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Year : 2015 | Volume
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| Issue : 2 | Page : 176-178 |
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Imaging in constrictive pericarditis
Priya Jagia, Khemendra Kumar
Department of Cardiac Radiology, All India Institute of Medical Sciences, New Delhi, India
Date of Web Publication | 30-Sep-2015 |
Correspondence Address: Dr. Priya Jagia Department of Cardiac Radiology, All India Institute of Medical Sciences, New Delhi - 110 029 India
 Source of Support: None, Conflict of Interest: None  | Check |
DOI: 10.4103/2395-5414.166339
Raised right ventricular end-diastolic pressure and diastolic pressure equalization are accurate in only up to 85% causes in differentiating constrictive pericarditis from restrictive cardiomyopathy. Therefore imaging in the form of either computed tomography (CT) or magnetic resonance (MR) is important for clinching the diagnosis. In cases of diagnostic dilemma, cardiac MR (CMR) is the investigation of choice with its ability to show both morphological (increased pericardial thickness) and functional changes (constriction, septal bounce). CT for constrictive pericardium may be done if CMR is not available or when there is any contraindication to doing CMR. Keywords: Constrictive pericarditis, CT scan, imaging, magnetic resonance imaging
How to cite this article: Jagia P, Kumar K. Imaging in constrictive pericarditis. J Pract Cardiovasc Sci 2015;1:176-8 |
Constrictive pericarditis was first described in the literature by White [1] in 1935 and subsequently its surgical treatment was discussed. The etiological factors of constrictive pericarditis are many with tuberculosis being one of the commonest causes.
Imaging is required not only to diagnose chronic constrictive pericarditis (CCP) but also to rule out the important differential diagnosis of restricted cardiomyopathy. Echocardiography can demonstrate the increased pericardial thickness, which may not be uniform and is usually more than 3 mm, which is the reference range, in thickened pericardium. However, echocardiography may be limited in the evaluation of pericardial thickening anterior to the right ventricle and near the right atrioventricular groove. Raised right ventricular end-diastolic pressure and diastolic pressure equalization are accurate in only up to 85% causes in differentiating constrictive pericarditis from restrictive cardiomyopathy.[2] Hence, cross sectional imaging in the form of either computed tomography (CT) or magnetic resonance (MR) is important for clinching the diagnosis [Figure 1],[Figure 2],[Figure 3],[Figure 4],[Figure 5]. | Figure 1: Four chamber T1-.weighted magnetic resonance image showing thickening (arrow) of pericardium along the right ventricular free wall and right sided pleural effusion.
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 | Figure 2: Four chamber gated computed tomography image showing thickened calcified pericardium (arrow) along the anterior right ventricular wall with dilated atria and tubular elongated ventricles.
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 | Figure 3: Axial computed tomography image showing dilated inferior vena cava (black arrow) and superior vena cava (white arrow).
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 | Figure 4: Short axis cine magnetic resonance image is showing flattening of inter ventricular septum in diastole (white arrow).
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 | Figure 5: Four chamber computed tomography images showing enhancing thickened pericardium and loculated effusion (white arrow). Enlarged precarinal nodes with central necrosis (black arrowhead) and infiltrates in the right lower lung (solid white arrow) were seen.
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In cases of diagnostic dilemma, cardiac MR (CMR) is the investigation of choice with its ability to show both morphological (increased pericardial thickness) and functional changes (constriction, septal bounce) unlike nongated CT which shows only morphology.
CMR can accurately identify the pericardial anatomy and thickening. The pericardium is seen as a black membranous structure surrounded by the pericardial bright fat [Figure 1]. However, pericardial calcification cannot be picked up on MR through a dense calcification may be seen as a dark area. Functional assessment on CMR helps to demonstrate diastolic restriction on cine images which is best seen on four chamber and short axis images. There are ventricular elongation and reduction in end-diastolic volumes with left atrial dilatation along with superior and inferior vena caval dilatation [Figure 4].
If a good fat plane is seen between pericardium and myocardium, an easier dissection during the surgery can be predicted. Tagging sequences in CMR show distortion of tag lines at the area where pericardium “slips” over the underlying myocardium suggesting epicardial/pericardial tethering.[3]
On cine sequences, MR shows ventricular- ventricular interaction with evidence of a flattened interventricular spectrum or its convexity toward left ventricular (LV) in end diastole, suggesting high right ventricular pressures [4] [Figure 4]. Free breathing MR shows accentuation of these findings during deep inspiration. In inspiration, there is an increased venous return to the right heart and if constriction is present, the LV filling reduces and the septum flattens or becomes convex toward LV. The same is seen to be reversed on deep expiration.
Thus, besides showing the morphology, CMR also shows the functional changes which the cardiologists are accustomed to seeing on the echocardiography [Table 1].
CT for constrictive pericardium may be done if CMR is not available or when there is any contraindication to doing CMR. CT has the advantage of being able to show the pericardial calcification but has certain limitations as compared to MR. First, in cases where there is minimal or mild pericardial effusion; the exact pericardial thickening cannot be measured since it is difficult to differentiate the small amount of effusion from thickened pericardium. In such cases, MRI can show the pericardial thickness better. Second, unless gated, CT cannot show the functional changes associated with constriction. A gated CT, however, can show the diastolic restriction and the septal bounce. Constriction due to loculated effusion or pericardial abscess can be well seen on either CT or CMR. There may be evidence of thickened enhancing pericardium with other associated features of infection [Figure 2],[Figure 3] and[Figure 5].
It is important to remember that all the thickened pericardium does not cause constriction. Also, all constrictive pericarditis are not always associated with thickened pericardium. Hence, just a morphological assessment on CT or CMR showing thickened pericardium should not be interpreted as CCP. Other associated morphological findings such as elongated ventricles, flattened septum, dilated left atrium, dilated superior vena cava/inferior vena cava with or without pleural effusions can, however, be used to diagnose constriction even in the absence of functional assessment.
Financial support and sponsorship
Nil.
Conflicts of interest
There are no conflicts of interest.
References | |  |
1. | White PD. Chronic constrictive pericarditis (Pick's disease) treated by pericardial resection. Lancet 1935;2:539-48, 597-603. |
2. | Vaitkus PT, Kussmaul WG. Constrictive pericarditis versus restrictive cardiomyopathy: A reappraisal and update of diagnostic criteria. Am Heart J 1991;122:1431-41. |
3. | Kojima S, Yamada N, Goto Y. Diagnosis of constrictive pericarditis by tagged cine magnetic resonance imaging. N Engl J Med 1999;341:373-4. |
4. | Francone M, Dymarkowski S, Kalantzi M, Rademakers FE, Bogaert J. Assessment of ventricular coupling with real-time cine MRI and its value to differentiate constrictive pericarditis from restrictive cardiomyopathy. Eur Radiol 2006;16:944-51. |
[Figure 1], [Figure 2], [Figure 3], [Figure 4], [Figure 5]
[Table 1]
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