A 53-year-old man came to our hospital with signs and symptoms of acute heart failure after a 2-week history of progressive breathlessness.
He had a history of recurrent skin abscesses and atopic dermatitis and regularly visited a dermatologist in our hospital.
On arriving at our hospital, his extremities were warm and dry.
According to the New York Heart Association criteria, he had class III congestive heart failure (CHF).
An electrocardiogram revealed diffuse nonspecific T-wave changes, low voltage (<5 mm) in the extremity leads and poor R-wave progression in the anterior chest leads.
Multiple sporadic ventricular premature beats were seen (Figure 1).
Chest x-ray film confirmed right pleural effusion, and mild cardiomegaly but no pulmonary congestion (Figure 2).
Blood tests showed severely elevated B-type natriuretic peptide (901 pg/mL) and markedly raised IgE (12 000 IU/mL) without eosinophilia (eosinophil count of 1.62×108/L).
Biochemical analysis revealed no significant findings: blood urea nitrogen of 14.3 mg/dL [reference value (RV): 7.00–22.00], creatinine of 0.90 mg/dL (RV: 0.60–1.00), C-reactive protein (CRP) of 0.2 mg/dL (RV: 0.00–0.50), serum amyloid A (SAA) of 7.0 μg/mL (RV: 0–8.0), and troponin T of 0.07 ng/mL (RV: 0–0.1).
Immunology testing revealed negative perinuclear anti-neutrophil cytoplasmic antibodies and no elevation of myeloperoxidase antibodies.
The distribution of albumin and globulin in the serum was normal.
Serum protein immuno-electrophoresis did not reveal M-protein, and urinalysis revealed no Bence-Jones protein.
Transthoracic echocardiography (Figure 3) showed concentric mild left ventricular (LV) hypertrophy (12 mm) without the characteristic granular sparkling appearance and pericardial effusion, preserved ejection fraction (60%), and bi-atrial enlargement with normal ventricular chambers.
Doppler-derived LV diastolic filling demonstrated a restrictive pattern with a trans-mitral early filling wave deceleration time of 160 ms and an elevated E/A ratio of 2.8.
A markedly elevation of E/e’ ratio of 27.3 indicated elevated LV filling pressure.
On day 1 of hospitalization, we prescribed an angiotensin-converting enzyme (ACE) inhibitor and low-dose diuretics.
On day 3 of hospitalization, after initiating ACE inhibitor and diuretic therapy, the patient’s symptoms resolved.
The dermatologists performed a biopsy of a blue macula of the forehead skin.
On day 4, we introduced a low-dose β-blocker and performed an endomyocardial biopsy (EMB), obtaining 3 fragments of the right ventricular septum because diagnostic confirmation of cardiac amyloidosis requires the demonstration of amyloid deposits.
In addition, we performed right heart catheterization (RHC), and coronary angiography to exclude obstructive coronary artery disease.
The data obtained from the RHC indicated subset type IV according to the Forrester classification.
The right ventricular pressure curve did not show a dip-and-plateau configuration.
Skin biopsy revealed hyperkeratosis in the epidermis and mild inflammatory changes throughout the dermis with an infiltration of lymphocytes.
The specimen exhibited apple-green birefringence with polarized light after Congo red staining (Figure 4).
Histological examination of the myocardial specimen showed no signs suggesting myocarditis, eosinophilic granulomas, or cardiomyopathy with iron deposition, but Congo red staining revealed amyloid deposits (Figure 5).
In addition, a strongly positive immunohistochemical reaction to immunoglobulin λ-chain in the myocardial interstitium led us to diagnose this patient’s systemic amyloidosis as AL amyloidosis.
The patient generally tolerated the low-dose β-blocker well and was discharged on day 10 with no complications.
The patient is currently being followed-up at 6-month intervals as an out-patient, with no exacerbation of the CHF thus far.