Elevated B-type natriuretic peptide blood levels during hypertensive crisis: A novel diagnostic marker of acute coronary and cerebrovascular events?

Objectives: The objectives of this study were: (i) to assess the role of B-type natriuretic peptide (BNP) in the course of hypertensive crisis; (ii) to evaluate the possible role of BNP in the differential diagnosis between hypertensive emergencies (HE) or urgencies (HU); and (iii) to investigate the relationship between BNP concentration and blood pressure (BP) acute burden with consequent myocardial ischaemia or brain damage. Methods: 57 consecutive patients were admitted to the emergency department for acute elevated BP levels (systolic BP [SBP]/diastolic BP [DBP]: 200.7 ± 24.7/121.2 ± 12.4 mmHg) were enrolled. On the basis of clinical data, patients were subdivided into two groups: (i) 25 patients with HE: SBP/DBP 204.16 ± 29.1/123.3 ± 13.0 mmHg with heart (acute coronary syndrome) or brain involvement; (ii) 32 patients with HU: SBP/DBP 198.1 ± 20.7/120 ± 11.7 mmHg, without any acute or ongoing deterioration of target organs. For each patient, a serum dosage of BNP was performed. Results: In the whole population, no significant relationship was found between BP total burden and BNP level. In HE, BNP concentration (113.22 ± 87 pg/mL) was significantly (p < 0.001) higher than in HU (23.5 ± 21.3 pg/ mL) patients. There was a significant increase (p < 0.01) of BNP blood level in HE patients with acute coronary syndrome (162.02 ± 95.7 pg/mL) compared with those with neurological complications (80.7 ± 65.2 pg/mL). Moreover, in HU patients, there was a significant relationship (r = 0.37; p < 0.05) between BNP levels and pulse pressure. Conclusions: During hypertensive crisis, BNP blood level increase seems to have a role as a diagnostic tool for the screening of hypertensive emergencies due to an acute coronary or brain injury, and the BNP elevation is greater in the presence of myocardial ischaemia than brain damage.