NPPB and primary systemic amyloidosis: The amyloidosis consensus statement defines cardiac involvement, in the presence of extracardiac biopsy-proven systemic amyloidosis, as the presence of a mean left ventricular (LV) end-diastolic wall thickness ≥ 12 mm on echocardiography in the absence of other possible causes, or an NT-proBNP > 332 pg/mL in the absence of atrial fibrillation or renal failure.