Red cell distribution width predicts new-onset atrial fibrillation after coronary artery bypass grafting

Clinical practices for defining, detecting, and diagnosing postoperative atrial fibrillation after coronary revascularization surgery - A scoping review

OBJECTIVES

This scoping review was undertaken to understand the degree of variation in clinical practices associated with postoperative atrial fibrillation (POAF), following coronary revascularization surgery by collating and synthesising key concepts from current published literature.

REVIEW METHODS AND DATA SOURCES

This scoping review was conducted following the framework outlined by Askey and O'Malley. Reporting of this scoping review follows the Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for Scoping Reviews checklist. Initial searches were completed in September 2020 and updated in January 2023. Comprehensive searches to identify relevant published literature were carried out within CINAHL, MEDLINE, and ProQuest databases. All searches were limited to full-text papers published in English with human adult participants. Deductive content analysis using NVivo software was performed to synthesise the data.

RESULTS

A total of 692 studies were identified during the database searches. After the deletion of duplicates and the application of the inclusion and exclusion criteria, 73 studies were included in the scoping review. The included studies were published between 2001 and 2022 and included a total of 24,833 participants. Forty-six studies included a definition of POAF, with four of these citing a peak-body definition. A total of 24 included studies reported on electrocardiogram diagnostic criteria for POAF, with 13/24 [54%] describing these characteristics within their definition. The time-based diagnostic criteria ranged from a minimum duration of greater than 30 seconds to greater than 1 hour. The most frequently reported minimum-time thresholds were ≥30 seconds, reported in 12 of 51 (24%) studies and ≥5 min, reported in 13 of 51 (25%) studies.

CONCLUSIONS

There is a lack of consistency in clinical practice for defining, detecting, and diagnosing POAF, following coronary revascularization surgery. Consensus and standardisation of clinical practices are urgently needed.

Is Red Cell Distribution Width a Reliable Marker for Cardiovascular Diseases? A Narrative Review

Red cell distribution width (RDW) is an easy-to-access marker which is routinely measured in complete blood count (CBC) test. Besides the classic use of RDW as a marker for discriminating different types of anemia, recent studies had indicated the relationship between high RDW and cardiovascular diseases. High RDW is not only useful in the diagnosis and prognostication of various cardiovascular conditions but also could be used as a valuable tool for predicting the incidence of cardiovascular diseases. population-based studies have indicated that higher RDW could effectively predict the incidence of heart failure (HF), atherosclerotic diseases, and atrial fibrillation (AF). It has been also demonstrated that higher RDW is associated with worse outcomes in these diseases. Recent studies have shown that high RDW is also associated with other cardiovascular conditions including cardiomyopathies, and pulmonary hypertension. The predictive role of RDW in endovascular interventions has also been demonstrated by many recent studies. Here in this review, we attempt to compile the most recent findings with older reports regarding the relation between high RDW and HF, cardiomyopathies, pulmonary hypertension, AF, atherosclerotic disorders, primary hypertension, and the outcomes of endovascular interventions. we also discussed the role of RDW in the prognostication of different cardiovascular conditions when combined with classic classification criteria.

Predictive Value of the Hb/RDW Ratio for the Risk of All-Cause Death in Patients with Heart Failure with Different Ejection Fractions

INTRODUCTION

The prognostic value of the ratio of haemoglobin to red cell distribution width (HRR) in different types of heart failure (HF) is not well known.

METHOD AND RESULTS

We analysed the long-term prognostic value of HRR in patients with HF using the Cox proportional risk model and Kaplan-Meier method. We reviewed consecutive 972 HF patients. The overall mortality rate was 45.68%. Mortality was 52.22% in the HFrEF group and 40.99% in the HFpEF + HFmrEF group. Cox regression showed that when HRR increased by 1 unit, the risk of all-cause death in all HF patients decreased by 22.8% (HR: 0.772, 95% CI: 0.724, 0.823, p < 0.001), in the HFpEF + HFmrEF group it decreased by 15.5% (HR: 0.845, 95% CI: 0.774, 0.923, p < 0.001), and in the HFrEF group it decreased by 36.1% (HR: 0.639, 95% CI: 0.576, 0.709, p < 0.0001). Subgroup analysis showed that there were interactions between the EF and HRR groups. The group in which HRR best predicted all-cause death from HF was group 1 (EF <40%, HRR <9.45), followed by group 2 (EF <40%, HRR ≥9.45), and group 3 (EF ≥40%, HRR <9.45). HRR had no predictive value in group 4 (EF ≥40%, HRR ≥9.45).

CONCLUSION

HRR is an important predictor of all-cause mortality in patients with HF, especially HFrEF. There is an interaction between HRR group and LVEF group.

The Prognostic Significance of Red Cell Distribution Width in Cardiac Surgery: A Systematic Review and Meta-Analysis

RED CELL DISTRIBUTION WIDTH (RDW) is a routinely available biomarker of likely erythropoietic dysfunction, which may be associated with adverse outcomes after cardiac surgery. This systematic review and meta-analysis aimed to clarify the prognostic value of RDW in patients undergoing cardiac surgery. The authors searched MEDLINE, Embase, and the Cochrane Library from inception to May 10, 2022 for studies investigating the association between elevated RDW (as defined by the authors of included studies) and adverse outcomes after cardiac surgery. Herein, the authors extracted maximally adjusted hazard ratios (HRs) and odds ratios (ORs) with associated CIs, and pooled them using random-effects inverse- variance modeling. The authors explored interstudy heterogeneity using metaregression. The authors included 26 studies involving 48,092 patients who had undergone cardiac surgery. Elevated preoperative RDW was associated with long-term mortality (pooled HR 1.63, 95% CI 1.05-2.52), short-term mortality (pooled OR 2.16, 95% CI 1.21-3.87), acute kidney injury (AKI; pooled OR 1.30, 95% CI 1.19-1.41) and postoperative atrial fibrillation (POAF; pooled OR 1.44, 95% CI 1.05-1.96). Some studies suggested a significant association between preoperative RDW elevation and neurologic complications; however, their number was insufficient for meta-analysis. The postoperative RDW levels were less consistently reported and could not be meta-analyzed. In conclusion, the authors found that elevated preoperative RDW was associated with increased short- and long-term mortality, POAF, and AKI after cardiac surgery. Further research is needed to investigate its role in the risk stratification of patients undergoing cardiac surgery.

Predicting atrial fibrillation after cardiac surgery: a scoping review of associated factors and systematic review of existing prediction models

INTRODUCTION

Postoperative atrial fibrillation (POAF) is common after cardiac surgery and associated with increased hospital length of stay, patient morbidity and mortality. We aimed to identify factors associated with POAF and evaluate the accuracy of available POAF prediction models.

METHODS

We screened articles from Ovid MEDLINE® and PubMed Central® (PMC) and included studies that evaluated risk factors associated with POAF or studies that designed or validated POAF prediction models. We only included studies in cardiac surgical patients with sample size n ⩾ 50 and a POAF outcome group ⩾20. We summarised factors that were associated with POAF and assessed prediction model performance by reviewing reported calibration and discriminative ability.

RESULTS

We reviewed 232 studies. Of these, 142 fulfilled the inclusion criteria. Age was frequently found to be associated with POAF, while most other variables showed contradictory findings, or were assessed in few studies. Overall, 15 studies specifically developed and/or validated 12 prediction models. Of these, all showed poor discrimination or absent calibration in predicting POAF in externally validated cohorts.

CONCLUSIONS

Except for age, reporting of factors associated with POAF is inconsistent and often contradictory. Prediction models have low discrimination, missing calibration statistics, are at risk of bias and show limited clinical applicability. This suggests the need for studies that prospectively collect AF relevant data in large cohorts and then proceed to validate findings in external data sets.

Can Red Blood Cell Distribution Width Predict Laryngectomy Complications or Survival Outcomes?

OBJECTIVE

Red blood cell distribution width (RDW), a reported biomarker for morbidity and mortality in chronic disease and following certain surgeries, has not been well-studied in head and neck cancer patients. The aim of the study was to examine the association of RDW with postoperative complications and survival among patients who underwent primary or salvage laryngectomy.

METHODS

We analyzed a retrospective case series study of patients diagnosed with squamous cell carcinoma of the larynx treated with total laryngectomy. Survival outcomes were examined using Kaplan-Meier analysis.

RESULTS

One hundred seventy-seven patients were included in the final analysis. The most common tumor subsite was the supraglottis (60%). On bivariate analysis, patients with RDW ≥14.5 had higher prevalence of non-surgical, systemic complications, including deep venous thrombosis, pneumonia, cardiovascular events, and difficulty weaning from mechanical ventilation. However, there was no significant difference in laryngectomy-specific post-operative complications, including pharyngocutaneous fistula, wound infection, stoma complications, and chyle leak. RDW was not found to be associated with survival outcomes following laryngectomy.

CONCLUSIONS

Among laryngectomy patients, RDW ≥14.5 is associated with higher prevalence of systemic morbidity, but not with specific local surgical complications or decreased survival.

Prognostic significance of the mean corpuscular volume (MCV) and red cell distribution width (RDW) in obstructive colorectal cancer patients with a stent inserted as a bridge to curative surgery

PURPOSE

The prognostic significance of the mean corpuscular volume (MCV) and red cell distribution width (RDW) in patients with malignancy have not been intensely investigated and are largely overlooked. We, therefore, investigated the clinical significance of MCV and RDW in non-metastatic obstructive colorectal cancer (OCRC) patients with a self-expandable metallic stent inserted as a bridge to curative surgery.

METHODS

Eighty-five pathological stage II and III OCRC patients were retrospectively evaluated. The associations of the preoperative MCV and RDW values with short- and long-term outcomes were examined.

RESULTS

There were 50 males and 35 females, and the median age was 71 years old. The median interval between stenting and surgery was 17 days, and the median postoperative hospital stay was 16 days. Fifty-six patients were in the MCV ≥ 87 group, and 47 were in the RDW ≥ 13.8 group. Multivariate analyses revealed the MCV ≥ 87 status to be independently associated with a poor relapse-free survival (hazard ratio [HR] = 4.70, 95% confidence interval [CI] 1.52-14.58, P = 0.007). The RDW ≥ 13.8% was an independent predictor of postoperative infectious complications (HR = 7.28, 95% CI 1.24-42.70, P = 0.028).

CONCLUSION

The MCV and RDW are simple but strong predictors of postoperative outcomes in OCRC patients.

Association of red blood cell distribution width with postoperative new-onset atrial fibrillation following cardiac valve replacement surgery: A retrospective study

PURPOSE

The aim of this study was to evaluate the impact of preoperative red blood cell distribution width (RDW) values on the risk of postoperative new-onset atrial fibrillation (PNAF) during hospitalization following cardiac valve replacement surgery.

MATERIALS AND METHODS

The clinical data of 148 patients with preoperative sinus rhythm who underwent cardiac valve replacement surgery at The First Affiliated Hospital of Anhui Medical University from September 2017 to June 2018 were retrospectively analyzed. Univariate and multivariate logistic regression analyses were used to determine the relationship between preoperative RDW values and the development of PNAF.

RESULTS

Forty-nine of the 148 patients (33.1%) developed PNAF. The median preoperative RDW was 13.1 (12.6-17.2), while the median RDW value was significantly higher in patients with PNAF than in those without PNAF [14.1 (13.2-15.0) vs. 12.9 (12.4-13.5), P < 0.001]. Multivariate logistic regression analysis showed that preoperative RDW values were significantly correlated with the occurrence of PNAF (odds ratio: 1.940, 95% confidence interval: 1.377 to 2.731, P < 0.001).

CONCLUSIONS

Preoperative RDW is an independent risk factor for PNAF during hospitalization following cardiac valve replacement surgery. This finding suggests that preoperative RDW measurement may be used to stratify the risk for PNAF development in patients undergoing cardiac surgery.

Role of pre-operative red cell distribution width estimation in the prediction of in-hospital mortality after off-pump coronary artery bypass grafting

Background

Red cell distribution width (RDW) level is routinely provided in a simple and inexpensive complete blood count report. However, RDW is sometimes overlooked. Recently a higher RDW level is found associated with postoperative mortality after off-pump coronary artery bypass. Many risk-prediction tools are available, like the European System for Cardiac Operative Risk Evaluation, Society of Thoracic Surgeons score, etc. but all need improvement for better prediction. So, a new risk-factor should be discovered which is simple enough for clinical use and cost-effective, and improves the risk assessment tools that help to predict and avoid preventable mortality following cardiac surgery.

Methods

The prospective study was conducted, taking a total of 150 patients of coronary artery disease who underwent elective isolated off-pump coronary artery bypass. The study population was grouped according to their preoperative RDW level as Group A (RDW ≤ 14%), Group B (RDW 14–16%), and Group C (RDW ≥ 16%). The receiver operating characteristic (ROC) curve was constructed and multivariate regression analysis was done to see the predictive value of RDW for in-hospital mortality.

Results

The mortality rate was 2.7%, N = 150. ROC curve revealed Area Under the Curve 0.841 and p = 0.020 that indicates the RDW as the reliable predictor for in-hospital mortality. Multivariate regression analysis showed the RDW to be the only variable independently predicting in-hospital mortality after off-pump coronary artery bypass among possible haematological predictors. (OR 1.838, 95% CI 1.061–3.186, p = 0.030).

Conclusion

Preoperative raised RDW level is a novel predictor of in-hospital mortality after off-pump coronary artery bypass. Further studies should be done to determine the associated mechanism.

Prognostic Value of Red Blood Cell Distribution Width in Transcatheter Aortic Valve Replacement Patients

OBJECTIVE

Elevated red blood cell distribution width (RDW) level has been shown to be associated with poor outcomes in patients with cardiovascular disease. Limited data are available regarding the prognostic value of RDW in transcatheter aortic valve replacement (TAVR) patients. Therefore, we aimed to investigate the impact of RDW variation on outcomes of TAVR patients.

METHODS

From March 20, 2012, to February 20, 2020, the pre-TAVR RDW levels of 1,163 consecutive TAVR patients were examined. Receiver operating curves were set to define the most accurate cut-point, which was subsequently validated in our validation set. Associations of RDW levels with early and long-term outcomes were investigated.

RESULTS

A total of 988 patients were eligible for the analysis. Patients with 30-day, 1-year, and 7-year mortality had significantly higher pre-TAVR RDW levels (15.8% [12.9-19.1] vs 14.7% [11.6-26.3], P = 0.01; 16% [12.3-26.3] vs 14.7% [11.6-24.3], P < 0.001; 15.6% [12.3-26.3] vs 14.6% [11.6-24.3], P < 0.001, respectively). A RDW of 14.5% was found as the most sensitive and specific cut-point for mortality at 1 and 7 years (HR = 2.6, 95% CI: 1.6-4.2, P < 0.001; HR = 1.8, 95% CI: 1.3-2.4, P < 0.001), with mortality of 22% versus 10% at 1 year (P < 0.001) and 37% versus 27% at 7 years (P < 0.001) in patients with RDW ≥14.5% versus those with RDW <14.5%.

CONCLUSIONS

RDW is an important prognostic factor in TAVR patients. A RDW level higher than 14.5% is significantly associated with post-TAVR early and late mortality. RDW levels should be incorporated into current risk assessment models as an additional variable to predict post-TAVR outcomes.

Role of pre-operative red cell distribution width estimation in the prediction of in-hospital mortality after off-pump coronary artery bypass grafting

Background

Red cell distribution width (RDW) level is routinely provided in a simple and inexpensive complete blood count report. However, RDW is sometimes overlooked. Recently a higher RDW level is found associated with postoperative mortality after off-pump coronary artery bypass. Many risk-prediction tools are available, like the European System for Cardiac Operative Risk Evaluation, Society of Thoracic Surgeons score, etc. but all need improvement for better prediction. So, a new risk-factor should be discovered which is simple enough for clinical use and cost-effective, and improves the risk assessment tools that help to predict and avoid preventable mortality following cardiac surgery.

Methods

The prospective study was conducted, taking a total of 150 patients of coronary artery disease who underwent elective isolated off-pump coronary artery bypass. The study population was grouped according to their preoperative RDW level as Group A (RDW ≤ 14%), Group B (RDW 14–16%), and Group C (RDW ≥ 16%). The receiver operating characteristic (ROC) curve was constructed and multivariate regression analysis was done to see the predictive value of RDW for in-hospital mortality.

Results

The mortality rate was 2.7%, N = 150. ROC curve revealed Area Under the Curve 0.841 and p = 0.020 that indicates the RDW as the reliable predictor for in-hospital mortality. Multivariate regression analysis showed the RDW to be the only variable independently predicting in-hospital mortality after off-pump coronary artery bypass among possible haematological predictors. (OR 1.838, 95% CI 1.061–3.186, p = 0.030).

Conclusion

Preoperative raised RDW level is a novel predictor of in-hospital mortality after off-pump coronary artery bypass. Further studies should be done to determine the associated mechanism.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13019-021-01612-w.

Incidence of Laryngotracheal Stenosis after Thermal Inhalation Airway Injury

Inhalation injury is independently associated with burn mortality, yet little information is available on the incidence, risk factors, or functional outcomes of thermal injury to the airway. In patients with thermal inhalation injury, we sought to define the incidence of laryngotracheal stenosis (LTS), delineate risk factors associated with LTS development, and assess long-term tracheostomy dependence as a proxy for laryngeal function. Retrospective cohort study of adult patients treated for thermal inhalation injury at a single institution burn critical care unit from 2012 to 2017. Eligible patients' records were assessed for LTS (laryngeal, subglottic, or tracheal stenosis). Patient characteristics, burn injury characteristics, and treatment-specific covariates were assessed. Descriptive statistics, Mann-Whitney U-tests, odds ratio, and chi-square tests compared LTS versus non-LTS groups. Of 129 patients with thermal inhalation injury during the study period, 8 (6.2%) developed LTS. When compared with the non-LTS group, patients with LTS had greater mean TBSA (mean 30.3, Interquartile Range 7-57.5 vs 10.5, Interquartile Range 0-15.12, P = .01), higher grade of inhalation injury (mean 2.63 vs 1.80, P = .05), longer duration of intubation (12.63 vs 5.44; P < .001), and greater inflammatory response (mean white blood cell count on presentation 25.8 vs 14.9, P = .02, mean hyperglycemia on presentation 176.4 vs 136.9, P = .01). LTS patients had a significantly higher rate of tracheostomy dependence at last follow-up (50 vs 1.7%, P < .001). Six percent of patients with thermal inhalation injury develop LTS. LTS was associated with more severe thermal airway injury, longer duration of intubation, and more severe initial host inflammation. Patients with inhalation injury and LTS are at high risk for tracheostomy dependence. In burn patients with thermal inhalation injury, laryngeal evaluation and directed therapy should be incorporated early into multispecialty pathways of care.

Red blood cell distribution width and atrial fibrillation

Atrial fibrillation (AF) is the most frequent arrhythmia encountered in clinical practice and is a major health problem associated with remarkable morbidity, mortality and has considerable healthcare costs. Red blood cell distribution width (RDW) reflects the heterogeneity of the volume and size of red blood cells. It is an easily measured and inexpensive index that has been associated with several cardiovascular disease states. Accumulating evidence suggests that RDW is a prognostic marker of AF in various clinical settings. In this article, we review the available data regarding the prognostic role of RDW in AF development and perpetuation in diverse disease states as well as its role on the prediction of adverse outcomes.

Left atrium size and red cell distribution width predict atrial fibrillation progression from paroxysmal or persistent to permanent

Objective: Stratifying patients with paroxysmal or short-term persistent atrial fibrillation (AF) who are at greater risk of developing permanent AF is challenging. Aim of our prospective study was to evaluate association of laboratory parameters (biochemistry and complete blood count (CBC)) together with standard demographic, clinical and echocardiography parameters, with AF progression.Methods: We prospectively recruited 579 patients with AF and divided them into two groups at index hospitalization: paroxysmal or persistent (non-permanent AF), and long-term persistent or permanent AF patients (permanent AF). Clinical, echocardiographic, and relevant CBC parameters were collected. Non-permanent AF patients were selected for follow-up, with a median follow-up time of 21 months. Endpoint was progression to permanent AF.Results: Out of 409 patients with non-permanent AF, 109 (26.6%) progressed within follow-up. In a multivariate Cox regression model only increased left atrium (LA) diameter (HR 2.16, 95% CI 1.20-3.87, p = 0.010), and increased red cell distribution width (RDW; HR 1.19, 95% CI 1.03-1.39, p = 0.022) showed significant independent association with progression. There were 221/409 patients with both LA ≤45 mm and RDW level ≤14.5% who progressed at a rate of only 17.6%, and showed relative risk of AF progression of 0.47 (95% CI 0.34-0.67; p < 0,001).Conclusion: Together with LA size, RDW was independently associated with AF progression. Patients with both LA size ≤45 mm and RDW level ≤14.5% are most probably the best candidates for rhythm control strategies.

Association Between Red Blood Cell Distribution Width and Outcomes of Open Airway Reconstruction Surgery in Adults

Importance

Airway reconstruction for adults with laryngotracheal stenosis (LTS) is directed toward improving airway caliber to mitigate the patient's dyspnea and achieve prosthesis-free breathing (ie, without tracheostomy, intraluminal stent, or T-tube). Despite the importance of preoperative risk stratification to minimize postoperative complications, consensus on an objective predictive algorithm for open airway reconstruction is lacking.

Objective

To determine whether the ability to achieve a prosthesis-free airway in adults after open airway reconstruction is associated with red blood cell distribution width (RDW) at the time of surgery.

Design, Setting, and Participants

Case series study investigating 92 consecutive patients 18 years and older with laryngotracheal stenosis who underwent open airway reconstruction at a US tertiary care hospital from January 1, 2006, to January 1, 2017.

Main Outcomes and Measures

The main outcome was a prosthesis-free airway (absence of tracheostomy, intraluminal stent, or T-tubes) at last follow-up. Multivariate logistic regression modeling was used to identify independent factors associated with this outcome.

Results

Of the 92 patients who met inclusion criteria, the median (interquartile range) age was 44 (33.0-60.3) years; 50 (53%) were female, and 82 (89%) were white. In all, 74 patients (80%) were prosthesis free at the last follow-up (mean, 833 days; 95% CI, 10-4229 days). In multivariate analyses, airway decannulation was significantly correlated with reduced RDW (odds ratio [OR], 0.40; 95% CI, 0.19-0.84) and the absence of posterior glottic stenosis (OR, 0.12; 95% CI, 0.04-0.37).

Conclusions and Relevance

These data suggest that surgical success in open airway reconstruction is significantly associated with RDW and whether the patient had posterior glottic stenosis. The RDW is a routine laboratory parameter that may provide some insight to the preoperative probability of prosthesis removal, facilitate risk stratification, promote informed patient decision making, and optimize health care resource management.

Red blood cell distribution width: A marker of anisocytosis potentially associated with atrial fibrillation

The incorporation of biomarkers in the actually used risk scores seem to be helpful for early identifying atrial fibrillation (AF) patients at higher risk. The aim of this critical review of the scientific literature is to investigate the potential clinical significance of red blood cell distribution width (RDW) in AF. A systematic electronic search was carried out to identify all articles describing an epidemiological association between RDW and AF in adult human populations. Data abstraction was conducted on a final number of 35 articles (13 cross-sectional, 12 prospective and 10 retrospective studies). The results of these epidemiological investigations were all virtually concordant to emphasize that an enhanced RDW value is not only a predictive factor and a marker of AF but its measurement may also be helpful for predicting the risk of developing many adverse complications in patients with AF, such as recurrence and duration of AF, hospitalization for heart failure, bleeding, left atrial thrombosis and stasis, thromboembolic events and mortality. AF patients with RDW values exceeding the local reference range may be more aggressively investigated and managed, in order to identify and attenuate the impact of possible underlying disorders causing both anisocytosis and AF.

The diagnostic and prognostic value of red cell distribution width in cardiovascular disease; current status and prospective

The red blood cell distribution width (RDW) is an index of the heterogeneity of circulating red blood cell size, which along with other standard complete blood count (CBC) parameters are used to identify hematological system diseases. Besides hematological disorders, several clinical studies have shown that an increased in the RDW may be associated with other diseases including acute pancreatitis, chronic kidney disease, gastrointestinal disorders, cancer, and of special interest in this review, cardiovascular disease (CVD). The diagnostic and prognostic value of RDW in different CVD (acute coronary syndrome, ischemic cerebrovascular disease, peripheral artery disease, atrial fibrillation, heart failure, and acute ischemic stroke) has been reviewed in this article, to provide an understanding how its measurement may be applied to improve the management of these conditions.

Diagnostic and Prognostic Relevance of Red Blood Cell Distribution Width for Vascular Aging and Cardiovascular Diseases

Evidence suggests association of red blood cell distribution width (RDW) with cardiovascular diseases (CVDs). On the contrary, we underline that the sole RDW values cannot represent a valid CVD biomarker. High RDW values are expression of biological effects of a lot of both endogenous and exogenous factors (i.e., age, sex, genetic background, inflammation, hormones, drugs, diet, exercise, hematological analyzers, and ranges of values), modulating the biology and physiology of erythrocytes. Thus, the singular monitoring of RDW cannot be used to predict cardiovascular disorders. Accordingly, we have reviewed the evidence for potential relationship of RDW values with alterations in the cardiovascular system (i.e., regenerative capacity, endothelial turnover, and senescence of cardiovascular cells), associated with vascular aging and disease. In addition, we highlight the inevitable impact of biases in clinical application of RDW related to CVDs. Based on our thorough review of literature, we suggest a combined evaluation of RDW with other emerging biomarkers related to vascular aging and the diagnosis and prognosis of CVDs, including telomere length of leukocytes, circulating nucleated red blood cells (nRBCs) and endothelial progenitor cells (EPCs) in future large scale studies.

Red Cell Distribution Width and Mortality in Patients With Acute Coronary Syndrome: A Meta-Analysis on Prognosis

Background

Red cell distribution width (RDW), a routine component of the complete blood count (CBC), measures variation in the size of circulating erythrocytes. It has been associated with several clinical outcomes in cardiovascular disease. We sought to strengthen the association between RDW and mortality in patients admitted for acute coronary syndrome (ACS) by pooling together data from available studies.

Methods

Studies that fulfilled the following were identified for analysis: 1) observational; 2) included patients admitted for ACS; 3) reported data on all-cause or cardiovascular (CV) mortality in association with a low or high RDW; and 4) used logistic regression analysis to control for confounders. Using MEDLINE, Clinical Key, ScienceDirect, Scopus, and Cochrane Central Register of Controlled Trials databases, a search for eligible studies was conducted until January 9, 2017. The quality of each study was evaluated using the Newcastle-Ottawa Quality Assessment Scale. Our primary outcome of interest was all-cause or CV mortality. We also investigated the impact of RDW on major adverse cardiovascular events (MACEs) for the studies that reported these outcomes. Review Manager (RevMan) 5.3 was utilized to perform Mantel-Haenzel analysis of random effects and compute for relative risk.

Results

We identified 13 trials involving 10,410 patients, showing that in ACS, a low RDW is associated with a statistically significant lower all-cause or CV mortality (RR 0.35, (95% CI 0.30 to 0.40), P < 0.00001, I² = 53%), a finding that was consistent both in the short- and long-term.

Conclusions

A low RDW is also associated with lower risk for MACEs after an ACS (RR 0.56, (95% CI 0.51 to 0.61), P < 0.00001, I² = 91%). A low RDW during an ACS is associated with lower all-cause or CV mortality and lower risk of subsequent MACEs, providing us with a convenient and inexpensive risk stratification tool in ACS patients.

High red cell distribution width at the time of ST segment elevation myocardial infarction is better at predicting diastolic than systolic left ventricular dysfunction: A single-center prospective cohort study

Multiple studies have demonstrated the association of red cell distribution width (RDW) with the ultrasound parameters of both systolic and diastolic heart dysfunction. We aimed to further investigate the clinical associations of RDW in the setting of ST-elevation myocardial infarction (STEMI) and to comparatively evaluate its predictive properties regarding systolic and diastolic dysfunction.A total of 89 patients with STEMI were prospectively analyzed. RDW was obtained at the time of STEMI and compared to the parameters of systolic and diastolic dysfunction obtained by transthoracic heart ultrasound on the 5th through 7th day post-STEMI.The median RDW was 13.9%, and among other factors, RDW was significantly associated with older age (P < .001), arterial hypertension (P = .017), hyperlipoproteinemia 2, nonsmoking (P = .027), increased thrombolysis in myocardial infarction score (P = .004), and multivessel disease (P = .007). A higher RDW was observed in patients with parameters that indicated systolic and diastolic dysfunction (ejection fraction of the left ventricle < 50% [P = .009], early/late diastolic filling wave ratio [E/A] < 1 [P = .001], ratio of peak early transmitral velocity and early diastolic annular velocity [E/E'] >10 [P < .001], and combined E/A < 1 and E/E' > 10 [P < .001]). The best discriminatory properties were observed for combined E/A < 1 and E/E' > 10. RDW remained significantly associated with the aforementioned parameters in a series of multivariate regression models.Elevated RDW is significantly associated with the parameters of systolic and diastolic dysfunction even after adjusting for several confounding factors in the setting of STEMI and subsequent percutaneous coronary intervention. RDW seems to be better at discriminating patients with diastolic rather than systolic dysfunction.

Red blood cell distribution width as a predictor of atrial fibrillation

BACKGROUND

Current evidence suggests that a higher red blood cell distribution width (RDW) may be associated with increased risk of atrial fibrillation (AF) development. Given that some controversial results have been published, we conducted a systematic review of the current literature along with a comprehensive meta-analysis to evaluate the association between RDW and AF development.

METHODS

We performed a systematic search of the literature using electronic databases (PubMed, Ovid, Embase, and Web of Science) to identify studies reporting on the association between RDW and AF development published until June 2016. We used both fix-effects and random-effects models to calculate the overall effect estimate. An I²  > 50% indicates at least moderate statistical heterogeneity. A sensitivity analysis and subgroup analysis were performed to find the origin of heterogeneity.

RESULTS

A total of 12 studies involving 2721 participants were included in this meta-analysis. The standardized mean difference in the RDW levels between patients with and those without AF development was 0.66 units (P < .05; 95% confidence interval 0.44-0.88). A significant heterogeneity between the individual studies was observed (P < .05; I²  = 80.4%). A significant association between the baseline RDW levels and AF occurrence or recurrence following cardiac procedure or surgery was evident (SMD: 0.61; 95% confidence interval 0.33-0.88; P < .05) with significant heterogeneity across the studies (I²  = 80.7%; P < .01).

CONCLUSIONS

Our comprehensive meta-analysis suggests that higher levels of RDW are associated with an increased risk of AF in different populations.

Red Blood Cell Distribution Width: A Novel Predictive Indicator for Cardiovascular and Cerebrovascular Diseases

The red blood cell distribution width (RDW) obtained from a standard complete blood count (CBC) is a convenient and inexpensive biochemical parameter representing the variability in size of circulating erythrocytes. Over the past few decades, RDW with mean corpuscular volume (MCV) has been used to identify quite a few hematological system diseases including iron-deficiency anemia and bone marrow dysfunction. In recent years, many clinical studies have proved that the alterations of RDW levels may be associated with the incidence and prognosis in many cardiovascular and cerebrovascular diseases (CVDs). Therefore, early detection and intervention in time of these vascular diseases is critical for delaying their progression. RDW as a new predictive marker and an independent risk factor plays a significant role in assessing the severity and progression of CVDs. However, the mechanisms of the association between RDW and the prognosis of CVDs remain unclear. In this review, we will provide an overview of the representative literatures concerning hypothetical and potential epidemiological associations between RDW and CVDs and discuss the underlying mechanisms.

Relation of red blood cell distribution width with CHADS2 and CHA2DS2-VASc score in Chinese patients with non-valvular atrial fibrillation

BACKGROUND

Higher red cell distribution width (RDW) predicts adverse events in patients with cardiovascular diseases. However, there are limited data regarding the relationship between RDW and thromboembolism risk in the patients with atrial fibrillation (AF). We aimed to investigate the association between RDW and CHADS2, CHA2DS2-VASc scores used for the evaluation of thromboembolic risk in patients with non-valvular atrial fibrillation (AF).

METHODS

Our study included 99 patients with AF (68 paroxysmal AF; 31 persistent AF). We calculated CHADS₂ and CHA₂DS₂-VASc risk scores for each patient, and we carefully recorded clinical characteristics as well as laboratory and echocardiographic parameters. According to CHADS₂ and CHA₂DS₂-VASc scores, we divided the AF patients into 2 groups (low-intermediate risk and high risk group). Subsequently, we compared the aforementioned parameters between the 2 groups, and we evaluated the relationship between RDW and CHADS₂/CHA2DS₂-VASc score. Finally, multivariate logistic regression analysis was performed to find independent predictors of high CHADS₂, CHA₂DS₂-VASc scores.

RESULTS

Patients with high CHADS₂, CHA₂DS₂-VASc scores had older age, higher RDW, and creatinine levels, increased left atrial diameter and lower left ventricular ejection fraction, compared to the low CHADS₂, CHA₂DS₂-VASc score group. Multivariate logistic regression analysis showed that RDW was an independent predictor for high CHADS₂, CHA₂DS₂-VASc scores(OR: 2.184 and OR: 5.748; all P<0.05).

CONCLUSION

RDW is significantly correlated with CHADS₂ and CHA₂DS₂-VASc score in the patients with AF, while is an independent predictor for high CHADS₂ and CHA₂DS₂-VASc score.

Association of admission serum laboratory parameters with new-onset atrial fibrillation after a primary percutaneous coronary intervention

OBJECTIVES

New-onset atrial fibrillation (NOAF) during hospitalization is considered a frequent complication associated with worse outcomes in the setting of ST-segment elevation myocardial infarction (STEMI). We aimed to investigate the association of admission serum laboratory parameters, neutrophil to lymphocyte ratio (NLR), and monocyte to high-density lipoprotein ratio (MHR) with NOAF in STEMI patients treated with a primary percutaneous coronary intervention (PCI).

PATIENTS AND METHODS

A total of 621 patients who were hospitalized with a diagnosis of STEMI and treated with primary PCI were retrospectively enrolled in the study. NOAF during index hospitalization and overall mortality were reported as the clinical outcomes.

RESULTS

In our study population, 40 (6.4%) patients developed NOAF during index hospitalization. Monocyte counts, mean platelet volume (MPV), red cell distribution width (RDW), NLR, MHR, C-reactive protein (CRP), creatinine, glucose, and uric acid levels were higher in the NOAF+ group compared with the NOAF- group. In multivariate regression analysis, age, left-ventricular ejection fraction, left atrial volumes, admission heart rate, multivessel disease, increased levels of CRP, MPV, RDW, uric acid, NLR, and MHR independently predicted NOAF. In addition, NOAF was found to be an independent predictor of overall mortality in the study population.

CONCLUSION

For the first time in the literature, admission serum levels of MPV, RDW, uric acid, NLR, and MHR were found to be correlated independently with NOAF after primary PCI.

Red cell distribution width as a novel predictor for clinical outcomes in patients with paroxysmal atrial fibrillation

AIMS

Elevated red cell distribution width (RDW) has been known to be associated with adverse long-term outcomes in patients with cardiovascular diseases. We aimed to evaluate relationship between RDW values and clinical outcomes in patients with paroxysmal atrial fibrillation (AF).

METHODS AND RESULTS

We analysed 567 patients who were newly diagnosed as paroxysmal AF. Clinical outcomes were analysed after median 4.8 (3.4-6.9) years follow-up. The composite clinical outcomes were defined as the composite of death, hospitalization due to heart failure, and new-onset stroke. Bleeding events were composed of major and minor bleeding. The relationship of RDW with clinical outcomes was assessed using continuous or categorical variables as quartiles: <12.8, 12.8-13.2, 13.3-13.8, and ≥13.9%. Patients with the highest RDW quartile were the oldest and had more frequent history of heart failure. CHA2DS2-VASc score was increased along with increasing RDW quartiles (1.75 ± 1.48 vs. 1.77 ± 1.63 vs. 1.87 ± 1.61 vs. 2.33 ± 1.65, P = 0.008). Incidence of new-onset stroke (log-rank P = 0.032), the composite clinical outcomes (log-rank P = 0.014), and bleeding events (log-rank P = 0.001) were increased as increasing RDW quartiles. Multivariate analysis identified that RDW was a significant predictor for new-onset stroke [adjusted hazard ratio (HR) 1.32, 95% confidence interval (CI) 1.06-1.65, P = 0.015], the composite clinical outcomes (adjusted HR 1.21, 95% CI 1.03-1.41, P = 0.017), and bleeding events (adjusted HR 1.36, 95% CI 1.13-1.64, P = 0.001).

CONCLUSIONS

RDW can be a new, useful, novel predictor of clinical and safety outcomes in patients with paroxysmal AF.

Red blood cell distribution width and cardiovascular diseases

BACKGROUND

The red blood cell distribution width (RDW) is a rather simple measure of red blood cell (RBC) size heterogeneity (i.e., anisocytosis), which is easily calculated by dividing the standard deviation (SD) of erythrocyte volumes for the mean corpuscular volume (MCV). Emerging evidence suggests that, besides RBC abnormalities, many human disorders may be frequently associated with a high degree of anisocytosis.

METHODS

In this narrative review, we analyzed the current scientific literature about the putative role and the potential epidemiologic association between RDW and cardiovascular diseases. The findings of the most representative epidemiological studies were summarized and discussed.

RESULTS

Overall, considerable and convincing evidence has been brought that an increased RDW value is associated with acute coronary syndrome (ACS) [including acute myocardial infarction (AMI)], ischemic cerebrovascular disease (including stroke), peripheral artery disease (PAD), as well as with atrial fibrillation (AF), heart failure (HF) and hypertension. Higher anisocytosis also significantly and independently predicts adverse outcomes in patients with these conditions.

CONCLUSIONS

Although the role of anisocytosis in the pathogenesis of cardiovascular diseases remains uncertain, the considerable evidence available so far suggests that the clinical use of RDW may be broadened beyond the conventional boundaries of erythrocyte disorders, in particular for assisting the diagnosis and prognostication of patients with ACS, ischemic cerebrovascular disease, PAD, HF and AF.

SYNTAX score predicts postoperative atrial fibrillation in patients undergoing on-pump isolated coronary artery bypass grafting surgery

Objective:

Atrial fibrillation (AF) is the most common arrhythmia following coronary artery by-pass graft surgery (CABG). The value of SYNTAX score to predict postoperative atrial fibrillation (PoAF) has not been clearly addressed. We aimed to evaluate this relationship in patients undergoing isolated CABG.

Methods:

This study was designed as a single-center, non-randomized, observational, prospective study. Ninety-four patients undergoing isolated on-pump CABG, who had sinus rhythm and were older than 18 years, were enrolled. Demographic characteristics of the patients were recorded; SYNTAX score was calculated preoperatively for each patient. The univariate and multivariate logistic regression analysis were used to determine for predictors of PoAF.

Results:

The median SYNTAX score of the enrolled patients was 21, (56–5). PoAF was observed in 31 (33.3%) patients. Univariate logistic regression showed that age, chronic obstructive pulmonary disease (COPD), red blood cell distribution width (RDW), urea, initial troponin I, peak postoperative troponin I, interventricular septum, left atrial diameter, and SYNTAX score were significantly associated with the frequency of PoAF following CABG. An independent association was identified with age [b 0.088, p:0.023, OR: 1.092, 95% CI (1.012–1.179)], COPD [(b: 2.222, p:0.003, OR: 9.228, 95% CI (2.150–39.602)], and SYNTAX score [(b: 0.130, p:0.002, OR: 1.139, 95% CI (1.050–1.235)].

Conclusion:

This study showed that a higher SYNTAX score was related to more frequent PoAF in patients undergoing isolated on-pump CABG.

The Prognostic Role of Red Blood Cell Distribution Width in Coronary Artery Disease: A Review of the Pathophysiology

Red blood cell distribution width (RDW) is a measure of red blood cell volume variations (anisocytosis) and is reported as part of a standard complete blood count. In recent years, numerous studies have noted the importance of RDW as a predictor of poor clinical outcomes in the settings of various diseases, including coronary artery disease (CAD). In this paper, we discuss the prognostic value of RDW in CAD and describe the pathophysiological connection between RDW and acute coronary syndrome. In our opinion, the negative prognostic effects of elevated RDW levels may be attributed to the adverse effects of independent risk factors such as inflammation, oxidative stress, and vitamin D₃ and iron deficiency on bone marrow function (erythropoiesis). Elevated RDW values may reflect the intensity of these phenomena and their unfavorable impacts on bone marrow erythropoiesis. Furthermore, decreased red blood cell deformability among patients with higher RDW values impairs blood flow through the microcirculation, resulting in the diminution of oxygen supply at the tissue level, particularly among patients suffering from myocardial infarction treated with urgent revascularization.

Red blood cell distribution width and atrial fibrillation in patients with sick sinus syndrome

BACKGROUND

Sick sinus syndrome (SSS) is associated with atrial fibrillation (AF). Red blood cell distribution width (RDW) is a marker of anisocytosis of erythrocytes and is related to inflammatory stress. Recently, RDW has been associated with AF. The aim of the present study was to evaluate the potential association of RDW with AF history in patients with SSS.

METHODS

Consecutive patients with symptomatic SSS undergoing dual-chamber pacemaker implantation were screened. Baseline clinical, laboratory, echocardiographic, and electrocardiographic parameters were recorded. Conventional inflammatory indexes were also assessed. Multivariate logistic regression analysis and receiver operating characteristic (ROC) curve analysis for parameters associated with AF were performed.

RESULTS

The final study population consisted of 101 patients (47 men); median age: 77 [73-82] years. The demographic and clinical characteristics were comparable between tachy-brady (AF history) patients (n=32) and patients with other forms of SSS (n=69). Left atrial diameter was increased in tachy-brady patients [44 (39-48)mm vs. 39 (36-44)mm; p=0.05]. Also, the RDW was greater in these patients [14.7 (13.6-15.4)% vs. 13.7 (13.4-14.3)%; p=0.02]. Multivariate analysis showed that RDW is independently associated with AF (OR: 1.58; 95% CI: 1.06-2.85; p=0.04). The ROC curve analysis showed that the area under the curve was 0.69 (p=0.028). A RDW cut-off point of 14 was related to AF with a sensitivity of 70% and a specificity of 69%.

CONCLUSION

RDW is associated with AF history in patients with SSS. The prognostic value of RDW in terms of future AF development and arrhythmia perpetuation in these patients should be further examined.

The relationship between elevated red cell distribution width and long-term outcomes among patients with atrial fibrillation

OBJECTIVES

Red cell distribution width (RDW) is associated with the incidence of atrial fibrillation (AF). The aim of this study was to evaluate the relationship between elevated RDW and long-term clinical outcomes among patients with AF.

DESIGN AND METHODS

We prospectively observed 300 consecutive patients with AF (50.3% males, mean age 62.6 ± 12.9 years) between February 2009 and October 2011. Baseline RDW levels and clinical data were collected. The primary clinical outcomes of interest included all-cause mortality and the incidence of major adverse events (MAEs).

RESULTS

During a median follow-up period of 3.2 years, 60 deaths and 92 MAEs were recorded. From the lowest to the highest RDW quartile, an increased risk of mortality (2.76, 3.98, 8.40 and 13.77 per 100 person-years, respectively) and an incidence of MAEs (6.46, 8.18, 13.79 and 20.27 per 100 person-years, respectively) were noted. In a multivariate Cox regression analysis, RDW was independently associated with both all-cause mortality (hazard ratio (HR): 1.024; 95% confidence interval (CI): 1.012-1.036, P < 0.001) and MAEs (HR: 1.012; 95% CI: 1.002-1.023, P = 0.023). A receiver operating characteristic (ROC) analysis revealed that RDW predicted both mortality and MAEs with areas under the ROC curves (AUCs) of 0.682 (P < 0.001) and 0.617 (P = 0.001); the best cutoff points were 13.85% and 13.55%, respectively.

CONCLUSIONS

Elevated RDW is an independent predictor of long-term adverse clinical outcomes, including all-cause mortality and MAEs, among patients with AF.

Elevated levels of RDW is associated with non-valvular atrial fibrillation

Red cell distribution width (RDW) and neutrophil/lymphocyte ratio (NLR) have been found to be associated with cardiovascular diseases. Only a few trials have investigated the correlation of these parameters with postoperative atrial fibrillation (AF). However, the correlation of these parameters in non-valvular AF is still unclear. We retrospectively analyzed consecutive AF patients from medical records and included 117 non-valvular AF patients (103 paroxysmal and 14 chronic AF). All subjects underwent physical examination and echocardiographic imaging. Complete blood counts (CBCs) were analyzed for hemoglobin, RDW, neutrophil and lymphocyte counts as well as mean corpuscular volume. Results of CBC tests within the previous year were also included and the averages were used. The demographic and echocardiographic properties of non-valvular AF group were comparable to the control group except for left atrial volumes which were increased in AF (median 33.1, IQR 26.3-41.1 cm(3) vs. median 26.4, IQR 24.2-28.9 cm(3); p = 0.01). RDW levels were significantly higher in the AF group (median 13.4 %, IQR 12.9-14.1 %) compared to the control (median 12.6 %, IQR 12.0-13.1 %; p = 0.01). NLR was not statistically different in the AF group and the controls (2.04 ± 0.94 vs. 1.93 ± 0.64, respectively; p = 0.32). Hs-CRP levels were higher in the AF group compared to the controls (median 0.84, IQR 0.30-1.43 mg/L vs. median 0.29, IQR 0.18-0.50 mg/L, respectively; p = 0.01). Multivariate logistic regression analysis revealed RDW (OR 4.18, 95 % CI 2.15-8.15; p = 0.01), hs-CRP (OR 3.76, 95 % CI 1.43-9.89; p = 0.01) and left atrial volume (OR 1.31, 95 % CI 1.06-1.21; p = 0.01) as the independent markers of non-valvular AF. Multivariate linear regression analysis revealed that hemoglobin levels (standardized β coefficient = -0.252; p = 0.01) and the presence of AF (standardized β coefficient = 0.336; p = 0.01) were the independent correlates of RDW levels. Elevated RDW levels, not NLR, may be an independent risk marker for non-valvular AF.

Red blood cell distribution width: A simple parameter with multiple clinical applications

The red blood cell distribution width (RDW) is a simple and inexpensive parameter, which reflects the degree of heterogeneity of erythrocyte volume (conventionally known as anisocytosis), and is traditionally used in laboratory hematology for differential diagnosis of anemias. Nonetheless, recent evidence attests that anisocytosis is commonplace in human disorders such as cardiovascular disease, venous thromboembolism, cancer, diabetes, community-acquired pneumonia, chronic obstructive pulmonary disease, liver and kidney failure, as well as in other acute or chronic conditions. Despite some demographic and analytical issues related to the routine assessment that may impair its clinical usefulness, an increased RDW has a high negative predictive value for diagnosing a variety of disorders, but also conveys important information for short- and long-term prognosis. Even more importantly, the value of RDW is now being regarded as a strong and independent risk factor for death in the general population. Although it has not been definitely established whether an increased value of RDW is a risk factor or should only be considered an epiphenomenon of an underlying biological and metabolic imbalance, it seems reasonable to suggest that the assessment of this parameter should be broadened far beyond the differential diagnosis of anemias. An increased RDW mirrors a profound deregulation of erythrocyte homeostasis involving both impaired erythropoiesis and abnormal red blood cell survival, which may be attributed to a variety of underlying metabolic abnormalities such as shortening of telomere length, oxidative stress, inflammation, poor nutritional status, dyslipidemia, hypertension, erythrocyte fragmentation and alteration of erythropoietin function. As such, the aim of this article is to provide general information about RDW and its routine assessment, to review the most relevant implications in health and disease and give some insights about its potential clinical applications.