Introduction: Amyloidosis is a disease caused by infiltration of tissues by an amyloid protein. The most frequent cardiac amyloidosis are light chain (AL) amyloidosis, hereditary transthyretin (TTR-h) and wild transthyretin (w-TTR).
Objective: Describe baseline clinical, biological, echocardiographic characteristics and prognostic of patients referred for cardiac amyloidosis in the Amyloidosis expert cente.
Methods: From 2010 to July 2016, all patients referred to the expert center of our Hospital for suspected cardiac amyloidosis were included. Baseline demographic, clinical, laboratory and ultrasound characteristics were recorded and patients were followed-up for major events including death, cardiac transplantation and left ventricular assistance implant.
Results: Of the 942 patients referred for suspicion of CA, 502 had confirmed CA of whom162 had AL amyloidosis, 203 h-TTR and 141 w-TTR. CA were men in 60%, the median age was 69 years w-TTR amyloidosis were older (83 [79; 87], p<0.001) and more men (86%, p<0.001) than the two other types of CA. NYHA III-IV dyspnea was more frequent in AL amyloidosis (60%) and w-TTR (54%, p<0.001)compared to h-TTR, while neurological symptoms were more predominant in h-TTR (62% p<0.001). Creatinine, NT-proBNP and troponin were higher in AL amyloidosis and w-TTR (p<0.001) than in h-TTR. w-TTR amyloidosis had thicker Interventricular septum thicker, lower LVEF, higher global strain E/A and E/Ea ratios than the two other types of CA (p<0.001). During follow-up 137 major events occured. Median follow-up was 22 (8–36) months. The survival without major event was 59% for AL amyloidosis, 79% for w-TTR, 81% for h-TTR versus 88% for patients without amyloidosis (p<0.001). In multivariate analysis, only NYHA class III-IV, hyponatremia, elevation of creatinine, troponin and NTproBNP were independent prognostic factors (p<0.001).
Conclusion: Cardiac amyloidosis is more frequent than initially thought, with very different layouts depending on the type of amyloid protein involved. Its prognosis is poor at short term. The challenge is to achieve earlier diagnosis to improve prognosis