The prognostic value of midregional proatrial natriuretic peptide in patients with hemorrhagic stroke.
BACKGROUND
Atrial natriuretic peptide (ANP) is a well-known prognostic marker of outcome and mortality in patients with cardiovascular disease. Midregional proatrial natriuretic peptide (MR-proANP) is a stable fragment of the ANP precursor hormone. As a prognostic marker after ischemic stroke, it reliably predicts poststroke mortality and functional outcome. This study aimed to analyze the prognostic value of MR-proANP in patients with hemorrhagic stroke, i.e. subarachnoid (SAH) and intracerebral hemorrhage (ICH).


METHODS
MR-proANP was analyzed in patients with spontaneous SAH or spontaneous ICH. All patients were prospectively randomized into two treatment arms: (1) a prophylactic normothermia group with a target core temperature 36.5°C using endovascular cooling, and (2) a control group with conventional stepwise predefined fever management using antipyretic medication and surface cooling. Blood samples were obtained on admission and on days 4 and 7. Measurement of MR-proANP was performed in serum using sandwich immunoassay. The primary endpoint was functional outcome [assessed by the Glasgow Outcome Score (GOS)] and the secondary endpoints were mortality within 180 days after hemorrhagic stroke and influence of temperature on MR-proANP. A favorable outcome was defined as GOS 4-5, and the patients were considered to have a poor outcome with a 180-day GOS score between 1 and 3.


RESULTS
Analysis of MR-proANP was performed in 24 patients with spontaneous SAH and 22 patients with spontaneous ICH. MR-proANP was elevated on days 4 and 7 as compared to baseline levels (p < 0.05 and p < 0.001, respectively). High MR-proANP levels (>120 pmol/l) were associated with increased mortality and poor outcome (after 180 days; p < 0.05, respectively). There was no significant difference regarding MR-proANP serum concentrations between the endovascular and the control groups.


CONCLUSIONS
Increased levels of MR-proANP are independently associated with poor functional outcome and increased mortality after 180 days in patients with hemorrhagic stroke. Endovascular temperature control had no significant influence on MR-proANP levels.
Department of Neurology, Innsbruck Medical University, Innsbruck, Austria.
Marlene
M
Fischer
Mira
M
Katan
Nils G
NG
Morgenthaler
Marleen
M
Seiler
Beat
B
Müller
Peter
P
Lackner
Mario
M
Errath
Raimund
R
Helbok
Bettina
B
Pfausler
Ronny
R
Beer
Erich
E
Schmutzhard
Gregor
G
Broessner
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D009320:Atrial Natriuretic Factor / Q000097:blood*; D015415:Biomarkers / Q000097:blood; D005260:Female; D006801:Humans; D020300:Intracranial Hemorrhages / Q000097:blood / Q000401:mortality / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D011379:Prognosis; D011446:Prospective Studies; D020127:Recovery of Function; D020521:Stroke / Q000097:blood / Q000401:mortality / Q000503:physiopathology*
D015415:Biomarkers; D009320:Atrial Natriuretic Factor