Magnetic Resonance Imaging for the Detection of Myocardial Fibrosis in Scleroderma
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《新英格兰医药杂志》
To the Editor: A 65-year-old woman with diffuse scleroderma presented with increasing dyspnea on exertion, fatigue, and approximately a six-week history of palpitations. She had a history of scleroderma-related pulmonary fibrosis, which was clinically stable, but no ischemic heart disease or other cardiomyopathy. Physical examination revealed pedal edema and neck-vein distention, consistent with right heart failure. Electrocardiography showed frequent atrial and ventricular premature beats, right bundle-branch block, and left anterior fascicular block. There was evidence of biventricular diastolic dysfunction on two-dimensional echocardiography. Cardiac enzymes were within the normal range on repeated measurements.
On cardiac magnetic resonance imaging (MRI), the cine gradient–echo sequences revealed hypokinetic and dyskinetic areas involving the right ventricular free wall, as well as aneurysms of the right ventricle and right ventricular outflow tract (Figures 1A and 1B). The left ventricular ejection fraction was 54 percent; the end-diastolic and end-systolic volumes were 66 cm3 and 44 cm3, respectively. The right ventricular ejection fraction was 47.5 percent, with right ventricular end-diastolic and end-systolic volumes of 83 cm3 and 44 cm3, respectively. Gadolinium-enhanced MRI revealed hyperenhancing areas in the myocardium of the right ventricle and the interventricular septum (Figure 1C), probably caused by myocardial fibrosis. There was no evidence of an increase in signal intensity on the T2-weighted image.
Figure 1. Cardiac MRI Showing Myocardial Fibrosis.
Images of the right ventricular long axis at end diastole (Panel A) and at end systole (Panel B) show the irregular shape of the right ventricular free wall (black and dark gray areas), with aneurysms (arrows) bulging during both diastole and systole. A delayed contrast-enhanced MRI image in the short-axis plane (Panel C) shows increased enhancement (white and light gray areas) of the right ventricular myocardium (arrows) and the interventricular septum (arrowhead) caused by myocardial fibrosis.
Myocardial fibrosis, the hallmark of cardiac involvement in systemic sclerosis, accounts for the majority of cardiac manifestations in patients with scleroderma. Its detection and histologic confirmation are difficult because of an often-asymptomatic course, nonspecific findings by noninvasive techniques, and patchy distribution in the myocardium.1 Early and accurate diagnosis of fibrosis is important, especially when treatment is considered to prevent the potentially lethal consequences. Because of its noninvasive nature, high spatial resolution, and lack of nephrotoxicity, delayed contrast-enhanced cardiac MRI2 appears to be superior to other techniques in the detection of myocardial involvement in a wide range of systemic diseases affecting the heart, such as amyloidosis3 and sarcoidosis.4,5 In our patient, cardiac cine MRI revealed multiple aneurysms in the free wall of the right ventricle, which were distributed in a nonvascular region and corresponded to areas of hyperenhancement. These findings, in conjunction with normal cardiac enzyme levels and the absence of an increase in the T2-weighted signal, suggest myocardial fibrosis rather than myocarditis. In this particular patient group, delayed contrast-enhanced MRI may prove to be a useful tool for screening for myocardial fibrosis, monitoring the progression of the condition, and possibly evaluating the effects of therapeutic intervention.
Sotiris C. Plastiras, M.D.
Nikolaos Kelekis, M.D.
George E. Tzelepis, M.D.
University of Athens Medical School
11527 Athens, Greece
gtzelep@med.uoa.gr
References
Fowles RE, Mason JW. Endomyocardial biopsy. Ann Intern Med 1982;97:885-894.
Beller GA. Noninvasive assessment of myocardial viability. N Engl J Med 2000;343:1488-1490.
Kwong RY, Falk RH. Cardiovascular magnetic resonance in cardiac amyloidosis. Circulation 2005;111:122-124.
Smedema JP, Snoep G, van Kroonenburgh MP, et al. The additional value of gadolinium-enhanced MRI to standard assessment for cardiac involvement in patients with pulmonary sarcoidosis. Chest 2005;128:1629-1637.
Serra JJ, Monte GU, Mello ES, et al. Cardiac sarcoidosis evaluated by delayed-enhanced magnetic resonance imaging. Circulation 2003;107:e188-e189.
On cardiac magnetic resonance imaging (MRI), the cine gradient–echo sequences revealed hypokinetic and dyskinetic areas involving the right ventricular free wall, as well as aneurysms of the right ventricle and right ventricular outflow tract (Figures 1A and 1B). The left ventricular ejection fraction was 54 percent; the end-diastolic and end-systolic volumes were 66 cm3 and 44 cm3, respectively. The right ventricular ejection fraction was 47.5 percent, with right ventricular end-diastolic and end-systolic volumes of 83 cm3 and 44 cm3, respectively. Gadolinium-enhanced MRI revealed hyperenhancing areas in the myocardium of the right ventricle and the interventricular septum (Figure 1C), probably caused by myocardial fibrosis. There was no evidence of an increase in signal intensity on the T2-weighted image.
Figure 1. Cardiac MRI Showing Myocardial Fibrosis.
Images of the right ventricular long axis at end diastole (Panel A) and at end systole (Panel B) show the irregular shape of the right ventricular free wall (black and dark gray areas), with aneurysms (arrows) bulging during both diastole and systole. A delayed contrast-enhanced MRI image in the short-axis plane (Panel C) shows increased enhancement (white and light gray areas) of the right ventricular myocardium (arrows) and the interventricular septum (arrowhead) caused by myocardial fibrosis.
Myocardial fibrosis, the hallmark of cardiac involvement in systemic sclerosis, accounts for the majority of cardiac manifestations in patients with scleroderma. Its detection and histologic confirmation are difficult because of an often-asymptomatic course, nonspecific findings by noninvasive techniques, and patchy distribution in the myocardium.1 Early and accurate diagnosis of fibrosis is important, especially when treatment is considered to prevent the potentially lethal consequences. Because of its noninvasive nature, high spatial resolution, and lack of nephrotoxicity, delayed contrast-enhanced cardiac MRI2 appears to be superior to other techniques in the detection of myocardial involvement in a wide range of systemic diseases affecting the heart, such as amyloidosis3 and sarcoidosis.4,5 In our patient, cardiac cine MRI revealed multiple aneurysms in the free wall of the right ventricle, which were distributed in a nonvascular region and corresponded to areas of hyperenhancement. These findings, in conjunction with normal cardiac enzyme levels and the absence of an increase in the T2-weighted signal, suggest myocardial fibrosis rather than myocarditis. In this particular patient group, delayed contrast-enhanced MRI may prove to be a useful tool for screening for myocardial fibrosis, monitoring the progression of the condition, and possibly evaluating the effects of therapeutic intervention.
Sotiris C. Plastiras, M.D.
Nikolaos Kelekis, M.D.
George E. Tzelepis, M.D.
University of Athens Medical School
11527 Athens, Greece
gtzelep@med.uoa.gr
References
Fowles RE, Mason JW. Endomyocardial biopsy. Ann Intern Med 1982;97:885-894.
Beller GA. Noninvasive assessment of myocardial viability. N Engl J Med 2000;343:1488-1490.
Kwong RY, Falk RH. Cardiovascular magnetic resonance in cardiac amyloidosis. Circulation 2005;111:122-124.
Smedema JP, Snoep G, van Kroonenburgh MP, et al. The additional value of gadolinium-enhanced MRI to standard assessment for cardiac involvement in patients with pulmonary sarcoidosis. Chest 2005;128:1629-1637.
Serra JJ, Monte GU, Mello ES, et al. Cardiac sarcoidosis evaluated by delayed-enhanced magnetic resonance imaging. Circulation 2003;107:e188-e189.