Monday, January 11, 2010

Monomorphic Outflow Tract Ventricular Tachycardia: Unique Presenting Manifestation of Gitelman’s Syndrome

Citation : Subba Reddy Vanga, Chandra Annapureddy, Mazda Biria, Dhanunjaya Lakkireddy.Monomorphic Outflow Tract Ventricular Tachycardia: Unique Presenting Manifestation of Gitelman’s Syndrome .JAFIB.2010 January;Volume 1 Issue(10): 606-608.

Outflow Tract Ventricular Tachycardia (OTVT) is typically seen in young to middle aged people with structurally normal hearts. These arrhythmias are triggered by emotional or stress factors and that responds to medications. Electrolyte abnormalities rarely cause ventricular arrhythmia. Gitelman’s syndrome, a rare autosomal recessive renal disorder causes hypokalemia, metabolic alkalosis and hypomagnesaemia. This disorder is often benign with mild clinical symptoms and excellent long-term prognosis. We present a case of Gitelman’s syndrome with symptomatic OTVT as initial manifestation.

Dabigatran, a direct thrombin inhibitor, in atrial fibrillation: Is it already time for a change in oral anticoagulation therapy?

Citation : Osmar Antonio Centurion.Dabigatran, a Direct Thrombin Inhibitor, in Atrial Fibrillation: Is it Already Time for a Change in Oral Anticoagulation Therapy? .JAFIB.2010 January;Volume 1 Issue(10): 601-605.

Atrial fibrillation (AF) is a common arrhythmia, and its prevalence increases with aging and the severity of heart disease. AF affects more than 2 million people in the US, and more than 4 million in Europe. It is expected that the age adjusted prevalence in US will excede 10 million people by the year 2050 . In the last decade, we were able to see the light shed by several trials that dealt with AF mechanisms and the appropriate management of AF patients. Clinical studies have focused mainly on the electrophysiological properties of the substrate in the atrial muscle during sinus rhythm and on the atrial electrical responses elicited by premature stimulation method . However, many fundamental aspects of this arrhythmia have been poorly understood until quite recently, and there are several features on the mechanisms of AF that makes it difficult to manage it properly. Increasing awareness of AF as a disease with possible fatal complications rather than as an acceptable alternative to sinus rhythm has led to search for clear arguments to support a certain strategy as a gold standard.

The State of the Art in Pulmonary Vein Stenosis - Diagnosis & Treatment

Citation : Lourdes R. Prieto.The State of the Art in Pulmonary Vein Stenosis - Diagnosis & Treatment .JAFIB.2010 January;Volume 1 Issue(10): 588-600.

Pulmonary vein stenosis is a rare but serious complication of pulmonary vein isolation to treat atrial fibrillation. Pulmonary vein angioplasty/stenting has emerged as the treatment of choice for significantly stenotic veins. Guidelines for post ablation evaluation of the pulmonary veins, including the timing and method of surveillance for possible stenosis, the criteria for intervention, the technical aspects of intervention, and finally the surveillance post intervention, are still being developed. The relatively high rate of restenosis after intervention in a subset of patients remains a great challenge. A better understanding of the pathophysiology underlying this syndrome is needed to appropriately answer many of the remaining questions. The goal of this manuscript is to describe what has been learned about this complication and its treatment from a relatively large experience in a single institution over the past decade, and provide a comprehensive review of the existing literature in order to shed as much light on the subject as is possible, while at the same time exposing the areas that need further study.

Management of the Asymptomatic Patient After Catheter Ablation of Atrial Fibrillation

Citation : David S. Frankel, Edward P. Gerstenfeld.Management of the Asymptomatic Patient After Catheter Ablation of Atrial Fibrillation .JAFIB.2010 January;Volume 1 Issue(10): 580-587.

Ablative therapy for atrial fibrillation is becoming more commonplace, and some minimally symptomatic or asymptomatic patients will be referred for ablative therapy. Reasons to ablate asymptomatic patients include young age and/or the presence of a tachycardia induced cardiomyopathy; in addition, some symptomatic patients may become asymptomatic after ablation. Managing these patients can be challenging. In this review, we will discuss the use of telemetric monitoring, antiarrhythmic drugs and anticoagulation after ablation in asymptomatic patients with atrial fibrillation.

Abbreviations :
AAD - antiarrhythmic drugs
AF - atrial fibrillation
LVEF - left ventricular ejection fraction
TTM - transtelephonic monitor

C-Reactive Protein and the Risk of Atrial Fibrillation: A Systematic Review and Meta-Analysis

Citation : Venkata M Alla, Senthil Thambidorai, Kishlay Anand, Aryan N Mooss, Richard Baltaro, Syed M Mohiuddin.C-Reactive Protein and the Risk of Atrial Fibrillation: A Systematic Review and Meta-Analysis .JAFIB.2010 January;Volume 1 Issue(10): 569-579.

There is increasing evidence linking C-reactive protein (CRP) and atrial fibrillation (AF). Despite the abundance of literature, confusion exists regarding this association because of inconsistent results. MEDLINE and Cochrane Controlled Trials Register databases were carefully searched through July, 2007 combining the following terms “C-reactive protein” and “atrial fibrillation”. Of the 106 studies initially identified, 7 studies with 7349 subjects (638 with AF) were included in the meta-analysis. Analysis yielded a relative risk of 1.51 (1.24, 1.84) for occurrence of AF when CRP level was above a cut off of 3-3.5 mg/l. When 2 studies with data on a higher cut off of 4.5-5.0 mg/l were analyzed separately, the relative risk was 4.03 (2.6, 6.2). Our study suggests that elevated CRP increases the relative risk for AF. The risk appears incremental with higher CRP levels conferring proportionately increased risk. There is an urgent need for further large scale well designed studies.

Level of natriuretic peptide Determines outcome in atrial fibrillation

Citation : Qi-xian Zeng, Ming-fen Wei, Wei Zhang, Yun Zhang, Jing-quan Zhong.Level of natriuretic peptide Determines outcome in atrial fibrillation .JAFIB.2010 January;Volume 1 Issue(10): 559-568.

Background : Natriuretic peptide (NP) is high in atrial fibrillation (AF)and may decrease after cardioversion to sinus rhythm and the levels of atrial NP (ANP) and brain NP (BNP) in different types of AF and whether ANP and BNP have predictive values for relapsed AF have not been determined.
Purpose: We aimed to examine the levels of ANP and BNP in AF to determine their roles in different types of AF, including a predictive value in relapsed AF.
Methods and Results : ANP and BNP were measured in 100 consecutive patients with AF and without heart dysfunction at baseline and in 20 controls. All patients had higher levels than controls (p<0.01). After cardioversion treatment with antiarrhythmic therapy, 40 patients failed to cardiover cardioversion successfully and still showed AF, whereas 60 patients were successful. ANP and BNP levels decreased significantly after cardioversion (163.55±54.27pg/ml vs. 200.20±55.63 pg/ml; 124.15±43.00 pg/ml vs. 161.99±48.04 , for ANP and BNP respectively, both p<0.0001). 18 of the 60 successfully cardioverted patients had AF recurred within 24 hours, who were then excluded from 500-day follow-up and the remaining 42 patients were enrolled. During 500-day follow-up period, AF relapsed in 16 patients. Comparing with the 42 patients, the 16 patients showed higher concentrations of ANP (187.72±32.79 pg/ml vs. 138.42±30.65 pg/ml, p<0.0001). Besides, both ANP and BNP were significantly higher in the relapsed patients than those remained SR during follow-up (153.38±29.6 pg/ml vs. 129.21±27.98 pg/ml for ANP, p=0.01 and 147.41±25.95 pg/ml vs. 121.87±20.53pg/ml for BNP, p=0.001). The area under the receiver-operating characteristic curve was 0.799 for BNP and 0.706 for ANP in predicting a relapse of AF. Using the BNP optimized cut-off level of 138 pg/ml, relapsed AF can be predicted with relatively acceptable accuracy.
Conclusions : ANP and BNP decrease significantly after cardioversion in patients with AF, and both can be useful predictors of relapsed AF.
Key Words: Atrial fibrillation; ardioversion; ANP; BNP; relapse of atrial fibrillation