Introduction: Amyloidosis represents a systemic di-seases that results from extracellular deposition of fibrillar protein aggregates, with an abnormal con-figuration. Depending on the type, the infiltration of the myocardium by amyloid fibrils occurs in different proportion and has an important outcome concerning survival. Subtype identification has an important role in establishing treatment. New studies are trying to settle the bases for a multimodal imaging algorithm, that is useful not only for diagnosing amyloidosis, but also for identifying the subtype, some of the investiga-tions being equivalent to biopsy.
Objective: This case has the purpose of underlining the possibility of having a precise diagnosis and also dis-tinguishing between amyloidosis types by using serial multimodal imaging.
Methods: An 83 year-old man presents with progressi-ve dyspnea at rest, having multiple hospitalizations for heart failure (HF) symptoms, permanent atrial fibrilla-tion (AF) and hypertrophic cardiomyopathy and redu-ced ejection fraction, without clear etiology. At the ad-mission his BP is 120/70mmHg, HR=54bpm, irregular, systolic murmur at the aortic listening point, bilateral massive peripheral edema, congestive hepatomegaly and small pleural effusion. Laboratory test results show mild anemia (Hgb=11g/dl, MCV=87fL), inflammation (PCR=59mg/l, ESR=52/h, without leukocytosis). Elec-trocardiogram shows AF and ventricular ectopic beats and electric criteria for left ventricular hypertrophy (Sokolov-Lyon=40mm).
Results: Transthoracic echocardiogram reveals a hyperechoic, sparkly, granular interventricular sep-tum measuring 26mm and a posterior wall of 25mm, biventricular systolic dysfunction, (LVEF=30%, TAP-SE=14 mm) with normal ventricular volumes, grade diastolic dysfunction (LA index volume=52 ml/ m2), atrial septal thickening (9 mm). Two-dimensional speckle-tracking analysis shows relative apical sparing, raising the suspicion for cardiac amyloidosis as un-derlying cause for hypertrophic and restrictive cardi-omyopathy. Coronary angiography found noncritical stenosis. Cardiac MR sustains the diagnosis, revealing diffuse subendocardial late gadolinium enhancement, confirming the biventricular systolic dysfunctions and left ventricular hypertrophy. For subtype identification radionuclide bone scintigraphy with technetium-labe-led bisphosphonates (99m-Tc-HDP) was performed and it showed high cardiac uptake (grade III). Biopsy from subcutaneous tissue confirmed the diagnosis. The patient received treatment for heart failure, as there was no option for a specific treatment.
Conclusions: We presented a HF case, having as un-derlying cause TTR cardiac amyloidosis, that received a delayed diagnosis. Multimodal imaging established the diagnosis and identified the amyloidosis subtype. Bone scintigraphy showing grade III cardiac uptake, having 100% sensitivity and specificity for TTR amyloidosis, ruled out AL type. This approach is important, especi-ally for an old patient, on long-term anticoagulant the-rapy, in which case bone-marrow biopsy is associated with a high risk of complications. Distinction between wild type/hereditary type TTR amyloidosis was made based on clinical criteria: advanced age, slow disease progression, absence of extracardiac involvement. We ruled out the hereditary type, usually with a much fas-ter progression, early age onset and poor survival rates.