Coronary artery anomalies and disease Flashcards
Coronary arteries arise from 3 anatomic outpouchings called
Sinuses of valsalva
True or false: no coronary artery should arise from the noncoronary sinus, which is directed posteriorly toward the interatrial septum
True
Largest coronary artery
Left main coronary artery
In approximately 20 to 30% of patients, the left main coronary artery trifurcates with what branch, in between the LAD and LCx
Ramus intermedius
Large vessel that runs along the anterior surface of the left ventricle
Left anterior descending artery
Gives rise to both septal branches and diagonal coronary artery branches
Left anterior descending artery
Supplies oxygenated blood to anterolateral and anteroseptal LV myocardium
Diagonal and septal branches of LAD
Supply oxygenated blood to the inferolateral aspect of LV
Obtuse marginal vessels from LCx
Gives rise to posterior descending artery and posterior left ventricular branches
Right coronary artery
Defined as the ostium of RCA to 1/2 the distance to the acute margin of heart
Proximal RCA
Defined as the end of the proximal RCA to the acute margin of the heart
Mid RCA
Defined as the end of the mid RCA to the origin of PDA
Distal RCA
Vessel that courses in the posterkor interventricular sulcus to supply the inferior wall of LV
Posterior descending artery
Usually the first branch of RCA; it supply blood to the right ventricular outflow tract or conus
Conus branch
Sometimes acts as a collateral pathway for blood flow to the LAD and this circuit is often referred to as the arterial circle of Vieussens
Conus branch
Small vessel that most often originates from RCA, but arises from LCx in about 1/3 of patients
Sinoatrial nodal branch
SA nodal branch courses posteriorly, if its from what artery
RCA
SA node courses medially if its from
LCx
SA node is located where
Posterior aspect of where the SVC enters the RA
In most patients, AV nodal branch arises from
Very distal “U-shaped” aspect of the distal RCA as it courses superior to PDA
Small vessel that courses superiorly toward the posterior annulus of mitral valve
AV nodal branch
Benign variant of left main coronary artery in which LAD and LCx have independent origins from the left sinus of Valsalva
Absence of the left main coronary artery
High origin of a coronary artery occurs when its ostium is located __ cm or greater above the sinotubular junction
1 cm
Anomalous origin of coronary arteries outside of aortic root most commonly affects what artery
RCA
Retroaortic course of coronary artery arises from the opposite sinus and courses posteriorly between the aorta and left atrium. It most commonly occurs in
LCx or left main coronary artery that arises from right sinus of valsalva
Occurs when an anomalous coronary artery courses anterior to RVOT
Prepulmonic course
Prepulmonic vessel often arises directly from _______ in the setting of a single coronary artery
Proximal RCA
Septal course of coronary artery usually involves what artery
Left anterior descending artery
Origin from the noncoronary sinus is an extremely rare anomaly that can occur with
RCA or LCA
Course of coronary artery where it arises from the opposite sinus and courses medially between the aorta and pulmonary artery
Interarterial course
Interarterial course of coronary artery, especially if this artery is involved, can lead to myocardial ischemia, infarction and sudden cardiac death
Left main or LAD
In interarterial course of RCA, a higher incidence of symptoms and adverse cardiac events has bern reported in those with a
More superior course of the interarterial vessel (between the aprta and pulmonary artery) as compared to those with a more inferior course (between the aorta and rvot)
A rare congenital anomaly wherein there anomalous origin of the left main coronary artery from the pulmonary artery
Bland-Garland-White syndrome
Single coronary artery is common in what side
Right
Ostial atresia is more common on what side
Left main coronary artery ostium
This anomaly us often associated with sudden cardiac death in newborns but patients can survive into adulthood if collateral pathways between the opposite coronary circulation exist
Ostial atresia
True or false: in ostial atresia, just distal to the atretic segment is a normal coronary anatomy
True
Common incidental finding and has been reported in up to 58% of patients undergoing coronary CTA and in up to 86% of autopsies
Intramyocardial course of a coronary artery/ myocardial bridging
Bridging most often involves the ____ where a band of myocardial tissue extends around the vessel
Mid-LAD
in myocardial bridging, patient may be asymptomatic because
even tho the vessel is compressed during systole, the arteries fill during diastole
altho myocardial bridging can be asymptomatic, angina and ischemia can occur through what various mechanisms
phasic systolic vessel compression, persistent diastolic lumen diameter reduction, increased blood flow velocities, retrograde systolic flow and reduced coronary flow reserve
there is increased incidence of coronary artery atherosclerotic disease at what part or segment of the myocardial bridged segment
proximal to the bridge; the bridged segment is typically free of disease
intracavitary course of coronary artery usually involves what artery
RCA extending into the RA
in most instances, a split or double coronary artery presents as
one coronary artery arising from the sinus of Valsalva, which then divides in its proximal portion into two parallel coronary arteries that mirror their courses
Coronary fistula are most often
Congenital
Drainage in coronary fistula is most commonly on what side
Right side (coronary sinus to pulmonary artery) physiologically acts like a left to right shunt
In coronary fistula, patients often present with
Congestive heart failure due to long standing shunt, ischemia due to a steal phenomenon (preferential flow of blood thru lower-pressure fistula instead of through higher-pressure capillary bed), or endocarditis
Leading cause of mortality of both men and women in the western world
Coronary artery disease
One of the main uses of coronary cta is
In patients with nonacute chest pain and a low to intermediate pretest probability of having severe obstructive coronary disease
True or false: coronary cta should not be performed in patients having acute coronary syndrome with ST elevation or elevated troponin level so
True
Currently, coronary artery calcification scoring is performed using
Prospective ECG gating with data reconstructed at a 2.5 mm slice thickness
Tube potential recommended for CACS
120 kV
Calcifications related to atherosclerotic disease
Intimal calcifications
Calcifications that occur due to an osteoblastic-like factor released from intimal vascular smooth muscle cells
Intimal calcifications
Refers to outward growth or expansion of both the coronary artery and associated plaque. It is primarily caused by medial and adventitial inflammation which weakens the underlying framework of the coronary artery and causes its outward expansion
Positive remodeling complex
Inward growth of calcification, causing stenosis
Negative remodeling
True or false: positive and negative remodeling usually occur together
True
Caused by medial and adventitial inflammation which weakens the underlying framework of the coronary artery and causes its outward expansion
Positive remodeling
Low attenuation plaque is defined as a plaque with attenuation value of ____, corresponds to a plaque with a larger lipid-rich necrotic core and thus has a higher propensity to rupture
<30 HU
An additional coronary CTA Finding that may be indicative of a thin-cap atheromatous vulnerable plaque is termed the
Napkin ring sign
A rim of high attenuation surrounding an area of low attenuation representing the inflamed fibrous cap surrounding the necrotic lipid core, and its presence can be an independent predictor of a future acute coronary event
Napkin ring sign
In the left main coronary artery, a stenosis of ____ % is considered severe
> 50%
Coronary stenosis is classified as absent, minimal, mild, moderate, severe and occlusive by how many %?
Absent 0% Minimal 1-24 % Mild 25-49% Moderate 50-69% Severe 70-99% Occlussive 100%
In myocardial perfusion CT, images of the heart and coronary arteries are obtained during ____, when the iodinated contrast is predominantly intravascular
Early portion of first-pass circulation
In myocardial perfusion imaging, infarcted tissue should show
Persistent perfusion defecrs during rest imaging
In myocardial perfusion ct, iodinated contrast will concentrate in infarcted tissue and can be visualized by obtaininh a third scan _____ minutes after the last contrast administration
5-10 minutes
It is derived from invasive coronary angiography where the differences in pressure across a stenosis are directly measured
CTa derived fractional flow reserve testing
An FFR measurement of 1 means
No change in pressure across a stenosis
FFR of 0.7 means
Pressure distal to the stenosis is only 70% of that proximal to the stenosis
In general,FFR of 0.8 or lower is considered
Hemodynamically significant
In patients with acute chest pain and ECG changes or elevated cardiac troponin levels, the first line of therapy is
Thrombolysis and revascularization
This is an excellent tool to assess patients presenting to the ED with acute chest pain, a low to intermediate risk of CAD, and a negative troponin level
Coronary CTA
Primary noninvasive technique for evaluatinh the coronary arteries
Coronary CTA
True or false: coronary MRA can be done without contrast
True
Coronary MRA is accepted as a tool to assess
for anomalous coronary arteries and coronary artery aneurysms, especially in the pediatric population, or those with severe contrasr allergies
At 1.5 T,cMRA is performed using a whole heart, free-breathing, _____ sequence
3D steady-state free precession (SSFP)
True or false: in cMRA using 3T, gadolinium contrast agents are recommended due to the different sequences used
True
Gold standard for evaluating cardiac function and can differentiate between ischemic and nonischemic etiologies of myocardial injury and dysfunction
MRI
When a patient undergoes a cardiac MRI with a known or suspected ischemic cardiomyopathy, the radiologist has four main goals, namely
Confirm or refute the suspected diagnosis, evaluate cardiac function and morphology, assess for myocardial viability and look for any complications
Functional cardiac evaluation in 3T MRI uses what sequences
GRE or SSFP
To acquire a single slice along a prespecified cardiac plane, what technique is done
Expiratory breath-held, retrospectively gated, segmented sequence is obtained over multiple heart beats
Mainstay slide thickness and gap used in cardiac MRI
6-8 mm slice thickness, sometimes with a 2mm gap between slices, a short axis stack of cine SSFP or GRE, throigh the entire cardiac axis from the mitral valve plane to cardiac apex
Cardiac wall motion can be described as
Hypokinetic (reduced contractility), akinetic (no contractility) or dyskinetic (paradoxical movement)
Anterior and anteroseptal segments at the base and mid cavity levels are supplied by
LAD and its branches
Anteroseptal segments can be supplied by
Diagonal branches from LAD
Often supplies the inferolateral segment but can also supply portions of the anterolateral and/or inferior segments depending on size and dominance
LCx and OM
At the apical level, in many patients, the anterior, lateral and septal segments are supplied by
LAD distribution
Inferior segment is supplied by the
PDA
The cardiac apex (segment 17)is usually supplied by
LAD
In the setting of recent MI, there may be increased subendocardial signal intensity at what sequence, due to edema
T2
The T2 Sequences in recent MI are usually performed using
Doube inversiom recovery “black blood”, or triple inversion recovery to null both blood and fat
As the myocardium remodels after an infarct, the affected segments can become _____. This is often associated with worsening function as the affected segments may become akinetic or dyskinetic
Thinned
True or false: while myocardial thinning often suggests scarring, it does not necessarily indicate nonviable myocardium, which is assessed using delayed enhancement imaging
True
Contrast enhanced cardiac mri shows enhancement or nonenhancement in areas where there has been acute myocyte injury or subacute infarct
Enhancement, secondary to cell membrane disruption, causing pooling of contrast
Aside from gadolinium enhancement of acute or subacute myocardial infarct, chronic infarcts can also show enhancement due to its accumulation in the interstitial space due to scarring. Therefore, these sequence techniques are done to differentiate regions affected
Inversion time (double or triple)
A myocardial injury from an infarct starts in the
Subendocardial region of the ventricle and extends outward
Subendocardial enhancement measuring ____ of the regional myocardial thickness is associated with functional recovery after revascularization
<50%
If the infarct involves the entire thickness of the myocardium, it is called
Transmural infarct
Large transmural infarcts, especially those in LAD distribution are more likely to cause
Left ventricular aneurysms
Due to alterations of blood flow, anterior left ventricular aneuryms have a propensity to develop _____ which can subsequentlu embolize
Thrombus
Specific form of myocardial reperfusion injuru that occurs after therapy for an acute MI
Microvascular obstruction
Microvascular obstruction occurs when after reperfusion, and when can it increase in size after injury
Nearly immediately after reperfusion, can increase in size up to 48 hours after injury, and can be seen up to 1 month after reperfusion
True or false: gadolinium cannot diffuse into areas of microvascular obstruction
True
On LGE imaging, microvascular obstruction appears as
Dark, nonenhanced areas surrounded by enhancing infarct
When present, it is an indicator of severe myocardial injury that often leads to adverse left ventricular remodeling and is an independent predictor of worse patient outcomes
Microvascular obstruction
Imaging that can be used to distinguish ischemia from prior myocardial infarction
Stress MR imaging using SSFP and perfusion imaging
Rest followed by stress MR imaging is often performed using pharmacologic agents such as ______ because of the challenges of introducing MR compatible equipment into the MR imaging suite to perform physiologic stress testing
Adenosine
Stents ___ mm in diameter are more likely to be evaluable
> |= to 3 mm
Definitive treatment for advanced CAD
Coronary artery bypass grafting
Artery that has a patency pf 85% after 10 years
Internal mammary
Commonly used side of internal mamary artery for grafting
Left; due to its proximity to the lefr ventricular apex
When a saphenous vein graft thrombose, all that may be visivle is a small, vascular outpouching from the ascending aorta, a finding that is sometimes referred to as the
Nubbin sign
Aneurysms froM SVG graft occurs commonly at what distibution side
RCA distribution grafts
In contrast to SVGAs, which occurs after 5 to 10 years after, pseudoaneurysms can occur when
First weeks to months after surgery, due to graft breakdown and dehiscence
Defined as segment of the coronary artery that measures more than 1.5 times the adjacent normal coronary artery
Coronary artery aneurysm
Most common cause of coronary artery aneurysm in pediatric population is
kawasaki disease; systemic small and medium vessel vasculitis
True or false: smaller coronary attery aneurysms may decrease in size or resolve in patients with kawasaki disease
True
Most common cause of coronary artery dissection
Percutaneous interventions
Type of aortic dissection involving the ascending aorta and can extend into the aortic root
Type A
Cause of coronary artery dissection in young women and was the cause of MI in 24% of women less than 50 y.o udergoing cadiac catheterization
Spontaneous coronary artery dissection
3 catastrophic mechanical complications after acute myocardial infarction
Left ventricular free wall rupture, ventricular septal rupture, papillary muscle rupture
Occurs when there is a tear thru the myocardium which is contained by adjacent pericardium or scar tissue
Left ventricular aneuryms aka left ventricular free wall rupture
Most cardiac pseudoaneurysms invole the
Inferior and inferolateral walls
In general, true cardiac aneurysms have
Broad neck
Septal rupture can develop after transmural infract and leads to
Left to right shunt
Papillary muscle that is 6 to 13 times more likely to rupture after MI
Posteromedial papullar muscle of LV
Posteromedial papillary muscle is supplied by
PDA
