Clinical characteristics of heart disease patients with a good prognosis in spite of markedly increased plasma levels of type-B natriuretic peptide (BNP): anomalous behavior of plasma BNP in hypertrophic cardiomyopathy.
BACKGROUND
Although it is not rare to encounter patients with plasma B-type natriuretic peptide (BNP) levels unequivalent to the severity of heart failure (HF), there has been little investigation to clarify the causative background of this phenomenon.


RESULTS
Among the 1,838 outpatients whose plasma BNP was measured, persistently increased levels of BNP above 500 pg/ml was observed for more than 6 months in 14 subjects with few HF symptoms. Among these, all of 4 patients without any following cardiac events (E-/high) for 12 months showed hypertrophic nonobstructive cardiomyopathy (HNCM). When we compared the clinical parameters of these patients with those of 22 HNCM patients without any following cardiac events whose plasma BNP levels were less than 200 pg/ml, there were only 2 clinical characteristics to be distinguished: (i) plasma renin activity (PRA) and norepinephrine (NE) levels were low in spite of markedly increased levels of plasma BNP in E-/high HNCM; and (ii) echocardiographic investigation revealed that only global left atrial fractional shortening was significantly lower in E-/high HNCM.


CONCLUSIONS
Plasma BNP levels do not always reflect the severity of HF in HNCM. It might be considered to utilize other clinical parameters such as NE and PRA to recognize HF severity in such patients.
Takeuchi
Ichiro
I
Department of Internal Medicine & Cardiology, Kitasato University School of Medicine, Sagamihara, Japan. takeuchi@aqr.calmnet.ne.jp
Inomata
Takayuki
T
Nishii
Mototsugu
M
Koitabashi
Toshimi
T
Nakano
Hironari
H
Shinagawa
Hisahito
H
Takehana
Hitoshi
H
Izumi
Tohru
T
D000368:Aged; D015415:Biomarkers / Q000097:blood; D002312:Cardiomyopathy, Hypertrophic / Q000097:blood / Q000175:diagnosis*; D004562:Electrocardiography; D005260:Female; D006331:Heart Diseases / Q000097:blood / Q000175:diagnosis*; D006801:Humans; D008297:Male; D008875:Middle Aged; D020097:Natriuretic Peptide, Brain / Q000097:blood*; D009638:Norepinephrine / Q000097:blood; D011379:Prognosis; D012083:Renin / Q000097:blood; D012720:Severity of Illness Index
D015415:Biomarkers; D020097:Natriuretic Peptide, Brain; D012083:Renin; D009638:Norepinephrine