Atrial Fibrillation in Heart Failure:

Rhythm control for patients with atrial fibrillation complicated with heart failure in the contemporary era of catheter ablation: a stratified pooled analysis of randomized data

Aims

The optimal treatment for patients with atrial fibrillation (AF) and heart failure (HF) has been a subject of debate for years. We aimed to evaluate the efficacy and safety of rhythm control strategy in patients with AF complicated with HF regarding hard clinical endpoints.

Methods and results

Up-to-date randomized data comparing rhythm control using antiarrhythmic drugs (AADs) vs. rate control (Subset A) or rhythm control using catheter ablation vs. medical therapy (Subset B) in AF and HF patients were pooled. The primary outcomes were all-cause mortality, re-hospitalization, stroke, and thromboembolic events. A total of 11 studies involving 3598 patients were enrolled (Subset A: 2486; Subset B: 1112). As compared with medical rate control, the AADs rhythm control was associated with similar all-cause mortality [odds ratio (OR): 0.96, P = 0.65], significantly higher rate of re-hospitalization (OR: 1.25, P = 0.01), and similar rate of stroke and thromboembolic events (OR: 0.91, P = 0.76,); however, as compared with medical therapy, catheter ablation rhythm control was associated with significantly lower all-cause mortality (OR: 0.51, P = 0.0003), reduced re-hospitalization rate (OR: 0.44, P = 0.003), similar rate of stroke events (OR: 0.59, P = 0.27), greater improvement in left ventricular ejection fraction [weighted mean difference (WMD): 6.8%, P = 0.0004], lower arrhythmia recurrence (29.6% vs. 80.1%, OR: 0.04, P < 0.00001), and greater improvement in quality of life (Minnesota Living with Heart Failure Questionnaire score) (WMD: −9.1, P = 0.007).

Conclusion

Catheter ablation as rhythm control strategy substantially improves survival rate, reduces re-hospitalization, increases the maintenance rate of sinus rhythm, contributes to preserve cardiac function, and improves quality of life for AF patients complicated with HF.

Atrial Fibrillation in Heart Failure Patients with Preserved or Reduced Ejection Fraction. Prognostic significance of Rhythm control strategy with Catheter Ablation

Introduction

Atrial fibrillation (AF) and heart failure (HF) often coexist with an increase in morbidity and mortality. AF catheter ablation (CA) has proved to be a safe and efficient option for HF patients, but long-term evolution and prognosis remain uncertain. The aim is to assess the efficacy and safety of CA in HF patients with AF, and analyze HF long-term evolution.

Methods

We prospectively analyzed consecutive patients with AF and congestive HF or left ventricular ejection fraction (EF) less than 45%, who underwent CA of AF between 2011 and 2016. We excluded patients who did not complete one year of follow-up.

Results

Seventy-nine patients were included. Mean age was 62.1 years, 72.4% were men, 67.2% had hypertension and 8.6% were diabetics. Mean EF was 49%, left atrial area was 26.5 cm2 and mean CHA2DS2-VASc score was 2. 70.6% were on NYHA FC II-III.The recurrence rate of AF was 60%, and after a second CA the rate decreased to 27.8%. Only persistent AF prior to the procedure was identified as independent predictor of recurrence. There was a significant NYHA FC improvement in the sinus rhythm (SR) group vs those with recurrence (63.6% vs 36.4%; p=0.047). None of the patients in SR were hospitalized, whereas six with recurrence were hospitalized due to HF (0% vs. 18.2%; p = 0.07). The rate of complications was 9.1%.

Conclusions

Catheter ablation of atrial fibrillation in heart failure presents an adequate success rate, improving symptoms and reducing rehospitalizations due to heart failure.

Update on Bayés' syndrome: the association between an interatrial block and supraventricular arrhythmias

INTRODUCTION

The past few years have given rise to extensive research on an interatrial block and its clinical relevance, mainly its association with supraventricular arrhythmias. In 2015, the authors of this article reviewed the Bayes syndrome for the first time and after three years there has been so much evidence accumulated that it seems reasonable to rewrite an update, based fundamentally on the new findings. Focused on its relationship with cardioembolic strokes, today efforts are being targeted at understanding its pathophysiology, its diagnosis, and its prognostic implications, in order to learn if it should be treated. Areas covered: A non-systematic review of the literature was developed using the Pubmed and Cochrane databases, focusing on randomized clinical trials and large observational studies that evaluated new physiopathological and epidemiological aspects, new clinical scenarios in which it has been assessed and its association with dementia. Finally, those studies that proposed new possible treatments were reviewed. Expert commentary: Interatrial block is not only a predictor of supraventricular arrhythmias, is a subclinical disease that might be considered as a marker of risk for adverse outcomes. Although there is some evidence to suggest that early treatment may be beneficial, potential therapies have yet to be investigated.

Influence of energy source on early atrial fibrillation recurrences: a comparison of cryoballoon vs. radiofrequency current energy ablation with the endpoint of unexcitability in pulmonary vein isolation

Introduction

Comparative data of early recurrence rates of atrial fibrillation (ERAF) following second-generation cryoballoon (CB-G2) and radiofrequency current (RFC) ablation for pulmonary vein isolation (PVI) in paroxysmal AF (PAF) are rare. We randomized PAF patients into either PVI with CB-G2 (group 1) or PVI with a combined RFC-approach applying contact force (CF) with the endpoint of unexcitability (group 2) to investigate ERAF.

Methods and results

In group 1 (n = 30), CB-G2-PVI was performed. After CF-PVI in group 2 (n = 30), bipolar pacing on the ablation line and additional ablation until unexcitability was conducted. Follow-up included 48 h of in-hospital monitoring followed by 5-day Holter ECGs 1, 2, 3, 6, 12 months postablation to evaluate ERAF. Acute PVI was reached in 100% of group 2 and in 99% of group 1. Shorter procedure durations (98.0 ± 21.9 vs. 114.3 ± 18.7 min, P < 0.05) but extended fluoroscopy times (15.4 ± 3.9 vs. 10.0 ± 4.3 min, P < 0.05) were found in the CB-G2 group. Ten non-severe complications occurred (6 vs. 4 in group 1 and 2, P = 0.73). In group 2, five patients suffered from ERAF vs. seven patients in group 1 (P = 0.67). The time until the occurrence of ERAF was shorter in group 2 (1 day (q1-q3: 1-4.5)) when compared with group 1 (22 (q1-q3: 6-54) days, P = 0.025).

Conclusion

ERAF rates were equal among groups; however, they occurred earlier in the initial phase after RFC ablation when compared with CB-G2. PVI utilizing cryoablation is associated with shorter procedure durations but extended fluoroscopy time while being similarly secure.

Meta-analysis of randomized controlled trials on atrial fibrillation ablation in patients with heart failure with reduced ejection fraction

BACKGROUND

The role of catheter ablation (CA) is increasingly recognized as a reasonable therapeutic option in patients with atrial fibrillation (AF) and heart failure (HF).

HYPOTHESIS

We aimed to compare CA to medical therapy in AF patients with HF with reduced ejection fraction (HFrEF).

METHODS

We searched the literature for randomized clinical trials comparing CA to medical therapy in this population.

RESULTS

Six trials with a total of 775 patients were included. AF was persistent in 95% of patients with a mean duration of 18.5 ± 23 months prior enrollment. The mean age was 62.2 ± 7.8 years, mostly males (83%) with mean left ventricular ejection fraction (LVEF) of 31.2 ± 6.7%. Compared to medical therapy, CA has significantly improved LVEF by 5.9% (Mean difference [MD] 5.93, confidence interval [CI] 3.59-8.27, P < 0.00001, I²  = 87%), quality of life, (MD -9.01, CI -15.56, -2.45, P = 0.007, I² = 47%), and functional capacity (MD 25.82, CI 5.46-46.18, P = 0.01, I² = 90%). CA has less HF hospital readmissions (odds ratio [OR] 0.5, CI 0.32-0.78, P = 0.002, I² = 0%) and death from any cause (OR 0.46, CI 0.29-0.73, P = 0.0009, I² = 0%). Freedom from AF during follow-up was higher in patients who had CA (OR 24.2, CI 6.94-84.41, P < 0.00001, I² = 81%.

CONCLUSION

CA was superior to medical therapy in patients with AF and HFrEF in terms of symptoms, hemodynamic response, and clinical outcomes by reducing AF burden. However, these findings are applicable to the very specific patients enrolled in these trials.

Advanced interatrial block predicts new-onset atrial fibrillation and ischemic stroke in patients with heart failure: The "Bayes' Syndrome-HF" study

AIMS

Advanced interatrial block (IAB) is characterized by a prolonged (≥120 ms) and bimodal P wave in the inferior leads. The association between advanced IAB and atrial fibrillation (AF) is known as "Bayes' Syndrome", and there is scarce information about it in heart failure (HF). We examined the prevalence of IAB and whether advanced IAB could predict new-onset AF and/or stroke in HF patients.

METHODS AND RESULTS

The prospective observational "Bayes' Syndrome-HF" study included consecutive outpatients with chronic HF. The primary endpoints were new-onset AF, ischemic stroke, and the composite of both. A secondary endpoint included all-cause death alone or in combination with the primary endpoint. Comprehensive multivariable Cox regression analyses were performed. Among 1050 consecutive patients, 536 (51.0%) were in sinus rhythm, 464 with a measurable P wave are the focus of this study. Two-hundred and sixty patients (56.0%) had normal atrial conduction, 95 (20.5%) partial IAB, and 109 (23.5%) advanced IAB. During a mean follow-up of 4.5 ± 2.1 years, 235 patients experienced all-cause death, new-onset AF, or stroke. In multivariable comprehensive Cox regression analyses, advanced IAB was associated with new-onset AF (HR 2.71 [1.61-4.56], P < 0.001), ischemic stroke (HR 3.02 [1.07-8.53], P = 0.04), and the composite of both (HR 2.42 [1.41-4.15], P < 0.001).

CONCLUSIONS

In patients with HF advanced IAB predicts new-onset AF and ischemic stroke. Future studies must assess whether anticoagulant treatment in Bayes' Syndrome leads to better outcomes in HF.

Addressing Multimorbidity and Polypharmacy in Individuals With Atrial Fibrillation

PURPOSE OF REVIEW

The objectives of this review were to (1) discuss how multimorbidity and polypharmacy contributes to the complexity of management among individuals with AF and (2) identify any interventions to manage polypharmacy in relation to AF.

RECENT FINDINGS

Based on the four landmark clinical trials of novel anticoagulants, the most common comorbidities with AF are hypertension, heart failure, diabetes, stroke and myocardial infarction. Polypharmacy was also found prevalent in 76.5% of patients with AF, with a median of six drugs per patient. Despite the consequences of polypharmacy in AF, there is very little evidence-based intervention designed to manage it. Hence, there is a need for further research to examine interventions to manage polypharmacy in relation to AF. Atrial fibrillation (AF) is the most common type of cardiac arrhythmia requiring treatment in adults. Due to the structural and/or electrophysiological abnormalities that occur in AF, patients are managed through the use of prophylactic anticoagulant and rate and/or rhythm control medications. However, these medications are considered high risk and can increase the chances of medication misadventure. Additionally, AF rarely occurs in isolation and is known to coexist with multiple other medical comorbidities, i.e. multimorbidity. This also increases the number of medications, i.e. polypharmacy and pill burden which results in treatment non-compliance to prescribed therapy.

Advanced Interatrial Block Predicts New Onset Atrial Fibrillation in Patients with Severe Heart Failure and Cardiac Resynchronization Therapy

BACKGROUND

Advanced interatrial block (aIAB) on the surface electrocardiogram (ECG), defined as a P-wave duration ≥120 milliseconds with biphasic (±) morphology in inferior leads, is frequently associated with atrial fibrillation (AF). The aim of this study was to determine whether preoperative aIAB could predict new-onset AF in patients with severe congestive heart failure (CHF) requiring cardiac resynchronization therapy (CRT).

METHODS

Retrospective analysis of consecutive patients with CHF and no prior history of AF undergoing CRT for standard indications. A baseline 12-lead ECG was obtained prior to device implantation and analyzed for the presence of aIAB. ECGs were scanned at 300 DPI and maximized 8×. Semiautomatic calipers were used to determine P-wave onset and offset. The primary outcome was the occurrence of AF identified through analyses of intracardiac electrograms on routine device follow-up.

RESULTS

Ninety-seven patients were included (74.2% male, left atrial diameter 45.5 ± 7.8 mm, 63% ischemic). Mean P-wave duration was 138.5 ± 18.5 milliseconds and 37 patients (38%) presented aIAB at baseline. Over a mean follow-up of 32 ± 18 months, AF was detected in 29 patients (30%) and the incidence was greater in patients with aIAB compared to those without it (62% vs 28%; P < 0.003). aIAB remained a significant predictor of AF occurrence after multivariate analysis (OR 4.1; 95% CI, 1.6-10.7; P < 0.003).

CONCLUSION

The presence of aIAB is an independent predictor of new-onset AF in patients with severe CHF undergoing CRT.

Impairment of pulmonary function is an independent risk factor for atrial fibrillation: the Takahata study

BACKGROUND

Chronic pulmonary disorders, such as chronic obstructive pulmonary disease (COPD) and fibrosing lung diseases, and atrial fibrillation (AF), are prevalent in elderly people. The impact of cardiac co-morbidities in the elderly, where pulmonary function is impaired, cannot be ignored as they influence mortality. The relationship between the prevalence of AF and pulmonary function is unclear. The aim of this study was to evaluate this relationship in participants in a health check.

METHODS

Subjects aged 40 or older (n = 2,917) who participated in a community-based annual health check in Takahata, Japan, from 2004 through to 2005, were enrolled in the study. We performed blood pressure measurements, blood sampling, electrocardiograms, and spirometry on these subjects.

RESULTS

The mean FEV(1) % predicted and FVC % predicted in AF subjects was significantly lower than in non-AF subjects. The prevalence of AF was higher in those subjects with airflow limitation or lung restriction than in those without. Furthermore, AF prevalence was higher in those subjects with severe airflow obstruction (FEV(1) %predicted < 50) than in those who had mild or moderate airflow obstruction (FEV(1) %predicted ≥ 50), although there was no difference between the prevalence of AF in subjects with 70≤ FVC %predicted <80 lung restriction and those with FVC %predicted <70. Multiple logistic regression analysis revealed that FEV(1) %predicted and FVC %predicted are independent risk factors for AF (independent of age, gender, left ventricular hypertrophy, and serum levels of B-type natriuretic peptide).

CONCLUSION

Impaired pulmonary function is an independent risk factor for AF in the Japanese general population.

Atrial fibrillation and congestive heart failure

PURPOSE OF REVIEW

The present review will examine the prognostic importance of atrial fibrillation and heart failure, explore the different therapeutic options for treating atrial fibrillation and present the results of the Atrial Fibrillation and Congestive Heart Failure (AF-CHF) trial.

RECENT FINDINGS

The Atrial Fibrillation and Congestive Heart Failure trial was a randomized trial involving patients with both atrial fibrillation and heart failure. The trial was designed to compare the maintenance of sinus rhythm with the control of ventricular rate in patients with left ventricular dysfunction, heart failure and a history of atrial fibrillation. There was no significant difference in the rate of death from cardiovascular causes in the rhythm-control group as compared with the rate-control strategy. In addition, there was no significant difference in any of the secondary outcomes including death from any cause, worsening heart failure or stroke. The rate-control strategy eliminated the need for repeated cardioversion and reduced rates of hospitalization.

SUMMARY

The results of the Atrial Fibrillation and Congestive Heart Failure trial indicate that a routine strategy of rhythm control does not reduce rate of death and suggest that rate control should be considered a primary approach for patients with atrial fibrillation and heart failure.

Unusual echocardiographic features seen in a case of giant cell myocarditis

The case of an 18-year-old college football player with a recent history of streptococcal pharyngitis who was experiencing progressive disabling dyspnea on exertion with easy fatigability and lack of stamina, and was taken to the hospital after a syncopal episode is described. The patient was initially diagnosed with heart failure and treated accordingly. However, because of a fulminant clinical deterioration, an endomyocardial biopsy was recommended, which showed focal giant cell transformation consistent with giant cell myocarditis. Treatment with methylprednisolone and cyclosporine was promptly initiated. Several apical clots were noted during treatment, but the patient attained full recovery with treatment.

Rhythm control versus rate control for atrial fibrillation and heart failure

BACKGROUND

It is common practice to restore and maintain sinus rhythm in patients with atrial fibrillation and heart failure. This approach is based in part on data indicating that atrial fibrillation is a predictor of death in patients with heart failure and suggesting that the suppression of atrial fibrillation may favorably affect the outcome. However, the benefits and risks of this approach have not been adequately studied.

METHODS

We conducted a multicenter, randomized trial comparing the maintenance of sinus rhythm (rhythm control) with control of the ventricular rate (rate control) in patients with a left ventricular ejection fraction of 35% or less, symptoms of congestive heart failure, and a history of atrial fibrillation. The primary outcome was the time to death from cardiovascular causes.

RESULTS

A total of 1376 patients were enrolled (682 in the rhythm-control group and 694 in the rate-control group) and were followed for a mean of 37 months. Of these patients, 182 (27%) in the rhythm-control group died from cardiovascular causes, as compared with 175 (25%) in the rate-control group (hazard ratio in the rhythm-control group, 1.06; 95% confidence interval, 0.86 to 1.30; P=0.59 by the log-rank test). Secondary outcomes were similar in the two groups, including death from any cause (32% in the rhythm-control group and 33% in the rate-control group), stroke (3% and 4%, respectively), worsening heart failure (28% and 31%), and the composite of death from cardiovascular causes, stroke, or worsening heart failure (43% and 46%). There were also no significant differences favoring either strategy in any predefined subgroup.

CONCLUSIONS

In patients with atrial fibrillation and congestive heart failure, a routine strategy of rhythm control does not reduce the rate of death from cardiovascular causes, as compared with a rate-control strategy. (ClinicalTrials.gov number, NCT00597077.)

A randomized trial comparing effects of radiofrequency and cryoablation on the structural integrity of esophageal tissue

BACKGROUND

Esophageal injury is a rare, but catastrophic complication of radiofrequency (RF) pulmonary vein isolation. It is not known if cryoablation is less likely to injure esophageal tissue. The purpose of this study is to compare the effects of RF and cryoablation on the structural integrity of esophageal tissue.

METHODS AND RESULTS

Porcine esophageal tissue was sectioned into 396 strips measuring 3 mm in width by 30 mm in length. Samples were randomly assigned to receive no ablation (149 specimens in the control group), RF ablation (126 specimens) or cryoablation (121 specimens). A single ablation was administered in the center of the tissue sample. A force gauge was used to measure the tensile strength of the tissue sample in Newtons. Groups were compared using ANOVA and a Bonferroni post-test. The mean tensile strength in the control group was 2.19 N (SD, 2.17), 1.66 N (SD, 0.88) for RF ablated tissue and 1.96 N (SD, 1.68) for cryo. RF ablation resulted in a significant reduction in esophageal tensile strength when compared to control (t = 2.59), however cryo did not (t = 1.11). On microscopic evaluation RF ablation disrupted elastic fiber architecture whereas cryoablation did not.

CONCLUSIONS

Cryoablation has no significant adverse impact on the structural integrity of esophageal tissue. Cryoablation may be a safer alternative to RF for left atrial ablation and reduce the risk of esophageal injury and atrial-esophageal fistula formation.

Atrial overdrive pacing and incidence of heart failure-related adverse events in permanently paced patients

BACKGROUND

Atrial overdrive pacing algorithms may be effective in preventing or suppressing atrial fibrillation (AF). However, the maintenance of a heart rate incessantly faster than spontaneous could induce left ventricular (LV) dysfunction and promote heart failure (HF) on the long term.

OBJECTIVE

This post hoc analysis examined the effects of a new overdrive algorithm on the incidence of HF-related adverse events in 411 patients enrolled in the ADOPT-A trial.

MATERIALS AND METHODS

The AF Suppression algorithm was randomly programmed ON in 209 patients (treatment group) versus OFF in 202 patients (control group). The incidence of HF-related adverse events and HF-related deaths over a 6-month follow-up was compared between the two groups. Patients with versus without HF-related clinical events were also compared to each other within each group.

RESULTS

There were eight HF-related adverse clinical events (3.8%) in the treatment group and 11 (5.4%) in the control group, including four HF-related deaths (1.9 vs. 2.0%) in each group during follow-up. Baseline NYHA functional class in patients with versus without HF-related adverse events was 1.4 +/- 0.5 versus 1.5 +/- 0.7 in the control, and 1.5 +/- 0.8 versus 1.5 +/- 0.6 in the treatment group. LV ejection fraction (EF) was 49 +/- 7% in patients with, versus 57 +/- 12% in patients without HF-related adverse events, in the control group, and 43 +/- 14% in patients with, versus 56 +/- 13% in patients without HF-related adverse events, in the treatment group. LVEF was lowest and similar in both groups among patients who died from HF (35 +/- 10% in the control and 38 +/- 27% in the treatment group).

CONCLUSIONS

In ADOPT-A, HF-related clinical events and deaths were related to LV dysfunction and not to atrial pacing overdriven by the AF suppression algorithm.

Prediction of atrial fibrillation in patients with cardiac dysfunctions†

AIMS

Atrial fibrillation (AF) is a common arrhythmia in advanced heart failure. The occurrence of AF increases the risk of death and hospitalization for patients with heart failure. The results of different studies indicated that patients with paroxysmal AF have a longer filtered P wave duration (FPD), a lower root mean square voltage of the last 20 ms of the P wave (RMS 20), and a lower chemoreflexsensitivity (CHRS). Our study bases on these observations in order to examine the methods for predicting AF in patients with a left ventricular ejection fraction below 40% without a prior documentation of AF.

METHODS AND RESULTS

The ratio between the difference of RR intervals in ECG and venous pO(2) before and after 5-min oxygen inhalation was measured (ms/mmHg) in order to determine the CHRS. A P wave signal-averaged ECG was performed for the measurement of FPD and RMS 20. The measurements were only performed in 94 patients with sinus rhythm. AF occurred during the mean follow-up of 39.9 months in 24 patients (26%). There were no significant differences concerning age, heart diseases, sex, ejection fraction, heart rate, or the use of drugs. The FPD (130.3 +/- 4.2 vs. 118.9 +/- 12.4 ms, P < 0.0001) was significantly longer and the RMS 20 (3.03 +/- 0.95 vs. 3.83 +/- 1.58 microV, P = 0.02) was significantly lower in patients with AF than in sinus rhythm. The CHRS did not differ significantly between both groups (3.57 +/- 1.49 vs. 3.48 +/- 1.62 ms/mmHg, P = 0.81). The chi(2) test showed that the threshold of FPD>or=125 ms and RMS 20 <or=3.3 microV revealed the best predictive value for AF. A stepwise logistic regression analysis of all variables identified the threshold of FPD>or=125 ms and RMS 20 <or=3.3 microV (OR 18.71; 95% CI, 4.85-72.16, P < 0.0001) as independent predictors for AF.

CONCLUSIONS

In summary, our data show that the results of a P wave signal-averaged ECG can predict the risk for new onset of AF in patients with heart failure. The value of signal-averaged FPD is probably the result of reflecting the intra-atrial conduction delay, which is a pathophysiological condition for AF. The CHRS is not a suitable method for predicting AF.

The management of atrial fibrillation in heart failure

The development of atrial fibrillation (AF) can greatly complicate the course of heart failure (HF). Although recent trials have indicated the nonsuperiority of a rhythm control strategy in the general population with AF, this may not apply to patients with HF. We feel strongly that AF be treated aggressively in patients with HF, defaulting toward an initial rhythm control strategy, to avoid the hemodynamic detriment of irregular rapid ventricular response and the development of tachycardia-related myopathy. The index episode is treated with cardioversion and antiarrhythmic therapy. If significant benefit is demonstrated, the rhythm control strategy is maintained, to the point of catheter ablation for AF if necessary. If there is no change in cardiac performance or symptoms after cardioversion, strict rate control is enforced, to the point of atrioventricular node ablation and pacing if necessary.

Extensive Ablation During Pulmonary Vein Antrum Isolation Has No Adverse Impact on Left Atrial Function: An Echocardiography and Cine Computed Tomography Analysis

BACKGROUND

Although pulmonary vein antrum isolation (PVAI) may cure atrial fibrillation (AF) and improve left atrial (LA) function, the effect of extensive LA ablation on LA function is not well known.

OBJECTIVE

To assess the impact of PVAI on LA function remotely postablation.

METHODS

Consecutive patients undergoing PVAI had either transthoracic (TTE) and transesophageal (TEE) echocardiography (n = 41) or cine EBCT (n = 26) performed preablation and 6 months postablation. Only patients with paroxysmal and persistent, but not permanent, AF were included. Imaging was done in sinus rhythm for all patients. LA diameter (LAD), LA systolic and diastolic areas, and left atrial fractional area change (LFAC) were assessed by TTE. Transmitral (TMF), left atrial appendage (LAA), and pulmonary venous (PVF) Doppler flows were measured by TEE. Peak A on TMF, LAA peak emptying velocity (LAAF), and peak A reversal (AR) on PVF were used as surrogates of LA contractile function. Peak S on PV flow was used as a surrogate of reservoir function. LA areas, volumes, and LA ejection fraction (LAEF) were measured from cine EBCT.

RESULTS

Mean radiofrequency ablation time was 45 +/- 21 minutes. All four PVs were isolated for all patients; there were no cases of PV stenosis. Echocardiography revealed a significant reduction in LAD and LA areas post-PVAI. Both peak A and peak AR were also higher post, while other variables showed strong trends toward improvement. In the subset of patients with persistent AF, post-PVAI improvements were seen in LA size, peak A, and even peak S (P = 0.04). Cine EBCT showed a significant decrease in both LA areas and volumes post-PVAI. There was also a significant improvement in LAEF post-PVAI from 17 +/- 6% to 22 +/- 5% (P = 0.01).

CONCLUSION

Extensive ablation during PVAI does not cause deterioration in LA function, and may cause long-term improvement, especially in patients with higher AF burden.

Errors and pitfalls in the non-invasive management of atrial fibrillation

Atrial fibrillation (AF) is the most common arrhythmia encountered in clinical practice while it has a significant impact on morbidity and mortality. The errors and pitfalls in the management of AF patients are not uncommon. These include errors in detection and management of the underlying conditions that promote and perpetuate the arrhythmia, in the selection and monitoring of antithrombotic treatment, in the selection of appropriate strategy for arrhythmia management (rate or rhythm control), in the cardioversion procedure, in the prevention of recurrence after cardioversion, in the acute or chronic control of heart rate, and in the monitoring of drug toxicities. The heterogeneity of the disease along with the diversity of current treatment options mainly account for these problems. Nevertheless, deep knowledge of the evidence-based therapeutic approaches, as well as the development of individualized therapeutic strategies, can substantially improve the effective management of such patients.

Antiadrenergic therapy in the control of atrial fibrillation

Atrial fibrillation (AF) in heart failure develops commonly in older individuals and its prevalence increases as heart failure severity progresses. Because of deteriorating hemodynamics, patients with heart failure are at increased risk for developing AF and, conversely, AF in heart failure patients is associated with adverse hemodynamic changes. AF is believed to increase the mortality risk in heart failure, which may be minimized by treatment that includes the control of ventricular rate, prevention of thrombotic events, and conversion to normal sinus rhythm. Clinical guidelines recommend amiodarone or dofetilide in heart failure patients, but these drugs have certain drawbacks, such as an increased risk for bradyarrhythmias with amiodarone and proarrhythmic reaction with dofetilide. Some but not all clinical trials have suggested that rate control should be the primary therapeutic goal in high-risk heart failure patients with AF and, if unsuccessful, followed by rhythm control. The former is effectively achieved with rate-lowering beta-blockers alone or in combination with digoxin. Recent studies evaluating the effects of combination carvedilol/digoxin therapy demonstrate synergistic effects between the two drugs. This combination therapy decreased heart failure symptoms, effectively reduced ventricular rate, and improved ventricular function to a greater extent compared with that produced by either drug alone. Although digoxin alone is an effective heart failure treatment, its use as a single rate-control therapy is often ineffective in heart failure patients with AF associated with rapid ventricular response. Carvedilol is effective, alone or in combination, with digoxin in such heart failure patients with AF, and has been shown to reduce mortality risk in patients with chronic heart failure during prolonged therapy.

Conduction Recovery After Pulmonary Vein Isolation for Atrial Fibrillation

BACKGROUND

Although pulmonary vein (PV) isolation is useful for curing atrial fibrillation (AF), its recurrence rate is still high, so the aim of the present study was to investigate the cause of recurrence after PV isolation.

METHODS AND RESULTS

Eighty-five patients with paroxysmal AF underwent PV isolation and AF recurred in 48 patients after the first session. Thirty of these 48 patients who underwent a second session were evaluated. In 49 (71%) of 69 PVs ablated in 25 patients (83%), recovery of conduction was observed between the left atrium and PV. In 45 (92%) of 49 PVs, conduction recurrences were seen from the same segment or part of a segment that was ablated in the first session. However, in the other 4 PVs (8%), conduction recurrences occurred in a different segment that had not been ablated before. In the second session, the mean number of segments ablated in the PV ostium was significantly less than in the first session (2.3+/-5.0 vs 1.4+/-6.0, p<0.01). After the second session, 16 patients (53%) did not show recurrence of AF.

CONCLUSION

The major cause of recurrence of PV isolation was recovery of PV conduction from the same segment that had been ablated in the PV ostium. Therefore, an additional session may be necessary to increase the success rate.

Treatment of arrhythmias in patients with congestive heart failure

Both ventricular and atrial arrhythmias are commonly encountered in patients with ventricular dysfunction. In fact, roughly half of the deaths occurring in patients with ventricular dysfunction are caused by ventricular arrhythmias. Atrial arrhythmias in this patient population compromise left ventricular filling and if uncontrolled can exacerbate (and in some cases cause) the underlying myopathic process. Consequently, the diagnosis and treatment of these complex, and often life-threatening, arrhythmias is a critical component in the management of congestive heart failure (CHF). As the complexity of pharmacologic and nonpharmacologic antiarrhythmic therapy evolves, it has become increasingly important to understand the potential benefits and limitations of the various treatment modalities in the setting of patients with CHF. The management of arrhythmias in patients with CHF includes conventional drug therapies, as well as therapies directed specifically at treating the arrhythmias that are encountered. The treatment of atrial arrhythmias may include anticoagulation, drugs for rate control, rhythm control, or radiofrequency ablation. The treatment of ventricular arrhythmias, conversely, uses the implantable cardioverter-defibrillator to prevent sudden death, with adjuvant drug therapy or ablation for refractory ventricular tachycardia. This article provides an overview of the current state-of-the-art arrhythmia management in patients with CHF.