Use of Ivabradine in Postural Orthostatic Tachycardia Syndrome

Citation : Jamil-Copley S, Nagarajan DV, Baig MK.Use of Ivabradine in Postural Orthostatic Tachycardia Syndrome .JAFIB.2010 May;Volume 2 Issue(1): 745-746.

Postural orthostatic tachycardia syndrome (POTS) is characterized by inappropriate increase in heart rate on assuming upright position from a supine position without a necessary drop in blood pressure. Etiology of this condition is complex and multifactorial. Autonomic dysfunction, hypovolemia, hyper responsiveness of beta adrenergic receptors with associated elevations of plasma norepinephrine levels have been implicated as underlying pathophysiologic mechanisms. Beta blockers have previously been used to treat this condition. Ivabradine which selectively inhibits If ion current in the sino atrial node, has been reported to be useful in patients with POTS. We present one further such case of POTS successfully treated by Ivabradine.

Supraventricular Ectopic Activity: When Excessive it is not all Benign!

Citation : Tuan Le Nguyen, Liza Thomas.Supraventricular Ectopic Activity: When Excessive it is not all Benign! .JAFIB.2010 May;Volume 2 Issue(1): 742-744.

Stroke is a significant cause of mortality and disabling morbidity. The major subtypes of stroke are divided into thrombo-embolic, haemorrhagic and cryptogenic, with each having different predisposing risk factors and management strategies. Atrial fibrillation (AF) is the commonest arrhythmia predisposing to thrombo-embolic stroke. The incidence of AF increases with age, affecting up to 5% in the elderly population. Electrophysiology studies have implicated that spontaneous atrial ectopic beats that originate in or near pulmonary veins adjacent to the left atrium, may initiate paroxysms of AF.

Commentary on : New-Onset Atrial Fibrillation Predicts Long-Term Mortality After Coronary Artery Bypass Graft by El-chami et.al

Citation : Giovanni Filardo.Commentary on : New-Onset Atrial Fibrillation Predicts Long-Term Mortality After Coronary Artery Bypass Graft by El-chami et.al .JAFIB.2010 May;Volume 2 Issue(1): 740-741.

El-Chami and colleagues report that new-onset post-operative atrial fibrillation (AF) is associated with a significant reduction in long-term survival (adjusted hazard ratio: 1.21; 95% confidence interval: 1.12 to 1.32; follow-up: mean 6 years, range: 0 to 12.5 years) for patients undergoing isolated coronary artery bypass grafting (CABG). Moreover, the authors suggest that patients with new-onset post-CABG AF discharged on warfarin experienced reduced mortality during follow-up (adjusted HR: 0.78, 95% CI: 0.66 to 0.92) when compared to those who were not discharged on warfarin.

Is AF Ablation Cost Effective?

Citation :
William Martin-Doyle, Matthew R. Reynolds.Is AF Ablation Cost Effective? .JAFIB.2010 May;Volume 2 Issue(1): 727-739.

The use of catheter ablation to treat AF is increasing rapidly, but there is presently an incomplete understanding of its cost-effectiveness. AF ablation procedures involve significant up-front expenditures, but multiple randomized trials have demonstrated that ablation is more effective than antiarrhythmic drugs at maintaining sinus rhythm in a second-line and possibly first-line rhythm control setting. Although truly long-term data are limited, ablation, as compared with antiarrrhythmic drugs, also appears associated with improved symptoms and quality of life and a reduction in downstream hospitalization and other health care resource utilization. Several groups have developed cost effectiveness models comparing AF ablation primarily to antiarrhythmic drugs and the model results suggest that ablation likely falls within the range generally accepted as cost-effective in developed nations. This paper will review available information on the cost-effectiveness of catheter ablation for the treatment of atrial fibrillation, and discuss continued areas of uncertainty where further research is required.

Invasive Management of Atrial Fibrillation and the Elderly

Citation : Sandeep M. Patel, Samuel J. Asirvatham.Invasive Management of Atrial Fibrillation and the Elderly .JAFIB.2010 May;Volume 2 Issue(1): 715-726

Atrial fibrillation (AF) is the most common arrhythmia encountered by caregivers for the elderly. A plethora of new, mostly invasive techniques have evolved to treat patients who remain symptomatic from this arrhythmia despite attempts at pharmacological therapy. The most widely-used of these new techniques is radiofrequency ablation, but in select patients, special types of pacemaker, cryoablation, and surgical maze therapy may be of benefit.

Ranolazine for Atrial Fibrillation: Too Good to be True?

Citation : Joseph J. Gard, Samuel J. Asirvatham. Ranolazine for Atrial Fibrillation: Too Good to be True? .JAFIB.2010 May;Volume 2 Issue(1): 711-714.

Several management options for patients with symptomatic atrial fibrillation (AF) available today were not even in the realm of discussion two decades ago. These advances, however, have primarily involved invasive management options for patients with drug refractory arrhythmia. After the recognition that electrical isolation of the thoracic veins benefits patients with paroxysmal AF, a slew of more involved ablative techniques evolved. Major breakthroughs in antiarrhythmic therapy, however, have not paralleled this meteoric development of invasive techniques. The drive for invasive procedures has, in fact, been widely based on the lack of availability of simple, effective, and safe pharmacological options for AF. The introduction of dronedarone into clinical practice represented a recent addition to antiarrhythmic therapy options for use in the management of patients with AF. This agent is an analogue of amiodarone but devoid of the iodine moiety which allows its use without the well-recognized and dreaded organ toxicity associated with long-term use. Nevertheless, a significant need exists for a drug with limited side effects that can be used for symptomatic intermittent AF without the need for daily chronic use, fear of organ toxicity, and concern regarding proarrhythmia in patients with structural heart disease.

The Conversion of Paroxysmal or Initial Onset Atrial Fibrillation with Oral Ranolazine: Implications for a New "Pill-In-Pocket" Approach in Structural

Citation : David K. Murdock, James A Reiffel, Jeff Kaliebe, German Larrain.The Conversion of Paroxysmal or Initial Onset Atrial Fibrillation with Oral Ranolazine: Implications for a New "Pill-In-Pocket" Approach in Structural Heart Disease .JAFIB.2010 May;Volume 2 Issue(1): 705-710.

Background: The "Pill-in-Pocket" (PIP) is an approach to atrial fibrillation (AF) where oral anti-arrhythmics at 75% to 100% of the normal daily dose, given as a single dose, is used to convert recent-onset AF. Pro-arrhythmic risk has limited this approach to patients without structural heart disease (SHD). Ranolazine is an anti-anginal agent, which inhibits the abnormal late Na+ channel current resulting in decreased Na+/Ca++ overload. This inhibits after-depolarizations and reduces pulmonary vein firing, which have been implicated in the initiation and propagation of AF. Ranolazine increases atrial refractoriness and has no known pro-arrhythmic affects. Ranolazine is routinely given to patients with SHD. The ability of Ranolazine to terminate AF in man has not been described but if useful could be a safer PIP agent with application in the presence or absence of SHD. We describe our experience using oral Ranolazine to convert new or recurrent AF.
Method: 2000 mg of ranolazine was administered to 35 patients with new (16 patients) or recurrent (19 patients) AF of at least 3 but not greater than 48 hours duration. Clinical features, echocardiographic data, and SHD were noted. Success was defined as restoring sinus rhythm within 6 hours of Ranolazine.
Results: All but 4 patients had some form of SHD. Twenty-five patients were in the hospital, 5 were in the office, and 5 were at home at the time Ranolazine was administered. Twenty-five of 35 patients converted to sinus rhythm. No pro-arrhythmic effects, hemodynamic instability, adverse rate effects, or perceived intolerance were noted. The 71% conversion rate was comparable to other reported PIP protocols and much higher than reported placebo conversion rates.
Conclusion: High dose oral Ranolazine shows utility as a possible safe agent to convert new or recurrent AF. Larger placebo-controlled studies would appear to be warranted.