Preoperative Brain Natriuretic Peptide Levels Research Articles

Moždani natriuretski peptid kao prediktor kliničkog ishoda i poboljšanja simptoma nakon ugradnje uređaja za trajnu mehaničku cirkulatornu potporu

Introduction: The predictive value of brain natriuretic peptide in heart failure is well-known, but its importance as an outcome predictor after a left ventricular assist device ( LVAD ) implantation remains unaddressed. This research aims to examine the significance of brain natriuretic peptide (BNP) as an indicator of treatment outcomes during different post-implantation periods. Methods: A retrospective cohort study included the analysis of medical records of 87 patients in whom LVAD was implanted at the University Clinical Center of Serbia in the period 2014-2020. The correlation of BNP levels with treatment outcomes after operation was evaluated. Results: The average preoperative BNP for all patients was 1244 pg/ mL. The average ejection fraction (EF) was 15% (median), endsystolic diameter (ESD) was 6.80 cm and endiastolic diameter (EDD) was 7.70 cm. Eighty-one patients were NYHA class 4, and 6 patients were NYHA 3. Compared to the preoperative BNP level below or above 1000 pg/mL, there was no significant difference in overall survival of patients after operation (Log Rank [Mantel-Cox] test, p=0.838). BNP levels postoperatively decreased from 358 pg/mL at 3 months upon surgery to 136 pg/mL 5 years upon surgery (Friedman test, p<0.001). BNP levels show strong negative correlation with EF (decrease in BNP level and increase in EF value), and strongly positive correlation with EDD, ESD, and NYHA class (a decrease in BNP and a decrease in EDD, ESD, and NYHA). Conclusion: Preoperative BNP level may not be an adequate predictor of the outcome after LVAD implantation, but the post-implantation decrease in BNP levels is highly correlated with parameters that indicate an improvement in the clinical status and positive changes in the myocardium and long-term survival.

The effect of type of anesthesia (general versus spinal) on postoperative levels of brain natriuretic peptide in parturient women with cardiovascular diseases undergoing cesarean section and related cardiac impacts

ABSTRACT Background Dealing with parturient women with cardiac disease is still a challenge for anesthesiologists due to the presence of physiologic burden of pregnancy in addition to the already existing compromised cardiovascular system. A variety of cardiac indices have been utilized to forecast the risk of perioperative cardiac complications, yet limitations in their predictive value exist. Perioperative brain natriuretic peptide (BNP) level is used as a prognosticator of cardiac complications following surgery in cardiac and non-cardiac individuals. Aim of study To compare the effect of general and spinal anesthesia during cesarean section in parturient with cardiac disease on BNP levels and on predicting adverse cardiac events. Methods Thirty cardiac parturient with cesarean section were assigned randomly into two groups of equal size. Group A: participants received general anesthesia (GA); Group B: participants received spinal anesthesia. Preoperative and 2 and 24 h postoperative BNP levels were measured. Intraoperative and 24 h postoperative cardiac complications were observed. Results Preoperative and 2 and 24 h postoperative BNP mean levels were similar in the two groups. In each group, the 2 and 24 h postoperative rise in BNP mean levels was insignificant compared to the preoperative mean levels of BNP. Incidence of complications was comparable in both groups, but it was associated with the already high preoperative levels of BNP. Conclusions The study concludes that safely conducted certain type of anesthesia has no effect on the perioperative BNP levels nor incidence of complications which is associated with the already high preoperative BNP levels.

Ninety-day mortality of extremely elderly patients undergoing hip fracture surgery and its association with preoperative cardiac function: a single-center retrospective study.

We investigated the 90-day mortality rate in elderly patients who underwent hip fracture surgery and the association of preoperative cardiac function with mortality. We retrospectively enrolled 133 consecutive patients aged 80years or older who underwent hip fracture surgery. We obtained information for patient sex, age, comorbidities, medications, anesthesia method, left ventricular systolic and diastolic functions assessed by echocardiography, and preoperative brain natriuretic peptide (BNP) levels. Multivariate logistic regression analysis was performed. The 90-day mortality rate in patients with a mean age of 88.9years was 7.5% (10/133). More than half of the patients had diastolic dysfunction of the left ventricle. There were no significant differences in preoperative cardiac systolic and diastolic functions between the mortality group and non-mortality group. The preoperative BNP level in the mortality group was significantly higher than that in the non-mortality group (p = 0.038). Preoperative BNP level was not an independent risk factor for 90-day mortality (p = 0.081) in the primary multivariate logistic regression analysis but was an independent risk factor (p = 0.039) with an odds ratio of 1.004 (95% CI 1.000-1.008) in the sensitivity analysis with different explanatory variables. The 90-day mortality rate in patients over 80years old after hip fracture surgery was 7.5%. There were no significant differences in preoperative cardiac function assessed by echocardiography between the mortality and non-mortality groups. Our results suggest that there is no association or only a weak association of high BNP level with 90-day mortality in this age population.

Combining Prognostic Nutritional Index and Brain Natriuretic Peptide as a Predicting Tool for Heart Transplantation.

Our study aimed to evaluate the potential of prognostic nutritional index (PNI) and Brain natriuretic peptide (BNP) in predicting the prognosis of heart transplantation (HTx). We retrospectively investigated 489 patients undergoing HTx between 2015 and 2020 in our center. The relationship between preoperative index and prognosis was analyzed respectively, the optimal cut-off values for preoperative PNI and BNP level were evaluated with receiver operating curve analysis. Uni-variate analysis and multivariate analysis were used to compare baseline data (sex, age, diagnosis, etc.) of groups divided by the level of PNI and BNP. Propensity score matching (PSM) was applied to eliminate bias. We calculated the C-index from the prediction efficiency of PNI and BNP. During the period, 489 recipients undergoing HTx in our center were included according to the inclusion criteria; 383 (78.3%) males and 106 (21.7%) females were included in this study, with a median age of 47.57 years old. The ROC curve showed that the optimal cut-off values of each indicator were verified as 49.345 for PNI, and 4397.500 for BNP. The multivariate analyses indicated that PNI (p = 0.047), BNP (p = 0.024), age (p = 0.0023), and waiting time (p = 0.012) were risk factors for all-cause death after HTx. Propensity score matching generated 116 pairs based on PNI level and 126 pairs based on BNP level, and the results showed that OS (overall survival) was significantly correlated with PNI (n = 232, p = 0.0113) and BNP (n = 252, p = 0.0146). Our study implied that higher PNI and lower BNP level had direct correlation with better survival after HTx. Combining PNI and BNP together would be a potential clinical preoperative instrument to predict the survival of patients after HTx, especially in short-term survival.

Mid-Term Results of Totally Thoracoscopic Ablation in Patients with Recurrent Atrial Fibrillation after Catheter Ablation.

BackgroundWe investigated the impact of previous catheter ablation (CA) on the midterm outcomes of totally thoracoscopic ablation in patients with lone atrial fibrillation (AF).MethodsBetween February 2012 and July 2018, 332 patients underwent totally thoracoscopic ablation for the treatment of AF (persistent AF; n=264, 80%). The patients were stratified into CA (n=47, 14%) and non-CA (nCA; n=285, 86%) groups according to their CA history.ResultsAll the baseline clinical characteristics and risk factors were similar between the groups except for age, percentage of male patients, prevalence of paroxysmal AF, prior percutaneous coronary intervention, and left atrial volume index (LAVI). No significant intergroup differences were observed in the incidence of early and late complications. At late follow-up, normal sinus rhythm was observed in 92% (43 of 47) of the patients in the CA group and 85% (242 of 285) of the patients in the nCA group (p=0.268). The rate of freedom from AF recurrence at 5 years was 55.3%±11.0% in the CA group, which was similar to that in the nCA group (55.7%±5.1%, p=0.690). In Cox regression analysis, preoperative brain natriuretic peptide levels and LAVI were associated with AF recurrence, but CA history was not significant.ConclusionTotally thoracoscopic ablation was safe and effective in treating AF irrespective of CA history. A history of CA did not appear to affect the procedural complexity.

Risk factors of atrial fibrillation occurring after radical surgery of esophageal carcinoma

BackgroundAtrial fibrillation (AF) is a common complication after radical surgery of esophageal cancer. The aim of this study was to explore AF risk factors after radical surgery of esophageal carcinoma.MethodThe data of 335 patients with esophageal cancer who were admitted in our hospital from January 2014 to August 2016 for the first time were retrospectively analyzed. We retrieved the papers in some data banks using the search terms including English and Chinese search terms, and obtained 13 factors which were mentioned in more than 6 papers. The 13 factors including age, gender, history of smoking, history of hypertension, history of peripheral vascular disease, history of cardiac stents or angina pectoris, preoperative pulmonary infection, preoperative brain natriuretic peptide (BNP) level, preoperative left ventricular diastolic dysfunction, operative method, lesion location, intraoperative blood transfusion, adhesion between lymph nodes and pericardium, underwent univariate and multivariate analyses.ResultsOf the 335 patients with esophageal cancer, 48 had AF within one week after operation. Univariate analysis indicated that the age (OR: 4.89; CI: 2.53–9.47, P: 0.000), gender (OR: 2.26; CI: 1.17–4.37, P: 0.013), history of peripheral vascular disease (OR: 2.29; CI: 1.06–4.92, P: 0.030), history of cardiac stents or angina pectoris (OR: 27.30; CI: 12.44–59.91, P: 0.000), preoperative BNP level (OR: 27.13; CI: 10.97–67.06, P: 0.000), preoperative left ventricular diastolic dysfunction (OR: 2.22; CI: 1.19–4.14, P: 0.012), operative method (OR: 2.09; CI: 1.002–4.380, P: 0.046), intraoperative blood transfusion (OR: 20.24; CI: 8.39–48.82, P: 0.000), and adhesion between lymph nodes and pericardium were risk factors (OR: 2.05; CI: 1.08–3.87, P: 0.024). Furthermore, multivariate analysis displayed that advanced age (OR: 5.044; CI: 1.748–14.554, P: 0.003), male (OR: 6.161; CI: 2.143–17.715, P: 0.001), history of cardiac stents or angina pectoris (OR: 48.813; CI: 13.674–174.246, P: 0.000), preoperative BNP > 100 (OR: 41.515; CI: 9.380–183.732, P: 0.000), open surgery (OR: 3.357; CI: 1.026–10.983, P: 0.045), intraoperative blood transfusion (OR: 58.404; CI: 10.777–316.509, P: 0.000), and adhesion between lymph nodes and pericardium (OR: 3.954; CI: 1.364–11.459, P: 0.011) were risk factors which could increase the incidence of postoperative AF.ConclusionWe should pay attention to the above risk factors in order to reduce the incidence of postoperative AF.

Preoperative Echocardiographic Indices of Diastolic Dysfunction and Brain Natriuretic Peptide in Predicting Postoperative Atrial Fibrillation After Noncardiac Surgery.

We have shown previously that either echocardiographic indices of diastolic dysfunction or increased preoperative brain natriuretic peptide (BNP) predict postoperative atrial fibrillation (POAF). Because these 2 predictors of POAF have not been evaluated together, our goal was to further elucidate their concurrent role in patients undergoing noncardiac thoracic surgery. We retrospectively identified 191 patients who had a preoperative transthoracic echocardiogram and serum BNP level collected as part of routine care before major lung or esophageal resection. Clinical and echocardiographic data were compared between patients who did or did not develop POAF (>5 minutes), and prognostic factors for POAF were identified. Univariate associations with POAF (41 of 191; 22% patients) included older age (P = .04), male sex (P = .01), hypertension (P = .03), increased body mass index (P = .01), and prolonged transmitral flow deceleration time (P < .0001), whereas BNP was not statistically significant (P = .07). Stepwise logistic regression analysis showed that both increasing transmitral flow deceleration time (continuous data log base 2 transformed; odds ratio, 16.05; 95% confidence interval, 3.74-68.96; P = .0002) and left atrial diastolic volume index (continuous data log base 2 transformed; odds ratio, 3.29; 95% confidence interval, 1.22-8.91; P = .02) were independent risk factors of POAF (area under the receiver operating characteristic curve = 0.73). There was no significant interaction between BNP and the 2 independent variables (P = .60, and P = .90), respectively. In a cohort of patients who had echocardiography and BNP measurements before undergoing major thoracic surgery, this study showed that when evaluated together greater preoperative left atrial diastolic volume index and transmitral flow deceleration time but not BNP levels were independent predictors for POAF.

Perioperative Brain Natriuretic Peptide in Pediatric Cardiac Surgery Patients: Its Association With Postoperative Outcomes

The aim of this study was to investigate the relationship between perioperative brain natriuretic peptide levels and the incidence of postoperative serious adverse events (SAEs) in pediatric cardiac patients. A prospective observational study. A single-institution university hospital. Children under 15 years old who underwent cardiac surgery that required cardiopulmonary bypass from December 21, 2012 to February 26, 2014. The Risk Adjustment for Congenital Heart Surgery 1 category less than 1 was excluded. Brain natriuretic peptide (BNP) levels were measured preoperatively (BNPpre) and on postoperative day 1 (BNPPOD1) and postoperative day 3 (BNPPOD3). Primary outcome was the incidence of postoperative SAEs; (1) death in the intensive care unit, (2) requirement of extracorporeal membrane oxygenation, (3) cardiac arrest, and (4) requirement of reoperation for hemodynamic instability. The authors included 71 patients in this study. There were 8 patients (11%) who had at least 1 SAE. Median preoperative BNP level in patients with SAEs was significantly higher than in those without SAEs (1,541 pg/mL [IQR: 121-5,962] v 122 pg/mL [QR: 34-342], p = 0.01). From the receiver operating characteristic curve of BNPpre for the incidence of SAEs, an area under the curve was 0.77 (95%CI 0.55-0.91). The best cutoff BNPpre number was 1,000 pg/mL. From the multivariate logistic regression model, BNPpre>1,000 pg/mL was associated independently with risk of SAEs (adjusted odds ratio = 8.5, 95% CI [1.3, 59.3], p = 0.02). In conclusion, the authors' study showed that increased preoperative brain natriuretic peptide concentration, especially a concentration of more than 1,000 pg/mL, was associated with risk of SAEs in pediatric cardiac surgery patients.

Factors associated with postoperative requirement of renal replacement therapy following off-pump coronary bypass surgery

Cardiopulmonary bypass usage provokes a systemic inflammatory response resulting in deterioration of renal function. However, risk factors for requiring renal replacement therapy (RRT) following off-pump coronary artery bypass graft surgery (CABG) have not yet been fully elucidated. We reviewed 718 consecutive patients undergoing elective off-pump CABG at our institution, excluding patients on chronic hemodialysis preoperatively. Sub-analysis of patients with preserved renal function, defined as a creatinine level below a cut-off value of 1.12mg/dL (obtained by receiver operating characteristic curve), was also performed. Of the 718 patients, 41 (5.7%) required RRT. There were 556 patients (77.4%) with preserved renal function preoperatively, and 13 (2.4%) of these required postoperative RRT. Multivariate analysis revealed that age (years) and preoperative serum creatinine (mg/dL) and brain natriuretic peptide (BNP) levels (pg/dL) were associated with RRT [odds ratios (OR) 1.052, 95% confidence interval (CI) 9.064 and 1.001, respectively, all p<0.05] in the total population, whereas low albumin concentration was the only independent predictor for RRT in patients with preserved renal function (OR 0.062, p<0.0001). When creatinine levels were below 1.5mg/dL, the predictive power of hypoalbuminemia for RRT requirement overwhelmed that of creatinine or BNP levels. Older age, preoperative elevated creatinine and BNP levels were associated with a requirement for RRT following off-pump CABG. In patients with preserved renal function, hypoalbuminemia was most significantly related to the RRT requirement.

Plasma BNP level combined with surgical Apgar score to predict operative major cardiac adverse events in malignant obstructive jaundice patients.

Objective:To investigate the predictive effect of major adverse cardiac events (MACE) in malignant obstructive jaundice (OJ) patients using plasma brain natriuretic peptide (BNP) level and surgical Apgar scoring (SAS) system.Methods:Forty one malignant OJ patients undergoing surgical treatments were studied at a single center. Pre-and postoperative plasma BNP level, total bilirubin (TBil) and data of cardiac function (HR, CVP, CI, LVEF%) were detected, the SAS was calculated during the surgery, the relationship of both plasma BNP level and SAS with MACE after surgery was analyzed.Results:Thirteen patients out of 41 (31.71%) experienced MACE without cardiac death. OJ patients had a higher plasma BNP level than baseline before operation (191.61±105.76 pg/ml VS 175 pg/ml, P<0.05), the cardiac function data was improved (CVP: t=4.761, p=0.000; CI: t=3.539, p=0.001; LVEF%: t=3.632, p=0.001) after the operation. Patients with lower SAS had increasing incidence of MACE after surgery.Conclusion:Malignant OJ patients with higher preoperative BNP level and lower surgical Apgar score were identified at high risk of MACE after surgery.

Relationship of pre-operative serum brain natriuretic peptide with risk of acute kidney injury after cardiac surgery

Objective To observe the relationship of pre-operative serum brain natriuretic peptide(BNP) with risk of acute kidney injury(AKI) after cardiac surgery.Methods We collected 182 patients undergoing cardiac surgery at Department of Cardiac Surgery,Changhai Hospital from Jan.2012 to Jan.2013.The surgical procedures included coronary artery bypass graft(CABG),valve replacement,and combined surgery(CABG + valve replacement).According to the preoperative BNP levels,the patients were divided into five groups in an ascending order.The definition and classification weres accorded to the latest AKI KDIGO(Kidney Disease:Improving Global Outcomes) guideline; the AKI incidence was obtained from patients with different BNP levels.Receiver operating characteristic(ROC) curves were used to evaluate the value of BNP level as a predictor of AKI.Results The average age of the 182 patients was(68.6 ± 8.9) years old,with male being 65.9%(120 /182).The surgery procedures including 82 CABG(45.0%),57 valve replacement(31.3%),and 43 combined surgery(CABG + valve replacement)(23.6%).We found that age,basic renal function and pre-operative BNP levels were significantly different between the five BNP groups(P 0.05).The incidence of AKI was33.5%(61 /182) in this study.The incidence rates of stage 1 AKI and total AKI significantly increased with increase of BNP levels in the five BNP groups(P 0.05).As a predictor of AKI ROC curves,BNP area under the curve(AUC) was 0.687(95% CI: 0.607-0.768).Conclusion Pre-operative BNP level is associated with post-operative AKI in high risk patients undergoing cardiac surgery,and it is a potential predictor of AKI risk stratification after cardiac surgery.

Serum Brain Natriuretic Peptide and Risk of Acute Kidney Injury After Cardiac Operations in Children

Acute kidney injury (AKI) after pediatric cardiac operations is associated with poor outcomes and is difficult to predict. We conducted a prospective study to evaluate whether preoperative brain natriuretic peptide (BNP) levels predict postoperative AKI among children undergoing cardiac operations. This was a three-center, prospective study (2007-2009) of 277 children undergoing cardiac operations (n= 121, aged <2 years) with available preoperative BNP values. Preoperative BNP was measured and categorized into tertiles. The performance of BNP was evaluated alone and in combination with clinical factors. AKI was defined as doubling of serum creatinine or need for acute dialysis. Postoperative AKI occurred in 165 children (60%), with 118 cases (43%) being mild and 47 cases (17%) severe. Preoperative BNP was not associated with increased risk of mild or severe postoperative AKI and did not significantly improve AKI risk prediction when added to clinical models. Preoperative BNP was, however, associated with several clinical outcomes, including length of stay and mechanical ventilation. The results were similar when the analysis was repeated in the subset of children younger than 2 years of age or when the association of postoperative BNP and AKI was evaluated. Preoperative BNP levels did not predict postoperative AKI in this cohort of children undergoing cardiac operations. Both preoperative and postoperative BNP levels are associated with postoperative outcomes. Clinical Trial Registration at Clinicaltrials.gov as NCT00774137.

Prediction of early postoperative major cardiac events after elective orthopedic surgery: the role of B-type natriuretic peptide, the revised cardiac risk index, and ASA class

BackgroundThe aim of this study was to evaluate pre- and post-operative brain natriuretic peptide (BNP) levels and compare the power of this test in predicting in-hospital major adverse cardiac events (MACE: atrial fibrillation, flutter, acute heart failure or non-fatal/fatal myocardial infarction) in patients undergoing elective prosthesis orthopedic surgery to that of the Revised Cardiac Risk Index (RCRI) and American Society of Anesthesiology (ASA) class, the most useful scores identified to date.MethodsThe study was an observational study of consecutive patients undergoing elective prosthesis orthopedic surgery. Surgical risk was established using RCRI score and ASA class criteria. Venous blood was sampled before surgery and on postoperative day 1 for the measurement of BNP. The intraoperative data collected included details of the surgery and anesthesia and any MACE experienced up until hospital discharge.ResultsMACE occurred in 14 of the 227 patients treated (6.2%). Age was statistical associated with MACE (p < 0.004). Preoperative BNP levels were higher (p < 0.0007) in patients who experienced MACE than in event-free patients (median values: 92 and 35 pg/mL, respectively). Postoperative BNP levels were also greater (p < 0.0001) in patients sustaining MACE than in event-free patients (median values: 165 and 45 pg/mL, respectively). ROC curve analysis demonstrated that for a cut-off point ≥ 39 pg/mL, the area under the curve for preoperative BNP was equal to 0.77, while a postoperative BNP cut-off point ≥ 69 pg/mL gave an AUC of 0.82.ConclusionsBoth pre- and post-operative BNP concentrations are predictors of MACE in patients undergoing elective prosthesis orthopedic surgery.

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Application of preoperative brain natriuretic peptide levels in clinical practice

The purpose of the study was to determine the clinical utility and practical application of preoperative brain natriuretic peptide (BNP) levels. This is a retrospective review of operating room procedures from November 2006 to March 2009. Preoperative history and physical were reviewed and BNP laboratory levels obtained prior to all procedures and the postoperative course reviewed for incidence of 30-day cardiac complications. A receiver operator curve analysis demonstrated that a preoperative BNP threshold ≥95.5 pg/mL correctly identified 75% of patients with cardiac complications and values ≤18.5 pg/mL identified 100% of patients without adverse postoperative cardiac complications. Multivariable analysis also revealed a history of peripheral arterial disease as the most significant preoperative predictor of cardiac complications followed by BNP above the threshold (odds ratio = 3.7), hypothyroidism, coronary artery disease and prior myocardial infarction. In conclusion, preoperative BNP levels are a useful adjunct in clinical practice to help identify those patients with a high postoperative risk and those with a minimal postoperative risk.

Brain natriuretic peptide and risk of atrial fibrillation after thoracic surgery

Postoperative atrial fibrillation (POAF) complicating general thoracic surgery is a marker of increased morbidity and stroke risk. Our goal was to determine whether increased preoperative brain natriuretic peptide (BNP) levels are able to stratify patients by the risk of POAF. Using a prospective database of 415 patients aged 60 years or older, who had undergone lung or esophageal surgery during a 1-year period, the preoperative clinical data, including BNP levels, were compared between patients who developed POAF lasting longer than 5 minutes during hospitalization and those who did not. POAF occurred in 65 (16%) of the 415 patients and was more frequent among patients who had undergone esophagectomy or anatomic lung resection (22% or 58 of 269) compared with those who did not (5% or 7 of 146; P < .0001). After esophagectomy or anatomic lung resection, 46 (34%) of the 135 patients with BNP levels greater than the median (≥ 30 pg/mL) developed POAF compared with only 12 (9%) of 134 patients with BNP levels less than 30 pg/mL (P < .0001). The rates of POAF in patients undergoing other thoracic procedures were low and not associated with the BNP levels. Multivariate logistic regression analysis showed that in patients undergoing esophagectomy or anatomic lung resection, older age (5-year increments, odds ratio [OR], 1.28; 95% confidence interval [CI], 1.01-1.61; P = .04), male gender (OR, 2.61; 95% CI, 1.12-4.17; P = .02), and BNP level 30 pg/mL or greater (OR, 4.52; 95% CI, 2.19-9.32; P < .0001) were independent risk factors for POAF. The length of hospital stay was significantly increased in patients who developed POAF compared with those who did not (P < .0001). Among patients undergoing anatomic lung resection or esophagectomy, increased age, male gender, and preoperative BNP level of 30 pg/mL or greater were significant risk factors for the development of POAF. The identification of patients who are more likely to develop POAF will allow the development of trials assessing prevention strategies aimed at reducing this complication.

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Preoperative Serum Brain Natriuretic Peptide and Risk of Acute Kidney Injury After Cardiac Surgery

Acute kidney injury (AKI) after cardiac surgery is associated with poor outcomes and is difficult to predict. We conducted a prospective study to evaluate whether preoperative brain natriuretic peptide (BNP) levels predict postoperative AKI among patients undergoing cardiac surgery. The Translational Research Investigating Biomarker Endpoints in Acute Kidney Injury (TRIBE-AKI) study enrolled 1139 adults undergoing cardiac surgery at 6 hospitals from 2007 to 2009 who were selected for high AKI risk. Preoperative BNP was categorized into quintiles. AKI was common with the use of Acute Kidney Injury Network definitions; at least mild AKI was a ≥0.3-mg/dL or 50% rise in creatinine (n=407, 36%), and severe AKI was either a doubling of creatinine or the requirement of acute renal replacement therapy (n=58, 5.1%). In analyses adjusted for preoperative characteristics, preoperative BNP was a strong and independent predictor of mild and severe AKI. Compared with the lowest BNP quintile, the highest quintile had significantly higher risk of at least mild AKI (risk ratio, 1.87; 95% confidence interval, 1.40-2.49) and severe AKI (risk ratio, 3.17; 95% confidence interval, 1.06-9.48). After adjustment for clinical predictors, the addition of BNP improved the area under the curve to predict at least mild AKI (0.67-0.69; P=0.02) and severe AKI (0.73-0.75; P=0.11). Compared with clinical parameters alone, BNP modestly improved risk prediction of AKI cases into lower and higher risk (continuous net reclassification index; at least mild AKI: risk ratio, 0.183; 95% confidence interval, 0.061-0.314; severe AKI: risk ratio, 0.231; 95% confidence interval, 0.067-0.506). Preoperative BNP level is associated with postoperative AKI in high-risk patients undergoing cardiac surgery. If confirmed in other types of patients and surgeries, preoperative BNP may be a valuable component of future efforts to improve preoperative risk stratification and discrimination among surgical candidates.

Preoperative Brain Natriuretic Peptide (BNP) Is a Better Predictor of Adverse Cardiac Events Compared to Preoperative Scoring System in Patients Who Underwent Abdominal Surgery

Cardiovascular disease is the leading cause of perioperative death in surgical patients. A variety of clinical scoring systems have been developed to predict adverse cardiovascular events. B-type natriuretic peptide (BNP) is a sensitive and specific predictor of left ventricular systolic dysfunction and predicts first cardiovascular event and death in the general population. We present a prospective, single-center, observational cohort study of patients undergoing major abdominal surgery and evaluate the role of BNP in predicting adverse cardiac events. A total of 205 patients were included in the study. All patients were assessed by a cardiological clinical evaluation, a 12-lead ECG report, and a preoperative and postoperative blood sample for plasmatic BNP assessment. The primary end point was the predictive power of preoperative BNP levels for adverse cardiac events until 30 days after discharge. Thirty-one of 205 (15%) patients had adverse cardiac events in the postoperative period up to 30 days after discharge. Five patients (2.4%) of these died of cardiac events. Preoperative BNP values were significantly increased in the 31 patients compared to the other patients in the postoperative period [mean = 112.93 pg/ml (range = 5-2,080) vs. 178.99 pg/ml (range = 5-3,980); median = 117 vs. 23 pg/ml; 95% CI = 49-181; p < 0.0001]. At logistic regression, a preoperative BNP value of >36 pg/ml was the only effective predictor of adverse cardiac events. We have demonstrated that elevated preoperative BNP levels are independent predictors of adverse cardiac events in a cohort of patients undergoing major abdominal surgery in a general surgery department, and this is the first study about this specific cohort of patients.

Role of Brain Natriuretic Peptide as a Prognostic Marker in Non-Cardiac Surgery

Refer to the page 20-24 The Brain Natriuretic Peptide; brain natriuretic peptide (BNP) and its inactive precursor N-terminal pro-BNP, are well-established risk markers in various acute and chronic cardiac conditions. However, their value as preoperative risk markers is unclear. BNP is secreted by cardiac myocytes in response to mechanical stretching caused by both pressure and volume overload. Myocardial damage or ventricular dysfunction (both systolic and diastolic) raises the plasma level of BNP. Even a transient myocardial ischemia owing to the demand and supply imbalance produces measurable change in plasma BNP levels. The perioperative period can result in a period of critical stress. Factors associated with surgery and anesthesia such as trauma, bleeding, intubation, hypoxia, hypothermia, pain and medications induce intense inflammation, hypercoagulability and sympathetic activation. All these factors trigger acute cardiac ischemia, arrhythmia and ventricular decompensation, which are associated with perioperative elevation of troponin, C-reactive protein and BNP. Interest in BNP as a preoperative risk marker has increased because the currently used preoperative clinical cardiac risk indices have only modest predictive power. It is inevitable since many surgical patients have underlying diseases, such as arthritis, cancer and diabetes mellitus, which limit physical activities to exhibit symptoms of existing cardiac disease. Although stress tests using imaging modalities can be recruited, BNP is a fair and easy alternative to get additive prognostic information. Recent meta-analyses of observational studies demonstrated that preoperative BNP elevation is associated with postoperative major adverse cardiovascular events (cardiac death, nonfatal myocardial infarction and arrhythmias with hemodynamic compromise).1),2) Current practice guidelines from the European Society of Cardiology recommend the preoperative BNP measurement for prognostication in high-risk patients (class of recommendation IIa, level of evidence B).3) In this issue, Kim and Park et al.4) present their study about the utility of BNP to predict short-term postoperative cardiovascular events in patients without history of cardiovascular disease undergoing major non-cardiac surgery. According to their definition of cardiovascular events, eight (4.5%, no death occurred) of 163 patients experienced cardiovascular events in the perioperative period. Cardiovascular events were defined at low threshold, possibly because their study population had relatively low risk profiles. The preoperative BNP levels were significantly higher in patients who underwent cardiovascular events compared with those who did not (p=0.009). With the cut-off value of >64.5 pg/mL, preoperative BNP predicted the perioperative cardiovascular events with an area under the receiver operator characteristic curve of 0.76 (95% confidence interval 0.63-0.89, p=0.014). As BNP is a continuous variable and changes quantitatively in a wide range of diseases, the higher level implies greater disease burden. From a clinical point of view, BNP could be used for additional prognostic information in patients with intermediate risk such as advanced age, anticipating major surgery or chronic illness. It is not clear which ranges of preoperative BNP levels are selected for special attention to intensify cardiac tests and perioperative management. The effect of BNP-guided intervention before surgery also remains to be elucidated. In conclusion, the work by Kim et al.4) reminds us that even in a low-risk population, higher BNP levels are associated with more postoperative cardiovascular events. Further research is needed to unite BNP into a comprehensive preoperative risk model which is applicable in various clinical situations.