1) Coronary CT angiography (CCTA) uses computed tomography to non-invasively image the coronary arteries. It provides high quality images of the coronary arteries and their branches. 2) CCTA is performed using either electron-beam CT or multi-detector row CT (MDCT). MDCT is now more commonly used due to its wider availability and lower cost. The latest generation 64-detector MDCT allows for very high resolution imaging. 3) CCTA requires careful preparation of the patient including medication to control heart rate and dilation of the coronary arteries. The scan itself involves ECG gating to image the heart during diastasis and injection of iodinated contrast to outline the coronary

1. ANATOMY AND IMAGING OF CORONARY
ARTERY DISEASE WITH SPECIAL
REFERANCE TO CT CORONARY
ANGIOGRAPHY
Presented by– SARBESH TIWARI
PGT
1

2. Coronary artery
Coronary artery is a vasa
vasorum that supplies
the heart.
Coronary comes from the
latin ”Coronarius”
Meaning “Crown”.
2

3. Coronary artery
• The coronary artery arises just
superior to the aortic valve and
supply the heart
• The aortic valve has three cusps –
#left coronary (LC),
#right coronary (RC)
#posterior non-coronary (NC)
cusps.
3

4. Right coronary artery
• Originates from right
coronary sinus of
Valsalva
• Courses through the
right AV groove
between the right
atrium and right
ventricle to the
inferior part of the
septum 4

5. Branches of RCA
Right coronary artery
Conus branch
Conus artery
Sinu nodal artery
SINU NODAL BRANCH
Marginal artery
Post. Descending IV artery
AV nodalBranch
AV Nodal artery-
5

6. • Conus branch – 1st branch supplies the RVOT
• Sinus node artery – 2nd branch - SA node.(in 40% they
originate from LCA)
• Acute marginal arteries-Arise at acute angle and runs
along the margin of the right ventricle above the
diaphragm.
• Branch to AV node
• Posterior descending artery : Supply lower part of the
ventricular septum & adjacent ventricular walls.
Arises from RCA in 85% of case.
6

7. Right coronary anatomy
1 CONUS BR 2
RCA
AO
LA
RCA 3 AM 4
SAN RCA
7

8. RCA
AM
AM
8

9. Area of distribution
RT CORONARY ARTERY----
1)Right atrium
2)Ventricles
i) greater part of rt. Ventricle except the area adjoining
the anterior IV groove.
ii) a small part of the lt ventricle adjoining posterior IV
groove.
3)Posterior part of the IV septum
4)Whole of the conducting system of the heart, except
part of the left br of AV bundle
9

10. Left coronary artery
• Arises from left coronary
cusps
• Travels between RVOT
anteriorly and left atrium
posteriorly.
• Almost immediately
bifurcate into left anterior
descending and left
circumflex artery.
• Length – 10-15mm
10

11. 11

12. 12
LEFT CORONARY ARTERY

13. LT CORONARY ARTERY
1) Left atrium.
2) Ventricles
i) Greater part of the left ventricle, except the area
adjoining the posterior IV groove.
ii) A small part of the right ventricle adjoining the
anterior IV groove.
3) Anterior part of the IV septum.
4) A part of the left br. Of the AV bundle.
13

14. DOMINANCE
• Determined by the arrangement that which artery
reaches the crux & supply posterior descending
artery
• The right coronary artery is dominant in 85% cases.
• 8% cases - - circumflex br of the left coronary artery
• 7% both rt & lt coronary artery supply posterior
IVseptum & inferior surface of the left ventricle-here
it is balanced dominance.
14

15. ATHEROSCLEROSIS
15

16. Fatty streaks composed of lipid-laden macrophages (foam cells)
Fatty streaky progress to
plaque
Plaque :- Soft necrotic core of lipid with surrounding chronic inflammatory
cells covered by fibrous cap.
Progressively
enlarge causing Pressure atrophy of
critical stenosis the media causing
aneurysmal
dilatation
Ulcerates or ruptures
leading to thrombosis
and critical ischemia
16

17. Coronary pathology in acute coronary syndrome. The evolution of coronary
lesions follows a progression from (1) initial plaque formation, (2) plaque
growth, (3) plaque vulnerability and rupture, and (4) thrombosis.
17

18. IMAGING MODALITIES
18

19. Coronary Imaging Technique
• INVASIVE PROCEDURE:
1. CATHETER CORONARY ANGIOGRAPHY
2. INVASIVE ULTRASOUND
• NON INVASIVE PROCEDURE:
1. CHEST X RAY
2. ECHOCARDIOGRAPHY
3. COMPUTED TOMOGRAPHY
ELECTRON BEAM CT (EBCT)
MULTIDETECTOR CT (MDCT)
4. MAGNETIC RESONANCE IMAGING
5. NUCLEAR IMAGING.
19

20. CATHETER ANGIOGRAPHY
• A minimally invasive procedure to access coronary
circulation and blood filled chambers of the heart using
a catheter.
• The technique was first performed by Dr. Mason Sones
at the Cleveland Clinic in 1958
• The major epicardial vessels and their 2nd & 3rd order
branches can be visualized using coronary angiography.
• It is performed for both diagnostic and interventional
(treatment) purposes.
20

21. INDICATION
1. Diagnosis of CAD in clinically suspected pts.
2. Providing peri-interventional information for
percutaneous coronary intervention
3. Coronary anomalies
4. To exclude stenoses before non-coronary cardiac
surgery (valve surgery after 40 yrs of age)
5. Determine patency of coronary artery bypass grafts
21

22. CONTRAINDICATION
 Coagulopathy
 Decompensate congestive heart failure
 Uncontrolled Hypertension
 CVA
 GI Hemorrhage
 Pregnancy
 Inability for patient cooperation
 Active infection
 Renal Failure
 Contrast medium allergy
22

23. 23

24. PROCEDURE PROPER
• PATIENT PREPARATION:
1. Arrives at Cath. Lab at morning with at least 6 hrs.
fast
2. Allowed to take all medications as advised by
physician including aspirin except oral hypoglycemic
agents
3.Intravenous access is secured.
4. Sedation with benzodiazipine is recommended. 24

25. • Vascular Access: Seldinger
Technique is used.
Transfemoral route is MC
(transradial & transbranchial
routes can also be used).
• Catheter used- MC is Judkins
catheter.
• 3 different types are for Rt & Lt coronary artery
& Lt ventricle.(Lt ventriculography is followed
usually after cor. angio)
25

26. Catherization: Seldinger Technique
26

27. • Contrast media-Low osmolarity, Non-ionic
• Dose-3-10 ml;320-370 mg of iodine/mg, using a
hand-held syringe filled from a reservoir.
• Left coronary artery is filled with 6-8 ml, right
coronary artery is filled with 3-5 ml usually
27

28. Angiographic projection-
• The heart is oriented obliquely in the thoracic cavity,
the coronary circulation is generally visualized in the
RAO & LAO projection to furnish true PA & LAT
views of the heart. using both cranial & caudal
angulations.
• For LCA branches, views -
-AP ,RAO, LAO with cranial tilt
• For RCA branches, views reqd. are
-AP,RAO ,LAO ĉ or ĉout cranial
28

29. Angiographic view of LCA
29

30. Angiographic view of RCA 30

31. Pitfalls of coronary angiography
1. Inadequate vessel opacification- May give
impression of ostial stenoses, missing side branches
or thrombus.
2. Eccentric stenosis- Coronary atherosclerosis often
leads to eccentric or slit–like narrowing than central
narrowing; so if the long axis of the vessel is
projected, the vessel may appear to have a normal or
near normal caliber.
3. Superimposition of branches
4. Foreshortening of the stenotic segment due to
projectional defect
31

32. Rotational CA
• X-ray system rotates around the patient during the
acquisition of a single run
• Significant reduction in both contrast agent usage and
radiation dose of up to 30%, without compromising
image quality
• Contrast medium is injected automatically (3 mL /s for
the LCA and 2 mL/s for the RCA) range 12-18 cc
• After this preload, rotation of the C-arm was started
automatically and X-rays taken
32

33. Complication
-Overall mortality is about 0.2%.
# Vascular-hematoma, false aneurysm, AVF
# Cardiacarrythmia MI cardiac-arrythmia, MI
#contrastmedia induced-
heart failure, ECG changes,,allergic reaction
33

34. Tight stenosis noted involving A partially obstructive
the mid segment of right narrowing noted in the
coronary artery. Distal proximal segment of
branches are normal. the LAD
34

35. CORONARY CT ANGIOGRAPHY
(CCTA)
35

36. AVAILABLE TECHNOLOGY
• Currently, two competing CT technologies are used-
1. Electron-beam CT and
2. Mechanical multi–detector row CT
Electron beam CT :
# Used specifically for cardiac imaging d/t high temporal
resolution
# Uses a rapidly rotating electron beam, which is reflected onto
a stationary tungsten target
# Imaging done in sequential mode, where single transverse
sections are sequentially acquired.
# However, due to higher cost and limited availability, MDCT is
most commonly used.
36

37. CT CORONARY ANGIOGRAPHY
• Coronary computed tomography angiography (CCTA)
is an effective noninvasive method to image the
coronary arteries
• MDCT has multiple detector rows are placed opposite
the x-ray tube which shortens the examination time
and improves the temporal resolution
• The new generation 64 detector MDCT system has
allowed higher isotropic resolution, with visual clarity
of up to fifth- order coronary arterial branches.
37

38. Which ? MDCT is optimum
• 4/8-slice –For detection CAD sensitivity: 86% and
ruled out in 64 of 80 patients (specificity: 81%).
• 16 slice MDCT -sensitivity: 96% ,specificity: 83
• 64 slice CT -sensitivity: 97% ,specificity: 92%
38

39. • High-quality source images are the most important
prerequisite for the diagnostic assessment of coronary
CTA.
• Image quality depends on:
1. Heart rate – Image quality improves with heart rate
less than 65.
2. Proper coronary CTA scan and post processing
protocol.
3. The synchronization of raw image data with
electrocardiography (ECG) information
4. Breath Holding : 45 sec (4 detector) to 9 sec (64
detector)
39

40. INDICATION
• Screening high risk patients
• Evaluation of chest pain
• Post procedural study
Post CABG
Post stent
• Dilated Cardiomyopathy
• Non-cardiac surgery evaluation
40

41. CONTRAINDICATIONS
• Absolute contraindication :
1. Hypersensitivity to iodinated contrast agent
2. Pregnancy
 Relative contraindication
 Irregular rhythm
 Renal insufficiency (sr. creatinine > 1.5 mg/ml)
 Hyperthyroidism
 Inability to hold breath for 10 sec
 History of allergy to other medication
 Metallic interference (e,g: pacemaker, defibrillator
wires)
41

42. PATIENT PREPARATION
• Avoid caffeine and smoking 12 hours prior to the
procedure to avoid cardiac stimulation.
• B- blocker : Oral or I.V B-blocker is used in patient with
heart rate greater than 60 bpm
 oral 50- 100 mg metaprolol administered 45 min to 1 hr
before procedure.
 or I.V Metaprolol 5 to 20 mg at the time of procedure
 Sublingual Nitrates or Nitroglycerine: given immediately
before the procedure to dilated the coronary arteries.
42

43. Patient Positioning and Preparation for
Scanning
• Patients are positioned on the CT examination table in
the supine position
• ECG leads are attached to obtain an adequate ECG
tracing.
• Intravenous access via a large intravenous line (18
gauge cannula) is necessary to ensure easy injection of
the viscous contrast agent at a flow rate of 5 mL/s
• Training of patients with repeated breath holds
43

44. ECG gating protocols
• For ECG synchronized scanning of the cardiac
region, two different approaches are taken
1. Prospective ECG gating
2. Retrospective ECG gating
44

45. PROSPECTIVE ECG GATING
• Scan acquisition is triggered by the
ECG signal at the prospected mid-
diastolic phase of the cardiac cycle.
• Between 40% and 80% of the R-R
interval
• Benefits: Smaller patient radiation
dose
• Limitation: Reconstruction of image in
different cardiac phase for functional
analysis of ventricle is not feasible
45

46. RETROSPECTIVE ECG GATED SCANNING
 Heart region is scanned continuously
 Contiguous data of cardiac region are acquired
 Patient’s ECG is recorded at the same time
 Scan data with least cardiac motions , usually the
diastolic phase , are selected later for image
reconstruction
Advantage:
•Entire volume is acquired continuously and gapless
•Image may be reconstructed with overlap
Disadvantage:
• Higher patient radiation exposure
46

47. ECG controlled dose modulation
Diagram showing effect of ECG dose
modulation.
In Fig 1- continuous scanning
throughout the cardiac cycle with full
tube current , resulting in high radiation
dose.
In Fig 2- ECG dose modulation is
turned on and full tube current is applied
only during 40-80% of cardiac cycle,
where cardiac motion is least.
In Fig 3- To further decrease radiation,
a single phase of cardiac cycle is
selected for scanning during which full
tube current is applied.
47

48. Image acquisition and
reconstruction
• The acquisition of the dataset for coronary CTA
consists of 3 steps :
1. Topogram
2. Contrast medium protocol : to ensure
homogeneous contrast enhancement of the entire
coronary artery tree
3. Coronary CTA scan
48

49. TOPOGRAM
SCAN START POSITION
• Native coronary arteries
# Begin above carina
# Tortuous aorta or prominent
upper left heart border –
begin scan 1-2cm higher
• Bypass Grafts
 Veins: top of arch
 LIMA: above clavicles
SCAN ENDING POSITION
Image acquisition end 2 cm below the diaphragm
49

50. Contrast Medium Protocol
• Optimal coronary artery opacification depends
on :
1. The iodine medium concentration – (300-400
mg iodine/ ml is used)
2. The volume and rate of contrast
administration
3. Timing of the contrast medium delivery.
50

51. Volume and rate of contrast
administration
Using 64 detector MDCT technology:
• 80ml of contrast agent is injected at 6 ml/sec f/b
40ml saline solution at 4ml/sec
Using 16 detector MDCT technology:
• 100- 120 ml of contrast agent @ 4 to 5 ml per sec.
51

52. • Delivery of contrast medium s/b timed to ensure that the
scan of cardiac region will occur at the peak of opacification
of the coronary tree.
• It can be assessed by two techniques-
1. Automated contrast bolus tracker technique- the ROI is
placed on ascending aorta. When ct value of ROI is greater
than predetermined threshold of 100- 150 HU, the scan
begins.
2. Test bolus scan – here a small bolus of contrast is injected
to determine contrast transit time. The time from the start of
the injection to the peak contrast enhancement in the
ascending aorta determines the scan delay after the initiation
of contrast material administration.
52

53. • After contrast administration, CT is obtained in
single breath-hold
• Scan volume covers the entire heart from the
proximal ascending aorta (approximately 1–2 cm
below the carina) to the diaphragmatic surface of
the heart
53

54. Scanning protocol
54

55. Post processing protocol
• The axial source images obtained are utilized for
multiplanar reconstructions in at least 2 planes
• Commonly used techniques are :
Maximum intensity projection (MIP),
Volume rendering (VR),
Multiplanar reconstruction (MPR) or
Curved planar reconstruction (CPR
55

56. Curved multiplanar "Ribbon" multiplanar reconstruction
reconstruction (MPR) image (MPR)
3D Volume-rendering Maximum intensity projection56
(MIP)

57. RADIATION DOSE
• Ranges between 12-16 mSv depending on CT
scanner and type of ECG gating used.
• ECG-controlled dose modulation systems allows
reduction of radiation exposure by upto 50%
• Lower the KVP to 100 causes significant dose
reduction.
• A prospective gate window of 20% over diastole in
patients with HR of 60, can reduce total dose by
80%.
57

58. Coronary artery assessment
 The best evaluated coronary artery is the LAD as it runs
along the axis of the scan and is not significantly
affected by cardiac movements
 The LAD is well visualized in 76-96% of cases
 The left CX artery may be affected by cardiac motion
artifacts and can be assessed in 52-95% of cases
 RCA is most affected by cardiac movement
 Proximal coronary segments are better visualized than
distal ones.
58

59. ADVANTAGES OF MDTC
• Non invasive procedure without any hospital stay.
• MDCT CA can precisely identify total occlusion,
indicate cause and extent.
• Morphology of the occluded segment and the time the
artery was occluded
# In acute obstruction, low density intraluminal
defect caused by thrombosis with an increase in luminal
area and diameter are seen.
# In chronic cases , the obstruction shows
calcified or mixed plaques with the artery lumen with
normal or slightly narrowed lumen
59

60. • Predictors of failure to open an occluded artery
include
1.occlusion length greater than 15mm
2.Presence of severe calcification in the
compromised segment.
• Vessel distal to the completely obstructed segment is
visualized , not possible with catheter angio.
60

61. 61

62. Calcium scoring
• Coronary calcium screening is intended to detect
calcified atherosclerotic plaque burden as a
surrogate marker for coronary atherosclerosis.
• Based on the principle that–
# Obstructive atherosclerotic plaques
are calcified – so called “Hard Plaque”
# Calcium is not present within the wall
of a normal coronary artery
62

63. INDICATION
• Women over the age of 55 and men over the age of 45
should consider the coronary calcium scan, if they have
coronary artery disease risk factors:
---- Family history of heart disease
---- High cholesterol level (hypercholesteremia)
---- High blood pressure
---- Smoking, Obesity
---- Diabetes
---- High-stress lifestyle
63

64. Minimum requirement for calcium scoring
64

65. HOW THE PROCEDURE IS DONE
Preparation:
# No special preparation is necessary
# Avoid caffeine and smoking four hours before the
exam.
# Heart rate ＞ 90/min → β- blocker
Protocol :
# No contrast used
# 2.5 mm to 3 mm slice thickness
# Prospective ECG –gated acquisition for calcium
scoring.
65

66. • The threshold for calcification is set at an attenuation
value of ≥ 130 HU, for an area of > 1mm2 along the
course of the coronary arteries.
• For MDCT the threshold value for calcification is 90
HU ( because of high signal to noise ratio )
• Automated measurement of the lesion area in mm 2
and maximum CT No. (HU) of each lesions are
recorded.
66

67. • Density score of the lesions are determined as
• The total as well as individual coronary artery
calcium score is calculated using special software
at the workstation
67

68. Methods
• Quantitative calcium scores are calculated according to
the method described by Agatston et al .
Calcium score= density score x volume
• CAC scores are typically reported for each major
coronary artery (left main, left anterior descending,
circumflex, right coronary artery) separately
• The total score is achieved by adding up each of the
scores for all the slices
68

69. WHAT DOES THE CALCIUM SCORE REPRESENT
• Detection of any degree of coronary calcium on
CT indicates that CAD is present
• It provides a quantitative estimation of plaque
burden. Higher the score the larger the plaque
burden & higher the subsequent cardiac events.
• Score of zero indicates unlikely chance of CAD,
does not eliminate the possibility.
69

70. CALCIUM SCORING GUIDELINES
CALCIUM IMPLICATION RISK OF CORONARY
SCORES ARTERY DISEASE
0 No identifiable plaque Very low, less than 5%
1 – 10 Minimal identifiable plaque Very unlikely, less than 10%
11 – 100 Definite, at least mild Mild or minimal coronary
atherosclerotic plaque narrowing likely
101 - 400 Definite, at least moderate Mild coronary artery disease
plaque highly likely, significant
narrowing possible
401 or Extensive atherosclerotic High likelihood of at least one
higher plaque significant coronary narrowing
70

71. GUIDELINES FOR THE PHYSICIANS IN
INTERPRETING A PATIENTS SCORE
Presence of any detectable calcium
Implies presence of CAD
More aggressive BP control, lipid lowering
71

72. GUIDELINES cont….
Patients with high scores (>400)
likelihood of harboring a significant stenosis
Should undergo stress testing to evaluate
for inducible ischemia
72

73. GUIDELINES cont….
Patients with intermediate scores
Require further testing based on other
factors like age etc.
Score of zero
No need for further imaging tests for
Coronary disease
73

74. Advantages of Coronary calcium scoring
• Gives an idea of whether CAD is present, despite a
lack of symptoms or is likely to develop in next few
years develop in next few years.
• Non invasive and less time consuming.
• No contrast required needed.
• The examination can suggests the presence of CAD
even when the coronary arteries are <50%
narrowed.
74

75. LIMITATIONS
• Not all calcium deposits mean there is a blockade
and not all blocked arteries contain calcium.
• The earliest form of CAD soft plaque, cannot be
detected by cardiac CT.
• A high heart rate interferes with the test.
• Men <35 yrs and women <40 yrs are not likely to
benefit from cardiac CT for calcium scoring
unless there is risk factors such as diabetes or a
strong family history of heart disease.
75

76. Transthoracic echocardiography imaging of
coronary arteries
• With available technique, it is possible completely
evaluated left anterior descending and a part of
posterior descending artery.
• It is nowadays possible to investigate LAD in 98% of
patients and PDCA in 60–70% of patients
76

77. Transthoracic positioning of probe in order to
highlight the two major coronary arteries
77

78. Transducer beam orientations to the LAD and to posterior
descending CA with the corresponding echocardiography
images of the mid-distal tract of LAD.Pulse-wave flow and
posterior descending coronary artery (PDCA).
78

79. Stress Echocardiography
• Echo combined with exercise or pressor agents like
Dobutamine.
• There are two techniques for performing stress echo:-
a) Detection of wall motion abnormalities induced with
exercise/ dobutamine.
b) Measurement of altered myocardial perfusion on
contrast ECHO.
79

80. • The hallmark of myocardial ischemia during stress
echo is the occurrence of reduced systolic wall
thickening
• Precedes chest pain and ST-T wave changes, which
makes stress echo more sensitive than exercise
treadmill ECG testing.
• Limitation-
a) Poor inter-observer agreement
b) Optimal acoustic window may not be present in
every patient.
80

81. INTRAVASCULAR ULTRASOUND.
• Intravascular ultrasound (IVUS) is catheter based
imaging technique, using a specially
designed catheter with a miniaturized ultrasound probe
attached to the distal end of the catheter
• Allows the application of ultrasound technology to see
inside of coronary artery.
• Used in the coronary arteries to determine the amount
of atheromatous plaque
81

82. Procedure
Carried out during coronary
catheterization procedure
A miniature transducer
within a catheter is
introduced in vessel lumen
as distal as possible
Automatically pulled back @
0.5 mm/sec
82

83. 83

84. IVUS contd ….
Advantage :
1. visualization of complete circumference of vessel
wall as well as the plaque
2. allows stenosis measurement with direct
planimetry
3. evaluation of diffusely calcified ostial or bifurcation
stenosis.
Disadvantage :
1. Invasiveness
2. Cost.
84

85. MAGNETIC RESONANCE IMAGING IN CAD
• Coronary MRA has not gained acceptance for screening
of CAD.
• Difficulties for MRA-
# Small caliber of coronary artery-
LMCA- 4-6 mm
LAD, LCA & RCA- 3-4mm
# Tortuous course
# Respiratory motion Artifacts
# Coronary artery motion artifacts during cardiac cycle
85

86. • When properly executed, the breath-hold technique
with cardiac gating yields extremely good quality
images of the coronary arteries
• Navigator-echo Sequence makes up for the
respiratory movements with some degradation of
image quality
• Accuracy of MRA in these proximal segments was
approximately 90%
86

87. MAGNETIC RESONANCE IMAGING
• First choice in evaluation of proximal coronary
pathology in young and in particular if associated
congenital anomalies are present
• The limitations for imaging the distal coronary arterial
segments remain
• The use of contrast agents improve the signal-to-
noise ratio in these distal coronary branches
• In future with the advent of shorter scan times better
post processing software -the diagnostic accuracy of
3D, navigator-echo MR angiography will increase
87

88. Advantages of Coronary MRI
 No radiation and minimal invasiveness (IV
injection)
 3-dimensional anatomic images (3D coronary
artery and myocardial imaging)
 Comprehensive functional imaging
- Myocardial mechanical work
 - Myocardial perfusion
 - Myocardial oxygenation
 - Myocardial Viability
88

89. Detailed view on the right coronary artery in the atrioventricular groove
between the right ventricle (RV) and atrium (RA). The arrows indicate
stenoses in the proximal and mid segment. (B) Corresponding
conventional coronary angiogram.
89

90. Example of a significant stenosis (arrow head) in the left anterior descending
coronary artery (LAD). (A) Conventional coronary angiogram. (B) Magnetic
resonance imaging. Ao, aorta; LM, left main; LV, left ventricle; RVOT, right
ventricular outflow tract.
90

91. MYOCARDIAL PERFUSION IMAGING
• Thallium-201/Technetium 99m labelled agents like
Tc99m-sestamibi are used in MPI.
• Principle- During stress, blood flow increases in
normal coronary arteries but not in stenosed artery.
As a result, myocardium distal to the stenosis remains
hypoperfused.
• Represented as regions of decreased perfusion on
stress images.
91

92. Coronary artery anomalies
• Occurs in 0.3 to 1% of general population
• Important cause of sudden cardiac death.
• Can be hemodynamically significant
(Malignant) or insignificant (Benign).
92

93. Congenital variation of coronary anatomy
• Angelini has suggested classifying coronary
anomalies into three categories:
1. Abnormalities of the coronary ostia:
a) High Take off
b) Multiple ostia
c) Single coronary artery
d) Anomalous origin of coronary artery from
pulmonary trunk
e) Origin of coronary artery or branch from
opposite or noncoronary cusp with abnormal course
93

94. 2. Anomalous course:
a) Myocardial bridging
b) Duplication of arteries
3. Anomalies of termination:
a) Coronary artery fistula
b) Coronary arcade
c) Extra cardiac termination.
94

95. Single coronary artery .(a)Oblique VR image of the top of the heart shows only one
coronary artery arising from the left coronary sinus. The RCA (arrow) courses between
the aorta(A)and the pulmonary artery(PA).(b)On a sagittal oblique VR image, the single
coronary artery demonstrates a high takeoff (arrowhead) above the sinotubular junction.
95

96. Coronary anomalies
A. Benign or Minor Coronary Anomalies
1. Left Cx artery arising from right aortic sinus –
Most common
2. Independent origin of LAD artery and Cx
from the left aortic sinus –
The absence of LMCA is the common anomaly
of the left coronary vessel system.
96

97. Malignant or major coronary Anomalies
1. RCA arising from left coronary sinus:
Most common malignant coronary anomaly.
Present in 20—25% of cases. RCA has inter-arterial
course and prone for compression
97

98. Contd…..
2. LMCA arising from right aortic sinus :
LMCA courses between aorta and pulmonary
artery. 60 % die before are 20 during sternous
exercise.
98

99. 3. Anomalous origin of LMCA, LAD or RCA from the
pulmonary trunk:
Anomalous origin of LMCA is called Blant-White-
Garland syndrome, whereas if anomalous origin of RCA
is called reverse Blant-White-Garland syndrome.
99

100. 4. Coronary Artery fistula:
communication between one or
two coronary arteries and a
cardiac chamber or systemic vein.
Large AV communication produce
myocardial perfusion deficit.
5. Myocardial bridging:
Epicardial segment of a coronary
artery tunnels through a
portion of myocardium.
Involves middle segment of LAD.
100

101. CORONARY ARTERY DISEASES
101

102. What is coronary artery disease ?
• Coronary artery disease (CAD) is a complex disease
due to reduced or absent blood flow in one or
more of the arteries that supply the heart.
• Excluding congenital anomalies , it is usually caused
by atherosclerosis.
102

103. 1. Atheromatous coronary artery disease
• Typical major coronary artery branches have internal
diameter of 2.5-3.5 mm; LCA having internal diameter
of about 4mm.
• Atheromas due to chronic endothelial injury
• Flecks of calcification - indicate obstructive
atheromatous disease.
• Calcification is the rationale for using CT to detect
asympt. CAD.
103

104. • A reduction in lumen diameter >60% is enough
to represent a hemodynamically significant
stenosis.
• Chronic increase of size of plaque leads to stable
angina or ischemic cardiomyopathy.
• Acute changes, especially plaque rupture lead to
a variety of “acute coronary syndrome” most
imp. are unstable angina & MI.
104

105. Conditions result from CAD is :-
1. Angina Pectoris
2. Myocardial Infarction
ANGINA PECTORIS: Symptom complex caused
by transient myocardial ischemia d/t fixed
atheromatous stenosis of one or more arteries.
Types : It has 3 types :--
1.Stable Angina
2. Un stable angina &
3.Variant Angina (Prinzmetal’s or resting
angina)
105

106. Myocardial Infarction
• Irreversible necrosis of heart muscle secondary to
prolonged ischemia
• Presents with prolonged chest pain, anxiety,
breathlessness and collapse
• Sudden cardiac death can occur d/t ventricular
fibrillation.
• Diagnosed by raised cardiac biomarker
• Role of imaging comes after initial stabilization of the pt.
106

107. Coronary Artery Disease
2) Aneurysm of coronary artery
# Atheromatous-may lead to
localized or part of generalized
ectasia.
Symptom or death by rupture
or pressure on the parent artery
or by distal embolisation.
# Inflammatory -‘Kawasaki
Syndrome’(mucocut.
L.N.syndrome)-Aneurysm &
stricture of cor. artery in
children
107

108. Imaging of coronary arterial and heart disease
X-Ray findings
i) Coronary artery calcification :Best seen in proximal LCA &
may be identified near the aortic root on both PA & Lat.
commonly in pts. >70 yrs.
In pts <50yrs calcification -calcified atheromatous
plaque.
ii) Acute MI
----- CXR is normal in acute phase(within 24 hrs)
----- Later changes –
# Upper lobe diversion PVH, Septal thickening
# Alveolar pulmonary edema MC feature identified.
# Pleural effusion if there is prolonged left heart failure.
Progressive cardiomegaly occur more often in
anterior MI it is a bad prognostic sign.
108

109. iii) Acute MR:
# It is usually due to dilatation of mitral valve annulus
or papillary muscle rupture.
# Cardiomegaly with or without PVH.
# CXR feature is same as in other cause of MR
iv) Rupture of IV septum: rare complication.
# It is between 4-21 days infarction.
# Pulmonary plethora & pulmonary edema.
v) Lt ventricular rupture: it is a common complication.
# Pericardial tamponade occurs-leads to death
109

110. vi) Lt ventricular aneurysm: MC complication in clinical
practice.
# Occurs if the infarcted segment is large.
# Most Commonly in the cardiac apex in assoc. with
anterior infarct.
# Localized bulge on the left heart border on CXR, but
may not be seen if aneurysm is not well demarcated.
# Curvilinear calcification in the walls of aneurysm after
several yrs.
vii) Pericardial effusion: Most commonly associated with
partial ventricular rupture.
Mild cardiomegaly on CXR.
110

111. 111

112. ECHOCARDIOGRAPHY
 Ostia of main coronary arteries may be imaged.
 Helps in distinguishing anomalous origin of coronary
arteries presenting with lt ventricular disease, dilated
cardiomyopathy, or myocarditis.
 Useful in detecting coronary artery aneurysm e.g.
Kawasaki disease.
 Transthoracic & transesophageal USG can be
helpful in imaging proximal rt & lt coronary artery.
 Echo is the tech. of choice for detection &
quantification of ventricular aneurysm & detection of
concomitant thrombus.
112

113. STRESS ECHO:
A stressor stimulus e.g. exercise or a pharmaceutical
agent like Dobutamine is applied & then followed be
echo.
Improves sensitivity for detecting CAD.
MYOCARDIAL PERFUSION IMAGING:
Radioactive tracer (Thallium201, Technitium-99m
labeled tracer) is injected and scintigrams are
obtained at rest and during stress.
A perfusion defect during stress but not at rest provides
e/o reversible myocardial ischemia.
113

114. Coronary CT angiography
• Best non invasive modality for depiction of
coronary artery anatomy and disease
• Evaluates the plaque burden and morphology
accurately
• Important “ rule –out” modality in patients with
atypical chest pain
• Technique of choice to evaluate bypass graft.
• Dose limiting techniques, coupled with adherance
to ALARA principle may shift the risk-benefit ratio
in favour of this modality.
114

115. CARDIAC MRI
Cardiac MRI is a established tool in assessing
congenital heart disease & diseases of aorta &
pericardium, but role in coronary artery evaluation
is not very significant.
—These noninvasive techniques are useful in initial
screening for coronary artery stenosis , evaluating
bypass grafts and determining the patency of
infarct related artery after coronary thrombolysis.
115

116. Imaging in post bypass surgery and stent
patients
• CCTA is highly recommended for follow up
evaluation of CABG.
• Unlike invasive coronary angiograms, MDCT does
not require accurate localization of Ostia of venous
graft for selective contrast injection.
• Sensitivity of 97-100 % for graft stenosis/occlusion
• However, surgical metallic clips may lead to artifact
116

117. • Routine application of CT to assess patients with
coronary stents is currently not recommended.
• Visualization of the stent lumen is often affected
by artifacts, and especially the PPV is low.
117

118. 118

119. Fig. LAD thrombus demonstrated with MDCTA. A: Patient with a thrombus in the
LAD (arrow). B: Multiplanar reformatting of the same data set demonstrating the
extent of the thrombus formation in the LAD. C: In the coronary angiogram, only
slightly diminished enhancement is visible at the corresponding location
119

120. Fig. Stenosis of LAD demonstrated with MDCTA. A: 55-year-old
male patient with a single-vessel disease in the LAD (arrow). B:
Finding of CTA confirmed by cardiac catheter with a high-grade
stenosis in the midsegment of the LAD.
120

121. Fig. Acute coronary syndrome. anterior wall
perfusion deficits on short axis was
noted(A) and vertical long axis (B)
reconstructions are seen, including
subendocardial components (thin arrows). C:
A reconstructed image to detail the coronary
arteries shows a filling defect (yellow arrows)
occluding the LAD and smaller nonocclusive
plaques (white arrows) in a large diagonal
branch. Note the cardiac vein (blue
arrowhead) immediately posterior to the
121
diagonal branch.

122. 122

123. Conclusion
• Non- invasive cardiac imaging is now central to
diagnosis and management of CAD patients, however
cannot replace existing modalities
• ECHO c/be performed bedside and is advantageous
for acutely ill patients
• Cardiac catheterization offers the option of
intervention
• Myocardial perfusion scanning and MDCT can be
offered to patients with intermediate likelihood of
CAD
123

124. • MDCT c/become investigation of choice for
evaluation of bypass graft in CABG patients
• Currently CMR lags behind CTA for non invasive
coronary angiography, it is already emerged as a
highly effective method for assessing ventricular
function , myocardial mass and myocardial
viability.
124

125. 125