NT-proBNP, but not ANP and C-reactive protein, is predictive of paroxysmal atrial fibrillation in patients undergoing pulmonary vein isolation

No Detectable Differences in microRNA Plasma Levels between Diabetic Hypertensive Patients with and without Incident Subclinical Atrial Fibrillation

Background: Long-term rhythm monitoring (LTRM) can detect undiagnosed atrial fibrillation (AF) in patients at risk of AF and stroke. Circulating microRNAs (miRNAs), which have been shown to play a role in atrial electrical and structural remodelling, could help to select patients who would benefit most from LTRM. The aim of this study was to investigate whether patients with diabetes mellitus (DM) and hypertension and screen-detected subclinical AF (SCAF) using an insertable cardiac monitor (ICM) have significantly different plasma baseline levels of five selected miRNAs playing a role in the modulation of atrial electrical and structural remodelling (miR-21-5p, miR-29b-3p, miR-150-5p, miR-328-3p, and miR-432-5p) compared to those without SCAF. Methods: This study was performed at the outpatient clinic of a secondary academic teaching hospital between December 2013 and November 2015. Eligible patients were ≥65 years of age with DM and hypertension but without known heart diseases. All patients received an ICM. On the day of ICM implantation, blood samples for the measurement of plasma levels of the five miRNAs were drawn. In this post hoc analysis, we investigated their expression by reverse transcription-quantitative polymerase chain reaction. MiRNA plasma levels in patients with and without newly detected SCAF were compared. Results: We included 82 consecutive patients (median age of 71.3 years (IQR 67.4-75.1)), who were followed for a median of 588 days (IQR: 453-712 days). Seventeen patients (20.7%) had ICM-detected SCAF. Plasma levels of miR-328-3p, miR-29b-3p, miR-21-5p, miR-432-5p, and miR-150-5p were slightly but not significantly different in patients with incident SCAF compared with patients without. Conclusions: In patients with hypertension and DM, newly detected SCAF was not significantly associated with changes in expression levels of miR-21-5p, miR-29b-3p, miR-150-5p, miR-328-3p, and miR-432-5p.

Association of Preablation Plasma Corin Levels With Atrial Fibrillation Recurrence After Catheter Ablation: A Prospective Observational Study

BACKGROUND

We assessed the impact of pre- and postprocedural plasma corin levels on the recurrence of atrial fibrillation (AF) after catheter ablation (CA).

METHODS AND RESULTS

This prospective, single-center, observational study included patients undergoing their first CA of AF. Corin was measured before and 1 day after CA. The primary end point was recurrent AF between 3 and 12 months after ablation. From April 2019 through May 2021, we analyzed 616 patients with AF (59.09% men) with a mean age of 62.86±9.42 years. Overall, 153 patients (24.84%) experienced recurrent AF. In the recurrence group, the pre- and postprocedure corin concentrations were 539.14 (329.24-702.08) and 607.37 (364.50-753.80) pg/mL, respectively, which were significantly higher than the nonrecurrence group's respective concentrations of 369.05 (186.36-489.28) and 489.12 (315.66-629.05) pg/mL (both P<0.0001). A multivariate Cox regression analysis with confounders found that elevated preablation corin levels were significantly associated with an increased risk of AF recurrence after CA. Receiver operating characteristic curve analysis identified that a preablation corin threshold of >494.85 pg/mL predicted AF recurrence at 1 year. An increase of 1 SD in corin concentrations before CA (264.94 pg/mL) increased the risk of recurrent AF by 54.3% after adjusting for confounding variables (hazard ratio, 1.465 [95% CI, 1.282-1.655]; P<0.0001).

CONCLUSIONS

Plasma corin levels at baseline is a valuable predictor of AF recurrence after CA, independent of established conventional risk factors. Risk stratification before ablation for AF may be useful in selecting treatment regimens for patients.

High sensitivity C reactive protein levels and atrial fibrillation recurrence after catheter ablation for atrial fibrillation: A systematic review and meta-analysis

Background

Atrial fibrillation (AF) recurrence after AF ablation is not uncommon. High sensitivity C reactive protein (hs-CRP) is a widely used inflammatory marker with a potential property to predict AF recurrence. We conducted a systematic review and a meta-analysis to find an association between hs-CRP levels and AF recurrence after ablation.

Methods

We searched PubMed, Embase, and Wiley-Cochrane Library from inception to January 2022 for studies that reported hs-CRP levels in patients who underwent AF ablation. Weighted mean difference (WMD) was used to evaluate the difference between hs-CRP levels in post-ablation AF recurrent and non-recurrent group. Also, the difference between hs-CRP levels in pre- and post-ablation was determined.

Results

We identified 10 studies, and a total of 789 patients were included (299 recurrent vs. 490 non-recurrent patients). The mean age was 57.7 years (76.4% male). There was no difference in baseline hs-CRP levels between AF recurrent and non-recurrent group (WMD = 0.05, 95% CI = -0.04 to 0.15, p = 0.045). However, higher hs-CRP levels post-ablation were found in AF recurrent group (WMD = 0.09, 95% CI = 0.03-0.15, p < 0.001).

Conclusion

There is no significant difference in baseline hs-CRP levels between AF recurrent and non-recurrent patients after AF ablation. However, higher post-ablation hs-CRP level was found in AF recurrent group. High Sensitivity C reactive protein may play a role as a predictor of AF recurrence.

Biomarkers of Atrial Fibrillation Recurrence in Patients with Paroxysmal or Persistent Atrial Fibrillation Following External Direct Current Electrical Cardioversion

Atrial fibrillation (AF) is associated with atrial remodeling, cardiac dysfunction, and poor clinical outcomes. External direct current electrical cardioversion is a well-developed urgent treatment strategy for patients presenting with recent-onset AF. However, there is a lack of accurate predictive serum biomarkers to identify the risks of AF relapse after electrical cardioversion. We reviewed the currently available data and interpreted the findings of several studies revealing biomarkers for crucial elements in the pathogenesis of AF and affecting cardiac remodeling, fibrosis, inflammation, endothelial dysfunction, oxidative stress, adipose tissue dysfunction, myopathy, and mitochondrial dysfunction. Although there is ample strong evidence that elevated levels of numerous biomarkers (such as natriuretic peptides, C-reactive protein, galectin-3, soluble suppressor tumorigenicity-2, fibroblast growth factor-23, turn-over collagen biomarkers, growth differential factor-15) are associated with AF occurrence, the data obtained in clinical studies seem to be controversial in terms of their predictive ability for post-cardioversion outcomes. Novel circulating biomarkers are needed to elucidate the modality of this approach compared with conventional predictive tools. Conclusions: Biomarker-based strategies for predicting events after AF treatment require extensive investigation in the future, especially in the presence of different gender and variable comorbidity profiles. Perhaps, a multiple biomarker approach exerts more utilization for patients with different forms of AF than single biomarker use.

Natriuretic peptides as predictors for atrial fibrillation recurrence after catheter ablation: A meta-analysis

BACKGROUND

Catheter ablation (CA) has become the first-line treatment strategy for atrial fibrillation (AF) but remains with a substantial recurrence rate. The aim of this meta-analysis was to determine the association between baseline natriuretic peptide levels and AF recurrence after CA.

METHODS

We systematically searched PubMed, EMBASE, Web of Science, and Wiley-Cochrane Library for relevant studies published up until May 2022. Overall effect analysis and subgroup analysis were performed with Review Manager software.

RESULTS

Finally, 61 studies that met the inclusion criteria were included in our meta-analysis. Compared with the nonrecurrence group, the recurrence group had increased baseline level of atrial natriuretic peptide (ANP) (standardized mean difference [SMD] = 0.39, 95% confidence interval [CI]: 0.21-0.56), brain natriuretic peptide (BNP) (SMD = 0.51, 95% CI: 0.31-0.71), N-terminal pro-BNP (SMD = 0.71, 95% CI: 0.49-0.92), and midregional N-terminal pro-ANP (SMD = 0.91, 95% CI: 0.27-1.56).

CONCLUSIONS

Increased baseline natriuretic peptide levels, including ANP, BNP, N-terminal pro-BNP, and midregional N-terminal pro-ANP, are associated with a higher risk of AF recurrence after CA. Nonetheless, further studies are needed to elucidate the predictive value of baseline natriuretic peptides in AF patients undergoing CA.

Biomarkers associated with rhythm status after cardioversion in patients with atrial fibrillation

Biomarkers may help to improve our knowledge about the complex pathophysiology of atrial fibrillation (AF). In this study we sought to identify significant changes in biomarkers and clinical measures in patients with and without AF recurrence after electrical cardioversion. We measured 21 conventional and new biomarkers before and 30 days after electrical cardioversion and assessed the associations of changes in biomarker levels with rhythm status at follow-up. Significant between-group changes were observed for bone morphogenetic protein 10 (BMP10), N-terminal pro-B-type natriuretic peptide (NT-proBNP) and total bilirubin. Their respective changes were - 10.4%, - 62.0% and - 25.6% in patients with sinus rhythm, and 3.1%, 1.1% and - 9.4% in patients with recurrent AF, for a between-group difference of - 13.5% (95% confidence interval [CI] - 19.3% to - 7.6%; P < 0.001), - 63.1% (95% CI - 76.6% to - 49.6%; P < 0.001) and - 16.3% (95% CI - 27.9% to - 4.7%; P = 0.007). In multivariable models, the reductions of BMP10 and NT-proBNP were significantly associated with follow-up rhythm status (β coefficient per 1 - SD decrease, - 3.85; 95% CI - 6.34 to - 1.35; P = 0.003 for BMP10 and - 5.84; 95% CI - 10.22 to - 1.47; P = 0.009 for NT-proBNP. In conclusion, changes in BMP10 und NT-proBNP levels were independently associated with rhythm status after cardioversion, suggesting that these markers may be dependent on the actual heart rhythm.

Biomarkers as predictors of recurrence of atrial fibrillation post ablation: an updated and expanded systematic review and meta-analysis

Background

A high proportion of patients undergoing catheter ablation (CA) for atrial fibrillation (AF) experience recurrence of arrhythmia. This meta-analysis aims to identify pre-ablation serum biomarker(s) associated with arrhythmia recurrence to improve patient selection before CA.

Methods

A systematic approach following PRISMA reporting guidelines was utilised in libraries (Pubmed/Medline, Embase, Web of Science, Scopus) and supplemented by scanning through bibliographies of articles. Biomarker levels were compared using a random-effects model and presented as odds ratio (OR). Heterogeneity was examined by meta-regression and subgroup analysis.

Results

In total, 73 studies were identified after inclusion and exclusion criteria were applied. Nine out of 22 biomarkers showed association with recurrence of AF after CA. High levels of N-Terminal-pro-B-type-Natriuretic Peptide [OR (95% CI), 3.11 (1.80–5.36)], B-type Natriuretic Peptide [BNP, 2.91 (1.74–4.88)], high-sensitivity C-Reactive Protein [2.04 (1.28–3.23)], Carboxy-terminal telopeptide of collagen type I [1.89 (1.16–3.08)] and Interleukin-6 [1.83 (1.18–2.84)] were strongly associated with identifying patients with AF recurrence. Meta-regression highlighted that AF type had a significant impact on BNP levels (heterogeneity R² = 55%). Subgroup analysis showed that high BNP levels were more strongly associated with AF recurrence in paroxysmal AF (PAF) cohorts compared to the addition of non-PAF patients. Egger’s test ruled out the presence of publication bias from small-study effects.

Conclusion

Ranking biomarkers based on the strength of association with outcome provides each biomarker relative capacity to predict AF recurrence. This will provide randomised controlled trials, a guide to choosing a priori tool for identifying patients likely to revert to AF, which are required to substantiate these findings.

Graphical abstract

Supplementary Information

The online version contains supplementary material available at 10.1007/s00392-021-01978-w.

Biomarkers in the clinical management of patients with atrial fibrillation and heart failure

Atrial fibrillation (AF) and heart failure (HF) are two cardiovascular diseases with an increasing prevalence worldwide. These conditions share common pathophysiologiesand frequently co-exit. In fact, the occurrence of either condition can 'cause' the development of the other, creating a new patient group that demands different management strategies to that if they occur in isolation. Regardless of the temproral association of the two conditions, their presence is linked with adverse cardiovascular outcomes, increased rate of hospitalizations, and increased economic burden on healthcare systems. The use of low-cost, easily accessible and applicable biomarkers may hasten the correct diagnosis and the effective treatment of AF and HF. Both AF and HF effect multiple physiological pathways and thus a great number of biomarkers can be measured that potentially give the clinician important diagnostic and prognostic information. These will then guide patient centred therapeutic management. The current biomarkers that offer potential for guiding therapy, focus on the physiological pathways of miRNA, myocardial stretch and injury, oxidative stress, inflammation, fibrosis, coagulation and renal impairment. Each of these has different utility in current clinincal practice.

Circulating biomarkers, echocardiographic parameters, and incident subclinical atrial fibrillation in patients with diabetes and hypertension

BACKGROUND

Long-term rhythm monitoring (LTRM) can detect undiagnosed atrial fibrillation (AF) in patients at high risk of AF and stroke. Biomarkers and echocardiographic parameters could, however, help identify patients benefitting most from LTRM. The aim of this study was to investigate, whether circulating biomarkers of cardiac and vascular function (brain natriuretic peptide (BNP), cardiac troponin I (cTnI), copeptin, and mid-regional proadrenomedullin (MR-proADM)) and echocardiographic parameters were associated with incident subclinical AF (SCAF) in a population at high risk of stroke in the presence of AF. For this purpose, we investigated individuals ≥65 years of age with hypertension and diabetes mellitus, but no history or symptoms of AF or other cardiovascular disease (CVD).

METHODS

We included 82 consecutive patients (median age 71.3 years (IQR 67.4-75.1)). All patients received an insertable cardiac monitor (ICM) and were followed for a median of 588 days (IQR 453-712). On the day of ICM implantation, a comprehensive echocardiogram and blood samples were obtained.

RESULTS

During a median follow-up of 588 days (IQR: 453-712 days), incident SCAF occurred in 17 patients (20.7%) with a median time to first-detected episode of 91 days (IQR 41-251 days). MR-proADM (median 0.87 nmol/L (IQR 0.76-1.02) vs 0.78 nmol/L (IQR 0.68-0.98)) and copeptin (median 13 pmol/L (IQR 9-17) vs 8 pmol/L (IQR 4-18)) levels were insignificantly higher in patients with incident SCAF. BNP and cTnI concentrations and echocardiographic parameters were similar in the two groups.

CONCLUSIONS

MR-proADM, BNP, cTnI, copeptin, and several echocardiographic parameters were not associated with incident SCAF in this cohort of patients with hypertension and diabetes, but without any underlying CVD.

Relationship between serum angiopoietin-like 4 levels and recurrence of atrial fibrillation

Objective

To investigate the association between serum angiopoietin-like 4 (ANGPTL4) levels and recurrence of atrial fibrillation (AF) after catheter ablation.

Methods

This retrospective study recruited patients with AF undergoing catheter ablation and they were divided into two groups (new-onset AF group and recurrent AF group). Demographic, clinical, and laboratory parameters were collected.

Results

A total of 192 patients with AF were included, including 69 patients with recurrence of AF. Serum ANGPTL4 levels were lower in patients with recurrent AF than in those with new-onset AF. Serum ANGPTL4 levels were positively correlated with superoxide dismutase and peroxisome proliferator-activated receptor γ, and negatively correlated with the CHA2DS2-VASC score, left atrial diameter, and levels of brain natriuretic peptide, malondialdehyde, high-sensitivity C-reactive protein, and interleukin-6. The receiver operating characteristic curve showed that the best cut-off for recurrent AF was serum ANGPTL4 levels  < 19.735 ng/mL, with a sensitivity and specificity of 63.9% and 74.5%, respectively. Serum ANGPTL4 levels were significantly associated with recurrence and new onset of AF (odds ratio, 2.241; 95% confidence interval, 1.081–4.648).

Conclusions

Serum ANGPTL4 levels are lower in patients with recurrent AF than in those with new-onset AF, and are associated with cardiac hypertrophy, oxidative stress, and inflammation.

C-reactive protein for prediction of atrial fibrillation recurrence after catheter ablation

BACKGROUND

Inflammation plays an important role in the initiation and progression of atrial fibrillation (AF), but data about the relationship between subclinical inflammation and recurrence of AF after catheter ablation remains poorly studied. We aimed to assess whether plasma levels of C-reactive protein (CRP) are associated with long-term AF recurrence following catheter ablation.

METHODS

Prior to the intervention, plasma CRP concentrations were measured in patients who underwent first catheter ablation for AF. AF recurrence was evaluated after 12 months and defined as any AF episode longer than 30 s recorded on either 12-lead electrocardiogram, 24-h Holter or 7-day Holter monitoring. Multivariable adjusted Cox models were constructed to examine the association of CRP levels and AF recurrence.

RESULTS

Of the 711 patients (mean age: 61 years, 25% women) included in this study, 247 patients (35%) experienced AF recurrence after ablation. Patients who were in the highest CRP quartile had a higher rate of recurrent AF compared to those who were in the lowest quartile (53.4 vs. 33.1% at 1 year of follow-up; P = 0.004). The adjusted hazard ratios (aHR) of recurrent AF across increasing quartiles of CRP were 1.0 (reference), 1.26 (95% confidence interval [CI], 0.86-1.84), 1.15 (95% CI, 0.78-1.70) and 1.60 (95% CI, 1.10-2.34) (P trend = 0.015). A similar effect was observed when CRP was analyzed as continuous variable (aHR per unit increase, 1.21; 95% CI, 1.05-1.39; P = 0.009). When a predefined CRP cut-off of 3 mg/l was applied, patients with CRP levels of 3 mg/l or above had a higher risk of AF recurrence than those with levels below (aHR, 1.44; 95% CI, 1.06-1.95; P = 0.019).

CONCLUSIONS

Increasing pre-interventional CRP levels are associated with a higher risk of AF recurrence in patients undergoing catheter ablation for AF.

TRAIL REGISTRATION

ClinicalTrials.gov identifier, NCT03718364.

Predictive Role of BNP/NT-proBNP in Non-Heart Failure Patients Undergoing Catheter Ablation for Atrial Fibrillation: An Updated Systematic Review

Atrial Fibrillation (AF) is a growing public health issue, associated with significant morbidity and mortality. In addition to pharmacological therapy, catheter ablation is an effective strategy in restoring and maintaining sinus rhythm. However, ablation is not without risk, and AF recurs in a significant proportion of patients. Non-invasive, easily accessible markers or indices that could stratify patients depending on the likelihood of a successful outcome following ablation would allow us to select the most appropriate patients for the procedure, reducing the AF recurrence rate and exposure to potentially life-threatening risks. There has been much attention paid to Brain Natriuretic Peptide (BNP) and N-Terminal prohormone of Brain Natriuretic Peptide (NT-proBNP) as possible predictive markers of successful ablation. Several studies have demonstrated an association between higher pre-ablation levels of these peptides, and a greater likelihood of AF recurrence. Therefore, there may be a role for measuring brain natriuretic peptides levels when selecting patients for catheter ablation.

Thymoquinone attenuates doxorubicin-cardiotoxicity in rats

Contrary to the fact that doxorubicin is a powerful chemotherapeutic agent for the treatment of neoplastic diseases, cardiotoxicity is too important to be ignored. Thymoquinone serves as a powerful free radical scavenger. In the study, the effects of thymoquinone against doxorubicin-cardiotoxicity will be evaluated. Forty rats were divided into five groups. Group I: control group (n = 8); group II: olive oil group (n = 8); group III: thymoquinone group (n = 8); given 10 mg/kg thymoquinone intraperitoneally per day throughout the experiment; group IV: doxorubicin group (n = 8); injected with a single dose of 15 mg/kg ip doxorubicin on the 7th day of the experiment; group V: doxorubicin + thymoquinone group (n = 8); administered with 10 mg/kg thymoquinone per day during the experiment and 15 mg/kg doxorubicin ip on the 7th day. The experiment was planned for 14 days. Immunohistochemically, heat shock protein (HSP) 70 and HSP90, glucose-regulated protein 78 (GRP78), caspase-3 were stained. We made terminal deoxynucleotidyl transferase dUTP nick end labeling for apoptotic evaluation. Total oxidant status (TOS) levels and total antioxidant status (TAS) were measured in the heart tissue. Atrial natriuretic peptide (ANP) and pro-B type natriuretic peptide (proBNP) were evaluated. In the study, HSP70, HSP90, GRP78, and caspase-3 levels increased in group IV. TOS and TAS levels were significant compared to group I. Doxorubicin significantly increased ANP and NT-proBNP levels. Thymoquinone revealed significant differences in these values. Thymoquinone can be an important cardioprotective agent against doxorubicin-cardiotoxicity.

Echocardiographic and Biochemical Factors Predicting Arrhythmia Recurrence After Catheter Ablation of Atrial Fibrillation-An Observational Study

Background: RFA is a well-established treatment for symptomatic patients with AF. However, the success rate of a single procedure is low. We aimed to investigate the association between the risk of recurrence of atrial fibrillation (AF) after a single radiofrequency ablation (RFA) procedure and cardiac neurohormonal function, left atrial (LA) mechanical function as well as proteins related to inflammation, fibrosis, and apoptosis.

Methods and Results: We studied 189 patients undergoing RFA between January 2012 and April 2014, with a follow-up period of 12 months. A logistic regression analysis was performed to investigate the association between pre-ablation LA emptying fraction (LAEF), MR-proANP, Caspase-8 (CASP8), Neurotrophin-3 (NT3), and the risk for recurrence of AF after a single RFA procedure. 119 (63.0%) patients had a recurrence during a mean follow-up of 402 ± 73 days. An increased risk of recurrence was associated with: Elevated MR-proANP (fourth quartile vs. first quartile: HR, 2.80 (95% CI, 1.14–6.90]; P = 0.025); Low LAEF (fourth quartile vs. first quartile: hazard ratio [HR], 2.41 [95% CI, 1.01–5.79]; P = 0.045); Elevated CASP8 (fourth quartile vs. first quartile: HR 12.198 95% CI 2.216–67.129; P = 0.004); Elevated NT-3 (fourth quartile vs. first quartile: HR 7.485 95% CI 1.353–41.402; P = 0.021). In a receiver operating characteristic curve analysis, the combination of MR-proANP, CASP8, and NT3 produced an area under the curve of 0.819; CI 95% (0.710–0.928).

Conclusions: Patients with better LA mechanical function and lower levels of atrial neurohormones as well as of proteins related to fibrosis and apoptosis, have a better outcome after an RFA procedure.

Unique identifier: No. NCT01553045 (https://clinicaltrials.gov/ct2/show/NCT01553045?term=NCT01553045&rank=1).

Clinical Applications of Natriuretic Peptides in Heart Failure and Atrial Fibrillation

Natriuretic peptides (NPs) have become important diagnostic and prognostic biomarkers in cardiovascular diseases, particularly in heart failure (HF). Diagnosis and management of coronary artery disease and atrial fibrillation (AF) can also be guided by NP levels. When interpreting NP levels, however, the caveat is that age, sex, body mass index, renal dysfunction, and race affect the clearance of NPs, resulting in different cut-off values in clinical practice. In AF, NP levels have been associated with incident AF in the general population, recurrences after catheter ablation, prediction of clinical prognosis, and the risk of stroke. In this article, we first review and summarize the current evidence and the roles of B-type NP and atrial NP in HF and coronary artery disease and then focus on the increasing utility of NPs in the diagnosis and management of and the research into AF.

Biomarkers in Atrial Fibrillation and Heart Failure

Atrial fibrillation (AF) is the most common sustained arrhythmia encountered in clinical practice and an important contributor to cardiovascular morbidity and mortality. Although the exact mechanisms behind AF are not completely elucidated, the underlying pathophysiological changes have been well described. Predisposal factors for AF include the older age, the increased left atrial size, the decreased left atrial function, the presence of heart failure and left ventricular systolic dysfunction and the presence of coronary heart disease or pulmonary or mitral valve disease. In addition to these factors, emerging evidence demonstrate that myocardial strain, fibrosis and inflammation, are associated with AF as well as the pathogenesis of the arrhythmia. The natruretic peptide system including Atrial Natriuretic Peptide (ANP), Brain Natriuretic Peptide (BNP) and C-type Natriuretic Peptide (CNP) is indicative of the level of myocardial strain which may predispose to AF. As a result, the aforementioned peptides are increased in AF patients. The levels of myocardial fibrosis biomarkers, such as ST2 and Galectin-3, are elevated suggesting atrial structural abnormalities, while the increased levels of CRP and Interleukin-6 supplement the inflammatory profile of AF patients. Emerging data for the aforementioned biomarkers are discussed in the present review.

Multiple biomarkers and arrhythmia outcome following catheter ablation of atrial fibrillation: The Guangzhou Atrial Fibrillation Project

BACKGROUND

Biomarkers have been related to the arrhythmia recurrence following catheter ablation (CA) of atrial fibrillation (AF). We hypothesized that concurrent measurement of several biomarkers would additively improve their predictive value.

METHODS

One thousand four hundred and ten consecutive AF patients (68% male; 57.2 ± 11.6 years) undergoing CA were enrolled. Baseline characteristics, serum B type brain natriuretic peptide (BNP) and high sensitivity C reactive protein (hsCRP), estimated glomerular filtration rate (eGFR), ablation parameters, arrhythmia data at discharge, 1, 3, 6, and then every 6 months post CA were collected. Follow-up ended when arrhythmia recurred or until 31st December 2016.

RESULTS

Three hundred and sixty-five (25.9%) patients had arrhythmia recurrence post-CA during a mean follow-up of 20.7 ± 8.8 months. BNP, hsCRP, and eGFR levels and their cut-off values of 237.45 pg/mL, 1.6 mg/dL, and 82.5 mL/min/1.73 m2 were good predictors for AF recurrence (all P < 0.01). On multivariate analysis, increasing BNP and hsCRP, decreasing eGFR, gender, and early recurrence (ER) were independent predictors of AF recurrence (all P < 0.01). Compared to BNP alone, BNP plus eGFR or both eGFR and CRP showed incrementally better predictive values (ROC comparisons, all P < 0.01). Similar findings were evident in the subgroups of patients with paroxysmal or nonparoxysmal AF.

CONCLUSION

Measurement of BNP, CRP, and eGFR were incrementally additive to clinical risk factors in a cumulative manner to improve prediction of arrhythmia recurrence post-CA of AF. The implications of poor arrhythmia outcome in AF patients with multiple abnormal biomarkers pre-CA procedure may help with patient selection and inform the likelihood of success or the need of more complicated CA procedure(s).

Apelin: A novel prognostic predictor for atrial fibrillation recurrence after pulmonary vein isolation

Apelin, the ligand for the APJ receptor, is involved in the pathogenesis of atrial fibrillation (AF). However, whether serum apelin can predict the recurrence of AF after pulmonary vein isolation (PVI) has not been determined.A prospective cohort study was performed in patients with AF (but without structural heart disease) who were undergoing first-time PVI. Serum apelin-12 was measured by enzyme-linked immunosorbent assay. Echocardiographic examination was performed at baseline, 3 months, and 6 months after PVI. Patients were followed up for 6 months after PVI, and the association between baseline apelin-12 and AF recurrence (early recurrence: within 3 months after ablation; late recurrence: 3-6 months after ablation) was analyzed.A total of 61 patients were included in the study. Baseline serum level of apelin-12 was significant lower in patients with early (median [interquartile range]: 1844 [1607-2061] vs 2197 [1895-2455] ng/L, P = .01) and late (1639 [1524-1853] vs 1923 [1741-2303] ng/L, P = .02) AF recurrence compared with patients without these events. Results of Cox stepwise multivariate analysis demonstrated that lower baseline apelin-12 (<2265 ng/L) was independently associated with increased AF recurrence within 6 months after PVI (P < .05). The specificity and positive predictive value of apelin-12 for AF recurrence were significantly higher than those of baseline N-terminal brain proBNP (60.4% vs 28.6%, P < .001; 58.8% vs 34.4%, P = .01), although the sensitivity and negative predictive value were similar.Reduced baseline serum apelin-12 may be an independent risk factor for the recurrence of AF after PVI in patients without structural heart disease.

Role of NT-proANP and NT-proBNP in patients with atrial fibrillation: Association with atrial fibrillation progression phenotypes

BACKGROUND

Electroanatomic remodeling in atrial fibrillation (AF) leads to disease initiation and perpetuation. Although atrial natriuretic peptide (ANP) is specifically expressed in the atria and is involved in atrial remodeling, B-type natriuretic peptide (BNP) is associated with mortality and cardiovascular events in AF.

OBJECTIVE

The purpose of this study was to investigate the association between N-terminal (NT)-proBNP and NT-proANP levels with 3 AF progression phenotypes: persistent AF, left atrial diameter (LAD) dilation, and left atrial low-voltage areas (LVAs).

METHODS

We studied NT-proBNP and NT-proANP in a discovery cohort (n = 51) and replicated the findings in a validation cohort (n = 241) undergoing first AF catheter ablation. Blood plasma samples from femoral vein were collected before catheter ablation. LVAs were determined using high-density maps and defined as <0.5 mV.

RESULTS

In our pilot cohort (age 62 ± 10 years; 63% male; 59% persistent AF; 22% LVA), NT-proANP-but not NT-proBNP-levels were significantly higher in LVA patients (14.1 vs 8.6 ng/mL; P = .009) and correlated with LAD (r² = 0.362; P = .011). These results were replicated in the validation cohort (age 64 ± 11 years; 59% male; 59% persistent AF; 27% LVA) (12.7 vs 8.8 ng/mL; P = .016) and correlated with LAD (r² = 0.180; P = .019). NT-proANP levels increased according to 4 disease progression groups: paroxysmal AF without LVA, persistent AF without LVA, paroxysmal AF with LVA, and persistent AF with LVA (mean 15, 20, 19, and 27 ng/mL, respectively; P = .004).

CONCLUSION

Natriuretic peptides show different sensitivity for phenotypes of AF progression. The clinical impact of NT-proANP in refining individualized therapy and disease prevention should be addressed in larger studies.

Association of pre-ablation level of potential blood markers with atrial fibrillation recurrence after catheter ablation: a meta-analysis

Aims

The meta-analysis was aimed to search for candidate blood markers whose pre-ablation level was associated with atrial fibrillation (AF) recurrence after radiofrequency catheter ablation (RFCA).

Methods and results

A systematic literature search of PubMed, EMBASE, Springer Link, Web of Science, Wiley-Cochrane library, and supplemented with Google scholar search engine was performed. Thirty-six studies covering 11 blood markers were qualified for this meta-analysis. Compared with the nonrecurrence group, the recurrence group had increased pre-ablation level of atrial natriuretic peptide (ANP), brain natriuretic peptide (BNP), N-terminal pro-brain natriuretic peptide (NT-pro-BNP), interleukin-6 (IL-6), C-reactive protein, low density lipoprotein (LDL), and tissue inhibitor of metal loproteinase-2 (TIMP-2) [standardized mean difference (95% confidence interval): 0.37 (0.13-0.61), 0.77 (0.40-1.14), 1.25 (0.64-1.87), 0.37 (0.21-0.52), 0.35 (0.10-0.60), 0.24 (0.07-0.42), 0.17 (0.00-0.34), respectively], while no statistical difference of pre-ablation level of white blood cell, total cholesterol, triglyceride, and transforming growth factor-β1 was found. Subgroup analysis demonstrated that ANP was associated with AF recurrence in participants who had no concomitant structural heart diseases (SHD); however, not in participants who had SHD, C-reactive protein was associated with AF recurrence in Asian studies, whereas not in European studies.

Conclusion

Increased pre-ablation level of ANP, BNP, NT-pro-BNP, IL-6, C-reactive protein, LDL, and TIMP-2 was associated with greater risk of AF recurrence after RFCA.

Significant Increase in C-Reactive Protein and Serum Amyloid A in the Early Hours of Paroxysmal Atrial Fibrillation

Background

A number of data have been accumulated on inflammation in persistent and permanent atrial fibrillation (AF). Our aim was to study the process in paroxysmal AF (PAF) by measuring plasma concentrations of high-sensitivity C-reactive protein (hs-CRP), serum amyloid A (SAA) and fibrinogen in dynamics.

Methods

The markers were investigated in 51 patients (26 males and 25 females; 59.84 ± 1.60 years) at hospital admission (baseline), 24 hours and 28 days after sinus rhythm restoration. Fifty-two controls (26 males and 26 females; 59.50 ± 1.46 years) were selected.

Results

At baseline, hs-CRP and SAA concentrations were higher in patients (8.12 ± 0.82 vs. 5.57 ± 0.21 mg/L, P = 0.003; 16.04 ± 0.93 vs. 5.12 ± 0.23 ng/mL, P < 0.001, respectively) and these changes persisted 24 hours after sinus rhythm restoration (8.16 ± 0.71 vs. 5.57 ± 0.21 mg/L, P < 0.001; 12.99 ± 0.75 vs. 5.12 ± 0.23 ng/mL, P < 0.001, respectively). On the 28th day, no significant difference was measured (5.42 ± 0.29 vs. 5.57 ± 0.21 mg/L, P = 0.68; 5.89 ± 0.38 vs. 5.12 ± 0.23 ng/mL, P = 0.08, respectively). At any measurement, fibrinogen levels did not differ between patients and controls (3.30 ± 0.17 vs. 3.22 ± 0.11 g/L, P = 0.70; 3.32 ± 0.11 vs. 3.22 ± 0.11 g/L, P = 0.52; 3.24 ± 0.13 vs. 3.22 ± 0.11 g/L, P = 0.90, respectively).

Conclusion

PAF is associated with dynamics in hs-CRP and SAA plasma levels. The results suggest that inflammation is closely related to the arrhythmia initiation.

Natriuretic Peptides as Predictors of Atrial Fibrillation Recurrences Following Electrical Cardioversion

Electrical cardioversion (ECV) can be effective in restoring sinus rhythm (SR) in the majority of patients with atrial fibrillation (AF). Several factors that predispose to AF recurrences, such as age, AF duration and left atrial size have been used to guide a decision for cardioversion, but increasing evidence suggests that they may be rather poor markers of left atrial structural remodeling that determines the long-term success of a rhythm control strategy. In this context, the use of easily obtainable biomarkers, such as the levels of atrial natriuretic peptide (ANP) and B-type natriuretic peptide (BNP), to predict AF recurrences may be preferable. Since ANP production is associated with the extent of functional atrial myocardium, and both ANP and BNP reflect atrial pressure and mechanical stretching, these peptides are good candidate biomarkers to assess predisposition to AF recurrences. In this review we focus on the pathophysiological mechanisms and the available clinical evidence regarding the prediction of AF recurrences following successful ECV from pre-procedural ANP and BNP levels.

Rhythm outcomes after catheter ablation of atrial fibrillation. Clinical implication of biomarkers

Atrial fibrillation (AF) occurs as the result of numerous complex physiological processes in the atria leading to AF promotion and maintenance. Improved diagnostic techniques have identified various biomarkers which may play an important role in the prediction of AF related outcomes (cardio- and cerebrovascular events, as well as mortality and rhythm outcomes). Biomarkers refer to 'biological markers' and biomarkers in blood, urine as well as imaging marker (eg, dimensions (left atrial diameter and volume), anatomical features (left appendage and pulmonary vein anatomy), and physiological pattern (LAA flow velocity)) may play important role(s) as clinically important indices in relation to outcomes after different therapeutic strategies. However, the main domain in the biomarker field has focused on blood-based biomarkers, which are widely used to predict therapeutic success regarding underlying pathophysiological mechanism, such as inflammation, fibrosis, endothelial damage. This review provides an update of the role of clinically relevant biomarkers in AF, with particular focus on AF rhythm outcomes.

N-Terminal Pro-Brain Natriuretic Peptide Shows Diagnostic Accuracy for Detecting Atrial Fibrillation in Cryptogenic Stroke Patients

Background

Diagnosing paroxysmal atrial fibrillation in patients with stroke can be difficult. We aimed to determine if N-terminal pro-brain natriuretic peptide can help identify paroxysmal atrial fibrillation in cryptogenic stroke.

Methods and results

Among 264 ischemic stroke patients, serum levels of N-terminal pro-brain natriuretic peptide were measured within 72 h of stroke onset. In cryptogenic stroke patients, 24-h Holter monitoring was used to look for paroxysmal atrial fibrillation within the first week and also three-and six-months after admission. First, patients with a defined etiology were used to construct a receiver operating characteristic curve for the diagnosis of atrial fibrillation. From this curve, the sensitivity and specificity of preestablished cutoff points for the diagnosis of atrial fibrillation were calculated. A logistic regression was performed to assess the independent relationship of the logarithm of N-terminal pro-brain natriuretic peptide levels with atrial fibrillation. The cutoff points were then evaluated in patients with cryptogenic stroke.

Results

One hundred eighty-four patients had a specific stroke etiology. Fifty-five patients had atrial fibrillation. Using multivariate analysis, the logarithm of N-terminal pro-brain natriuretic peptide levels was independently associated with atrial fibrillation. The area under the receiver operating characteristic curve of N-terminal pro-brain natriuretic peptide for the diagnosis of atrial fibrillation was 0·91 (95% confidence interval 0·87–0·95). The cutoff point of 265·5 pg/ml had a sensitivity of 100% and specificity of 70·5% for the diagnosis of atrial fibrillation. The cutoff point of 912 pg/ml had a sensitivity of 81·8% and a specificity of 87·5%. Eighty patients had a cryptogenic stroke. In 17, paroxysmal atrial fibrillation was found during follow-up. In these patients, the area under the curve for the diagnosis of paroxysmal atrial fibrillation was 0·83. The cutoff point of 265·5 had a sensitivity of 88·2% and a specificity of 61·9%. The cutoff point of 912 pg/ml had a sensitivity of 47·1% and a specificity of 88·9%.

Conclusion

N-terminal pro-brain natriuretic peptide has good accuracy in predicting the presence of paroxysmal atrial fibrillation in patients with cryptogenic stroke and can help to identify these patients.

Association between C-reactive protein and atrial fibrillation recurrence after catheter ablation: a meta-analysis

BACKGROUND

Atrial fibrillation (AF) is associated with inflammation. Increased serum C-reactive protein (CRP) levels are important representatives of an inflammatory state of AF. A variety of studies have evaluated whether increased CRP levels have an association with AF recurrence after catheter ablation. However, the results remain inconsistent, therefore, this meta-analysis was conducted to offer suggestions.

HYPOTHESIS

Increased baseline CRP have an association with AF recurrence after catheter ablation.

METHODS

Electronic databases including PubMed, Embase, Medline, ISI Web of Knowledge, and ScienceDirect were searched until December 31, 2012 for any CRP-associated studies. Overall and subgroup analyses were performed. Standardized mean difference (SMD) and 95% confidence interval (CI) were used to evaluate the associations between CRP levels and postablation AF recurrence. Statistical analysis was performed with Review Manager 5.2 and Stata 11.0.

RESULTS

Seven available studies were identified, which included 526 patients (179 recurrence vs 347 no recurrence). Overall, increased baseline CRP levels had significant positive association with postablation AF recurrence. The SMD in the CRP levels was 0.65 units (95% CI: 0.30-0.99), and the z-score for overall effect was 3.70 (P = 0.0002). The heterogeneity test showed that there were moderate differences between individual studies (P = 0.006, I(2) = 67%). Metaregression revealed that different sample sizes of studies possibly accounted for the heterogeneity. Positive associations were also found in subgroup analyses based on sample size. When stratifying for ethnicity, similarly significant associations were found in both European (Caucasian) and Asian populations.

CONCLUSIONS

Investigations demonstrate that baseline CRP levels are greater in patients with postablation AF recurrence. Further studies with larger sample size and delicate design for CRP should be conducted.