Multimodalities Imaging of Immunoglobulin 4-related Cardiovascular Disorders

Epicardial Space: Comprehensive Anatomy and Spectrum of Disease

The epicardial space (ES) is the anatomic region located between the myocardium and the pericardium. This space includes the visceral pericardium and the epicardial fat that contains the epicardial coronary arteries, cardiac veins, lymphatic channels, and nerves. The epicardial fat represents the main component of the ES. This fat deposit has been a focus of research in recent years owing to its properties and relationship with coronary gossypiboma plaque and atrial fibrillation. Although this region is sometimes forgotten, a broad spectrum of lesions can be found in the ES and can be divided into neoplastic and nonneoplastic categories. Epicardial neoplastic lesions include lipoma, paraganglioma, metastases, angiosarcoma, and lymphoma. Epicardial nonneoplastic lesions encompass inflammatory infiltrative disorders, such as immunoglobulin G4-related disease and Erdheim-Chester disease, along with hydatidosis, abscesses, coronary abnormalities, pseudoaneurysms, hematoma, lipomatosis, and gossypiboma. Initial imaging of epicardial lesions may be performed with echocardiography, but CT and cardiac MRI are the best imaging modalities to help characterize epicardial lesions. Due to the nonspecific onset of signs and symptoms, the clinical history of a patient can play a crucial role in the diagnosis. A history of malignancy, multisystem diseases, prior trauma, myocardial infarction, or cardiac surgery can help narrow the differential diagnosis. The diagnostic approach to epicardial lesions should be made on the basis of the specific location, characteristic imaging features, and clinical background. ©RSNA, 2024 Test Your Knowledge questions for this article are available in the supplemental material.

Cardiac Masses and Pseudomasses: An Overview about Diagnostic Imaging and Clinical Background

A cardiac lesion detected at ultrasonography might turn out to be a normal structure, a benign tumor or rarely a malignancy, and lesion characterization is very important to appropriately manage the lesion itself. The exact relationship of the mass with coronary arteries and the knowledge of possible concomitant coronary artery disease are necessary preoperative information. Moreover, the increasingly performed coronary CT angiography to evaluate non-invasively coronary artery disease leads to a rising number of incidental findings. Therefore, CT and MRI are frequently performed imaging modalities when echocardiography is deemed insufficient to evaluate a lesion. A brief comprehensive overview about diagnostic radiological imaging and the clinical background of cardiac masses and pseudomasses is reported.

IgG4-related disease involving coronary and pulmonary arteries: a case report and literature review

Background

IgG4-related disease (IgG4-RD) is an inflammation-mediated autoimmune disease characterized by infiltration of IgG4 plasma cells in target organs, storiform fibrosis and obliterative phlebitis, accompanied by or without elevated serum IgG4 concentrations. Multiple sites can be involved, including large vessels. Coronary and pulmonary arteries are less involved, while simultaneous involvement of coronary and pulmonary arteries is less reported. This case is unique in terms of simultaneous involvement of coronary and pulmonary arteries in a female patient with possible IgG4-RD and the first review of relevant domestic literature.

Case Description

This case is a middle-aged female patient with both coronary artery and pulmonary artery involvement, with cardiac insufficiency as the main manifestation. Cardiac ultrasound revealed the cardiac insufficiency and abnormal wrapping of multiple arteries. Imaging examinations including coronary artery computed tomography angiography (CTA), pulmonary artery CTA and cardiac magnetic resonance imaging (MRI) further confirmed the lesions of the left main coronary artery, anterior descending branch, circumflex branch and pulmonary artery. Then the patient was diagnosed with possible IgG4-RD. After glucocorticoid treatment, the patient's clinical symptoms and cardiac function improved, and her serum IgG4 levels decreased.

Conclusions

When the arterial system is involved in IgG4 disease, it is known as IgG4-related artery disease. Combined with the case of this patient, this paper reviewed the literature on IgG4-related artery disease, and searched and summarized the related domestic literature on coronary/pulmonary artery disease to improve people's understanding of IgG4-related artery disease.

Coronary artery involvement in a patient with IgG4-related disease

Immunoglobulin G4-related disease (IgG4-RD) is a chronic fibro-inflammatory disorder of obscure etiology characterized by significant infiltration of IgG4-positive plasma cells toward several organs. Coronary artery involvement is rarely seen in IgG4-RD patients; thereby, we aim to outline the noninvasive imaging findings of this rare case. Cardiac magnetic resonance (CMR) and coronary computed tomography angiography (CCTA) from a 15-year-old female diagnosed with IgG4-RD via histopathological assessment of orbital biopsy, were analyzed. CMR showed a severely reduced left ventricular ejection fraction and akinesia of the basal to mid-lateral, anterior, and septal walls. Inflammation of the basal to apical lateral wall and subendocardial infarction of the basal to apical lateral and mid inferoseptal walls were also evident. CCTA findings showed stenosis in branches of the left main artery (LM), left anterior descending artery (LAD), and right coronary artery (RCA), aortitis, and aortic wall thickening. After courses of proper treatment with prednisolone, Cellcept, and adalimumab, follow-up CMR showed significant improvement in LV systolic function and resolution of inflammation. Although IgG4-RD is an uncommon cause of coronary artery disease, it can cause lethal complications such as myocardial infarction. Hence, clinicians should be aware of cardiac complications in these patients.

Cardiac manifestations of IgG4-related disease: a case series

Background

IgG4-related disease (IgG4-RD) is an autoimmune condition affecting almost every organ system, with an early inflammatory phase and later fibrotic consequences. Vascular manifestations, particularly, large-vessel involvement in IgG4-RD, are well described. However, important IgG4-related effects on medium-sized arteries and the pericardium are less well recognized. These less frequently reported cardiovascular effects of IgG4-RD include coronary artery stenosis, pericardial disease, cardiac masses, and valvular heart disease.

Case summary

This case series focuses on three patients that demonstrate the cardiovascular effects of IgG4-RD and the pitfalls and importance of early diagnosis. Cases 1 and 2 presented with cardiac manifestations prior to more typical organ systems being affected which led to a delay in diagnosis. Case 1 presented with an acute myocardial infarction secondary to IgG4-RD of the coronary arteries and Case 2 presented with pericarditis which progressed to pericardial constriction due to IgG4-RD. Case 3 already had a diagnosis of IgG4-RD from a prior renal biopsy which raised the index of suspicion that his pericardial disease and thoracic mass were also related to IgG4-RD.

Discussion

Cardiac manifestations of IgG4-RD remain under-recognized and include coronary artery and pericardial disease. These manifestations often precede more typical manifestations in other organ systems. Recognizing cardiac manifestations of IgG4-RD on cardiac imaging can raise clinical suspicion and act as a catalyst to ascertain a confirmatory diagnosis. Early diagnosis and treatment are crucial to prevent potentially fatal outcomes and irreversible fibrosis.

Therapy of immunoglonuline IgG4 related disease (IgG4-RD)

Immunoglobulin IgG4 related disease (IgG4-RD) is a heterogeneous disorder with multi-organ involvement recognised as a separate entity at the beginning of this century only. Evolving therapy is reviewed in this paper. Glucocorticoids are first choice drug but long administration of glucocorticoids is connected with many adverse effects. In case of combination glucocorticoids and immunosuppressive agents lower doses of glucocorticoids are needed, the response rate is higher and therapy is better tolerated. Rituximab is drug, that is possible use as monotherapy or in combination with glucocorticoids and immunosuppressive drugs. Only one study compared two immunosuporessive drugs, mycophenolate mofetil and cyclophosphamide. The response rated was similar but remissions were longer after glucocorticoids with cyclophosphamide then glucocorticoids with mycofenolat mofetil. No other comparative study of combination of various imunossupressive drugs with glucocorticoids was published. Rituximab has high number (90 %) of response rate in monotherapy, but can be used in combination with glucocorticoids and immunosuppressives. Rituximab is now preferred and recommended for maintenance therapy administered in 6-month interval. In case of advanced disease, we prefer therefore combination of rituximab, cyclofosphamide and dexamethasone for initial therapy followed by maintenance with rituximab in 6 months interval. There are two new drugs under investigation abatacept and dupilimab with promising results. Although we have very intensive therapies for good results of therapy early diagnosis before irreversible fibrotic changes in IgG4-RD involved organs is still needed.

Immunoglobulin G4-related masses surrounding coronary arteries: a case report

Background

Immunoglobulin G4 (IgG4)-related disease (IgG4-RD) is an immune-mediated fibroinflammatory condition with high serum IgG4 levels affecting various organs, such as the pancreas, lacrimal and salivary glands, thyroid, kidney, and lung. Typical cardiovascular manifestations of IgG4-RD include periaortitis, coronary arteritis, and pericarditis. However, reports of IgG4-RD associated with coronary arteritis are rare. Here, we report a case of IgG4-related masses surrounding the coronary arteries.

Case summary

A 59-year-old man was referred to our hospital because of mediastinal masses detected by computed tomography (CT). Coronary CT angiography revealed masses surrounding the right coronary artery and the left anterior descending coronary artery. An elevated serum level of IgG4 and histological findings led to the diagnosis of IgG4-related coronary arteritis with mass formation. Coronary angiography showed numerous feeding arteries to the masses, which were demonstrated as multiple microchannels in the intravascular ultrasound (IVUS) images.

Discussion

IgG4-RD involving the cardiovascular system has been reported. However, coronary artery disease associated with IgG4-RD is very rare, and the mechanism of mass formation in IgG4-related coronary arteritis is unclear. In our case, within the cardiovascular system, IgG4-RD was limited to the coronary arteries, suggesting that the affected coronary arteries may provide the necessary blood supply to the mass, thus, aiding its growth. These findings were supported by the images from coronary angiography and IVUS.

Immunoglobulin G4-related thoracic aortitis

Patients with immunoglobulin G4-related thoracic aortitis often have nonspecific symptoms, but pain in the chest or back is common. The rate of misdiagnosis of immunoglobulin G4-related thoracic aortitis is high, which may lead to mistreatment in extreme cases. A correct diagnosis should be based on comprehensive medical imaging, pathology, and laboratory and immunohistochemical results. Most patients' condition can be significantly improved using conservative or surgical treatment.

A challenging case report of IgG4-related systemic disease involving the heart and retroperitoneum with a literature review of similar heart lesions

The IgG4-related disease is a distinct, steroid-responsive fibro-inflammatory disorder of unknown etiology. This multiorgan disease is characterized by tumefactive lesions that contain rich infiltrations of IgG4-positive plasma cells, with the pancreas, and the salivary and lacrimal glands being the main involved. The more common cardiovascular involvements include inflammatory peri-aortitis, coronary arteritis, and pericarditis. Intra-cardiac tumefactive lesions are rarely reported. Herein, we describe a challenging case of IgG4-related disease with a long-time lag between initiation of symptoms to proper diagnosis with biopsy-proven cardiac and retroperitoneal and possible pituitary gland involvement. Concerning the rarity of the cardiac lesion in our case, we conducted a literature review of similar case reports.

Magnetic resonance imaging indicator of the causes of optic neuropathy in IgG4-related ophthalmic disease

Background

The following study investigates the involvement of optic neuropathy in IgG4-related ophthalmic diseases (IgG4-ROD) based on the magnetic resonance imaging (MRI) data, and different imaging features of IgG4-ROD related optic neuropathy related to other orbital diseases.

Methods

This retrospective study included 225 patients with IgG4-RD admitted at two ophthalmology centers between January 2014 and December 2017. Twenty-six patients had both pre-therapeutic orbital MRI and optic never injury. The causes of optic neuropathy were analyzed, and the special sign in MRI to diagnose IgG4-ROD was also evaluated.

Results

Twelve cases had inflammation of the optic nerve sheath, while 14 cases had compression due to extraocular muscles and pseudo tumor masses. Two cases had hypertrophic cranial pachymeningitis, while one case had hypophysis involving optic chiasma.

Conclusion

The most common causes of optic nerve injury in IgG-4 ROD are inflammation of optic nerve sheath, compression of extraocular muscles, pseudo tumor mass and hypertrophic cranial pachymeningitis, and hypophysis involving optic chiasma.