Left atrial “stunning” following radiofrequency catheter ablation of chronic atrial flutter

Objectives. This study examined the effect of radiofrequency ablation (RFA) on left atrial (LA) and left atrial appendage (LAA) function in humans with chronic atrial flutter (AFL).Background. Atrial stunning and the development of spontaneous echocardiographic contrast (SEC) is a consequence of electrical cardioversion of AFL to sinus rhythm. This phenomenon has been termed “stunning” and is associated with thrombus formation and embolic stroke. Radiofrequency ablation is now considered to be definitive treatment for chronic AFL, but whether this procedure is complicated by LA stunning is unknown.Methods. Fifteen patients with chronic AFL undergoing curative RFA underwent transesophageal echocardiography to evaluate LA and LAA function and SEC before and immediately, 30 minutes and 3 weeks after RFA. To control for possible direct effects of RFA on atrial function, seven patients undergoing RFA for paroxysmal AFL were also studied. In this group, RF energy was delivered in sinus rhythm and echocardiographic parameters were assessed before and immediately and 30 minutes following RFA.Results. Chronic AFL: Mean arrhythmia duration was 17.2 ± 13.3 months. Twelve patients (80%) developed SEC following RF energy application and reversion to sinus rhythm. LAA velocities decreased significantly from 54.0 ± 14.2 cm/s in AFL to 18.0 ± 7.1 cm/s in sinus rhythm after arrhythmia termination (p < 0.01). These changes persisted for 30 minutes. Following 3 weeks of sustained sinus rhythm, significant improvements in LAA velocities (68.9 ± 23.6 vs. 18.0 ± 7.1 cm/s, p < 0.01) and mitral A-wave velocities (49.8 ± 10.3 vs. 13.4 ± 11.2 cm/s, p < 0.01) were evident and SEC had resolved in all patients. Paroxysmal AFL: Radiofrequency energy delivered in sinus rhythm had no significant effect on any of the above indexes of LA or LAA function and no patient developed SEC following RFA.Conclusions. Radiofrequency ablation of chronic AFL is associated with significant LA stunning and the development of SEC. Left atrial stunning is not secondary to the RF energy application itself. Sustained sinus rhythm for 3 weeks leads to resolution of these acute phenomena. Left atrial stunning occurs in the absence of direct current shock or antiarrhythmic drugs, suggesting that its mechanism may be a function of the preceding arrhythmia rather than the mode of reversion.     

Immunomodulatory treatment for lymphocytic myocarditis—a systematic review and meta-analysis

Deleterious inflammatory responses are seen to be the trigger of heart failure in myocarditis and therapies directed towards immunomodulation have been assumed to be beneficial. The objective of the present review was to systematically assess the effect of immunomodulation in lymphocytic myocarditis. Studies were included if diagnosis of lymphocytic myocarditis was based on EMB as well as on the exclusion of other etiologies of heart failure and if the patients had at least moderately decreased left ventricular ejection fraction (<?45%). All immunomodulatory treatments at any dose that target the cause of myocarditis leading to cardiomyopathy were included. Retrieval of PUBMED, SCOPUS, Cochrane Central Register of Controlled Trials, and LILACs from January 1950 to January 2016 revealed 444 abstracts of which nine studies with a total of 612 patients were included. As primary effectivity endpoint, a change in left ventricular ejection was chosen. No benefits of corticosteroids or intravenous immunoglobulin alone were reported. Immunoadsorption and subsequent IVIG substitution was associated with a greater improvement in left ventricular ejection fraction (LVEF) in one study. Single studies found a beneficial effect of interferon and statins on LVEF. We performed a meta-analysis for the combination of corticosteroids with immunosuppressants and found a non-significant increase of LVEF of +?13.06% favoring combined treatment (95%CI 1.71 to +?27.84%, p?= 0.08). The current evidence does not support the routine use of immunosuppression in traditional lymphocytic myocarditis. Nevertheless, in histologically proven virus-negative myocarditis of high-risk patients, combined immunosuppression might be beneficial. Future research should focus on translation of these effects to clinical outcome.     

Disease-modifying anti-rheumatic drugs for the management of Takayasu arteritis—a systematic review and meta-analysis

The pharmacotherapy of Takayasu arteritis (TAK) with disease-modifying anti-rheumatic drugs (DMARDs) is an evolving area. A systematic review of Scopus, Web of Science, Pubmed Central, clinical trial databases and recent international rheumatology conferences for interventional and observational studies reporting the effectiveness of DMARDs in TAK identified four randomized controlled trials (RCTs, with another longer-term follow-up of one RCT) and 63 observational studies. The identified trials had some concern or high risk of bias. Most observational studies were downgraded on the Newcastle-Ottawa scale due to lack of appropriate comparator groups. Studies used heterogenous outcomes of clinical responses, angiographic stabilization, normalization of inflammatory markers, reduction in vascular uptake on positron emission tomography, reduction in prednisolone doses and relapses. Tocilizumab showed benefit in a RCT compared to placebo in a secondary per-protocol analysis but not the primary intention-to-treat analysis. Abatacept failed to demonstrate benefit compared to placebo for preventing relapses in another RCT. Pooled data from uncontrolled observational studies demonstrated beneficial clinical responses and angiographic stabilization in nearly 80% patients treated with tumour necrosis factor alpha inhibitors, tocilizumab or leflunomide. Certainty of evidence for outcomes from RCTs ranged from moderate to very low and was low to very low for all observational studies. There is a paucity of high-quality evidence to guide the pharmacotherapy of TAK. Future observational studies should attempt to include appropriate comparator arms. Multicentric, adequately powered RCTs assessing both clinical and angiographic responses are necessary in TAK.

     

Safety and efficacy of the remote magnetic navigation for ablation of ventricular tachycardias—a systematic review

Objective

Remote magnetic navigation (RMN) is considered to be a solution for mapping and ablation of several arrhythmias. In this systematic review we aimed to assess the safety and efficacy of RMN in ablation of ventricular tachycardia (VT).

Methods

The National Library of Medicine??s PubMed database was searched for articles containing any of a predetermined set of search terms that were published prior to November 1, 2011. Quality of evidence was rated using the GRADE system.

Results

The database search resulted in 11 relevant articles evaluating the usefulness of RMN. Three groups of VTs were studied: VT in patients with ischemic cardiomyopathy (ICMP), non-ischemic cardiomyopathy (NICMP) and structurally normal hearts (SNH). The use of RMN in patients with ICMP has been associated with success rates ranging from 71 to 80%. RMN has been shown to be a feasible and effective method for ablation of VT in NICMP and SNH patients. Success rates between 50% and 100% have been reported in NICMP populations. Rates ranging from 86% to 100% have been reported for SNH patients. The lowest rates of arrhythmia recurrence are reported for SNH patients (0?C17%). In ICMP and NICMP, recurrence rates of 0?C30% and 14?C50%, respectively, have been reported. One patient experienced total heart block, and one patient experienced a thromboembolic event after RMN catheter ablation procedures.

Conclusions

RMN has been shown to be an effective and safe method for ablation of VT in various patient populations with low recurrence and complication rates. However, more comparative and randomized studies are necessary, and therefore the true value of RMN for VT ablation remains still unknown.     

Clinical follow-up of left atrial appendage occlusion in patients with atrial fibrillation ineligible of oral anticoagulation treatment—a systematic review and meta-analysis

Journal of Interventional Cardiac Electrophysiology - The recommended stroke prevention for patients with atrial fibrillation (AF) and increased risk of ischemic stroke is oral anticoagulation...     

Clinical evaluation of a novel 12-hole irrigated tip catheter ablation system for the treatment of typical atrial flutter—results from the Duo FLAIR clinical study

Introduction

Higher current density at the proximal end of a six-hole catheter is not irrigated and thus could lead to uneven heating and possibly coagulum and charring. This study tested a novel 12-hole irrigated catheter with six additional holes at the proximal end that provides more uniform cooling during atrial flutter (AFL) ablation.

Methods

A total of 188 patients (28 females, 66?±?11 years) were treated for typical AFL at 22 sites in the USA and Canada using Cool Path Duo at 50 W and 45 °C at an irrigation rate of 13 ml/min. The results were compared to historical data from an AFL study which used a six-hole catheter with similar design.

Results

A total of 2,725 RF lesions were applied in 188 patients with a mean RF duration of 18.2?±?11.7 min per procedure. Procedural success was achieved in 96.3 % (181 of 188) acutely and 98.3 % (173 of 176) patients at 3 months. Steam pops occurred in 0.6 % of lesions (15 of 2,725) without coagulum or charring… Compared to the six-hole irrigated tip catheter, the Cool Path Duo catheter delivered more power (33.8?±?5.9 vs. 29.7?±?5.2 W, p?<?0.0001) at a lower average tip temperature (34.7?±?1.5 vs. 37.2?±?2.1 °C, p?<?0.0001) with no statistical differences in either 3-month AFL recurrence or complications.

Conclusion

Cool Path Duo? irrigated tip catheter is safe and effective in treating typical AFL. When compared to a six-hole irrigated tip catheter, the Cool Path Duo catheter delivers more power at a lower temperature.     

Outcomes of pituitary surgery for Cushing’s disease: a systematic review and meta-analysis

Pituitary - Transsphenoidal surgery (TSS) is the first-line treatment for Cushing’s disease (CD). This review aimed to synthesize the remission and recurrence rates following TSS for CD and...     

Effectiveness of medical treatment for Cushing’s syndrome: a systematic review and meta-analysis

Purpose

To systematically review the effectiveness of medical treatment for Cushing’s syndrome in clinical practice, regarding cortisol secretion, clinical symptom improvement, and quality of life. To assess the occurrence of side effects of these medical therapies.

Methods

Eight electronic databases were searched in March 2017 to identify potentially relevant articles. Randomized controlled trials and cohort studies assessing the effectiveness of medical treatment in patients with Cushing’s syndrome, were eligible. Pooled proportions were reported including 95% confidence intervals.

Results

We included 35 articles with in total 1520 patients in this meta-analysis. Most included patients had Cushing’s disease. Pooled reported percentage of patients with normalization of cortisol ranged from 35.7% for cabergoline to 81.8% for mitotane in Cushing’s disease. Patients using medication monotherapy showed a lower percentage of cortisol normalization compared to use of multiple medical agents (49.4 vs. 65.7%); this was even higher for patients with concurrent or previous radiotherapy (83.6%). Mild side effects were reported in 39.9%, and severe side effects were seen in 15.2% of patients after medical treatment. No meta-analyses were performed for clinical symptom improvement or quality of life due to lack of sufficient data.

Conclusions

This meta-analysis shows that medication induces cortisol normalization effectively in a large percentage of patients. Medical treatment for Cushing’s disease patients is thus a reasonable option in case of a contraindication for surgery, a recurrence, or in patients choosing not to have surgery. When experiencing side effects or no treatment effect, an alternate medical therapy or combination therapy can be considered.

     

Presentation and clinical course of pediatric-onset versus adult-onset Takayasu arteritis—a systematic review and meta-analysis

Clinical Rheumatology - Takayasu arteritis (TAK) is a less common large-vessel vasculitis which can occur in either children or adults. However, differences between pediatric-onset and adult-onset...     

The effectiveness of treatments for Kashin–Beck disease: a systematic review and network meta-analysis

Clinical Rheumatology - This study aims to evaluate the efficacy of treatments for Kashin–Beck disease (KBD). We searched PubMed, Cochrane Central Register of Controlled Trials, Embase, Web...     

Changing coronary sinus activation during catheter ablation of isthmus-dependent right atrial flutter: what is the mechanism?

A 69-year-old woman was referred for cavotricuspid isthmus ablation due to typical isthmus-dependent right atrial flutter. During ablation, intracardiac activation sequence in coronary sinus (CS) changed without altering the cycle length or the P-wave morphology. This suggests that interatrial connection via CS was blocked and left atrium (LA) was activated from Bachmann's bundle or/and connections between fossa ovalis and LA.