Senile Systemic Amyloidosis Presenting With Heart Failure A Comparison With Light Chain-Associated Amyloidosis

TLDR: The difference in survival, despite evidence of more myocardial disease in the senile group, suggests that heart failure in AL amyloidosis may have a toxic component, possibly related to the circulating monoclonal light chain.

Abstract: Background:Small deposits of amyloid are often found intheheartsofelderlypatients.However,extensivedepositionoftransthyretin-derivedamyloidfibrilsintheheart (senile systemic amyloidosis [SSA]) can cause heart failure. The clinical features of SSA that involve the heart are ill defined, and the condition may be overlooked as a cause of heart failure. We sought to better define the clinical,echocardiographic,andelectrocardiographicfeaturesofcardiacinvolvementinSSAandtocomparethem with the findings in patients with light chain–associated (AL) amyloidosis that affects the heart. Methods: Eighteen consecutive patients with SSA and heart failure evaluated at a tertiary referral center for the diagnosis and treatment of amyloidosis were compared with 18 randomly selected patients with AL amyloidosisthatinvolvedtheheart.Allpatientsunderwentacomplete clinical and biochemical evaluation. Echocardiogramsandelectrocardiogramswereinterpretedbyblinded investigators. Results:PatientswithSSAwereolderthanthosewithAL amyloidosis and were all male. Proteinuria (protein outputof1gper24hours)wascommoninALamyloidosis butwasnotpresentinSSA.Leftventricularwallthickness was greater in patients with SSA than those with AL amyloidosis,butdespitethickerwallsandolderage,theseverity of heart failure was less in the SSA group and the mediansurvivalwasmuchlonger(75vs11months;P=.003). Conclusions: Senile systemic amyloidosis is a disorder of elderly men and is characterized by amyloidosis clinically limited to the heart. In contrast to the rapid progression of heart failure in AL amyloidosis, SSA results in slowly progressive heart failure. The difference in survival, despite evidence of more myocardial disease in the senile group, suggests that heart failure in AL amyloidosis may have a toxic component, possibly related to the circulating monoclonal light chain. Arch Intern Med. 2005;165:1425-1429