Bnp Measurement Pre- and Post-Noncardiac Surgery As Prognostic Factor of Cardiovascular Events in Hypertensive Patients

Introduction: Cardiovascular events in patients undergoing non-cardiac surgery are higher than other complications; they are associated with high levels of morbidity and mortality and represent the first cause of death post-surgery especially in hypertensive patients. This could be avoided identifying, before surgery, those patients at high risk for cardiac events. BNP is an optimal approach for cardiovascular pre-operatory risk stratification, and easy-to-use in this setting. Patients and Methods: 205 patients undergoing scheduled major non-cardiac surgery were recruited (M/F 91/114 mean age 64 yrs), and admitted in the general surgery department. We show only data of hypertensive patients (92 subjects). Preoperative data collection included: patient demographics, vital signs, routine blood samples including renal and hepatic function tests, plasma BNP level, 12-lead electrocardiogram. All clinical and biochemical data were examined by the consultant cardiologist and anesthetist for the evaluation of cardiovascular risk. A 30 days follow-up after discharge was made to investigate cardiovascular hospital re-admissions or death. Results: 92 out 205 (48 F and 44 M) (44,8%) studied patients were affected with hypertension (53 only hypertension, and 39 hypertension associated to other diseases); there was a significant difference (p < 0.005) between mean pre-surgery BNP values: 153.7 ± 359.1 pg/ml (median 42 pg/ml) vs mean post-surgery BNP: 271.6 ± 630.8 pg/ml (median 109 pg/ml). At 30 days follow-up 18/92 (19,5%) hypertensive patients had cardiovascular events (re-hospitalization, cardiological visit). Patients with events showed pre-surgery mean BNP levels: 476.5 ± 707 pg/ml (median 121.5 pg/ml) vs post-surgery mean BNP values: 690.8 ± 1131.6 pg/ml (median 356 pg/ml) without statistically significant difference (p = 0.06). Interestingly, patients with the higher degree of RCRI (III) had events in 43% of cases. Conclusions: BNP plays a relevant role in non-cardiac surgery hypertensive patients as prognostic factor for events at short term. Higher levels of BNP in these hypertensive patients who develop cardiovascular adverse outcomes at short term demonstrate the potential utility of this marker for a more accurate cardiological evaluation in subjects undergoing non-cardiac surgery.