Plasma Asymmetric Dimethylarginine and Adverse Events in Patients with Atrial Fibrillation Referred for Coronary Angiogram

Objectives

Elevated plasma levels of asymmetric dimethylarginine (ADMA) have been reported to be associated with endothelial dysfunction, inflammation, and oxidative stress in multiple cardiovascular diseases. This study aimed to investigate whether ADMA was a predictor of clinical outcomes in atrial fibrillation (AF).

Methods and Results

From 2006-2009, 990 individuals were referred to our institution for coronary angiography. Among these patients, 141 subjects with a diagnosis of AF, including 52 paroxysmal AF (PAF) and 89 non-paroxysmal AF (non-PAF) patients, were identified as the study population. Plasma ADMA levels were measured. An adverse event was defined as the occurrence of ischemic stroke or cardiovascular death. The ADMA levels were higher in AF than non-AF patients (0.50±0.13 versus 0.45±0.07 µmol/L; p<0.001). Besides, non-PAF patients had higher ADMA levels than PAF patients (0.52±0.15 versus 0.48±0.08 µmol/L; p<0.001). During the follow-up of 30.7±14.4 months, 21 patients (14.9%) experienced adverse events, including cardiovascular death in 7 patients and ischemic stroke in 14. ADMA level, CHA₂DS₂-VASc score, and left atrial diameter were independent predictors of adverse events in the multivariate analysis. At a cutoff-value of 0.55 µmol/L, the Kaplan-Meier survival analysis showed that patients with a high ADMA level had a higher event rate during the follow-up period.

Conclusions

A higher level of ADMA was a risk factor of adverse events in AF patients, which was independent from the CHA₂DS₂-VASc score. It deserves to further study whether ADMA could potentially refine the clinical risk stratification in AF.     

房颤患者心房肌细胞的原代培养与应用

探索成功培养房颤(atrial fibrillation,AF)患者原代心房肌细胞的方法,能够为房颤发病机制的研究奠定实验基础。取心胸外科行迷宫手术患者的左心耳,利用I型胶原蛋白酶消化法培养房颤患者的原代心房肌细胞,通过免疫组化进行鉴定,同时对培养的心房肌细胞进行初步研究。与动物实验相反,房颤患者心房肌细胞缝隙连接蛋白40(connexin40,Cx40)及Kv1.5钾离子通道蛋白的表达量均降低。由此可见直接研究成人房颤患者的心房肌细胞具有更高的可靠性,同时也证明了房颤患者心房肌细胞的培养是研究其发病机制的基础。     

Left Atrial Appendage Morphology in Patients with Suspected Cardiogenic Stroke without Known Atrial Fibrillation

The left atrial appendage (LAA) is the typical origin for intracardiac thrombus formation. Whether LAA morphology is associated with increased stroke/TIA risk is controversial and, if it does, which morphological type most predisposes to thrombus formation. We assessed LAA morphology in stroke patients with cryptogenic or suspected cardiogenic etiology and in age- and gender-matched healthy controls. LAA morphology and volume were analyzed by cardiac computed tomography in 111 patients (74 males; mean age 60 ± 11 years) with acute ischemic stroke of cryptogenic or suspected cardiogenic etiology other than known atrial fibrillation (AF). A subgroup of 40 patients was compared to an age- and gender-matched control group of 40 healthy individuals (21 males in each; mean age 54 ± 9 years). LAA was classified into four morphology types (Cactus, ChickenWing, WindSock, CauliFlower) modified with a quantitative qualifier. The proportions of LAA morphology types in the main stroke group, matched stroke subgroup, and control group were as follows: Cactus (9.0%, 5.0%, 20.0%), ChickenWing (23.4%, 37.5%, 10.0%), WindSock (47.7%, 35.0%, 67.5%), and CauliFlower (19.8%, 22.5%, 2.5%). The distribution of morphology types differed significantly (P<0.001) between the matched stroke subgroup and control group. The proportion of single-lobed LAA was significantly higher (P<0.001) in the matched stroke subgroup (55%) than the control group (6%). LAA volumes were significantly larger (P<0.001) in both stroke study groups compared to controls patients. To conclude, LAA morphology differed significantly between stroke patients and controls, and single-lobed LAAs were overrepresented and LAA volume was larger in patients with acute ischemic stroke of cryptogenic or suspected cardiogenic etiology.     

Galectin-3 in Patients with Atrial Fibrillation Undergoing Radiofrequency Catheter Ablation

Background

Galectin-3 (Gal-3) is an emerging biomarker in heart failure that is involved in fibrosis and inflammation. However, its potential value as a prognostic marker in atrial fibrillation (AF) is unknown. The aim of this study was to assess the impact of AF catheter ablation on Gal-3 and evaluate its prognostic impact for predicting rhythm outcome after catheter ablation.

Methods

Gal-3 was measured at baseline and after 6 months using specific ELISA. AF recurrences were defined as any atrial arrhythmia lasting longer than 30 sec within 6 months after ablation.

Results

In 105 AF patients (65% males, age 62±9 years, 52% paroxysmal AF) undergoing catheter ablation, Gal-3 was measured at baseline and after 6 months and compared with an AF-free control cohort (n=14, 50 % males, age 58±11 years). Gal-3 was higher in AF patients compared with AF-free controls (7.8±2.9 vs. 5.8±1.8, ng/mL, p=0.013). However, on multivariable analysis, BMI (p=0.007) but not AF (p=0.068) was associated with Gal-3. In the AF cohort, on univariable analysis higher Gal-3 levels were associated with female gender (p=0.028), higher BMI (p=0.005) and both CHADS2 (p=0.008) and CHA2DS2-VASC (p=0.016) scores, however, on multivariable analysis only BMI remained significantly associated with baseline Gal-3 (p=0.016). Gal-3 was similar 6 months after AF catheter ablation and was not associated with sinus rhythm maintenance.

Conclusions

Although galectin-3 levels are higher in AF patients, this is driven by cardiometabolic co-morbidities and not heart rhythm. Gal-3 is not useful for predicting rhythm outcome of catheter ablation.     

心房颤动并发血栓栓塞患者脑钠肽与D-二聚体的表达及相关性分析

目的:观察房颤及房颤并发血栓栓塞患者血浆内脑钠肽(brain natriuretic peptide,BNP)和D-二聚体(D-dimer)的表达水平;探讨两者表达水平的关联性以及两者对房颤血栓栓塞的预测价值。方法:回顾分析2010年5月-2012年12月上海市第一人民医院心内科住院病人;根据入组及排除标准将符合条件的研究对象74例分为对照组、单纯房颤组与房颤血栓组;对所有对象进行数据采集,包括年龄、性别、血脂情况、高血压病史、血糖等情况;对所有对象进行D-dimer及BNP水平的数据采集。结果:(1)房颤血栓组的年龄明显高于对照组(P0.01)和单纯房颤组(P0.001);(2)房颤血栓组的D-dimer和BNP水平高于单纯房颤组(P0.05)和对照组(P0.001);(3)单纯房颤组BNP水平与D-dimer水平呈正相关性(r=0.507,P=0.004),房颤血栓组BNP水平与D-dimer水平呈正相关性(r=0.680,P0.001)。结论:(1)心房颤动患者随着年龄的增加并发血栓栓塞风险也增加,指导我们在临床治疗时需要重视年龄因素。(2)患者血浆中D-dimer和BNP水平的增高是心房颤动并发血栓栓塞患者的危险信号。(3)D-dimer和BNP检测在预防心房颤动并发血栓栓塞中有重要的临床意义。     

Plasma Concentrations of Digoxin after Oral Administration in the Fasting and Postprandial State

After the oral administration of 0·5 mg of digoxin in tablet form to fasting subjects peak plasma levels were reached in 30 to 60 minutes. Levels then fell to reach a plateau at six to eight hours. When the same dose was given after food the peak plasma concentrations were significantly lower, but the concentrations reached in samples obtained from two to eight hours after the dose did not differ appreciably from corresponding samples obtained in the fasting experiments.In a four-week cross-over study of 21 patients on maintenance therapy, digoxin taken regularly in the fasting state produced plasma concentrations similar to those obtained when the drug was taken after meals.The rapid appearance of digoxin in the blood suggests that the oral route of administration is adequate for most patients who require rapid digitalization, and the timing of maintenance dosage in relation to meals is unimportant.     

Myocardial and Skeletal Muscle Concentrations of Digoxin in Patients on Long-term Therapy

The digoxin content was measured in samples of left ventricular papillary muscle, skeletal muscle, and plasma obtained during mitral valve replacement from eight patients on maintenance treatment with the drug. The content in papillary muscle ranged from 15·5 to 132 ng/g (mean 77·7) and in skeletal muscle from 7·5 to 23 ng/g (mean 11·3). The ratio of myocardial digoxin concentration to plasma concentration varied between patients from 39:1 to 155:1. No simple relationship exists between plasma levels of digoxin and its concentration in the heart muscle, but total myocardial concentration may not accurately reflect therapeutic activity.     

Beta1-Adrenoceptor Polymorphism Predicts Flecainide Action in Patients with Atrial Fibrillation

Background

Antiarrhythmic action of flecainide is based on sodium channel blockade. Beta₁-adrenoceptor (β₁AR) activation induces sodium channel inhibition, too. The aim of the present study was to evaluate the impact of different β₁AR genotypes on antiarrhythmic action of flecainide in patients with structural heart disease and atrial fibrillation.

Methodology/Principal Findings

In 145 subjects, 87 with atrial fibrillation, genotyping was performed to identify the individual β₁AR Arg389Gly and Ser49Gly polymorphism. Resting heart rate during atrial fibrillation and success of flecainide-induced cardioversion were correlated with β₁AR genotype. The overall cardioversion rate with flecainide was 39%. The Arg389Arg genotype was associated with the highest cardioversion rate (55.5%; OR 3.30; 95% CI; 1.34–8.13; p = 0.003) compared to patients with Arg389Gly (29.5%; OR 0.44; 95% CI; 0.18–1.06; p = 0.066) and Gly389Gly (14%; OR 0.24; 95% CI 0.03–2.07; p = 0.17) variants. The single Ser49Gly polymorphism did not influence the conversion rate. In combination, patients with Arg389Gly-Ser49Gly genotype displayed the lowest conversion rate with 20.8% (OR 0.31; 95% CI; 0.10–0.93; p = 0.03). In patients with Arg389Arg variants the heart rate during atrial fibrillation was significantly higher (110±2.7 bpm; p = 0.03 vs. other variants) compared to Arg389Gly (104.8±2.4 bpm) and Gly389Gly (96.9±5.8 bpm) carriers. The Arg389Gly-Ser49Gly genotype was more common in patients with atrial fibrillation compared to patients without atrial fibrillation (27.6% vs. 5.2%; HR 6.98; 95% CI; 1.99–24.46; p<0.001).

Conclusions

The β₁AR Arg389Arg genotype is associated with increased flecainide potency and higher heart rate during atrial fibrillation. The Arg389Gly-Ser49Gly genotype might be of predictive value for atrial fibrillation.     

胺碘酮联合厄贝沙坦治疗阵发性心房颤动的疗效观察

目的:探讨胺碘酮与厄贝沙坦联合治疗阵发性心房颤动的临床疗效。方法:将我院收治的97例阵发性心房颤动患者,随机分为观察组(N=49)和对照组(N=48)。对照组单纯服用胺碘酮,治疗组在此基础上加用厄贝沙坦。治疗随访12个月,一级观测终点为房颤复发。结果:治疗后12个月,观察组左心房内径显著小于对照组(P>0.05);治疗后6、12个月,观察组窦性维持率分别为89.8%、81.6%,对照组分别为72.9%、62.5%,两组均有统计学差异(P<0.05);治疗期间,观察组房颤复发率24.5%,显著低于对照组47.9%(P<0.05)。结论:胺碘酮联合厄贝沙坦治疗阵发性心房颤动于窦性心律的维持优于单用胺碘酮,且减少房颤复发,抑制左心房扩大。     

Risk of Ischemic Stroke after Intracranial Hemorrhage in Patients with Atrial Fibrillation

Background

We aimed to estimate the risk of ischemic stroke after intracranial hemorrhage in patients with atrial fibrillation.

Materials and Methods

Using discharge data from all nonfederal acute care hospitals and emergency departments in California, Florida, and New York from 2005 to 2012, we identified patients at the time of a first-recorded encounter with a diagnosis of atrial fibrillation. Ischemic stroke and intracranial hemorrhage were identified using validated diagnosis codes. Kaplan-Meier survival statistics and Cox proportional hazard analyses were used to evaluate cumulative rates of ischemic stroke and the relationship between incident intracranial hemorrhage and subsequent stroke.

Results

Among 2,084,735 patients with atrial fibrillation, 50,468 (2.4%) developed intracranial hemorrhage and 89,594 (4.3%) developed ischemic stroke during a mean follow-up period of 3.2 years. The 1-year cumulative rate of stroke was 8.1% (95% CI, 7.5–8.7%) after intracerebral hemorrhage, 3.9% (95% CI, 3.5–4.3%) after subdural hemorrhage, and 2.0% (95% CI, 2.0–2.1%) in those without intracranial hemorrhage. After adjustment for the CHA₂DS₂-VASc score, stroke risk was elevated after both intracerebral hemorrhage (hazard ratio [HR], 2.8; 95% CI, 2.6–2.9) and subdural hemorrhage (HR, 1.6; 95% CI, 1.5–1.7). Cumulative 1-year rates of stroke ranged from 0.9% in those with subdural hemorrhage and a CHA₂DS₂-VASc score of 0, to 33.3% in those with intracerebral hemorrhage and a CHA₂DS₂-VASc score of 9.

Conclusions

In a large, heterogeneous cohort, patients with atrial fibrillation faced a substantially heightened risk of ischemic stroke after intracranial hemorrhage. The risk was most marked in those with intracerebral hemorrhage and high CHA₂DS₂-VASc scores.     

Effect of Propranolol on Exercise Tolerance of Patients with Atrial Fibrillation

Six patients with atrial fibrillation who were taking digitalis were exercised before and after 30 mg. of propranolol twice daily. Though there was a lower pulse rate at rest and on exercise in all patients, three suffered deterioration of exercise tolerance. It is concluded that propranolol does not improve the exercise tolerance of patients with atrial fibrillation whose resting ventricular rate is controlled with digitalis.     

胺碘酮对急诊老年快速心房颤动患者的疗效观察

目的:通过与传统控制心室率的药物去乙酰毛花苷注射液进行对比,探讨胺碘酮注射液对老年快速型心房颤动患者的临床疗效.方法:选择2010年5月～2012年6月我院急诊科收治的老年快速房颤患者60例,按就诊先后顺序随机分为对照组与胺碘酮治疗组,每组30例.胺碘酮治疗组患者先给予胺碘酮注射液150 mg以生理盐水稀释后缓慢静脉注射,继以0.5 mg/min静滴;对照组患者先予去乙酰毛花苷注射液0.2 mg稀释后缓慢静脉推注,若20 min无效则再次给药,两组患者的院内观察周期均为24h,患者在观察过程中行全程心电监护,观察不同时间段(用药后0、0.5、2、12、24 h)患者的心室率,血压的变化;比较两种治疗方法的临床疗效及对患者复律情况的影响.结果:治疗前,两组患者的心室率比较无显著性差异(P＞0.05);第一次用药后0.5h,两组患者的心室率都较治疗前显著下降(P＜0.01),且用乙酰毛花苷注射液治疗的对照组显著低于胺碘酮治疗组(P＜0.05);用药后2和12h,两组患者的心室率比较均无显著性差异(P＞0.05);用药后24h,胺碘酮治疗组患者的心室率较对照组显著降低(P＜0.01).对照组的临床有效率为40.0％,复律率为l6.7％;而胺碘酮治疗组的临床有效率为73.3％,复律率为43.3％,分别显著高于对照组(P＜0.01).与用药前比较,用药后0.5、2、12和24h患者的收缩压略有下降,但差异均无统计学意义(P＞0.05).结论:与去乙酰毛花苷注射液比较,胺碘酮注射液可更有效地降低老年患者24h心室率,复律率和有效率更高,但在应用过程中需注意其不良反应.     

Protein Analysis of Atrial Fibrosis via Label-Free Proteomics in Chronic Atrial Fibrillation Patients with Mitral Valve Disease

Background

Atrial fibrosis, as a hallmark of atrial structure remodeling, plays an important role in maintenance of chronic atrial fibrillation, but interrelationship of atrial fibrosis and atrial fibrillation is uncertain. Label-free proteomics can implement high throughput screening for finding and analyzing pivotal proteins related to the disease.. Therefore, we used label-free proteomics to explore and analyze differentially proteins in chronic atrial fibrillation patients with mitral valve disease.

Methods

Left and right atrial appendages obtained from patients with mitral valve disease were both in chronic atrial fibrillation (CAF, AF≥6 months, n = 6) and in sinus rhythm (SR, n = 6). One part of the sample was used for histological analysis and fibrosis quantification; other part were analyzed by label-free proteomic combining liquid chromatography with mass spectrometry (LC-MS), we utilized bioinformatics analysis to identify differential proteins.

Results

Degree of atrial fibrosis was higher in CAF patients than that of SR patients. 223 differential proteins were detected between two groups. These proteins mainly had vital functions such as cell proliferation, stress response, focal adhesion apoptosis. We evaluated that serine/threonine protein kinase N2 (PKN2), dermatopontin(DP), S100 calcium binding protein B(S100B), protein tyrosine kinase 2(PTK2) and discoidin domain receptor tyrosine kinase 2(DDR2) played important roles in fibrotic process related to atrial fibrillation.

Conclusion

The study presented differential proteins responsible for atrial fibrosis in chronic atrial fibrillation patients through label-free proteomic analysis. We assessed some vital proteins including their characters and roles. These findings may open up new realm for mechanism research of atrial fibrillation.     

Polymorphisms of Renin-Angiotensin-Aldosterone System Gene in Chinese Han Patients with Nonfamilial Atrial Fibrillation

BackgroundAtrial fibrillation(AF) is the most common arrhythmia in the adult population. The activated renin-angiotensin-aldosterone system (RAS) has been reported to play an important role in the pathogenesis of atrial fibrillation. The aim of this study was to investigate the association between nonfamilial AF and polymorphisms in RAS gene.MethodsA total of 931 patients with nonfamilial AF, 663 non-AF heart disease patients and 727 healthy subjects were selected. 10 tagSNPs (tSNPs) (ACE gene rs8066114, AGT gene rs7539020, rs3789678, rs2478544, rs11568023, rs2478523, rs4762, rs699 and CYP11B2 rs3802230, rs3097) were chosen and genotyped in our study. Single-locus analysis and haplotype analysis were used in this study.ResultsIn single-locus analysis, we found rs11568023 and rs3789678 in AGT gene were associated with nonfamilial AF in Chinese Han population. AF risk was associated with rs3789678 between the AF group and control groups. Under dominant model, the significant AF risk was observed in rs3789678 between the AF group and non AF heart control group; And the protective effect was found in rs11568023, compared with the non-AF heart disease control group. In multilocus haplotype analysis, the association between frequencies of the haplotypes and AF risk was showed in AGT gene (rs7539020-rs3789678), compared ‘TT’ haplotype with the common ‘TC’ haplotype, adjusted for age, gender, LVEF, LVEDD, LAD and frequency of hypertension and diabetes. The diplotype with ‘TC’, carrying rs3789678-C-allele, was associated with reduced risk of AF between the AF group and the healthy control group. The diplotype with ‘TT’ haplotype in the same block, carrying rs3789678-T-allele, was associated with increased risk of AF.ConclusionsVia a large-scale case-control study, we found that rs3789678 site was potential susceptible locus of AF whereas rs11568023 was protective factor.     

The Prevalence and Incidence of Atrial Fibrillation in Patients with Acute Pulmonary Embolism

Background

Symptomatic pulmonary embolism (PE) is a major cause of cardiovascular death and morbidity. Estimated prevalence and incidence of atrial fibrillation (AF) in developed countries are between 388–661 per 100,000, and 90–123 per 100,000 person-years respectively. However, the prevalence and incidence of AF in patients presenting with an acute PE and its predictors are not clear.

Methods

Individual patient clinical details were retrieved from a database containing all confirmed acute PE presentations to a tertiary institution from 2001–2012. Prevalence and incidence of AF was tracked from a population registry by systematically searching for AF during any hospital admission (2000–2013) based on International Classification of Disease (ICD-10) code.

Results

Of the 1,142 patients included in this study, 935 (81.9%) had no AF during index PE admission whilst 207 patients had documented baseline AF (prevalence rate 18,126 per 100,000; age-adjusted 4,672 per 100,000). Of the 935 patients without AF, 126 developed AF post-PE (incidence rate 2,778 per 100,000 person-years; age-adjusted 984 per 100,000 person-years). Mean time from PE to subsequent AF was 3.4 ± 2.9 years. Total mortality (mean follow-up 5.0 ± 3.7 years) was 42% (n = 478): 35% (n = 283), 59% (n = 119) and 60% (n = 76) in the no AF, baseline AF and subsequent AF cohorts respectively. Independent predictors for subsequent AF after acute PE include age (hazard ratio [HR] 1.06, 95% confidence interval [CI] 1.04–1.08, p<0.001), history of congestive cardiac failure (HR 1.88, 95% CI 1.12–3.16, p = 0.02), diabetes (HR 1.72, 95% CI 1.07–2.77, p = 0.02), obstructive sleep apnea (HR 4.83, 1.48–15.8, p = 0.009) and day-1 serum sodium level during index PE admission (HR 0.94, 95% CI 0.90–0.98, p = 0.002).

Conclusions

Patients presenting with acute PE have a markedly increased age-adjusted prevalence and subsequent incidence of AF. Screening for AF may be of importance post-PE.     

Late Sodium Current in Human Atrial Cardiomyocytes from Patients in Sinus Rhythm and Atrial Fibrillation

Slowly inactivating Na⁺ channels conducting “late” Na⁺ current (I_Na,late) contribute to ventricular arrhythmogenesis under pathological conditions. I_Na,late was also reported to play a role in chronic atrial fibrillation (AF). The objective of this study was to investigate I_Na,late in human right atrial cardiomyocytes as a putative drug target for treatment of AF. To activate Na⁺ channels, cardiomyocytes from transgenic mice which exhibit I_Na,late (ΔKPQ), and right atrial cardiomyocytes from patients in sinus rhythm (SR) and AF were voltage clamped at room temperature by 250-ms long test pulses to -30 mV from a holding potential of -80 mV with a 100-ms pre-pulse to -110 mV (protocol I). I_Na,late at -30 mV was not discernible as deviation from the extrapolated straight line IV-curve between -110 mV and -80 mV in human atrial cells. Therefore, tetrodotoxin (TTX, 10 μM) was used to define persistent inward current after 250 ms at -30 mV as I_Na,late. TTX-sensitive current was 0.27±0.06 pA/pF in ventricular cardiomyocytes from ΔKPQ mice, and amounted to 0.04±0.01 pA/pF and 0.09±0.02 pA/pF in SR and AF human atrial cardiomyocytes, respectively. With protocol II (holding potential -120 mV, pre-pulse to -80 mV) TTX-sensitive I_Na,late was always larger than with protocol I. Ranolazine (30 μM) reduced I_Na,late by 0.02±0.02 pA/pF in SR and 0.09±0.02 pA/pF in AF cells. At physiological temperature (37°C), however, I_Na,late became insignificant. Plateau phase and upstroke velocity of action potentials (APs) recorded with sharp microelectrodes in intact human trabeculae were more sensitive to ranolazine in AF than in SR preparations. Sodium channel subunits expression measured with qPCR was high for SCN5A with no difference between SR and AF. Expression of SCN8A and SCN10A was low in general, and lower in AF than in SR. In conclusion, We confirm for the first time a TTX-sensitive current (I_Na,late) in right atrial cardiomyocytes from SR and AF patients at room temperature, but not at physiological temperature. While our study provides evidence for the presence of INa,late in human atria, the potential of such current as a target for the treatment of AF remains to be demonstrated.     

Plasma Digoxin Concentration in Children with Heart Failure

A dosage schedule for digoxin medication is presented which has proved effective and safe in children of different ages with heart failure due to a variety of cardiac conditions. The plasma digoxin concentrations during maintenance therapy, using this schedule, agree closely with previously reported therapeutic adult plasma concentrations, though the results do not exclude the efficiency and safety of higher doses. A twice-daily dosage regimen is suggested.     

Plasma Haptoglobin Concentrations Are Elevated in Patients with Coronary Artery Disease

Inflammation underlies the development and progression of coronary artery plaques. Haptoglobin (Hp) is an acute phase protein, the synthesis of which is increased during inflammation. The aim of this study was to investigate plasma Hp concentrations and phenotype in patients with coronary artery disease (CAD). We recruited 359 patients with fixed luminal stenosis ≥50% in at least one coronary artery (CAD group) and 83 patients with luminal stenosis ≤40%, normal ejection fraction, and normal regional wall motion (control group). Plasma Hp concentrations were measured using a phenotype-specific enzyme-linked immunosorbent assay. Hp phenotype was determined by native polyacrylamide gel electrophoresis. Plasma lipid concentrations were measured. Plasma Hp concentrations were significantly higher in the CAD compared with the control group (262.4±144.2 vs 176.0±86.7 ng/mL, P<0.001); however, there was no between group difference in the distribution of Hp phenotype (1-1 = 7.5% vs 7.2%; 2-1 = 40.4% vs 42.2%; 2-2 = 52.1% vs 50.6%). Stepwise multivariate logistic regression revealed that high Hp concentrations (odds ratio [OR] = 5.865), male sex (OR = 3.689), hypertension (OR = 2.632), diabetes mellitus (OR = 3.300), and low-density lipoprotein concentrations (OR = 1.480) were independently associated with CAD (all P<0.05). Hp phenotype was not associated with CAD. Plasma Hp concentrations were significantly correlated with the severity of luminal stenosis (r = 0.236, P<0.001). Our findings suggest that plasma Hp concentrations may be elevated in patients with CAD. There does not appear to be any relationship between Hp phenotype and CAD.     

Impact of Body Mass Index on Plasma N-Terminal ProB-Type Natriuretic Peptides in Chinese Atrial Fibrillation Patients without Heart Failure

Background

An inverse relationship between body mass index (BMI) and circulating levels of N-terminal proB-type natriuretic peptide (NT-proBNP) has been demonstrated in subjects with and without heart failure. Obesity also has been linked with increased incidence of atrial fibrillation (AF), but its influence on NT-proBNP concentrations in AF patients remains unclear. This study aimed to investigate the effect of BMI on NT-proBNP levels in AF patients without heart failure.

Methods

A total of 239 consecutive patients with AF undergoing catheter ablation were evaluated. Levels of NT-proBNP and clinical characteristics were compared in overweight or obese (BMI≥25 kg/m²) and normal weight (BMI<25 kg/m²) patients.

Results

Of 239 patients, 129 (54%) were overweight or obese. Overweight or obese patients were younger, more likely to have a history of nonparoxysmal AF, hypertension, and diabetes mellitus. Levels of NT-proBNP were significantly lower in overweight or obese than in normal weight subjects (P<0.05). The relationship of obesity and decreased NT-proBNP levels persisted in subgroup of hypertension, both gender and both age levels (≥65 yrs and <65 yrs).Multivariate linear regression identified BMI as an independent negative correlate of LogNT-proBNP level.

Conclusions

An inverse relationship between BMI and plasma NT-proBNP concentrations have been demonstrated in AF patients without heart failure. Overweight or obese patients with AF appear to have lower NT-proBNP levels than normal weight patients.