Preventive Effect of Preoperative Vitamin D Supplementation on Postoperative Atrial Fibrillation

Which should you choose for post operative atrial fibrillation, carvedilol or metoprolol? A systemic review and meta-analysis

BACKGROUND

Postoperative atrial fibrillation (POAF) is the most common arrhythmic complication following cardiac surgery. Current guidelines suggest beta-blockers for the prevention of POAF. In comparing metoprolol succinate with carvedilol, the later has sparked interest in its usage as an important medication for POAF prevention.

METHODS

We considered randomized controlled studies (RCTs) and retrospective studies that evaluated the efficacy of carvedilol versus metoprolol for the prevention of POAF. After literature search, data extraction, and quality evaluation, pooled data were analyzed using either the fixed-effect or random-effect model using Review Manager 5.3. The Cochrane risk of bias tool was used to assess the bias of included studies. The incidence of POAF was the primary endpoint, while mortality rate and bradycardia were secondary outcomes.

RESULTS

In meta-analysis 5 RCTs and 2 retrospective studies with a total of 1000 patients were included. The overall effect did not favor the carvedilol over metoprolol groups in terms of mortality rate [risk ratio 0.45, 95 % CI (0.1-1.97), P=0.29] or incidence of bradycardia [risk ratio 0.63, 95 % CI (0.32-1.23), P=0.17]. However, the incidence of POAF was lower in patients who received carvedilol compared to metoprolol [risk ratio 0.54, 95 % CI (0.42-0.71), P < 0.00001].

CONCLUSION

In patients undergoing cardiac surgery, carvedilol may minimize the occurrence of POAF more effectively than metoprolol. To definitively establish the efficacy of carvedilol compared to metoprolol and other beta-blockers in the prevention of POAF, a large-scale, well-designed randomized controlled trials are required.

Role of vitamin D supplementation in modifying outcomes after surgery: a systematic review of randomised controlled trials

BACKGROUND

There is increasing evidence to suggest vitamin D plays a role in immune and vascular function; hence, it may be of biological and clinical relevance for patients undergoing major surgery. With a greater number of randomised studies being conducted evaluating the impact of vitamin D supplementation on surgical patients, it is an opportune time to conduct further analysis of the impact of vitamin D on surgical outcomes.

METHODS

MEDLINE, EMBASE and the Cochrane Trials Register were interrogated up to December 2023 to identify randomised controlled trials of vitamin D supplementation in surgery. The risk of bias in the included studies was assessed using the Cochrane Risk of Bias tool. A narrative synthesis was conducted for all studies. The primary outcome assessed was overall postoperative survival.

RESULTS

We screened 4883 unique studies, assessed 236 full-text articles and included 14 articles in the qualitative synthesis, comprising 1982 patients. The included studies were highly heterogeneous with respect to patient conditions, ranging from open heart surgery to cancer operations to orthopaedic conditions, and also with respect to the timing and equivalent daily dose of vitamin D supplementation (range: 0.5-7500 mcg; 20-300 000 IU). No studies reported significant differences in overall survival or postoperative mortality with vitamin D supplementation. There was also no clear evidence of benefit with respect to overall or intensive care unit length of stay.

DISCUSSION

Numerous studies have reported the benefits of vitamin D supplementation in different surgical settings without any consistency. However, this systematic review found no clear evidence of benefit, which warrants the supposition that a single biological effect of vitamin D supplementation does not exist. The observed improvement in outcomes in low vitamin D groups has not been convincingly proven beyond chance findings.

TRIAL REGISTRATION NUMBER

CRD42021232067.

Endogenous and exogenous protection from surgically induced reactive oxygen and nitrogen species

Surgical intervention creates reactive oxygen species through diverse molecular mechanisms, including direct stimulation of immune-mediated inflammation necessary for wound healing. However, dysregulation of redox homeostasis in surgical patients overwhelms the endogenous defense system, slowing the healing process and damaging organs. We broadly surveyed reactive oxygen species that result from surgical interventions and the endogenous and/or exogenous antioxidants that control them. This study assimilates current reports on surgical sources of reactive oxygen and nitrogen species along with literature reports on the effects of endogenous and exogenous antioxidants in human, animal, and clinical settings. Although exogenous antioxidants are generally beneficial, endogenous antioxidant systems account for over 80% of total activity, varying based on patient age, sex, and health or co-morbidity status, especially in smokers, the diabetic, and the obese. Supplementation of exogenous compounds for support in surgical patients is thus theoretically beneficial, but a lack of persuasive clinical evidence has left this potential patient support strategy without clear guidelines. A more thorough understanding of the mechanisms of exogenous antioxidants in patients with compromised health statuses and pharmacokinetic profiling may increase the utility of such support in both the operating and recovery rooms.

Vitamin D and Cardiovascular Diseases: An Update

Vitamin D is a vital nutrient that plays a significant part in several physiological processes within the human body, including calcium metabolism, bone health, immune function, and cell growth and differentiation. It is obtained mainly through exposure to sunlight but can be acquired from certain foods and supplements as well. Vitamin D deficiency (VDD) could be the risk factor for cardiovascular diseases (CVDs), such as heart disease and stroke. In blood vitamin D low levels have been linked with an enhanced risk of developing CVDs. However, it is unclear whether vitamin D levels are the leading cause or consequence of these conditions. While some studies highlight that taking vitamin D supplements could decrease the risk of CVD; however, more research is required to better understand the association between vitamin D and cardiovascular health. In this review, we aimed to summarize the currently available evidence supporting the association between vitamin D and CVDs and anesthesia considerations.

Recent Advances in Association Between Vitamin D Levels and Cardiovascular Disorders

PURPOSE OF REVIEW

In this review, we discuss the evidence that vitamin D affects cardiovascular disease through interventional and observational studies and their corresponding association mechanisms. We also highlight the need for further research to definitively conclude clinical recommendations based on preliminary data and determine the extent to which vitamin D levels may impact the incidence and prognosis of major cardiovascular diseases in the future.

RECENT FINDINGS

Cardiovascular disease has long been recognized as the leading cause of morbidity and mortality worldwide, with many risk factors implicated in its pathogenesis. Vitamin D is a risk factor that, despite being known to be crucial for its role in maintaining bone health, also has several extra-skeletal effects due to vitamin D receptors in vascular smooth muscle and cardiomyocytes. Recent studies have documented a significant association between higher vitamin D levels and lower risk of each cardiovascular disease entity; 11 studies between serum vitamin D and heart failure, 7 studies between serum vitamin D and hypertension, 8 studies between serum vitamin D and coronary artery disease, and 5 studies between serum vitamin D and atrial fibrillation. More studies documenting a significant association between increased serum vitamin D and cardiovascular disease are in the context of heart failure compared to hypertension, coronary artery disease, and atrial fibrillation. Conversely, a significant association between increased serum vitamin D and a lower risk of atrial fibrillation is reported in fewer studies compared to the association of vitamin D with other cardiovascular disease entities. Although there is evidence documenting a clear significant association of vitamin D under each category, further research is still needed to definitively conclude the role of vitamin D in cardiovascular disease management.

The Management of Postoperative Atrial Fibrillation (POAF): A Systematic Review

Postoperative atrial fibrillation (POAF) refers to new-onset atrial fibrillation (AF) that develops after surgery and is associated with an increased risk of mortality and thromboembolic events. The optimal management and treatment methods for POAF complications are not yet fully established. This systematic review aimed to evaluate the various treatment and management approaches currently available in terms of their suitability, efficacy, and side effects in handling POAF incidence post-surgery. Google Scholar and PubMed electronic databases were searched extensively for relevant articles examining the various management techniques currently used to manage POAF and published between 2018 and 2023. Data were collected on the type of surgery the patients underwent, POAF definition period, intervention, and outcome of interest. Following a systematic assessment guided by the inclusion criteria, 10 of the 579 studies retrieved were included in this study, and 293,417 POAF cases were recorded. Three of these studies used different rhythm control and rate control treatments to manage POAF cases, while seven studies used various anticoagulation therapies to manage POAF incidence. For asymptomatic patients within one to three days of surgery, rate control is sufficient to manage POAF, and routine rhythm control is not needed; rhythm control should be reserved for patients who develop complications such as hemodynamic instability. Anticoagulation was performed in patients whose POAF exceeded four days after surgery. Anticoagulation was associated with an increased risk of mortality, stroke, thromboembolic events, and major bleeding in patients who underwent coronary artery bypass graft (CABG) surgery. In contrast, in a few other studies, anticoagulation treatment led to improved outcomes in patients who developed POAF. A wide range of management methods are available for POAF after different types of surgery. However, there is only limited evidence to guide the clinical practice. The data available are mainly retrospective and insufficient to accurately evaluate the efficacy of the various management methods available for POAF. Future research should make efforts to standardize the treatment for this condition.

The Possible Influence of Vitamin D Levels on the Development of Atrial Fibrillation-An Update

Atrial fibrillation (AF) is a severe and most common supraventricular arrhythmia in humans, which, if left untreated or treated ineffectively, can lead to ischemic stroke or heart failure. It has been suggested that serum vitamin D (VitD) deficiency may be one of the critical factors influencing the onset of AF, especially in the period after cardiac surgery, such as coronary artery bypass grafting. Several papers have indicated that VitD supplementation reduces the risk of AF, significantly reducing the proportion of patients between the control and study groups in both the pre- and postoperative periods. Factors that increase the risk of AF from VitD deficiency are also further indicated, and these are age, gender, weight, season or comorbidities. In addition, the cardiodepressive mechanism of VitD is not fully understood; however, it is suggested that it acts through at least two pathways. The first indicates a direct effect of VitD on atrial muscle degradation, while the second is related to the modulation of cardiovascular depression factors. Despite many reports showing correlations between no VitD concentrations on the development of AF, this topic is still widely debated and the results from these papers are still subject to doubt. Therefore, this review aims at describing in detail the problem of correlation between VitD deficiency and the development of AF associated mainly with the postoperative period, i.e., after cardiac surgery, especially pathogenesis, and results of this correlation, taking into account recent studies, limitations and future perspectives. Due to the fact that this is still a topical problem, we believe that the collection of the latest reports and a detailed description of the problem is most appropriate in this case.

Effect of vitamin D on postoperative atrial fibrillation in patients who underwent coronary artery bypass grafting: A systematic review and Meta-analysis

BACKGROUND

Vitamin D insufficiency/deficiency has been identified as a risk factor for postoperative atrial fibrillation (POAF) after coronary artery bypass grafting (CABG). This is associated with significantly increased morbidity and mortality leading to not only prolonged hospital and intensive care unit (ICU) stay, but increased risk of stroke, heart failure, dementia, and long-term atrial fibrillation. This analysis aims to evaluate the efficacy of vitamin D supplementation in preventing POAF in patients undergoing CABG.

METHODS

We searched PubMed, Cochrane Central Register of Controlled Trials and SCOPUS from inception to June 2022 for randomized controlled trials (RCTs). The outcome of interest was the incidence of POAF. Secondarily, we analyzed the length of ICU stay, length of hospital stay, cardiac arrest, cardiac tamponade, and blood transfusion. Results were pooled using a random-effect model. Three RCTs consisting of 448 patients were included.

RESULTS

Our results suggest that vitamin D significantly reduced the incidence of POAF (RR: 0.60; 95 % CI: 0.40, 0.90; p = 0.01; I² = 8 %). It was also observed that vitamin D significantly reduced the duration of ICU stay (WMD: -1.639; 95 % CI: -1.857, -1.420; p < 0.00001). Furthermore, the length of hospital stay (WMD: -0.85; 95 % CI: -2.14, 0.43; p = 0.19; I² = 87 %) was also reduced, however, the result was not significant.

CONCLUSION

Our pooled analysis suggests that vitamin D prevents POAF. Future large-scale randomized trials are needed to confirm our results.

The Role of Vitamin D Supplementation Before Coronary Artery Bypass Grafting in Preventing Postoperative Atrial Fibrillation in Patients With Vitamin D Deficiency or Insufficiency: A Systematic Review and Meta-Analysis

This study aims to evaluate the role of preoperative vitamin D supplementation before coronary artery bypass grafting (CABG) surgery in preventing postoperative atrial fibrillation (POAF) in vitamin D deficient or insufficient patients. Three randomized controlled trials (RCTs) comprising 448 subjects were selected after a detailed search was conducted on PubMed, Cochrane CENTRAL, Scopus, and Embase in December 2022. Analysis was run using RevMan (version 5.4.1; Copenhagen: The Nordic Cochrane Centre, The Cochrane Collaboration, 2014). The analysis collected risk ratio (RR) and 95% confidence interval (CI) data from the relevant studies, which were then pooled using a random effects model. A significance level of less than 0.05 (p<0.05) was considered significant. Our analysis showed that compared with the standard of care, preoperative vitamin D supplementation in vitamin D deficient and insufficient patients effectively reduced POAF after CABG surgery (RR=0.6, 95% CI=0.4-0.9, P=0.01). There was no significant difference in the duration of hospitalization between the vitamin D supplementation group compared with the control following CABG (mean difference -0.85, 95% CI -2.13 to 0.43, P = 0.19). This meta-analysis shows that preoperative vitamin D supplementation in vitamin D deficient and insufficient patients undergoing CABG can reduce the rate of POAF. As POAF is associated with many complications, providing vitamin D supplementation to individuals with a vitamin D deficiency undergoing CABG can improve long-term cardiovascular outcomes following surgery.

Gut Microbiota in Patients with Postoperative Atrial Fibrillation Undergoing Off-Pump Coronary Bypass Graft Surgery

BACKGROUND

Post-operative atrial fibrillation (POAF) is one of the most common complications of cardiac surgery. However, the underlying mechanism is not well understood. Alterations in the gut microbiota are associated with the development of atrial fibrillation (AF). The aim of this study was to explore the relationship between gut microbiota and POAF.

METHODS

Fecal samples were collected before surgery from 45 patients who underwent coronary artery bypass grafting with POAF and 90 matched patients without POAF (1:2). 16S rRNA sequencing was used to detect the microbiome profiles of 45 POAF patients and 89 matched patients (one sample in the no-POAF group was deleted owing to low quality after sequencing). Plasma 25-hydroxy vitamin D level was measured by ELISA.

RESULTS

Compared to the patients without POAF, gut microbiota composition was remarkably changed in the patients with POAF, with an increase in Lachnospira, Acinetobacter, Veillonella and Aeromonas, and a decrease in Escherichia-Shigella, Klebsiella, Streptococcus, Brevundimonas and Citrobacter. Furthermore, plasma 25-hydroxy vitamin D levels were decreased in POAF patients and negatively correlated with an abundance of Lachnospira.

CONCLUSIONS

The gut microbiota composition between patients with and without POAF is significantly different, implying that gut microbiota may play a role in the pathogenesis of POAF. Further studies are needed to fully clarify the role of gut microbiota in the initiation of AF.

Effect of Vitamin D Supplementation on Postoperative Outcomes in Cardiac Surgery Patients: A Systematic Review

Background Vitamin D deficiency is a very common occurrence in cardiac patients. It has been proved that cardiac surgery and cardiopulmonary bypass accelerate the deficiency further. The postoperative outcomes of patients deteriorate in the presence of vitamin D deficiency. Perioperative supplementation of vitamin D is the only solution to the problem. Hence, the present systematic review was conducted to derive the efficacy and safety of vitamin D supplementation on postoperative outcomes in cardiac surgery patients.

Method Publications over duration of last 10 years was searched from different database and web sites. The data from full-text research articles were analyzed for the effect on different postoperative outcomes and side effects.

Result Eight randomized control trials were retrieved on the effect of perioperative vitamin D supplementation in cardiac surgery patients and their postoperative outcomes. Six articles (75%) were found to be in favor of improvement in postoperative outcome. Two articles (25%) did not find any difference of outcome between the control and treatment group. All the studies observed the restoration of vitamin D to normal and no adverse effects from supplementation.

Conclusion Perioperative vitamin D supplementation improves the postoperative outcomes after cardiac surgery. It is effective and safe to supplement vitamin D in cardiac surgery patients.

The Pathogenesis of Cardiac Arrhythmias in Vitamin D Deficiency

The global prevalence of vitamin D deficiency is more than 20%, and the main causes include insufficient intake, reduced absorption, abnormal metabolism, or resistance to its effects. The levels of serum vitamin D appear to influence cardiovascular risk, and the mechanism involved is linked to the transient outward current and the ultrarapid delayed rectifier K+ current densities, activated through the nuclear vitamin D receptor and Akt pathway. A significant number of studies have correlated vitamin D deficiency with an increased risk of developing cardiac arrhythmias and sudden cardiac death. For this reason, the purpose of this review is to analyze the relation between vitamin D deficiency and the pathogenesis of cardiac arrhythmias. Atrial fibrillation, increased QT interval, and QT dispersion were the most common findings associated with vitamin D deficiency. Due to the heterogeneity among existing studies, further research is necessary to confirm the existing data and to analyze its relationship with other types of arrhythmias.

The effects of vitamin D supplementation on postoperative atrial fibrillation after coronary artery bypass grafting in patients with vitamin D deficiency

INTRODUCTION

Postoperative atrial fibrillation (POAF) as a common complication of coronary artery bypass grafting (CABG) surgery is associated with increased mortality and morbidity rates. Vitamin D deficiency increases the prevalence of POAF; however, the effects of vitamin D supplementation on the incidence of POAF have not yet been completely elucidated.

METHODS

In this prospective, open-label, randomized clinical trial the level of 25-hydroxy vitamin D (25(OH) D) was measured in patients undergoing CABG surgery. Patients with vitamin D insufficiency (defined as 25(OH) D level < 30 ng/ml) were included and randomly assigned to control group to receive either the general standard of care (Group A) or to study group to receive the general standard of care plus oral vitamin D₃ , 600,000 IU 5 days before surgery (Group B). The primary outcome of our study was the occurrence of POAF during the first 5 days after CABG surgery.

RESULTS

Totally, 93 patients in group B and 103 patients in group A completed the study. The occurrence of POAF was significantly lower in group B as compared to group A (9.68% vs. 20.39%, p = .038). The length of intensive care unit (ICU) stay and hospital stay were reduced in group B patients (2.21 vs. 3.86 days, p < .001 and 7.40 vs. 9.58 days, p = .022, respectively).

CONCLUSION

Our study demonstrated that vitamin D supplementation reduces the incidence of POAF, duration of ICU, and hospital stay following CABG surgery.

Vitamin D supplementation and postoperative atrial fibrillation

Vitamin D is an important vitamin that has hormone-like effects in the human body. 1,25-dihydroxy vitamin D (1,25(OH)2 D) is known as the active form of vitamin D. Activated vitamin D can affect cellular proliferation, apoptosis, cellular membrane transport, immune system, and aging through genes. Postoperative atrial fibrillation (PoAF) is an important problem that increases mortality and morbidity rates after cardiac surgery operations. Various studies have been conducted on the relationship between vitamin D and PoAF. Although there are studies in the literature showing that vitamin D supplementation reduces cardiovascular mortality and morbidity in different study types (randomized vs. observational), there are also studies showing that it has no effect on clinical outcomes. Since the subject is atrial fibrillation, the conditions of the study groups such as age, the prevalence of coronary artery disease, degree of hypertension, and lung disease should be analyzed well. On the other hand, vitamin D supplementation should be carefully determined for which patient, for how long, and at what dose.

Association Between the Circulating Level of 25-Hydroxyvitamin D and Clinical Results After Cardiac Surgery: A Meta-Analysis and Systematic Review

Background: Vitamin D (VitD) is an important pleiotropic hormone for organ systems. Studies have focused on the level of VitD, especially that of 25-hydroxyvitamin D (25-(OH)-VitD), in patients after cardiac surgery and the relationship between VitD deficiency and adverse outcomes, but the results have been inconsistent. We carried out a meta-analysis to evaluate differences in the 25-(OH)-VitD level before and after cardiac surgery, and evaluated the predictive value of 25-(OH)-VitD level in the clinical outcomes of patients undergoing cardiac surgery.

Methods: Studies related to VitD level and cardiac surgery were searched from PubMed, EMBASE, Web of Science, and Cochrane Central Register of Controlled Trials databases from inception to October 2020. We applied the Newcastle–Ottawa Scale to assess the risk of a bias in individual studies. We examined the heterogeneity and publication bias and performed subgroup analyses and sensitivity analyses.

Results: Fifteen studies were included in our analysis. The 25-(OH)-VitD level was significantly lower immediately after surgery [stand mean difference (SMD), 0.69; 95%CI (0.1, 1.28), P = 0.023] and 24-h after surgery [0.84; (0.47, 1.21), 0.000] compared with that before surgery. A higher prevalence of 25-(OH)-VitD deficiency was recorded 24 h after surgery [RR, 0.59; 95%CI (0.47, 0.73), P = 0.00]. Pooled results demonstrated a significant relationship between the preoperative 25-(OH)-VitD level and vasoactive-inotropic score (VIS) [SMD, −3.71; 95%CI (−6.32, −1.10); P = 0.005], and patients with 25-(OH)-VitD deficiency revealed a comparatively poor prognosis and severe condition after cardiac surgery [−0.80; (−1.41, −0.19), 0.01]. However, 25-(OH)-VitD deficiency was not associated with the duration of stay in the intensive care unit.

Conclusions: Cardiac surgery would leads to deficiency of 25-(OH)-VitD. And the preoperative and postoperative levels of 25-(OH)-VitD are associated with adverse events, which is eligible to work as an indicator to demonstrate clinical outcomes.

Vitamin D and Cardiovascular Disease: Current Evidence and Future Perspectives

Vitamin D deficiency is a prevalent condition, occurring in about 30–50% of the population, observed across all ethnicities and among all age groups. Besides the established role of vitamin D in calcium homeostasis, its deficiency is emerging as a new risk factor for cardiovascular disease (CVD). In particular, several epidemiological and clinical studies have reported a close association between low vitamin D levels and major CVDs, such as coronary artery disease, heart failure, and atrial fibrillation. Moreover, in all these clinical settings, vitamin deficiency seems to predispose to increased morbidity, mortality, and recurrent cardiovascular events. Despite this growing evidence, interventional trials with supplementation of vitamin D in patients at risk of or with established CVD are still controversial. In this review, we aimed to summarize the currently available evidence supporting the link between vitamin D deficiency and major CVDs in terms of its prevalence, clinical relevance, prognostic impact, and potential therapeutic implications.

Vitamin D Treatment Attenuates Heart Apoptosis After Coronary Artery Bypass Surgery: A Double-Blind, Randomized, Placebo-Controlled Clinical Trial

BACKGROUND

Vitamin D plays an important role in immune system and in the regulation of inflammatory cytokines. Coronary artery bypass graft (CABG) with cardiopulmonary bypass (CPB) is associated with an extensive inflammatory response. The aim of this study is to examine the effect of vitamin D treatment on the apoptosis and inflammatory changes developed after CABG.

METHODS

This trial was conducted on 70 patients undergoing CABG with CPB. Patients were randomly administered either in placebo or in the group of orally consuming 150 000 IU vitamin D daily for 3 consecutive days before surgery. The right atrium sample was taken to assess caspases 2, 3, and 7 activity using immunohistochemistry method. The serum level of interleukin-10 (IL-10) and insulin-like growth factor 1 (IGF-1) were compared at intervals.

RESULTS

The average number of positive cells for caspases 2 and 3 were less in vitamin D group (P = .006 and P < .001, respectively). There was an increase in serum levels of IL-10 after 3 days from vitamin D treatment before surgery (vitamin D group = 4.4 ± 4.9 ng/mL and control group = 1 ± 0.5 ng/mL, P = .001). After operation, IL-10 increased in both groups, higher level in vitamin D group (P < .001). The comparison of serum IGF-1 showed significant difference after 3 days (P = .006) and remained higher in vitamin D group after CPB (P < .001).

CONCLUSIONS

These findings suggest the apoptosis rate after CPB can be reduced by vitamin D. Vitamin D treatment may improve the inflammatory status before and after surgery. Further studies are needed to confirm the antiapoptotic property of vitamin D and clinical implication.

Is there any link between vitamin D deficiency and vasovagal syncope?

BACKGROUND

This study aimed to investigate serum 25[OH]D levels between patients with vasovagal syncope (VVS) diagnosed with head-up tilt table test (HUTT) and age-matched healthy people.

METHODS

The study included 75 consecutive patients (32.3 ± 10.7 years), who presented with syncope and underwent HUTT and 52 healthy controls (32.9 ± 14.1 years). HUTT patients were divided into two groups according to whether there was syncope response to the test. Patients underwent cardiac, psychiatric, and neurological investigation. Serum 25[OH]D levels were measured by chemiluminescent microparticle immunoassay method.

RESULTS

There was no difference between the two groups in terms of age, gender, body mass index (BMI), echocardiographic findings (P > .05). Mean serum 25[OH]D (24.5 ± 6.3 vs 20.1 ± 8.8 ng/mL, P = .003) and vitamin B12 levels (436.4 ± 199.2 vs 363.1 ± 107.6 pg/mL, P = .009) was lower in syncope patients when compared to the control group. In correlation analyses, syncope was shown as correlated with the vitamin D (r = -264, P = .003) and vitamin B12 levels (r = -233, P = .009). But, multivariate regression analyses showed that only vitamin D increased risk of syncope [OR: 0.946, 95% CI (0.901-0.994)]. There was no difference in terms of age, gender, BMI, echocardiographic findings between the in HUTT positive (n = 45) and negative groups (n = 29). Only vitamin D level was significantly lower in HUTT positive group (17.5 ± 7.7 vs 24.4 ± 9.1 ng/mL, P = .002). There was no difference among in the vasovagal subgroups in terms of vitamin D level and other features.

CONCLUSION

Vitamin D and B12 levels were reasonably low in syncope patients, but especially low Vitamin D levels were associated with VVS diagnosed in HUTT.

Is there any Link Between Vitamin D and Recurrence of Atrial Fibrillation after Cardioversion?

Introduction

Atrial fibrillation (AF) is the most common chronic arrhythmia in the elderly population. In symptomatic patients, restoration and maintenance of sinus rhythm improve quality of life. Unfortunately, AF recurrence still occurs in a considerable number of patients after cardioversion (CV). In this study, we aimed to evaluate the association between vitamin D (VitD) and AF recurrence after electrical or medical CV.

Method

A total of 51 patients who underwent CV for symptomatic AF were included in the study. AF recurrence was defined as an AF pattern in 12-lead electrocardiography (ECG) recording after CV within 6 months or ECG Holter recording of AF lasting more than 30 seconds at 6-month follow-up.

Results

Mean vitD level was 21.4 ng/ml in our study population. VitD level was lower in the AF recurrence group than in the non-recurrence group (18 ng/ml vs. 26.3 ng/ml, respectively; P=0.001). Additionally, left atrial diameter was larger in the AF recurrence group compared to the non-recurrence group (4.4 vs. 4.1, P=0.025). Patients with AF recurrence were older than patients without AF recurrence, and, although the prevalence of hypertension is higher in the AF recurrence group, there was no statistically significant difference (P=0.107, P=0.867).

Conclusion

In our study, there is a strong association between vitD level and AF recurrence after CV. VitD deficiency might be a predictor of high risk of AF recurrence after CV and vitD supplementation during the follow-up might help the maintenance of sinus rhythm.

Atrial fibrillation after cardiac surgery and preoperative vitamin D levels: A systematic review and meta-analysis

Background

In this meta-analysis, we aimed to investigate the possible relationship between atrial fibrillation development after cardiac surgery and preoperative vitamin D levels.

Methods

Literature review was carried out in the PubMed, ScienceDirect and Ovid electronic databases without any limitation of time frame. Published studies which recorded the preoperative levels of vitamin D and atrial fibrillation after cardiac surgery in the English language were included. The results of the studies were evaluated based on either random or fixed effect model according to the presence of heterogeneity (I²>25%).

Results

A total of 1,865 articles were screened. After the article titles and abstracts were analyzed, six articles involving 769 patients which met the inclusion criteria were included. The results indicated that there was a relationship between preoperative vitamin D levels and postoperative atrial fibrillation (SMD: -0.46, 95% CI: -0.79 to -0.12; p<0.007). Heterogeneity was observed for studies conducted (I² =76.1%).

Conclusion

We concluded that low preoperative vitamin D levels were associated with the development of atrial fibrillation after cardiac surgery. However, there is a need for large-scale, randomized-controlled trials for preventing the heterogeneity of the results.

The Status and Research Progress on Vitamin D Deficiency and Atrial Fibrillation

Atrial fibrillation is a common type of arrhythmia and is an important cause of stroke and heart failure. vitamin D is an emerging risk factor of AF, and is implicated in the pathophysiology of atrial fibrillation. It has been established that this vitamin is extensively involved in the regulation of both the renin angiotensin aldosterone system and the immune system. Epidemiological studies have not yet reached a consensus on the possible association between vitamin D deficiency and atrial fibrillation. Better research designs and methods can further clarify the relationship between the two.

Effects of high-dose vitamin D supplementation on the occurrence of post-operative atrial fibrillation after coronary artery bypass grafting: randomized controlled trial

OBJECTIVE

This study aimed to investigate the preventive effects of a high-dose vitamin D administered preoperatively on the post-operative atrial fibrillation (POAF) occurrence in patients with insufficient or deficient serum vitamin D levels who underwent coronary artery bypass grafting (CABG) surgery.

METHODS

The study was a randomized controlled, blinded and parallel-arm trial conducted on 116 who had vitamin D deficiency or insufficiency during the pre-operative evaluation were included in the study conducted between January 2018 and January 2019. Patients were divided into those who received oral vitamin D (treatment group; n = 58) and those who did not (control group; n = 58) 48 h before CABG surgery. In the treatment group, patients with vitamin D deficiency were administered 300.000 IU vitamin D orally and those with vitamin D insufficiency 150.000 IU 48 h preoperatively. Patients were followed up during hospitalisation process with respect to POAF.

RESULTS

Both groups showed no significant differences with regard to age, gender, body mass index, creatine level, left atrial diameter, pre-operative drug use, calcium level, ejection fraction, diabetes mellitus and hypertension. The ratio of POAF occurrence found in the treatment and control groups were 12.07% and 27.59%, respectively. Vitamin D treatment was found to reduce the risk of POAF development by 0.24 times (p = 0.034).

CONCLUSION

In this study with sufficient sample size, preoperative short-term high-dose vitamin D supplementation was found to be significantly preventive to the occurrence of POAF in patients with vitamin D insufficiency and deficiency who underwent CABG surgery.

Vitamin D with calcium supplementation and risk of atrial fibrillation in postmenopausal women

BACKGROUND

Atrial fibrillation (AF) is the most common arrhythmia in adults. Although vitamin D deficiency is associated with AF risk factors, retrospective studies of association with AF have shown mixed results. We sought to determine the efficacy of calcium and vitamin D (CaD) supplementation for AF prevention in a randomized trial.

METHODS

We performed a secondary analysis of the Women's Health Initiative trial on CaD supplementation versus placebo. We linked participants to their Medicare claims to ascertain incident AF.

RESULTS

Among 16,801 included participants, there were 1,453 (8.6%) cases of incident AF over an average of 4.5 years, at an average rate of 19.9 events per 1,000 person-years. We found no significant difference in incident AF rates between the CaD and placebo arms (hazard ratio 1.02 for CaD vs placebo, 95% CI 0.92-1.13). After multivariate adjustment, there was no significant association between baseline 25-hydroxyvitamin D serum levels and incident AF (hazard ratio 0.92 for lowest subgroup vs highest subgroup, 95% CI 0.66-1.28).

CONCLUSIONS

We present the first analysis of a large randomized trial of daily vitamin D supplementation for AF prevention. We found that CaD had no effect on incidence of AF in Women's Health Initiative CaD trial participants. We also found that baseline serum 25-hydroxyvitamin D level was not predictive of long-term incident AF risk.