CARDIAC AA AMYLOIDOSIS SECONDARY TO FAMILIAL MEDITERRANEAN FEVER PRESENTING AS INTERMITENT COMPLETE HEART BLOCK: A RARE CASE WITH LITERATURE REVIEW

Abstract

SESSION TITLE: Medical Student/Resident Cardiovascular Disease Posters SESSION TYPE: Med Student/Res Case Rep Postr PRESENTED ON: October 18-21, 2020 INTRODUCTION: Cardiac amyloidosis is rare but relatively more frequently seen with ATTR and AL types of amyloidosis. AA amyloidosis related cardiomyopathy or conduction abnormalities are rare owing to less frequent involvement of the myocardium in AA amyloidosis. We present a case of complete heart block in the setting of AA amyloidosis secondary to familial mediterranean fever. CASE PRESENTATION: A 50-year-old female with history of familial mediterranean fever (FMF) presented with syncopal episode. On presentation patient's vitals were stable, labs including TSH were within normal limits. Orthostatic vitals were positive. High-sensitivity troponins were negative with a normal EKG on presentation. Laterally displaced apical beat was noticed on examination. During hospitalization patient was noticed to have complete heart block that was not responsive to atropine and transcutaneous pacing however a response was noticed with epinephrine drip. TTE revealed heart failure with reduced ejection fraction of 41% with severe concentric left ventricular thickening typical for amyloid cardiomyopathy with a well-preserved E/A-wave, which is not usually seen in as thickened ventricle as patients. CRP and SAA were elevated. Patient had endomyocardial biopsy that confirmed amyloid deposition staining positive for amyloid AA and negative for TTR, kappa and lambda and a technetium pyrophosphate scan was also negative. A biventricular pacemaker was placed for complete heart block without adequate escape rhythm, which resulted in resolution of episodes of dizziness associated with bradycardia. Patient's FMF was managed with colchicine and anakinra with the help of rheumatology. Patient was started on diuresis during hospitalization and continued on discharge. Patient followed up with amyloidosis clinic after discharge. DISCUSSION: Systemic amyloidosis is rare and results from deposition of amyloid deposits in various organs and hence a wide range of effects. Prognosis may be vary with the type and extent of amyloidosis. More than 95% of cardiac amyloidosis is secondary to light chain/AL amyloidosis or transthyretin amyloidosis (ATTR), both genetic/hereditary and wild type.[1] Cardiac involvement from AA amyloidosis is very rare. Cardiac amyloidosis usually manifests with syncope or postural hypotension, which may be related with bradyarrhythmias.[2] Like the involvement of cardiovascular system, developments of arrhythmias are also common with ATTR type of amyloidosis as compared to other types and may require pacemaker placement. AA cardiac amyloidosis is rare and bradyarrhythmias or conduction system involvement has also been rarely reported. We report a rare case of complete heart block secondary to AA amyloidosis from familial Mediterranean fever requiring pacemaker placement. CONCLUSIONS: We present cardiac AA amyloidosis as a rare cause of syncope and orthostatic hypotension. Reference #1: Sipe, J.D., et al., Amyloid fibril proteins and amyloidosis: chemical identification and clinical classification International Society of Amyloidosis 2016 Nomenclature Guidelines. Amyloid, 2016. 23(4): p. 209-213. Reference #2: Chamarthi, B., et al., Features and prognosis of exertional syncope in light-chain associated AL cardiac amyloidosis. Am J Cardiol, 1997. 80(9): p. 1242-5 DISCLOSURES: No relevant relationships by Usama Talib, source=Web Response