title: Prognostic value of N-terminal pro-brain natriuretic Peptide in outpatients with hypertrophic cardiomyopathy.
abstract: In hypertrophic cardiomyopathy, the plasma levels of N-terminal pro-brain natriuretic peptide (NT-proBNP) correlate with functional capacity. However, their prognostic relevance remains unresolved. We followed up 183 stable outpatients with hypertrophic cardiomyopathy (age 50 ± 17 years, 64% men) for 3.9 ± 2.8 years after NT-proBNP measurement. The primary end point included cardiovascular death, heart transplantation, resuscitated cardiac arrest, and appropriate implantable cardioverter-defibrillator intervention. The secondary end point (SE) included heart failure-related death or hospitalization, progression to end-stage disease, and stroke. The median NT-proBNP level was 615 pg/ml (intertertile range 310 to 1,025). The incidence of the primary end point in the lower, middle, and upper tertiles was 0%, 1.3%, and 2.1% annually, respectively (overall p = 0.01). On multivariate analysis, the only independent predictors of the primary end point were NT-proBNP (hazard ratio for log-transformed values 5.8, 95% confidence interval 1.07 to 31.6; p = 0.04) and a restrictive left ventricular filling pattern (hazard ratio 5.19, 95% confidence interval 1.3 to 21.9; p = 0.02). The NT-proBNP cutoff value of 810 pg/ml had the best sensitivity for the primary end point (88%), but the specificity was low (61%). The incidence of the SE in the lower, middle, and upper NT-proBNP tertiles was 4.6%, 12.0%, and 11.2% annually, respectively (overall p = 0.001). An NT-proBNP level of <310 pg/ml was associated with a 75% reduction in the rate of SE compared with a level of ≥310 pg/ml (hazard ratio 0.25, 95% confidence interval 0.11 to 0.57; p = 0.001), independent of age, left ventricular outflow tract obstruction, or atrial fibrillation. In conclusion, in stable outpatients with hypertrophic cardiomyopathy, plasma NT-proBNP proved a powerful independent predictor of death and heart failure-related events. Although the positive predictive accuracy of an elevated NT-proBNP level was modest, low values reflected true clinical stability, suggesting the possibility of avoiding or postponing aggressive treatment options.
authors.affiliation: Vita Salute University and San Raffaele Scientific Institute, Milan, Italy.
authors.forename: Rossella
authors.initials: R
authors.lastname: D'Amato
authors.forename: Benedetta
authors.initials: B
authors.lastname: Tomberli
authors.forename: Gabriele
authors.initials: G
authors.lastname: Castelli
authors.forename: Roberto
authors.initials: R
authors.lastname: Spoladore
authors.forename: Francesca
authors.initials: F
authors.lastname: Girolami
authors.forename: Alessandra
authors.initials: A
authors.lastname: Fornaro
authors.forename: Anna
authors.initials: A
authors.lastname: Caldini
authors.forename: Francesca
authors.initials: F
authors.lastname: Torricelli
authors.forename: Paolo
authors.initials: P
authors.lastname: Camici
authors.forename: Gian Franco
authors.initials: GF
authors.lastname: Gensini
authors.forename: Franco
authors.initials: F
authors.lastname: Cecchi
authors.forename: Iacopo
authors.initials: I
authors.lastname: Olivotto
mesh_terms: D015415:Biomarkers / Q000097:blood; D002312:Cardiomyopathy, Hypertrophic / Q000097:blood* / Q000401:mortality / Q000503:physiopathology; D004452:Echocardiography; D004562:Electrocardiography; D005260:Female; D006352:Heart Ventricles / Q000000981:diagnostic imaging / Q000503:physiopathology*; D006801:Humans; D007558:Italy / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D020097:Natriuretic Peptide, Brain / Q000097:blood*; D010045:Outpatients; D010446:Peptide Fragments / Q000097:blood*; D011379:Prognosis; D011498:Protein Precursors; D012189:Retrospective Studies; D013318:Stroke Volume; D015996:Survival Rate / Q000639:trends
chemical_list: D015415:Biomarkers; D010446:Peptide Fragments; D011498:Protein Precursors; C109794:pro-brain natriuretic peptide (1-76); D020097:Natriuretic Peptide, Brain