vealed no M spike . The PYP scan showed the myocardium to contralateral lung ratio was quantified at 1.06 , meaning that it was not likely to be ATTR amyloidosis . SFLC showed an elevated free lambda light chain , directing the diagnosis towards primary cardiac amyloidosis due to deposition of light chains .
More diagnostic tests were done to confirm the diagnosis . A fat pad biopsy and bone marrow aspirate were then collected . Fat pad biopsy was negative , but bone marrow aspirate showed a 10-15 % increase in plasma cells . From here , the gold standard ( cardiac biopsy ) was performed to confirm the diagnosis . Cardiac biopsy showed mild myocyte hypertrophy , scant interstitial fibrosis , and interstitial and arteriolar deposition of congo red positive material . Lambda light chain deposits were seen along with amyloid features on electron microscopy . These findings were consistent with AL lambda-type amyloidosis .
Heart failure treatment was started to improve the patient ' s symptoms and overall outcome . The patient was started on spironolactone , bumetanide , and metoprolol .
Discussion
This patient presented with a classic case of lambda light chain amyloidosis . Her chief complaint of shortness of breath in the absence of chest pain and a negative V / Q scan was suggestive of another underlying condition . The patient ' s abnormal echo with a severely hypertrophied left ventricle was indicative of infiltrative disease . Cardiac magnetic resonance suggested cardiac amyloidosis features that included a diffuse decrease in T1 and T2 signal intensity and diffuse left ventricular filling , with a ventricular septal wall measuring 2.1 cm . Confirmatory evidence was still needed to determine what type of amyloidosis she had . A positive SFLC informed us that she did have an infiltrative disease . PYP and bone marrow biopsy were completed . PYP was negative , which indicated that it was not likely to be ATTR , but an endomyocardial biopsy was done to rule out ATTR completely . Bone marrow biopsy was positive for clonal expansion of plasma cells . Endomyocardial biopsy showed amyloid aggregates that were of lambda light chain origin . These results reinforce her diagnosis of AL amyloidosis . 4 AL amyloidosis usually occurs in males over the age of 50 and typically involves one or more organs . It is vital to diagnose AL amyloidosis early because untreated patients with heart involvement have the most rapid disease progression . Diuretics are the primary drugs of choice for the patient ' s symptoms . Patients must follow up with a cardiologist for the management of their disease . Patients with AL amyloidosis in addition to cardiac involvement may be more sensitive than others to some cardiac drugs . For example , digoxin has cardiotoxic effects in amyloidosis patients . Also , calcium channel blockers and beta-blockers can be harmful to the patient , as they may lower blood pressure dramatically .
Specific goal-oriented therapy aims to halt the production of abnormal light chains by plasma cells . This can be achieved by a variety of chemotherapy drugs and other agents . With research underway , the goal of treatment of AL amyloidosis is moving toward patient-tailored therapy that might combine anti-amyloid treatments with anti-plasma cell chemotherapy . 5
ATTR is a protein misfolding disorder where transthyretin , a protein made in the liver , deposits in the nerves and other organ tissues . There are two forms of ATTR amyloidosis : hereditary and wild-type . The hereditary condition of ATTR has a mutation of the TTR protein that can be passed on from one generation to the next . Wildtype does not involve abnormal DNA and cannot be passed down . Instead , as you get older , your TTR protein is prone to becoming unstable and misfolding . This form of amyloidosis presents the same as AL amyloidosis . However , treating ATTR is very different . ATTR silencers like patisiran and inotersen act on the liver to decrease the production of TTR . ATTR stabilizers stabilize the TTR protein and prevent it from folding like tafamidis and diflunsial . Fibril disruptors like doxycycline and green tea extract have been found to help break up and clear ATTR fibrils . 6
By gaining information about the different cardiac amyloidosis types , physicians can better recognize the clinical signs and catch the disease early . This will help physicians develop multidimensional treatment plans and provide better patient education to those currently suffering from either AL amyloidosis or ATTR .
References
1 . Hearteditor . Case Study in Cardiac Amyloidosis : Daunting but Ever More Treatable . Consult QD .
2 . Witteles , R . and Liedtke , M ., 2021 . AL Amyloidosis for the Cardiologist and Oncologist : Epidemiology , Diagnosis , and Management . [ online ] JACC : CardioOncology .
3 . Yamamoto H , Yokochi T . Transthyretin cardiac amyloidosis : an update on diagnosis and treatment . ESC Heart Fail . 2019Dec ; 6 ( 6 ): 1128-1139 . doi : 10.1002 / ehf2.12518 . Epub 2019 Sep 25 . PMID : 31553132 ; PMCID : PMC6989279 .
4 . Sofie B , Natallia L , Bernhard G , Rahel S , Frank R , J . FA . Cardiac amyloidosis . Cardiovascular Medicine . https :// cardiovascmed . ch / article / doi / cvm . 2018.00592 . Published November 14 , 2018 .
5 . Quarta CC , C . Cristina Quarta From the Brigham and Women ' s Hospital / Harvard Vanguard Medical Associates Cardiac Amyloidosis Program ( C . C . Q ., Kruger JL , et al . Cardiac Amyloidosis . Circulation . https :// www . ahajournals . org / doi / full / 10.1161 / CIRCULATIONA- HA . 111.069195 . Published September 18 , 2012 .
6 . ATTR Amyloidosis ( Transthyretin ): Types , Symptoms & Treatment . Cleveland Clinic . https :// my . clevelandclinic . org / health / diseases / 17855-amyloidosis-attr #:~: text = Unlike % 20 hereditary % 20ATTR % 20amyloidosis % 2C % 20wild , misfolds % 20 and % 20forms % 20amyloid % 20fibrils .
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