In light-chain (AL) amyloidosis, prognosis is dictated by cardiac dysfunction. N-terminal natriuretic peptide type B (NT-proBNP) and cardiac troponins (cTn) are used to assess the severity of cardiac damage. We evaluated the prognostic relevance of a high-sensitivity (hs) cTnT assay, NT-proBNP, and cardiac troponin I in 171 consecutive patients with AL amyloidosis at presentation and 6 months after treatment. Response and progression of NT-proBNP were defined as more than 30% and more than 300 ng/L changes. All 3 markers predicted survival, but the best multivariable model included hs-cTnT. The hs-cTnT prognostic cutoff was 77 ng/L (median survival 10.6 months for patients with hs-cTnT above the cutoff). After treatment, response and progression of NT-proBNP and a more than 75% increase of hs-cTnT were independent prognostic determinant. In AL amyloidosis, hs-cTnT is the best baseline prognostic marker. Therapy should be aimed at preventing progression of cardiac biomarkers, whereas NT-proBNP response confers an additional survival benefit.