of the left ventricular apex…
Takotsubo cardiomyopathy
Takotsubo cardiomyopathy
A rare form of cardiomyopathy that occurs in post menopausal women after a stressful event resulting in myocardial dyskinesia and ballooning of the left ventricular apex (making the left ventricle look like a takotsubo octopus trap)
How can you discern ischemic vs non-ischemic cardiomyopathy on cardiac MRI?
In ischemic cardiomyopathy, there will always be subendocardial delayed enhancement in a vascular distribution
In non-ischemic cardiomyopathy, the delayed enhancement is usually mid-wall/epicardial and patchy/multifocal (not conforming to a vascular distribution)
Subendocardial circumferential late enhancement…
Think amyloidosis/systemic sclerosis
Arrhythmogenic right ventricular cardiomyopathy
A genetic form of cardiomyopathy characterized by fibrofatty degeneration of the right ventricle leading to arrhythmias and sudden death
Reduced right ventricular function with fat in the right ventricular wall (signal drop out on fat sat images) and microaneurysms with normal left ventricle…
Think arrhythmogenic right ventricular cardiomyopathy (ARVC)
Note: This is characterized by fibrofatty degeneration of the right ventricle.
Asymmetric hypertrophy of the ventricular septum in a young pt with syncope…
Think hypertrophic cardiomyopathy
Hypertrophic obstructive cardiomyopathy
A subtype of hypertrophic cardiomyopathy where the anterior leaflet of the mitral valve obstructs the left ventricular outflow tract due to systolic anterior motion (SAM) of the mitral valve
What type of delayed enhancement is common in hypertrophic obstructive cardiomyopathy?
Patchy midwall delayed enhancement of the hypertrophied ventricular septum
Left ventricular noncompaction
A rare congenital cardiomyopathy that is the result of loosely packed myocardium, creating a spongy appearance with increased trabeculations and deep intertrabecular recesses, resulting in heart failure at an early age
Prominent ventricular trabeculation in a young pt with early onset heart failure…
Think left ventricular noncompaction
What are the two types of muscular dystrophy?
- Becker (mild)
- Duchenne (severe)
What type of genetic disorders are Becker and Duchenne muscular dystophy
Both are X-linked neuromuscular conditions (almost only seen in males)
Kid with a dilated heart demonstrating mid-wall delayed enhancement…
Muscular dystrophy (Becker or Duchenne depending on severity)
What is the most common type of cardiac tumor?
Metastases (30x more common than primary cardiac tumors)
What is the most common site of a cardiac tumor?
Pericardium (most often metastatic disease)
What is the most common clinical manifestation of a cardiac tumor?
Pericardial effusion
Note: Second most common is a pericardial lymph node.
Which type of cancer can metastasize to the myocardium (rather than the usual pericardium)?
Melanoma
What is the most common met to the heart?
Lung cancer (found in the pericardium and epicardium)
Note: Melanoma more commonly metastasizes to the heart, but lung cancer is much more common in general.
Which type of cancer has the highest percentage of cases with metastases to the heart?
Melanoma
What is the most common primary malignant tumor of the heart in adults?
Angiosarcoma
Cardiac angiosarcoma
A bulky and heterogeneous cardiac tumor that preferentially involved the pericardium of the right atrium, often with a “sun-ray” appearance of enhancement as it grows along perivascular spaces associated with the epicardial vessels
What is the most common location for a cardiac angiosarcoma?
Right atrium pericardium
Adult with “sun-ray” enhancment of a pericardial tumor growing along epicardial vessels centered at the right atrium…
Think angiosarcoma
Most common primary cardiac tumor in adults
Left atrial myxoma
Left atrial myxomas are associated with…
- MEN syndromes
- Blue nevi (Carney Complex)
How can you differentiate a left atrial myxoma from a thrombus?
Only a left atrial myxoma will enhance on cardiac MRI
What is the most common location for a left atrial myxoma?
Left atrium, attached to the interatrial septum
What is the most common fetal cardiac tumor?
Rhabdomyoma
Note: This is a type of hamartoma. Second most common cardiac tumor in childhood is fibroma.
What is the most common location for a cardiac rhabdomyoma?
Left ventricle
Cardiac rhabdomyomas are associated with…
Tuberous sclerosis
Note: Cardiac rhabdomyomas associated with tuberous sclerosis are less likely to regress spontaneously.
Prognosis for cardiac rhabdomyomas
Most regress spontaneously
Note: These are a type of hamartoma. Those associated with tuberous sclerosis are less likely to spontaneously regress.
What is the most common location for a cardiac fibroma?
The interventricular septum
How can you identify a cardiac fibroma?
Hypointense on T1 and T2 with vivid enhancement
Interventricular septal mass that is dark on T1 and T2 with bright enhancement…
Cardiac fibroma
What is the most common neoplasm to affect the cardiac valves?
Fibroelastoma
What is the most common location for a cardiac fibroelastoma?
Aortic or mitral valves (80%)
Note: Aortic valve is most common.
Common complication of cardiac fibroelastoma
Systemic emboli
Note: Fibroelastomas usually affect cardiac valves and are highly mobile on cine imaging and often throw tumor emboli.
What is the most common intra-cardiac mass?
Thrombus
Clinical manifestation of cardiac fibroelastoma
Usually stroke/TIA from systemic tumor emboli (otherwise mostly an incidental finding)
How can you differentiate valve vegitations from a cardiac fibroelastoma?
Vegitations tend to involve the valve free edges, which fibroelastomas do not involve
Infant with tuberous sclerosis and a tumor involving the myocardium…
Rhabdomyoma
Note: Should be T2 bright (if it is T2 dark consider fibroma, which is also common in this age group).
Adult with a large heterogeneous cardiac mass with pericardial thickening…
Think angiosarcoma
Note: The pericardial thickening suggests invasion.
Pericardial nodularity and pericardial effusion in an older pt…
Think pericardial metastases
What are common locations for an intracardiac thrombus?
- Left atrial appendage (most common)
- Left ventricular apex (common following MI)
What is the normal amount of pericardial fluid?
50cc
Note: More than this is considered a pericardial effusion.
What is the most common cause of pericardial effusion?
Renal failure (uremia)
Note: Also think about systemic lupus erythematous and post MI Dressler syndrome for MCQs.
30 y/o female with a facial rash and new cardiomegaly (was normal 1 month prior)…
Think systemic lupus erythematosus
New cardiomegaly in a pt with an MI 1 month prior…
Think Dressler syndrome (cardiomegaly due to pericardial effusion)
How does a pericardial effusion appear on radiography?
- Rapid onset cardiomegaly (was recently normal)
- Giant water flask-shaped heart
- Lateral radiograph with oreo cookie sign
Oreo cookie sign of pericardial effusion
On lateral radiograph, two Lucent lines (representing epicardial and pericardial fat) with a central opaque line (pericardial fluid)
How much pericardial fluid can cause cardiac tamponade?
As little as 100 cc (normal is 50 cc), if it accumulates rapidly without enough time for compensation.
Pericardial effusion with flattening/inversion of the interventricular septum towards the left ventricle during inspiration…
Cardiac tamponade
Water-density cyst along the right cardiophrenic sulcus…
Pericardial cyst (benign)
What is the most common location for a partial absence of the pericardium?
Absent pericardium over the left atrium and adjacent pulmonary artery
If you are shown a CT/MRI with the heart contacting the left chest wall, but otherwise normal…
Think partial absence of the pericardium
Note: The most common location for partial absence of the pericardium is the left atrium, allowing loftward shifting of the heart.
What is a possible complication s/p extrapelural pneumonectomy in pts with partial absence of the pericardium?
Cardiac herniation +/- volvulus
Note: This can only happen if there is lung removed AND partial absence of the pericardium.
Which portion of the heart is most at risk for strangulation in pts with partial absence of the pericardium?
Left atrial appendage
If you see pulmonary parenchyma between the aorta and the pulmonary artery…
Think partial absence of the pericardium
Treatment for hypoplastic left heart
Palliative surgery in 3 stages (no cure)
- Norwood or Sano (within days of birth)
- Glenn (at 3-6 months)
- Fontan (at 1.5-5 years)
Note: This is done to protect the lungs and avoid right heart overload.
Norwood surgery
Surgical creation of an unobstructed outflow tract from the systemic ventricle in pts with a hypoplastic left heart
Note: This is the first of 3 surgeries for hypoplastic left heart.
How is an unobstructed ventricular outflow tract created during the Norwood surgery for hypoplastic left heart?
The small native aorta is anastomosed to the pulmonary trunk and the arch is augmented with a graft. The ASD is enlarged to create nonrestrictive atrial flow.
What is the difference between the Norwood and Sano procedures for hypoplastic left heart?
The Norwood uses a Blalock-Taussig shunt between the right subclavian and right pulmonary artery
The Sano uses a conduit made to connect the right ventricle to the pulmonary artery (avoiding the steal phenomenon that occurs with the Blalock-Taussig shunt due to low pressure pulmonary system)
What is the most common cause of failure following a Norwood procedure for hypoplastic left heart?
- Damage to coronary arteries
- Over shunting of blood to the lungs, causing pulmonary edema
Note: The ductus arteriosus is usually removed to help prevent over shunting to the lungs.
What is the benefit of a conduit between the right ventricle and pulmonary artery (used in the Sano procedure) over a Blalock-Taussig shunt between the right subclavian and right pulmonary artery?
Less steal phenomenon (for the BT shunt, blood is diverted to the low pressure pulmonary system)
Classic Glenn procedure
Shunt formation between the SVC and right pulmonary artery (end-to-end) and the additional step of sewing the proximal end of the right pulmonary artery closed (with the goal of reducing right ventricular work by diverting all venous return to the right lung)
Bi-directional Glenn procedure
Shunt formation between the SVC and right pulmonary artery (end-to-side) with the right pulmonary artery left open (letting blood flow to both lungs, unlike in the classic Glenn)
Note: If for hypoplastic left heart, the BT shunt or Sano shunt will be taken down.
Fontan operation
- SVC to right pulmonary artery shunt (classic Glenn)
- Closure of ASD
- Shunt between right atrium and left pulmonary artery
Note: This allows passive blood return from systemic circulation and turns the right ventricle (the only functional one) into a functional left ventricle.
plications of Fontan operation
- Right atriomegaly (with resultant arrhythmias)
- Plastic bronchitis (pts cough up “casts of the bronchus” that look plastic)
What are indications for Bi-directional Glenn?
- HYpoplastic left heart (second stage)
- Can be used to address general right-sided heart problems
Classic Blalock-Taussig shunt
Shunt creation between the subclavian artery and the pulmonary artery (performed on the opposite side as the aortic arch)
Note: This is an artery-to-artery shunt.
What shunt is created during a classic Glenn or Bi-directional Glenn?
Shunt between the SVC and the right pulmonary artery (end-to-end in classic Glenn and end-to-side in bi-directional Glenn)
Note: This is a vein-to-artery shunt.
Modified Blalock-Taussig shunt
A cortex shunt between the subclavian artery and pulmonary artery (performed on the same side as the aortic arch)
Note: This is technically easier than the classic BT shunt that is performed on the side opposite the aortic arch.
Indications for pulmonary artery banding
CHF in infancy with anticipated delayed repair (most commonly when there is a single ventricle)
What is the goal of pulmonary artery banding?
Reducing pulmonary artery pressure (goal is 1/3 systemic pressure)
What are the two atrial switch procedures?
Senning (baffle is created from the right atrial wall without the use of extrinsic material)
Mustard (atrial septum is resected and a paffle is created using pericardium or a synthetic material)
Rastelli operation
Placement of a baffle within the right ventricle diverting flow from the VSD to the aorta (essentailly making the VSD part of the left ventricular outflow tract), allowing the left ventricle to become the systemic ventricle
Indications for the Rastelli operation
- Transposition of the great vessels
- Pulmonary outflow obstruction
- VSD
What is the primary limitation of the Rastelli operation?
The child will be committed to additional surgeries because the conduit wears out and must be replaced
Jatene procedure
An arterial switch method that involves transection of the aorta and pulmonary arteries about the valve sinuses (including removal of the coronaries). The great arteries are then switched and the coronaries are sewn into the new aorta (which was previously the pulmonary artery)
What is the downside to the Jatene procedure?
It is technically difficult
Note: Though difficult, this avoids having to perform repeat procedures to replace the conduit of the Rastelli operation.
Ross procedure
Replaces the aortic valve with the patients pulmonary valve and replaces the pulmonary valve with a cryopreserved pulmonary valve homograft
Indications for the Ross procedure
Diseased aortic valves in children (the Ross procedure replaces the aortic valve with the pts pulmonary valve)
Bentall procedure
Operation involving composite graft replacement of the aortic valve, aortic root, and ascending aorta, with re-implantation of the coronary arteries into the graft
Note: This is used to treat combined aortic valve and ascending aorta disease (including in Marfan’s).
Indications for the Bentall procedure
Combined aortic valve and ascending aorta disease (including lesions associated with Marfan’s syndrome)
What is the primary purpose of the Glenn procedure?
Take systemic blood directly to the pulmonary circulation (bypassing the right heart)
Note: This is achieved with an SVC to pulmonary artery shunt (vein to artery).
What is the primary purpose of a Blalock-Taussig shunt?
Increase pulmonary blood flow
Note: This is achieved with a subclavian artery to pulmonary artery shunt (artery to artery).
What is the primary purpose of the Fontan procedure?
Bypass the right ventricle and direct systemic venous return into the pulmonary arteries
Note: Procedure steps are complicated and varied and unlikely to be tested.
Most testable complications of the Glenn procedures
- SVC syndrome
- Pulmonary artery aneurysms
Most testable complications of a Blalock-Taussig shunt
Stenosis at the shunts pulmonary insertion site
Most testable complications of the Fontan procedure
- Enlarged right atrium causing arrhythmias
- Plastic bronchitis (coughing up plastic-looking casts of bronchi)
Orthotopic heart transplant
All of the heart is removed except the circular part of the left atrium that connects to the pulmonary veins. The donor heart is trimmed to fir the left atrium.
heterotopic heart transplant
The recipients heart remains in place and the donor heart is added on top, creating a double heart
Note: This gives the native heart a chance to recover and gives a backup in case the donor heart is rejected.
