N-terminal-proB natriuretic peptide in patients with stable coronary artery disease evaluated for ischemia with myocardial perfusion imaging.

BACKGROUND: Natriuretic peptides have emerged in the last years as useful diagnostic and prognostic biomarkers in patients with stable CAD. Myocardial ischemia per se might increase NT-proBNP levels.

OBJECTIVES: The aim of the present study was to determine whether NT-proBNP levels in patients with stable CAD and preserved left ventricular function are elevated and second, to compare NT-proBNP in patients with verified ischemia on myocardial perfusion imaging (MPI) to non-ischemic subjects with known CAD.

METHODS: 117 patients were prospectively included, divided in two groups: group A (26 patients)--with normal MPI and without known CAD and group B (91 patients)--with abnormal MPI or known CAD. Patients from group B were further divided according to the presence of ischemia on MPI in non-ischemic (29 pts) and ischemic (62 pts) subgroup.

RESULTS: Levels of NT-proBNP in group B were significantly higher compared to group A (median 53 vs 21 pg/ ml, p = 0.012). End diastolic and end systolic volumes were higher, and ejection fraction after stress and at rest was lower in group B (63% vs 71%, p = 0.0004 and 69% vs 75%, p = 0.008). No significant difference in NT-pro BNP levels (median 48 vs 62 pg/ml, p = 0.5) and functional parameters between the ischemic and nonischemic subjects was found.

CONCLUSION: Our data show that patients with stable coronary artery disease and preserved left ventricular function have elevated levels of NT-proBNP. We could not demonstrate that the presence of myocardial ischemia per se was an additional factor leading to increase of the natriuretic propeptide (Tab. 4, Ref. 12).