Increased perioperative b-type natriuretic peptide associates with heart failure hospitalization or heart failure death after coronary artery bypass graft surgery

The Role of Natriuretic Peptides in Predicting Adverse Outcomes After Cardiac Surgery: An Updated Systematic Review

The increasing global burden of cardiovascular disease, particularly, in the aging population, has led to an increase in high-risk cardiac surgical procedures. The current preoperative risk stratification scores, such as the European System for Cardiac Operative Risk Evaluation and the Society for Thoracic Surgeons score, have limitations in their predictive accuracy and tend to underestimate the mortality risk in higher-risk populations. This systematic review aimed to evaluate the utility of natriuretic peptides, brain natriuretic peptide (BNP) and its precursor prohormone (N-terminal prohormone BNP), as predictive biomarkers for adverse outcomes after cardiac surgery. A comprehensive search strategy was performed, and 63 studies involving 40,667 patients who underwent major cardiac operations were included for data extraction. Preoperative levels of BNP and N-terminal prohormone BNP seemed to be associated with an increased risk of short- and long-term mortality, postoperative heart failure, kidney injury, and length of intensive care unit stay. However, their predictive value for postoperative arrhythmias and myocardial infarction was less established. Our findings suggest that natriuretic peptides may play an important role in risk prediction in patients who underwent cardiac surgery. The addition of these biomarkers to the existing clinical risk stratification strategies may enhance their predictive accuracy. However, this needs to be endorsed by data derived from wide-scale clinical trials.

Use of Preoperative Natriuretic Peptide in Predicting Mortality After Coronary Artery Bypass Grafting: A Systematic Review and Meta-analysis

The objective of this systematic review was to evaluate the current evidence on the utility of preoperative B-type natriuretic peptide (BNP) and N-terminal-pro B-type natriuretic peptide (NT-proBNP) in predicting short-term and long-term mortality after coronary artery bypass grafting (CABG). OVID MEDLINE, EMBASE, SCOPUS, and PUBMED were searched from 1946 to August 2022 using the following terms: "coronary artery bypass grafting" and "BNP" and "outcomes." Eligible studies included observational studies reporting the association between preoperative BNP and NT-proBNP levels and short- and long-term mortality after CABG. Articles were selected systematically, assessed for bias, and, when possible, meta-analyzed using a random effect model. After retrieving 53 articles, 11 were included for qualitative synthesis and 4 for quantitative meta-analysis. Studies included in this review showed that elevated preoperative natriuretic peptide levels, despite variable cut-offs, have been consistently shown to be associated with short- and long-term mortality after CABG. The median BNP cut-off value was 145.5 pg/mL (25th-75th percentile 95-324.25 pg/mL), and the mean NT-proBNP value was 765 ± 372 pg/mL. Compared to patients with normal natriuretic peptide levels, patients with elevated BNP and NT-proBNP presented higher mortality rates after CABG (odds ratio 3.96, 95% confidence interval 2.41-6.52; p < 0.00001). Preoperative BNP level is a powerful predictor of mortality in patients undergoing CABG. The measurement of BNP can add significant value to these patients' risk stratification and therapeutic decision-making.

Association of N-terminal pro-B-type natriuretic peptide with mortality in elderly (≥80 years) patients undergoing percutaneous coronary intervention

OBJECTIVES

The aim of this study was to determine the role of N-terminal pro-B-type natriuretic peptide (NT-proBNP) in the prognostication of patients ≥80 years of age undergoing percutaneous coronary intervention (PCI).

BACKGROUND

Elderly patients with coronary artery disease in need of PCI represent a growing patient population. Advanced risk prediction in this frail and comorbid patient population is important.

METHODS

A total of 460 consecutive patients ≥80 years of age undergoing PCI for acute (ACS) or chronic coronary syndromes (CCS) at the University Hospital Zurich, Switzerland, between January 2016 and December 2018 and with available baseline NT-proBNP levels were included in the analysis. Patients were stratified according to baseline NT-proBNP levels. The primary endpoint was all-cause mortality at a median follow-up of 33 (interquartile range: 3-392) days.

RESULTS

Median baseline NT-proBNP levels were 1411 (457-3984) ng/L. All-cause mortality was 7.8% in the lowest and 27.8% in the highest NT-proBNP quartile group (p < 0.001). In patients with ACS, all-cause mortality was 4.8% and 30.4% in the lowest and the highest NT-proBNP quartile (p < 0.001), and corresponding rates in patients with CCS were 11.1% and 22.2% (p = 0.38). In multivariable Cox regression analysis, baseline NT-proBNP levels were independently associated with an increased risk of all-cause mortality (adjusted hazard ratio: 1.00, 95% confidence interval: 1.00-1.00, p = 0.04).

CONCLUSIONS

Baseline NT-proBNP levels were identified as independent predictor of mortality in elderly (≥80 years) patients undergoing PCI. Hence, baseline NT-proBNP allows for the identification of a high-risk elderly patient subset.

Outcome of Organ Dysfunction in the Perioperative Period

While intraoperative mortality has diminished greatly over the last several decades, the risk of death within 30 days of surgery remains stubbornly high and is ultimately related to perioperative organ failure. Perioperative strokes, while rare (<2% in noncardiac surgery), are associated with a more than 10-fold increase in mortality. Rapid identification and treatment are key to maximizing long-term outcomes. Postoperative delirium (POD) and postoperative cognitive dysfunction (POCD) are separate but related perioperative neurological disorders, both of which are associated with poor long-term outcomes. To date, there are few known interventions that can ameliorate the risk of perioperative central nervous system dysfunction. Major adverse cardiac events (MACE) are a major contributor to adverse clinical outcomes following surgical procedures. Recently, advances in diagnostic strategies (eg, high-sensitivity cardiac troponin [hs-cTn] assays) have improved our understanding of MACE. Recently, the dabigatran in patients with myocardial injury after noncardiac surgery (MINS; Management of myocardial injury After NoncArdiac surGEry) trial demonstrated that a direct thrombin inhibitor could improve outcomes following MINS. While the risk of acute respiratory distress syndrome (ARDS) after surgery is approximately 0.2%, other less severe complications (eg, pneumonia, reintubation) are closer to 2%. While intensive care unit (ICU) concepts related to ARDS have migrated into the operating room, whether or not adverse pulmonary outcomes impact long-term outcomes in surgical patients remains a matter of debate. The standardization of acute kidney injury (AKI) definition has improved the ability of clinicians to measure and study the incidence of this important source of perioperative morbidity. AKI is associated with increased mortality as well as nonrenal morbidity (eg, myocardial infarction) after major surgery. Gastrointestinal complications after surgery range from ileus (common in abdominal procedures and associated with an increased length of stay) to less common complications such as mesenteric ischemia and gastrointestinal bleeding, both of which are associated with very high mortality. Outside of cardiothoracic surgery, the incidence of perioperative hepatic injury is not well described but, in this population, is associated with worsened long-term outcomes. Hyperglycemia is a common perioperative complication and occurs in patients undergoing both cardiac and noncardiac surgery. Both hyper- and hypoglycemia are associated with worsened long-term outcomes in cardiac and noncardiac surgery. Better diagnosis and increased understanding of perioperative organ injury has led to an increased appreciation for the specific role that particular organ systems play in poor long-term outcomes and has set the stage for targeted therapeutic interventions.

B-type natriuretic peptide as a surrogate marker for survival in patients undergoing cardiac surgery

Background

B-type natriuretic peptide (BNP) is a biomarker predicting morbidity and mortality in patients with congestive heart failure. However, the usefulness of pre- or postoperative BNP levels in patients undergoing cardiac surgery remains uncertain. We sought to determine the association of pre- or postoperative BNP levels on mortality in patients undergoing cardiac surgery under cardiopulmonary bypass (CPB).

Methods

This study retrospectively evaluated 1,642 patients undergoing cardiac surgery under CPB over 2 years. The primary outcomes were 30-day and overall mortality after cardiac surgery.

Results

The 30-day mortality rate was 3.0% (n=49), and the overall mortality occurred in 118 patients during the mean follow-up period of 24.9±8.9 months. In multivariable analyses, preoperative BNP level was not significantly associated with 30-day [odds ratio (OR), 1.03; 95% confidence interval (CI), 0.99–1.06; P=0.06] or overall [hazard ratio (HR), 1.01; 95% CI, 0.98–1.03; P=0.50] mortalities. However, the postoperative BNP level was significantly associated with 30-day (OR, 1.05; 95% CI, 1.02–1.09; P=0.001) and overall (HR, 1.03; 95% CI, 1.01–1.04; P=0.01) mortalities. As a sensitivity analysis, postoperative BNP levels were divided into quartiles. The top quartile (≥484 pg/mL) was identified as a strong predictor of overall mortality (HR, 2.18; 95% CI, 1.14–4.19; P=0.02).

Conclusions

Preoperative BNP level was not associated with mortality after cardiac surgery. However, postoperative BNP level was associated with mortality after cardiac surgery, especially in patients with high levels (≥484 pg/mL). Further studies in larger cohorts are necessary to validate these results.

Six-month prognostic impact of hemodynamic profiling by short minimally invasive monitoring after cardiac surgery

Introduction: Studies have shown that a hemodynamic-guided therapy improves the post operative outcomes of high-risk patients.This study, evaluated if a short period through minimally invasive hemodynamic monitoring, pressure recording analytical method (PRAM), on admission to a post-cardiac surgery step-down unit (SDU), may identify patients at higher risk of 6-month adverse events after cardiac surgery. Methods: From December 2016-May 2017,173 patients were admitted in SDU within 24-48 hours of major cardiac surgery procedure, and submitted to clinical, laboratoristic and echocardiographic evaluation and a 1-hour PRAM recording to obtain a "biohumoral snapshot" of individual patient's.156 173 patients (17 patients were lost at follow-up) were phone interviewed six months after surgery,to evaluate, as a composite end-point, the adverse events during follow-up. A multivariable logistic regression analysis was used to identify a model clinical-biohumoral (CBM) and clinical-biohumoral hemodynamics (CBHM). Results: No data from past clinical history and no conventional risk score (EuroScore II, STS score)independently predicted the risk of 6-month major events in our study. The risk of adverse events at six-month follow-up was directly related, in the CBM, to sustained post-operative cardiac arrhythmias, higher values of NT-proBNP and of arterial pH; inversely related to values of hs-C-reactive protein (hs-CRP) and, in the CBHM, to low values of cardiac cycle efficiency (CCE) and dP/dt_max. Conclusion: Our study although limited by its observational nature and by the limited number of patients enrolled, showed that a short period of minimally invasive hemodynamic monitoring increased the accuracy to identify patients at major risk of mid-term events after cardiac surgery.

Low and elevated B-type natriuretic peptide levels are associated with increased mortality in patients with preserved ejection fraction undergoing transcatheter aortic valve replacement: an analysis of the PARTNER II trial and registry

Aims

B-type natriuretic peptide (BNP) is a cardiac neurohormone that is secreted in response to ventricular volume expansion and pressure overload. There are conflicting data regarding the association between BNP levels and outcomes after transcatheter aortic valve replacement (TAVR). We therefore sought to assess the association between baseline BNP and adverse outcomes in patients with symptomatic, severe aortic stenosis (AS), and left ventricular ejection fraction (LVEF) ≥50%, undergoing TAVR in the PARTNER 2 Trial and Registry.

Methods and results

A total of 1782 patients were included in the analysis, and BNP was evaluated both as a continuous log-transformed value and by a priori categories: low (&lt;50 pg/mL), normal (≥50 and &lt;100 pg/mL), moderately elevated (≥100 and &lt;400 pg/mL), or markedly elevated (≥400 pg/mL). Clinical outcomes from discharge to 2 years were compared between patients according to their baseline BNP level, using Kaplan–Meier event rates and multivariable Cox proportional hazards regression models. After adjustment, spline curves revealed a non-linear association between log-transformed BNP and all-cause and cardiovascular mortality in which both the lowest and highest values were associated with increased mortality. Two-year all-cause mortality rates for those with low (n = 86), normal (n = 202), moderately elevated (n = 885), and markedly elevated (n = 609) baseline BNP were 20.0%, 9.8%, 17.7%, and 26.1%, respectively. In adjusted models, compared to a normal baseline BNP, low [adjusted hazard ratio (HR) 2.6, 95% confidence interval (CI) 1.3–5.0, P-value 0.005], moderately elevated (adjusted HR 1.6, 95% CI 1.0–2.6, P-value 0.06), and markedly elevated (adjusted HR 2.1, 95% CI 1.3–3.5, P-value 0.003) BNP were associated with increased all-cause mortality, driven by cardiovascular mortality.

Conclusions

In a large cohort of patients with severe symptomatic AS and preserved LVEF undergoing TAVR, all-cause and cardiovascular mortality rates at 2 years were higher in patients with low and markedly elevated BNP levels.

Clinical Trial Registration

https://clinicaltrials.gov/ unique identifier #NCT01314313, #NCT02184442, #NCT03222128, and #NCT03222141.

Perioperative Biomarkers Predicting Postoperative Atrial Fibrillation Risk After Coronary Artery Bypass Grafting: A Narrative Review

Postoperative atrial fibrillation (POAF) after cardiac surgery remains a highly prevalent and costly condition that negatively impacts patient quality of life and survival. Numerous retrospective studies, meta-analysis, and review papers have been reported identifying POAF risk based on patients' risk factors and clinical biomarkers. In this narrative review, the authors report significant variations among selected pre- and perioperative biomarkers used to predict POAF incidence in patients without a history of atrial fibrillation (AF). POAF prediction based on B-type natriuretic peptide, N-terminal pro B-type natriuretic peptide, C-reactive protein, interleukin-6, creatinine, and plasminogen activator inhibitor-1 differs significantly among different studies, thereby limiting their clinical utility to predict POAF risk with high accuracy. Conversely, soluble vascular endothelial cells adhesion molecule-1, soluble CD40 ligand, Galectin-3, and aldosterone show promise for better POAF prediction. However, the current datasets for these selected biomarkers are not of sufficient size to validate the broad clinical application specifically for patients with no prior history of AF.

Natriuretic Peptides in Cardiac Anesthesia and Intensive Care

Natriuretic peptides, predominantly B-type, are widely used in cardiology as prognostic and diagnostic biomarkers or, much less often, as a substantive treatment tool. They are hormones that are produced mainly in the myocardium in response to overload and ischemia, and their level quite accurately reflects the degree of myocardial dysfunction. Although their use in cardiac anesthesia and intensive care setting seems to be very beneficial for assessing the risk of acute disturbance of myocardial function or its laboratory monitoring, the actual significance of natriuretic peptides in this area is not yet recognized. This is due to the lack of clear diagnostic and prognostic values for these biomarkers supported by high-quality researches. On the basis of the available data, main advantages, existing difficulties, and most effective ways of using natriuretic peptides for determining the risk of heart surgery and assessing the severity of sepsis, pneumonia, and other critical conditions have been discussed in this review. In addition, the expediency of using natriuretic peptides as target parameters for goal-oriented therapy and as a substantive tool for treatment is considered.

B-Type Natriuretic Peptide Assessment in Patients Undergoing Revascularization for Left Main Coronary Artery Disease

Background:

Elevated B-type natriuretic peptide (BNP) is reflective of impaired cardiac function and is associated with worse prognosis among patients with coronary artery disease (CAD). We sought to assess the association between baseline BNP, adverse outcomes, and the relative efficacy of percutaneous coronary intervention (PCI) versus coronary artery bypass grafting (CABG) in patients with left main CAD.

Methods:

The EXCEL trial (Evaluation of XIENCE Versus Coronary Artery Bypass Surgery for Effectiveness of Left Main Revascularization) randomized patients with left main CAD and low or intermediate SYNTAX scores (Synergy Between PCI With TAXUS and Cardiac Surgery) to PCI with everolimus-eluting stents versus CABG. The primary end point was the composite of all-cause death, myocardial infarction, or stroke. We used multivariable Cox proportional hazards regression to assess the associations between normal versus elevated BNP (≥100 pg/mL), randomized treatment, and the 3-year risk of adverse events.

Results:

BNP at baseline was elevated in 410 of 1037 (39.5%) patients enrolled in EXCEL. Patients with elevated BNP levels were older and more frequently had additional cardiovascular risk factors and lower left ventricular ejection fraction than those with normal BNP, but had similar SYNTAX scores. Patients with elevated BNP had significantly higher 3-year rates of the primary end point (18.6% versus 11.7%; adjusted hazard ratio [HR], 1.62; 95% confidence interval [CI], 1.16–2.28; P =0.005) and higher mortality (11.5% versus 3.9%; adjusted HR, 2.49; 95% CI, 1.48–4.19; P =0.0006), both from cardiovascular and noncardiovascular causes. In contrast, there were no significant differences in the risks of myocardial infarction, stroke, ischemia-driven revascularization, stent thrombosis, graft occlusion, or major bleeding. A significant interaction ( P interaction =0.03) was present between elevated versus normal BNP and treatment with PCI versus CABG for the adjusted risk of the primary composite end point at 3 years among patients with elevated BNP (adjusted HR for PCI versus CABG, 1.54; 95% CI, 0.96–2.47) versus normal BNP (adjusted HR, 0.74; 95% CI, 0.46–1.20). This interaction was stronger when log(BNP) was modeled as a continuous variable ( P interaction =0.002).

Conclusions:

In the EXCEL trial, elevated baseline BNP levels in patients with left main CAD undergoing revascularization were independently associated with long-term mortality but not nonfatal adverse ischemic or bleeding events. The relative long-term outcomes after PCI versus CABG for revascularization of left main CAD may be conditioned by the baseline BNP level.

Clinical Trial Registration:

URL: https://www.clinicaltrials.gov . Unique identifier: NCT01205776.

The Association Between Novel Biomarkers and 1-Year Readmission or Mortality After Cardiac Surgery

BACKGROUND

Novel cardiac biomarkers including soluble suppression of tumorigenicity 2, galectin-3, and the N-terminal prohormone of brain natriuretic peptide may be associated with long-term adverse outcomes after cardiac surgery. We sought to measure the association between cardiac biomarker levels and 1-year hospital readmission or mortality.

METHODS

Plasma biomarkers from 1,047 patients discharged alive after isolated coronary artery bypass graft surgery from 8 medical centers were measured in a cohort from the Northern New England Cardiovascular Disease Study Group between 2004 and 2007. We evaluated the association between preoperative and postoperative biomarkers and 1-year readmission or mortality using Kaplan-Meier estimates and Cox proportional hazards modeling, adjusting for covariates used in The Society of Thoracic Surgeons 30-day readmission model.

RESULTS

The median follow-up time was 365 days. After adjustment for established risk factors, above-median levels of postoperative galectin-3 (median 10.35 ng/mL; hazard ratio, 1.40; 95% confidence interval, 1.08 to 1.80; p = 0.010) and N-terminal prohormone of brain natriuretic peptide (median = 15.21 ng/mL, hazard ratio, 1.42; 95% confidence interval, 1.07 to 1.87; p = 0.014) were each significantly associated with 1-year readmission or mortality.

CONCLUSIONS

In patients undergoing cardiac surgery, novel cardiac biomarkers were associated with readmission or mortality independent of established risk factors. Measurement of these biomarkers may improve our ability to identify patients at highest risk for readmission or mortality before discharge. This will also allow resource allocation accordingly, while implementing strategies for personalized medicine based on the biomarker profile of the patient.

Pharmacogenomics of the Natriuretic Peptide System in Heart Failure

PURPOSE OF REVIEW

Heart failure (HF) continues to be a public health burden despite advances in therapy, and the natriuretic peptide (NP) system is clearly of critical importance in this setting, spawning valuable diagnostic and prognostic testing, such as B-type natriuretic peptide (BNP) and N-terminal pro-BNP (NT-proBNP), as well as current and future therapeutics, including recombinant natriuretic peptides (e.g., carperitide, nesiritide) and recently sacubitril, which inhibits the key clearance mechanism for NPs. This article intends to summarize the existing evidence for the role of NP system genetic variation on cardiovascular phenotypes relevant to HF with particular focus on the potential impact on pharmacologic therapies.

RECENT FINDINGS

Several genes in NP system have been interrogated, in many cases genetic variation impacting protein quantity and function or related disease states. Recent data supports genetic variants potentially impacting pharmacokinetics or dynamics of medications targeting the pathway. Growing evidence indicates the importance of genetic variation to the functioning of the NP system and its pharmacologic manipulation.

Absolute Postoperative B-Type Natriuretic Peptide Concentrations, but Not Their General Trend, Are Associated With 12-Month, All-Cause Mortality After On-Pump Cardiac Surgery

BACKGROUND

B-type natriuretic peptide (BNP) is a predictor of mortality after on-pump cardiac surgery. However, previous limited and heterogeneous studies have focused on peak concentrations at 3 to 5 days after surgery and may not offer clinicians much help in early decision-making. After confirming the predictive value of first-postoperative-day BNP in a preliminary analysis, we explored the association between isolated second-postoperative-day BNP concentrations, second-day BNP concentrations in conjunction with first-day BNP concentrations, and the change in BNP (ie, ΔBNP) from the first to the second postoperative day and 12-month, all-cause mortality.

METHODS

We included consecutive patients undergoing on-pump cardiac surgery in this observational, secondary analysis of prospectively collected data. We analyzed biomarkers on the first and second postoperative day. ΔBNP was defined as BNP on the second postoperative day minus BNP on the first postoperative day. The primary end point was 12-month, all-cause mortality. The secondary end point was a composite of major adverse cardiac events (MACEs) at 12 months and/or all-cause mortality at 12 months. MACE was defined as nonfatal cardiac arrest, myocardial infarction, and congestive heart failure. The association between BNP and outcomes was examined by receiver operating characteristic curves, as well as univariate and multivariable logistic regression, adjusting for the EuroSCORE II, cross-clamp time, and first-postoperative-day troponin T.

RESULTS

We included 1199 patients in the preliminary analysis focused on BNP on postoperative day 1. In the analyses examining BNP variables requiring second-postoperative-day BNP measurement (n = 708), we observed 66 (9.3%) deaths, 48 (6.8%) MACE, and 104 (14.7%) deaths and/or MACE. Both first- and second-postoperative-day BNP were significant independent predictors of all-cause, 12-month mortality per 100 ng/L increase (adjusted odds ratio [aOR], 1.040 [95% confidence interval (CI), 1.019-1.065] and 1.064 [95% CI, 1.031-1.105], respectively). When used in conjunction with one another, first-day BNP was not significant (aOR, 1.021 [95% CI, 0.995-1.048]), while second-day BNP remained significant (aOR, 1.046 [95% CI, 1.008-1.091]). The ΔBNP per 100 ng/L increase was not associated with 12-month, all-cause mortality in the univariable (OR, 0.977 [95% CI, 0.951-1.007]) or multivariable analysis (aOR, 0.989 [95% CI, 0.962-1.021]).

CONCLUSIONS

Both absolute concentrations of first- and second-postoperative-day BNP are independent predictors of 12-month, all-cause mortality. When modeled together, second-postoperative-day BNP is more predictive of 12-month, all-cause mortality. Although intuitively appealing, the change in BNP from the first to the second postoperative day is a complex variable and should not routinely be used for prognostication.

B-type Natriuretic Peptide Predicts Morbidity and Long-Term Mortality in Coronary Artery Bypass Grafting and Valve Surgery

OBJECTIVE

To assess whether B-type natriuretic peptide (BNP) levels are a useful predictor of morbidity and mortality as well as long-term survival in patients after coronary artery bypass grafting (CABG) and valve surgery.

METHODS

A retrospective review of CABG and/or valve surgery patients from 2012 to 2015 at a single center was conducted. A total of 432 patients were identified (CABG, 295 patients; valve, 82 patients; and CABG + valve, 55 patients). B-type natriuretic peptide levels were divided into quartiles (Q1-Q4). Mortality data were available for up to 3.4 years after surgery.

RESULTS

B-type natriuretic peptide quartile was independently associated with any complication on multivariate analysis. Patients in Q4 were at highest risk (adjusted odds ratio, 3.81; P = 0.047 vs Q1). There was a significant association between BNP quartile and time to death (log-rank χ, 8.30; P = 0.04) with greatest association 9 months postoperatively. B-type natriuretic peptide quartile was significantly associated with time to death in Cox regression in Q2 (hazard ratio [HR], 3.73 (1.04-13.44); P = 0.044) and Q4 (HR, 4.33 (1.14-16.44); P = 0.031). Q3 also had a higher risk of death (HR, 3.5 vs Q1); however, this was only significant at a trend level (P = 0.06). Using a risk model generated from logistic regression, we determined that the highest risk group had relative risk of complications 30 times higher than the lowest risk group.

CONCLUSIONS

B-type natriuretic peptide levels are an independent predictor of morbidity after CABG and/or valve surgery regardless of type of procedure or on/off bypass usage. B-type natriuretic peptide levels also correlate with time to death, highlighting the need for sustained follow-up and heart failure management to improve survival in patients with elevated BNP levels presenting for all cardiac surgery.

Minor Postoperative Increases of Creatinine Are Associated with Higher Mortality and Longer Hospital Length of Stay in Surgical Patients

BACKGROUND

Surgical patients frequently experience postoperative increases in creatinine levels. The authors hypothesized that even small increases in postoperative creatinine levels are associated with adverse outcomes.

METHODS

The authors examined the association of postoperative changes from preoperative baseline creatinine with all-cause in-hospital mortality and hospital length of stay (HLOS) in a retrospective analysis of surgical patients at a single tertiary care center between January 2006 and June 2012.

RESULTS

The data of 39,369 surgical patients (noncardiac surgery n = 37,345; cardiac surgery n = 2,024) were analyzed. Acute kidney injury (AKI)-by definition of the Kidney Disease: Improving Global Outcome group-was associated with a five-fold higher mortality (odds ratio [OR], 4.8; 95% CI, 4.1 to 5.7; P < 0.001) and a longer HLOS of 5 days (P < 0.001) after adjusting for age, sex, comorbidities, congestive heart failure, preoperative hemoglobin, preoperative creatinine, exposure to radiocontrast agent, type of surgery, and surgical AKI risk factors. Importantly, even minor creatinine increases (Δcreatinine 25 to 49% above baseline but < 0.3 mg/dl) not meeting AKI criteria were associated with a two-fold increased risk of death (OR, 1.7; 95% CI, 1.3 to 2.4; P < 0.001) and 2 days longer HLOS (P < 0.001). This was more pronounced in noncardiac surgery patients. Patients with minor creatinine increases had a five-fold risk of death (OR, 5.4; 95% CI, 1.5 to 20.3; P < 0.05) and a 3-day longer HLOS (P < 0.01) when undergoing noncardiac surgery.

CONCLUSIONS

Even minor postoperative increases in creatinine levels are associated with adverse outcomes. These results emphasize the importance to find effective therapeutic approaches to prevent or treat even mild forms of postoperative kidney dysfunction to improve surgical outcomes.

Plasma corin decreases after coronary artery bypass graft surgery and is associated with postoperative heart failure: a pilot study

OBJECTIVE

Corin is a natriuretic peptide-converting enzyme that cleaves precursor pro-B-type natriuretic peptide to active B-type natriuretic peptide (BNP) (diuretic, natriuretic, and vasodilatory properties). Increased plasma BNP is a known diagnostic and prognostic heart failure (HF) biomarker in ambulatory and surgical patients. Recent studies indicate that plasma corin is decreased significantly in chronic HF patients, yet perioperative plasma corin concentrations have not been assessed in cardiac surgical patients. The objectives of this study were to determine the effect of coronary artery bypass graft (CABG) surgery with cardiopulmonary bypass (CPB) on plasma corin concentrations and to assess the association between change in perioperative plasma corin concentration and long-term postoperative HF hospitalization or death. It was hypothesized that plasma corin concentrations decrease significantly from preoperative baseline during postoperative days 1 to 4 and that hospitalization or death from HF during the 5 years after surgery is associated with higher relative difference (preoperative baseline to postoperative nadir) in plasma corin concentrations.

DESIGN

Prospective observational pilot study.

SETTING

Two institutions: Brigham and Women's Hospital, Boston, Massachusetts and the Texas Heart Institute, St. Luke's Hospital, Houston, Texas.

PARTICIPANTS

99 patients of European ancestry who underwent isolated primary CABG surgery with CPB.

INTERVENTIONS

Nonemergency isolated primary CABG surgery with CPB.

MEASUREMENTS AND MAIN RESULTS

Plasma corin concentration was assessed preoperatively and at 4 postoperative time points (postoperative days 1-4). HF hospitalization or HF death events during the 5 years after surgery were identified by review of hospital and death records. Postoperative plasma corin concentrations were significantly lower than preoperative baseline concentrations (p<0.0001). Perioperative corin concentrations were significantly higher in males than in females (p<0.0001). Fifteen patients experienced long-term postoperative HF events. Patients who experienced HF hospitalization or HF death during study follow-up had significantly higher relative difference in plasma corin concentration (preoperative baseline to postoperative nadir) than patients who did not experience HF events during study follow-up (p=0.03).

CONCLUSIONS

Plasma corin concentrations decrease significantly from preoperative concentrations after CABG surgery. HF hospitalization or HF death during the 5 years after CABG surgery with CPB is associated with larger relative decrease in plasma corin concentration from preoperative baseline. Further investigation is warranted to determine the role of corin in postoperative HF biology.

Noteworthy articles in 2013 for cardiothoracic anesthesiologists

In 2013, the field of cardiothoracic anesthesiology has continued to grow at the same astounding rate as in previous years. It has become increasingly difficult for practicing anesthesiologists to stay current on impactful publications related to our exciting subspecialty. The scientific output has expanded to such a great extent that following the literature in specialty journals barely scrapes the surface of available knowledge. With the recent emphasis on teamwork spanning multiple medical specialties in the care for complex patients, the door has opened for our research to be presented in nontraditional, nonanesthesiology venues. In this review, we have selected a small sample of noteworthy contributions to the field of cardiothoracic and vascular anesthesiology published in 2013 with potential impact on our clinical practice.