A Case Report of Cardiac Amyloidosis Presenting with Chest Discomfort

Introduction: Cardiac amyloidosis is one of the several systemic manifestations of amyloidosis. It is a relatively uncommon disease. Patients with cardiac amyloidosis clinically present with rapidly progressive heart failure. Case Presentation: We present a case of 64-year-old man with multiple episodes of chest discomfort accompanied sometimes with dyspnoea for the past several months. A non-specific ST-T changes with low voltage limb leads on ECG, a diastolic dysfunction with preserved ejection fraction on echocardiography, increased troponin and BNP, increased serum λ/κ light chain ratio led us to highly suspect amyloidosis with cardiac involvement. Abdominal fat pad biopsy confirmed the amyloid type change of subcutaneous fat, with immunohistochemistry revealing Lambda positive. After confirmed diagnosis of primary systemic amyloidosis with cardiac involvement, patient completed six cycles of chemotherapy with bortezomib and dexamethasone. The patient showed significant improvements after chemotherapy and supportive therapy. Conclusion: Amyloidosis is relatively fatal disease. Patients often have a short life expectancy after symptom onset. Early diagnosis is crucial to proper management and better prognosis.


Introduction
Amyloidosis is a multisystem disorder that results from extracellular deposition of insoluble amyloid protein in various organs.The most commonly affected organs are heart and kidney.The heart is involved in up to 50% of systemic primary amyloidosis [1], clinically presents with progressive dyspnoea and peripheral oedema [2].Cardiac involvement of amyloidosis has major impact on prognosis [3], with a median survival less than 6 months without treatment.
Endomyocardial biopsy is gold standard for diagnosing cardiac amyloidosis.
However, it is more invasive and much difficult to perform.Hence, abdominal fat pad biopsy is preferred over endomyocardial biopsy to establish definite diagnosis of systemic amyloidosis [4].We here present a case of primary systemic amyloidosis with cardiac involvement and clinical manifestation of multiple episodes of chest discomfort.

Case Report
A 64-year-old male smoker presented to our hospital with complains of multiple ECG showed non-specific ST-T changes with low voltage limb leads (Figure 1).

Discussion
Amyloidosis is a multisystem disorder due to deposition of insoluble amyloid fibrils that have characteristic β-pleated sheet configuration and produces apple-green birefringence under polarized light when stained with Congo red dye [5].The type of amyloidosis is defined by precursor protein.The most common amyloidosis is primary systemic amyloidosis, also called amyloid light chain (AL) amyloidosis, is caused when a person's antibody producing cells (plasma cells) do not function properly and produce abnormal protein fibres made of components of antibodies called light chains [6].Hence, it is often associated with other blood disorders, such as multiple myeloma and Waldenstrom's macroglobulinemia.
Amyloid deposition in the heart results in cardiac amyloidosis, clinically presents with rapidly progressive heart failure because of restrictive cardiomyopathy, and sometimes presents with typical angina due to amyloid deposition in arterial vessel wall causing progressive luminal narrowing and hence myocardial ischemia and impairment [7].Anish et al. described a case with cardiac amyloidosis presenting as recurrent acute coronary syndrome without coronary artery obstruction [8].Diagnosis of amyloidosis relies on clinical awareness of the disease, clinical features, blood and tissue analysis, and positive findings on biopsy.
For patients with heart involvement, the most common clinical feature is diastolic heart failure, which is manifested as progressive dyspnea.tive and the results are often disappointing [17].In our case, after starting chemotherapy, patient's heart failure symptoms relieved.The serum free light chain level was also decreased.It has been more than six months of confirmed diagnosis and patient condition has significant improvement.

Conclusion
Amyloidosis is uncommon, yet relatively fatal disease.In many patients, it is underdiagnosed or unrecognized.This results in increased morbidity and decreased life expectancy.Hence, early diagnosis is crucial to proper management and better prognosis.Since, prognosis is very poor, if diagnosis is delayed.Early institution of chemotherapy along with other supportive measures stabilizes amyloidogenic substance in blood, improves patient condition and prolongs life.

Funding
This study was supported by grant from Jilin Province Science and Technology Project (grant No. 20170520012JH) and National Natural Science Foundation (grant No. 81400279).

Holter
ECG revealed sinus bradycardia, occasional atrial extrasystole-couplet type, and paroxysmal atrial tachycardia.Echocardiography showed left atrial (46 mm) and left ventricular (58 mm) enlargement, along with increased thickness of basal interventricular septum (12 mm), segmental wall motion abnormality of left ventricle, E peak 83 cm/s; A peak 111 cm/s; TDI: E/e' > 15 with preserved ejection fraction (58%), aortic valve calcification and mild regurgitation of both mitral and aortic valve.Lung multi-slice CT had features of bronchitis with inflammatory changes and localized emphysema of bilateral lungs, thoracic aortic calcification and coronary artery sclerosis (Figure 2).Venous ultrasound of lower extremities had findings of subcutaneous oedema.Bone marrow aspiration and biopsy reported increased number of erythoid cells, plasmablasts accounting 1%, and presence of Mott cells.Abdominal fat pad biopsy confirmed B. K. Adhikari et al.DOI: 10.4236/wjcd.2018.82016164 World Journal of Cardiovascular Diseases

Figure 1 .
Figure 1.ECG reveals non-specific ST-T changes with low voltage limb leads.

Figure 2 .
Figure 2. Lung multi-slice CT showed bronchitis with inflammatory changes in both lungs and localized bilateral pulmonary emphysema, thoracic aortic calcification and coronary artery sclerosis.
[16]rn to normal in successful treatment.Regardless of recent advances in management, long term prognosis of cardiac amyloidosis is poor, especially if diagnosis is delayed[16].Several cases reported by Chandrashekhar et al concluded that despite intensive chemotherapy, cardiac treatment is suppor- In our case, patient complained of multiple episodes of chest discomfort from last 4 months, B. K. Adhikari et al.DOI: 10.4236/wjcd.2018.82016166 World Journal of Cardiovascular Diseases ECG frequently shows low voltage limb leads.First degree AV block is common and Q waves are frequently seen in leads V1 to V3.In cardiac amyloidosis, echocardiography generally reveals a pattern suggestive of infiltrative cardiomyopathy.In our patient, echocardiography revealed enlarged left atrium and left ventricle because of regurgitation present in both mitral and aortic valve.dulatory (thalidomide, lealidomide or proteasome inhibitor bortezomib) [15].The response to treatment is assessed by measuring free light chains in the B. K. Adhikari et al.DOI: 10.4236/wjcd.2018.82016167 World Journal of Cardiovascular Diseases blood, which