3 Specific Imaging Finding for Chronic Ischemic Heart Disease
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12
Chronic Ischemic Heart Disease
a
Fig. 12.1 MRI of a patient with myocardial thinning on cine and fibrosis on delayed gadolinium-enhanced imaging (DE-MRI) following MI.
(a) Cine MRI with 4-chamber view shows myocardial thinning in api-
169
b
cal and lateral walls with dyskinesia (arrows) on systole. (b) DE-MRI
reveals hyperenhancement (arrows) with transmural involvement in
apex and partial thickness involvement in lateral wall
Table 12.1 Differential diagnosis between true aneurysm and pseudoaneurysm [4–7]
True aneurysm
Consists of an endocardium,
myocardium, and
epicardium ± thrombus
Wide neck/base
Low risk of rupture
Commonly anterior wall
Pseudoaneurysm
Consists of an epi-/
pericardium ± thrombus
Narrow neck/base
Higher risk of rupture
Commonly inferior wall
Marked enhancement of the
pericardium
12.3.4 Myocardial Fat Scarring
Fig. 12.2 MRI of a patient with pseudoaneurysm of LV in lateral wall.
Cine MRI with 4-chamber view shows a large wide-neck aneurysm in
lateral wall with thrombus (arrows)
• CT imaging usually reveals that the prevalence of myocardial fat scarring at LV is 22–62 % among patients with
a history of MI.
170
K.S. Choo and Y.H. Choe
a
b
Fig. 12.3 MRI of a patient with myocardial thinning and thrombus. (a) DE-MRI with 4-chamber view shows wall thinning (arrows) with hyperenhancement (arrows) and mural thrombus (arrowheads). (b) Cine MRI with 4-chamber view shows wall thinning (arrows) and thrombus (arrowhead)
a
b
Fig. 12.4 CT of a patient with myocardial fat scarring by healed MI. Cardiac CT (short-axis and 2-chamber views) shows subendocardial
myocardial fat scarring (arrows) at mid- to apical anteroseptal wall
• Myocardial fat scarring caused by healed MI is of thin
and linear or curvilinear configuration along the vascular
territory of culprit coronary artery [8].
• CT imaging studies usually shows subendocardial fat scarring of normal thickness or thin. Middle or subepicardial
layer of myocardial fat scarring has rarely been observed
(Fig. 12.4).
12.3.5 Myocardial Calcification
• Myocardial calcification is classified as either dystrophic
or metastatic [9].
• Dystrophic myocardial calcification is usually caused by
a large myocardial infarction and is reported to occur in
8 % of infarcts more than 6 years old (Fig. 12.5).
12
Chronic Ischemic Heart Disease
171
Fig. 12.5 CT of patient with linear myocardial calcification. Cardiac CT (short axis, 2-chamber, 4-chamber) shows curvilinear calcification with
wall thinning at LV apex and apical inferior wall
12.4
The Role of MRI for Differentiating
Between ICMP and Non-ICMP
• The main finding of differentiation between ICMP and
NICMP lies in the subendocardial or transmural DE along
the coronary vascular territory noted in the former compared to either no DE or a mid-wall or subepicardial DE
pattern seen in the latter.
• CT and stress MR perfusion can be also used in the evaluation of significant coronary artery disease for differentiating between ICMP and non-ICMP.
• DE pattern is likely secondary to a transient thrombotic or
embolic event with spontaneous recanalization sufficient
to cause the myocardial injury despite no obvious disease
on CCTA or stress MR perfusion as well as conventional
coronary angiography.
12.5
Summary
• CCTA could be a useful tool in excluding CAD in chronic
ischemic heart disease.
• CMR has become the reference of standard in the evaluation of myocardial viability in patients with ICMP.
• DE-MRI is a valuable tool for differentiating between
ICMP and non-ICMP.
References
1. Thygesen K, Alpert JS, White HD. Universal definition of myocardial infarction. Circulation. 2007;116:2634–53.
2. Mahrholdt H, Wagner A, Judd RM, Sechtem U, Kim RJ. Delayed
enhancement cardiovascular magnetic resonance assessment of
non-ischaemic cardiomyopathies. Eur Heart J. 2005;26:1461–74,
Fig. 3 Supplemental material.
3. Pretre R, Linka A, Jenni R, Turina MI. Surgical treatment of
acquired left ventricular pseudoaneurysms. Ann Thorac Surg. 2000;
70:53–7.
4. Frances C, Romero A, Grady D. Left ventricular pseudoaneurysm.
J Am Coll Cardiol. 1998;32:557–61.
5. Yeo TC, Malouf JF, Oh JK, Seward JB. Clinical profile and outcome in 52 patients with cardiac pseudoaneurysm. Ann Intern Med.
1998;128:299–305.
6. Yaymaci B, Bozbuga N, Balkanay M. Unruptured left ventricular
pseudoaneurysm. Int J Cardiol. 2001;77:99–101.
7. Konen E, Merchant N, Gutierrez C, Provost Y, Mickleborough L,
Paul NS, Butany J. True versus false left ventricular aneurysm: differentiation with MR imaging – initial experience. Radiology.
2005;236:65–70.
8. Kimura F, Matsuo Y, Nakajima T. Myocardial fat at cardiac imaging: how can we differentiate pathologic from physiologic fatty
infiltration? Radiographics. 2010;30:1587–602.
9. Gowda RM, Boxt LM. Calcification of the heart. Radiol Clin North
Am. 2004;42:603–17.
Part III
Non-ischemic Cardiomyopathy
