Assessment of interleukin-1 gene cluster polymorphisms in lone atrial fibrillation: new insight into the role of inflammation in atrial fibrillation

BACKGROUND

Systemic inflammation is accepted as one of the pathophysiological mechanisms of atrial fibrillation (AF). The role of inflammation has been shown previously. Interleukin (IL) system is the main modulator of the inflammatory responses and genetic polymorphisms of IL-1 cluster genes are associated with increased risk for inflammatory diseases.

OBJECTIVES

To investigate the association between polymorphisms of IL-1 cluster genes and lone AF.

SUBJECTS AND METHODS

DNA samples were collected from 70 proven lone AF patients and 70 healthy subjects. Genomic DNA was typed for the variable number of the tandem repeat (VNTR) IL-1 receptor antagonist (RN) gene polymorphism, IL-1B -511 C > T(rs16944) promoter polymorphism, and +3953 C > T(rs1143634) polymorphism in exon 5 by polymerase chain reaction.

RESULTS

In lone AF group the frequency of IL-1RN2/2 and IL-1RN1/2 genotypes were higher than in the control group (7.2% vs 4.3% and 48.5% vs 22.8%, respectively; χ(2) = 14.1; P = 0.028). The frequency of allele 2 was significantly higher in the lone AF group (32.1% vs 15.7%; χ(2) = 10.7; P = 0.005). Allele and genotype distribution of IL-1B -511 C > T and +3953 C > T polymorphisms were not statistically different between the groups. C-reactive protein (CRP) levels were higher in lone AF patients compared to the control group (median = 1.25, interquartile range [IQR] = 0.85 vs median = 1.08, IQR 0.46 mg/L, respectively; P = 0.02). In multivariate regression analysis, presence of allele 2 of IL-1 VNTR polymorphism and elevated plasma high-sensitive-CRP levels were the independent predictors of lone AF.

CONCLUSION

Presence of allele 2 of VNTR polymorphism of IL-1RN gene may cause increased risk for lone AF probably due to the inadequate limitation of inflammatory reactions.

Significance of intraoperative testing in right-sided implantable cardioverter-defibrillators

Background

Implantation of implantable cardioverter-defibrillators (ICD) from the left pectoral region is the standard therapeutical method. Increasing numbers of system revisions due to lead dysfunction and infections will consecutively increase the numbers of right-sided implantations. The reliability of devices implanted on the right pectoral side remains controversially discussed, and the question of testing these devices remains unanswered.

Methods

In a prospectively designed study all 870 patients (60.0±14 years, 689 male) who were treated with a first ICD from July 2005 until May 2012 and tested intraoperatively according to the testing protocol were analyzed. The indication for implantation was primary prophylactic in 71.5%. Underlying diseases included ischemic cardiomyopathy (50%), dilative cardiomyopathy (37%), and others (13%). Mean ejection faction was 27±12%. Implantation site was right in 4.5% and left in 95.5%.

Results

Five patients supplied with right-sided ICD (13%, p = 0.02 as compared to left-sided) failed initial intraoperative testing with 21 J. 3 patients were male. The age of the patients failing intraoperative testing with right-sided devices appeared higher than of patients with left-sided devices (p = 0.07). The ejection fraction was 28±8%. All patients reached a sufficient DFT ≤ 21 J after corrective procedures.

Conclusion

Implantation of ICDs on the right side results in significantly higher failure rate of successful termination of intraoperatively induced ventricular fibrillation. The data of our study suggest the necessity of intraoperative ICD testing in right-sided implanted ICDs.

Analysis of circadian variation of acute myocardial infarction: afternoon predominance in Turkish population

BACKGROUND

Although data about circadian variation of myocardial infarction (MI) in western populations reveal morning peak between 06:00 and 12:00 hours, differences have been reported in different regions of the world and ethnic groups. We aimed to evaluate circadian variation of MI in a Turkish cohort.

METHODS

A total of 476 patients (mean age 56.7 +/- 11.7; 80% men) with acute st elevation MI were included into the study. Patients were categorised into four 6-h increments (00:01-06:00; 06:01-12:00; 12:01-18:00 and 18:01-24:00 hours).

RESULTS

Onset of MI exhibited significant circadian variation among four time periods (p < 0.001), demonstrating afternoon peak (between 12:01 and 18:00 hours) and trough between 00:01 and 06:00 hours. Incidence of MI between 12:01 and 18:00 hours was significantly higher when compared with other three 6-h periods (p = 0.001). Incidence of MI between 00:01 and 06:00 hours was significantly lower when compared with other three 6-h periods (p = 0.001). Incidence of MI between 12:01 and 18:00 hours was 1.64 times that of average frequency of the remaining 18:00 hours of the day and 2.3 times that of frequency between 00:01 and 06:00 hours. When analysed for the subgroups of the study sample, only smoking blunted the afternoon peak.

CONCLUSIONS

Instead of early morning peak in western countries, there is afternoon predominance in circadian variation of MI in a Turkish cohort. It may be related with genetic and/or demographic characteristics of Turkish population. Further studies are required to determine underlying pathophysiological mechanisms causing these differences in chronobiology of MI among populations.

Uncommon presentation of postcardiac injury syndrome: Acute pericarditis after percutaneous coronary intervention

Postcardiac injury syndrome (PCIS) is a common complication after cardiac surgery and myocardial infarction which is defined as a late developing pleuropericarditis accompanied by a friction rub, elevated inflammation markers and pericardial or pleural effusion. Although almost all of the cases follow a major cardiac operation or myocardial infarction, and are called as postpericardiotomy syndrome (PPS) and postmyocardial infarction syndrome (PMIS), unusual presentations after minor cardiac insults, have also been reported in the literature. We have described an unusual case of PCIS with typical clinical, laboratory, echocardiographic findings that occurred after a prolonged and complicated stent implantation procedure.

High sensitivity CRP levels predict atrial tachyarrhythmias in rheumatic mitral stenosis

BACKGROUND

The different levels of inflammation in rheumatic mitral stenosis determine its clinical consequences. Atrial fibrillation is frequently encountered in mitral stenosis, though the independent role of chronic inflammation in determining atrial tachyarrhythmia occurrence in rheumatic heart disease has not been demonstrated previously.

METHODS

Measurements of C-reactive protein (CRP) with a high sensitivity assay to detect chronic inflammation were performed in a homogenous group of 50 patients with rheumatic mitral stenosis, who were in sinus rhythm. Patients were questioned to exclude confounders of CRP elevation. The patients underwent a twenty-four-hour ambulatory ECG monitoring to check for asymptomatic atrial tachyarrhythmias and were in addition classified according to the presence of atrial tachyarrhythmias.

RESULTS

Forty-four percent of patients showed a total of 100 episodes of atrial tachyarrhythmias where 63% of these episodes were paroxysmal atrial fibrillation. The CRP values in patients with tachyarrhythmias were significantly higher than in patients who remained in sinus rhythm (4.2 +/- 0.55 mg/L vs 1.99 +/- 0.36 mg/L, P < 0.001). A logistic regression analysis revealed only CRP levels and previous history of mitral valvuloplasty significantly determined tachyarrhythmia occurrence where age, left atrial volumes, mitral gradients had no statistically significant effect.

CONCLUSIONS

Our data implicated that nearly half of the mitral stenosis patients who are in sinus rhythm develop asymptomatic tachyarrhythmias and the higher levels of CRP in these patients show the significant effect of persistent inflammation on arrhythmia occurrence.

[Magnetic navigation in invasive electrophysiological diagnostic and therapy]

Electrophysiological stimulation and ablation is currently performed with manually deflectable catheters of different lengths and curves. Disadvantages of conventional therapy are catheter stiffness, limited local stability, risk of dislocation or perforation, and reduced tissue contact in regions with difficult access. Fluoroscopy to control catheter movement and position may require substantial radiation times. Magnetic navigation was first applied for right heart catherization in congenital heart disease in 1991; the first electrophysiological application took place in 2003. Today, an ablation electrode with small magnets is aligned in the patient's heart by two external magnets positioned at both sides of the thorax. Antegrade and retrograde movement of the distal catheter tip are performed via an external device on the patient's thigh. Three-dimensional MRI scans acquired before intervention can be merged with electroanatomical reconstruction, leading to further reductions of radiation burden. During treatment of supraventricular tachyarrhythmias high local precision of magnetically guided catheters, good local stability, and a substantially reduced radiation time have been reported. First applications in ventricular tachyarrhythmias and complex congenital cardiac defects indicate a comparable effect. Limitations of this therapy are the application in left atrial procedures (open irrigated ablation catheters not yet available), difficult transaortic retrograde approach (high lead flexibility), and the considerable costs. Magnet-assisted navigation is feasible during percutaneous coronary interventions of tortuous coronary arteries and in positioning guidewires in coronary sinus side branches for resynchronisation therapy. Future applications will be complex left atrial procedures, magnetically guided cardiac stem cell therapy, local drug application, and extracardiac vessel therapy.

[Use of the NavX navigation system in ablation of atrial fibrillation]

Catheter ablation, notably the electric isolation of pulmonary veins, has become a well-established therapeutic approach in symptomatic atrial fibrillation. The NavX navigation system has been described to facilitate pulmonary vein isolation in patients with AF. EnSite NavX (Endocardial Solutions, St. Jude Medical, Inc., St. Paul, MN, USA) is a novel navigation system that measures the local voltage on every standard intra-cardiac electrode and calculates the electrode position in three-dimensional (3D) space. Any individual electrode of each catheter in 3D-space can be displayed and labelled individually. The geometry of any cardiac chamber can be reconstructed and additional information, e.g. electrical activation spreading, can be displayed colour coded on the surface. Recent studies investigating the possible advantages of this system in the ablation of persistent or paroxysmal atrial fibrillation are summarized. All reports showed a significant reduction in fluoroscopy and procedure time by the use of the NavX system compared to conventional fluoroscopic catheter guidance. This benefit can be obtained with simple visualisation of all intracardiac catheters alone or with additional reconstruction of the left atrium and pulmonary veins.

Noncardiogenic pulmonary edema associated with clopidogrel: a serious but unexpected side effect of clopidogrel

Clopidogrel has a favourable side effect profile, in which the most serious complications are related to bleeding diathesis. Drug reactions represent frequently encountered clinical problems that can also be life-threatening. In the present case, serious noncardiogenic pulmonary edema was observed as an idiosyncratic reaction after clopidogrel use. Using the Naranjo adverse drug reactions probability scale, a possible likelihood of this putative interaction between clopidogrel and pulmonary edema was calculated. Such an adverse effect of clopidogrel has never been reported before. The present report shows the importance of recognizing rare adverse reactions of newer drugs, such as clopidogrel, in clinical practice.

Uncommon presentation of Behçet's syndrome: aortic aneurysm and dissection due to Behçet's syndrome

Aneurysm and dissections localized to the ascending aorta are usually encountered in patients with atherosclerosis and hypertension. Behçet's syndrome is a rare vasculitic syndrome occasionally responsible for inflammation in small to large vessels. Aneurysm formation and dissection in the ascending aorta due to Behcet's disease is an even rarer presentation of this vasculitis that will be discussed in conjunction with a case presentation.

Impact of early tirofiban administration on myocardial salvage in patients with acute myocardial infarction undergoing infarct-related artery stenting

BACKGROUND/AIMS

The timing of GpIIb/IIIa inhibitor administration may be important in achieving early epicardial and myocardial reperfusion. We evaluated the effect of early tirofiban on myocardial salvage and cardiovascular outcome in patients with acute myocardial infarction (AMI) undergoing infarct-related artery stenting.

METHODS

Patients (n = 66) with a first AMI presenting <6 h from onset of symptoms were randomized to either early administration of tirofiban in the emergency room (n = 32) or later administration in the catheterization laboratory (n = 34) (tirofiban bolus dose of 10 microg/kg, followed by 0.15 microg/kg for 24 h). The primary end-point was the degree of myocardial salvage, determined by means of serial scintigraphic studies with technetium-99m sestamibi. Thirty-day major adverse cardiac events were also assessed.

RESULTS

There were no significant differences in patient characteristics or in their presentation. The mean door-to-balloon time was similar in both groups (43 +/- 12 and 53 +/- 9 min, p = 0.08). The early and late treatment groups received tirofiban 18 +/- 4 and 52 +/- 10 min after admission, respectively. Angiographic analysis revealed a higher initial frequency of TIMI grade 3 flow in the early group (31% vs. 12%, p = 0.04). Procedural success was achieved in all patients. Myocardial risk area were comparable between early and late treatment groups (35.6 +/- 12.2% vs. 39.3 +/- 14.0%, p = 0.6). Scintigraphic outcomes demonstrated a significant reduction in the final infarction size (11.8 +/- 5.2% vs. 22.4 +/- 6.2%, p = 0.01), and improvement in salvage index (0.68 +/- 0.22 vs. 0.44 +/- 0.18, p = 0.003) in favor of the early tirofiban group. The thirty-day composite end-point of death, recurrent MI or rehospitalization also favored the early group (6% early, 15% late, p = 0.06).

CONCLUSION

Early tirofiban administration enhanced the degree of myocardial salvage and clinical outcome in patients with AMI undergoing infarct-related artery stenting.