[The importance of cardiac bio-marker assay for the stratification and monitoring of AL amyloidosis patients -  single center experience].
BACKGROUND
Cardiac involvement is a dominant prognostic factor in AL amyloidosis patients. A detailed assessment of the presence and degree of cardiac involvement utilizes an array of noninvasive investigation methods, particularly echocardiography and MRI; laboratory parameters include troponins and natriuretic peptides. Cardiac involvement detection aside, cardiac bio-markers are used as a relatively strong stratification and prognostic factor.


OBJECTIVE
The presentation of cardiac bio-markers assay applications in AL amyloidosis patients at an individual treatment center.


METHODS
The monitored patient set consisted of 22 patients with histologically confirmed AL amyloidosis, of whom 18 met the criteria for cardiac involvement. Levels of cardiac bio-markers troponin T (TnT) and Nterminal probrain natriuretic peptide (NT ProBNP) were determined in all patients. Risk stratification of the patients utilized the Mayo staging system which is based on both bio-markers assays; Log Rank Test was applied to survival evaluation.


RESULTS
Median survival of patients with cardiac involvement stigmata was 10 months vs 60 months survival of patients without signs of cardiac involvement (p = 0.133). Of the 4 patients without cardiac involvement, 1 has shown positive levels of TnT and 2 positive levels of NT ProBNP. All cardiac involvement patients exhibited abnormal levels of NT ProBNP (median 4,752 ng/ l; 415.7- 35,000) as well as positive levels of TnT (median 0.0815 μg/ l; 0.02- 0.986). The application of the Mayo stratification system to the set had determined 2 patients at stage I, 5 patients at stage II and 15 patients at stage III. The median survival of the Mayo I + II group vs the Mayo III group was 60 vs 6 months (p = 0.015), revealing extremely limited survival of stage III patients. Assessment of TnT and NT ProBNP levels relative to treatment response shows that the degree of decrease in both markers depends on maximum treatment response -  respectively the attainment of a complete hematological remission.


CONCLUSIONS
The results, although obtained from a limited set of patients, confirm a definitive benefit of the application of cardiac bio-markers assay in the diagnostic and therapeutic algorithm of AL amyloidosis patients. The Mayo stratification system utilizing the cardiac indicator values represents a robust tool for risk stratification of AL amyloidosis patients.
T
T
Pika
P
P
Lochman
J
J
Vymětal
R
R
Metelka
P
P
Flodr
J
J
Minařík
P
P
Látalová
J
J
Zapletalová
J
J
Bačovský
V
V
Sčudla
D000328:Adult; D000368:Aged; D000682:Amyloid / Q000097:blood*; D000686:Amyloidosis / Q000145:classification / Q000175:diagnosis*; D015415:Biomarkers / Q000097:blood*; D009202:Cardiomyopathies / Q000097:blood* / Q000145:classification / Q000175:diagnosis*; D004452:Echocardiography; D005260:Female; D006801:Humans; D000075363:Immunoglobulin Light-chain Amyloidosis; D008297:Male; D020097:Natriuretic Peptide, Brain / Q000097:blood; D010446:Peptide Fragments / Q000097:blood; D011379:Prognosis; D020107:Troponin T / Q000097:blood
D000682:Amyloid; D015415:Biomarkers; D010446:Peptide Fragments; D020107:Troponin T; C035222:amyloid protein AL; C109794:pro-brain natriuretic peptide (1-76); D020097:Natriuretic Peptide, Brain