**4. Non-surgical treatment**

Conservative management of restrictive cardiomyopathy resulting from structural myocardial alteration is limited. Diuretics are used to balance the signs of congestive heart failure, with narrow margin against low-cardiac output. Calcium channel blockers are contraindicated for negative inotropic effect, as well as beta-blockers (Griffiths, Hughes et al. 1982; Gertz, Falk et al. 1985; Gertz, Skinner et al. 1985). Administration of digoxin is risky because of its binding to amyloid fibrils and resulting toxic effects (Rubinow, Skinner et al. 1981). Implantation of permanent pacemaker may be necessitated for conduction disorders, with potential for alleviation of symptoms (Mathew, Olson et al. 1997).

Chemotherapy in AL amyloidosis, based on hematooncology strategy in treatment of multiple myeloma, includes administration of melphalan orally (with prednisone (Skinner, Anderson et al. 1996)) or in dose-intensive intravenous protocol, followed by autologous blood stem cell transplantation (Comenzo, Vosburgh et al. 1998; Moreau, Leblond et al. 1998). The rationale is to reduce or abolish the supply of amyloidogenic monoclonal light chain protein from the plasma cell clone which may facilitate the regression of plasma deposits and improve the quality of life. Alternatively, thalidomide with dexamethasone, or bortezomib may be administered (Charaf, Iskandar et al. 2009). In selected patients, the combined chemotherapy and stem cell transplantation may prolong the survival, however, it carries the risk of increased morbidity and mortality (Saba, Sutton et al. 1999).
