Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Medical > CT - Chapter 8 > Flashcards

CT - Chapter 8 Flashcards

You may prefer our related Brainscape-certified flashcards:
USMLE® Step 1 flashcards
1
Q

How can a myocardial perfusion defect be differentiated from an artifact?

A
  • True perfusion defect will:
    • persist throughout multiple, different phases of the cardiac cycle
    • visualized in both systole and diastole
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Which are the best window width and window level for assessing myocardial perfusion defects, respectively?

A

WW: 200 / WL: 100

  • subtle differences need to be displayed
  • narrow window width and window level similar to the normal myocardial attenuation will improve visualization o f perfusion defects as compared to normal myocardium
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Which coronary artery distribution is affected by the perfusion defect displayed in the image?

A

LCx or RCA (depending on dominance)

  • perfusion defect involving the inferior, inferoseptal and inferolateral walls
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Describe the finding:

A

Microvascular obstruction

  • CT findings:
    • delayed enhancement CT image (10 minutes after contrast injection)
    • apparent due to hyperenhancement of parts of the otherwise dark myocardium
    • Previous MI
      • surrounding delayed hyperenhacement –> myocardial necrosis
      • inner dark area + outer bright area –> total infarct size
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What are the characteristics of chronic infarct by cardiac CT?

A
  • LV wall thinning
  • Myocardial calcification
  • LV remodeling
  • LV dilatation
  • Lower CT attenuation (due to fatty infiltration)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is not a typical imaging finding in infective endocarditis?

A

Valvular stenosis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What are commonly observed findings on cardiac CT in assessment of severe AS?

A
  • Aortic root aneurysm with ST junction effacement
    • more common with BAV
  • Concentric LVH
  • Left atrial dilatation
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Describe the findings

A

Congenitally BAV

  • CT findings:
    • linear closure of left and right coronary cusp during end-diastole without so much as a raphe to suggest prior separation of these leaflets with calcificaiton
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Describe the findings

A

Myxomatous disease of the mitral valve

  • CT findings:
    • 2-chamber view shows “billowing” of mitral leaflets past the annulus plane towards the LA during ventricular systole with associated thickened leaflets
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What are the best views to confirm mitral valve prolapse on cardiac CT?

A

3-chamber view or PLAX view

  • 2-chamber and 4-chamber views tend to overestimate the prolapse
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

When performing CCTA on patients with severe AS, what medications should be avoided / or used with caution?

A

BB and Nitrates

  • AS patients have a fixed LVOTO and are unable to augment CO much to compensate for hypotension (from either BB or Nitrates)
  • any augmentation in CO, occurs predominatly through increased HR, which is blunted with BB due to scanning
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Which phase (in %) of the R-R interval should be selected for CT image reconstruction to perform planimetric measuremet of the aortic valve orifice area (AVA) in AS evaluation?

A

10-20%

  • CT images should be reconstructed during mid-systole, using retrospective ECG-gating –>
  • phase of maximal and stabilized aortic valve opening
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Which plane (view) should be used for evaluation of aortic valve morphology?

A

SAX of the LVOTO

  • Axial images –> give an oblique view of the AV and are not appropriate to use
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Describe CT technique for mitral regurgitation

A
  • Only seen during systole (5-25% of R-R interval)
  • Appropriate:
    • Prospective and Retrospective
    • ECG-gating
    • 100 kVp
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Describe the findings

  • Image reconstruction at 70% R-R interval
A

ASD + PV stenosis

  • ASD
    • L-to-R shunting of blood
    • located in the fossa ovalis
    • likely secondary to small secundum ASD or stretched PFO
  • PV stenosis
    • stenosis of the left lower pulmonary vein at the left atrial insertion
  • Papillary muscle
    • normal in size
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is a common association with sinus venosus ASD?

A

PAPVR (partial anomalous pulmonary venous return)

  • Inferior sinus venosus ASD
    • IVC - RA communication
    • RIPV (right inferior pulmonary vein) PAPVR
  • Superior sinus venosus ASD
    • SVC - RA communication
    • RUPV (right upper pulmonary vein) PAPVR
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What is a common associated finding with persistent left SVC?

A

Primum or Secundum ASD

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Describe the findings

A

Persistent L SVC

  • CT findings:
    • contrast-filled structure betwee the LAA and the L superior pulmonary vein
  • Asymptomatic, finding
  • Clinical importance (R sided placement):
    • PPM or ICD
    • Central venous catheter
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Describe the findings

A

Unroofed coronary sinus (CS) –> enlarged RA, RV, dilated coronary sinus

  • left-to-right shunt and RV volume overload
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What is the most common course of the esophagus in the posterior mediastinum?

A

Paramedian left - (88-93%)

  • Paramedian right - (12%)
  • important consideration to avoid complications such as atrial-esophageal fistula in the context of atrial ablation procedures
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What contrast injection protocol should be used for Ct of the cardiac veins?

  • planning for biventricular PPM implantation
A

Delayed arterial phase

  • +/- 5-10 seconds after peak of ascending aorta or the coronary arteries
22
Q

Where is the Thebesian valve located?

A

Orifice of the coronary sinus

  • semicircular fold at the orifice of the coronary sinus
  • visualized in 33% of cases
23
Q

Where is the Vieussens valve located?

A

located in the great cardiac vein near the beginning of the coronary sinus

  • serves as an anatomic landmark
24
Q

Where is the Eustachian valve located?

A

RA

  • endocardial fold that arises from:
    • anterior margin of the IVC –>
    • anterior part of the limbus fossa ovalis
25
Q

Describe the findings

A

PFO - contrast between the septum primum and the septum secundum

  • if there is contrast passing through the interatrial septum into the RA –> PFO
26
Q

What is the lower limit cutoff for a normal LVEF by cardiac CT?

A

> 55%

27
Q

What is the lower limit cutoff for a normal RVEF?

A

48%

28
Q

What is the normal interventricular basal septal thickness at end-diastole?

A

9-11 mm

  • all measurements taken at end-diastole
29
Q

What is the normal thickness of the apical thin point?

A

1-3 mm (in width)

  • short segment at the apex of the LV, where all fibers converge to a thin fibrosis point
30
Q

What is the normal thickness of the mid-chamber LV walls in end-diastole?

A

6-11 mm

31
Q

What is the normal LA volume immediately before mitral valve opening?

A

57-105 mL

32
Q

What is the normal RA volume immediately before opening of the TV?

A

75-115 mL

33
Q

Describe the findings/diagnosis

A

Myxoma

  • 25-50% of all primary cardiac tumors
  • size: 1-15 cm
  • Most common locations:
    • LA 60-75%
    • RA 20-28%
34
Q

Describe the findings:

A

Lipoma

  • 8-12% of primary cardiac tumors
  • encapsulated, contain neoplastic fat cells and occur at young ages
35
Q

What is the most likely diagnosis of the appearance of the interatrial septum?

A

Lipomatous hypertrophy of the interatrial septum (LHIS)

  • bilobed, “dumbbell-shaped” fatty mass must be:
    • > 20 mm in thickness and
    • spare the foramen ovale
  • often found in older and overweight patients
  • unlike lipomas, they are uncapsulated and contain lipoblasts and mature fat cells
36
Q

Describe the findings

A

Papillary fibroelastoma (on anterior MV leaflet)

  • 2-33% of primary benign cardiac tumors
  • 80% found on AV or MV leaflets
37
Q

Describe the findings and differential diagnosis:

A

Angiosarcoma (biopsy proven)

  • CT findings:
    • ​RA mass​
    • irregular and lobulated contours –> suggesting malignancy
    • density –> not suggestive of fat content
  • Differetial:
    • Angiosarcoma
    • Metastases
    • Cardiac Lymphoma
38
Q

Describe the findings

A

Cardiac Sarcoma (poorly differentiated)

  • 24% of primary cardiac malignancies
  • most undifferentiated sarcomas are found in the LA
  • Common findings:
    • discrete mass
    • irregular contours
    • infiltrative
    • necrosis and hemorrhage
39
Q

What is the origin of the carcinoma invading the heart?

A

Lung

  • most common metastases to the heart and pericardium are from lung cancer
  • CT findings:
    • bilateral, calcified pleural plaques –> asbestos exposure
40
Q

What are common primary tumors that metastasize to the heart?

A
  • Lung
  • Breast
  • Renal
  • Lymphoma/Leukemia
  • Esophageal
  • Melanoma
41
Q

What are the ways which cardiac metastases occurs?

A
  • Direct invasion
  • Lymphatic extension
  • Hematogenous spread
  • Transvenous extension

*****malignant pericardial effusion is the most common manifestation of metastasis

******Likely from lymphatic extension or direct invasion

42
Q

Describe the findings

A

Interatrial septal aneurysm + LHIS

  • > 10-15 mm to either chamber size
43
Q

Describe the findings

A

Angiosarcoma / Malignant pericardial effusion

  • malignant involvement of the pericardium may be primary (less common) or secondary to spread from a nearby or distant focus/malignancy
44
Q

Describe the findings

A

PFO​

45
Q

Describe the findings and chamber involved

A

LA - incomplete septation of LA / Cor triatriatum sinister

  • congenital anomaly in which the left or right atrium is divided into two parts by a fold of tissue, a membrane, or a fibromuscular band
46
Q

Describe the findings

A

SVC syndrome

  • mass invading much of the heart, including the LA
  • CT findings:
    • injected contrast flows through the azygous vein rather than the SVC –>
    • indicating that the SVC is at least partially obstructed at some level
47
Q

Describe the findings

A

Tetralogy of Fallot

  • CT findings:
    • Left pain
      • right-sided aortic arch
      • present in 25% of cases
    • Middle pain
      • severe hypoplasia of the pulmonary infundibulum
      • subvalvular or valvular RVOT stenosis
    • Right pain
      • overriding aorta
      • VSD
      • RVH
48
Q

Describe the findings

A

Pericardiophrenic bundle

  • consists of the phrenic nerve, accompanied by an artery and a vein
  • CT findings:
    • artery is brightly seen
    • vein can also be seen (faintly)
  • Can be located on R or L sides
49
Q

Describe the findings

A

Muscular VSD

  • surrounded on all sides by myocardium
50
Q

Describe the findings / diagnosis

A

PAPVR - Scimitar syndrome

  • specific form of PAPVR in which all venous drainage from a particular lung (vast majority right lung) lobe drains into the IVC
  • syndrome is named for its appearance on frontal CXR wherein the anomalous pulmonary vein creates a crescent-shaped projection along the R sided cardiac border –> resembling a Turkish scimtar sword
  • Common associations:
    • hypoplastic right lung
  • Surgical repair is typically required
51
Q

Describe the findings

A

Unroofed coronary sinus

Medical (69 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions