Catheter Ablation for Atrial Fibrillation in Structural Heart Disease: A Review

Atrial fibrillation (AF) is the most common arrhythmia encountered in clinical practice. Patients with structural heart disease (SHD) are at an increased risk of developing this arrhythmia and are particularly susceptible to the deleterious hemodynamic effects it carries. In the last two decades, catheter ablation (CA) has emerged as a valuable strategy for rhythm control and is currently part of the standard care for symptomatic relief in patients with AF. Growing evidence suggests that CA of AF may have potential benefits that extend beyond symptoms. In this review, we summarize the current knowledge of this intervention on SHD patients.

Development and Validation of a Nomogram for Estimation of Left Atrial Thrombus or Spontaneous Echo Contrast Risk in Non-Valvular Atrial Fibrillation Patients with Low to Borderline CHA2DS2-VASc Score

Purpose

Left atrial thrombus (LAT)/left atrial spontaneous echo contrast (LASEC) still exists in CHA₂DS₂-VASc score-defined low/borderline risk population. The purpose of this study is to explore the risk factors that associate with LAT/SEC and to create a nomogram to predict LAT/SEC risk in NVAF patients with low/borderline CHA₂DS₂-VASc scores.

Patients and Methods

A total of 834 NVAF patients with complete data on transesophageal echocardiography (TEE) were included in this study. Univariate and multivariate logistic regression analyses were performed to identify the risk factors that associate with LAT/SEC, and a nomogram was established based on the results. Receiver operating characteristic curve (ROC), calibration curve and decision curve analysis were performed to verify the predictive power of nomogram.

Results

The rates for LAT/SEC for the training and validation cohorts were 84 (14.7%) and 30 (11.4%), respectively. Independent factors including age, left ventricular ejection fraction (LVEF), left atrial diameter (LAD), smoke, non-paroxysmal AF (NPAF), and E/e’ were considered to construct the nomogram for LAT/SEC. The AUC for nomogram was 0.839 and 0.811 in the training and validation cohorts, respectively. The calibration and decision curve analysis showed that the nomogram had a good prediction capacity and would be clinically useful.

Conclusion

Age, LVEF, LAD, smoke, NPAF, and E/e’ are independently associated with LAT/SEC in NVAF patients with low/borderline CHA₂DS₂-VASc scores. The nomogram that incorporates these six variables effectively predict LAT/SEC risk in NVAF patients with low/borderline CHA₂DS₂-VASc scores.

Echocardiographic diagnosis of atrial cardiomyopathy allows outcome prediction following pulmonary vein isolation

BACKGROUND

Relevant atrial cardiomyopathy (ACM), defined as a left atrial (LA) low-voltage area ≥ 2 cm2 at 0.5 mV threshold on endocardial contact mapping, is associated with new-onset atrial fibrillation (AF), higher arrhythmia recurrence rates after pulmonary vein isolation (PVI), and an increased risk of stroke. The current study aimed to assess two non-invasive echocardiographic parameters, LA emptying fraction (EF) and LA longitudinal strain (LAS, during reservoir (LASr), conduit (LAScd) and contraction phase (LASct)) for the diagnosis of ACM and prediction of arrhythmia outcome after PVI.

METHODS

We prospectively enrolled 60 consecutive, ablation-naive patients (age 66 ± 9 years, 80% males) with persistent AF. In 30 patients (derivation cohort), LA-EF and LAS cut-off values for the presence of relevant ACM (high-density endocardial contact mapping in sinus rhythm prior to PVI at 3000 ± 1249 sites) were established in sinus rhythm and tested in a validation cohort (n = 30). Arrhythmia recurrence within 12 months was documented using 72-h Holter electrocardiograms.

RESULTS

An LA-EF of < 34% predicted ACM with an area under the curve (AUC) of 0.846 (sensitivity 69.2%, specificity 76.5%) similar to a LASr < 23.5% (AUC 0.878, sensitivity 92.3%, specificity 82.4%). In the validation cohort, these cut-offs established the correct diagnosis of ACM in 76% of patients (positive predictive values 87%/93% and negative predictive values 73%/75%, respectively). Arrhythmia recurrence in the entire cohort was significantly more frequent in patients with LA-EF < 34% and LASr < 23.5% (56% vs. 29% and 55% vs. 26%, both p < 0.05).

CONCLUSION

The echocardiographic parameters LA-EF and LAS allow accurate, non-invasive diagnosis of ACM and prediction of arrhythmia recurrence after PVI.

Left Ventricular Diastolic Dysfunction Is Associated With the Prevalence of Paroxysmal Atrial Fibrillation Determined on the Latest Echocardiographic Criteria

Background: The relationship between left ventricular diastolic dysfunction (LVDD) and paroxysmal atrial fibrillation (PAF) remains unclear because of a lack of standard measures to evaluate LVDD. Accordingly, we examined the association between the prevalence of PAF and each LVDD grade determined according to the latest American Society of Echocardiography guidelines.

Methods and Results: In all, 2,063 patients without persistent AF who underwent echocardiography at Saitama Municipal Hospital from July 2016 to June 2017 were included in the study. Patients were divided into LVDD 6 categories: No-LVDD (n=1,107), Borderline (n=392), Grade 1 (n=204), Indeterminate (n=62), Grade 2 (n=254), and Grade 3 (n=44). PAF was documented in 111 (10.0%), 81 (20.7%), 28 (13.7%), 6 (9.7%), 52 (20.5%), and 24 (54.5%) patients in the No-LVDD, Borderline, Grade 1, Indeterminate, Grade 2, and Grade 3 categories, respectively. PAF prevalence was higher in patients with Grade 3 LVDD across the whole study population. Subgroup analyses showed that the prevalence of PAF increased with increased LVDD grade in patients with reduced left ventricular ejection fraction. This relationship was significant in multivariate analysis including various patient characteristics.

Conclusions: LVDD severity determined on the basis of the latest echocardiographic criteria was associated with the prevalence of PAF. The present findings shed light on the development of new therapeutic markers for PAF.

Echocardiographic predictors of atrial fibrillation recurrence after catheter ablation: A literature review

BACKGROUND

Catheter ablation (CA) is a well-known treatment option for patients with symptomatic drug-resistant atrial fibrillation (AF). Multiple factors have been identified to determine AF recurrence after CA, however their predictive value is rather small. Identification of novel predictors of CA outcome is therefore of primary importance to reduce health costs and improve long-term results of intervention. The recurrence of AF following CA is related to severity of left ventricular (LV) dysfunction, extent of atrial dilatation and fibrosis. The aim of this paper was to present and discuss the latest studies on the utility of echocardiographic parameters in terms of CA effectiveness in patients with paroxysmal and persistent AF.

METHODS

PubMed, Google Scholar, EBSCO databases were searched for studies reporting echocardiographic preprocedural predictors of AF recurrence after CA. LV systolic and diastolic function, as well as atrial size, strain and dyssynchrony were taken into consideration.

RESULTS

Twenty one full-text articles were analyzed, including three meta-analyses. Several echocardiographic parameters have been reported to determine a risk of AF recurrence after CA. There are conventional methods that measure left atrial size and volume, LV ejection fraction, parameters assessing LV diastolic dysfunction, and methods using more innovative technologies based on speckle tracking echocardiography to determine left atrial synchrony and strain. Each of these parameters has its own predictive value.

CONCLUSIONS

Regarding CA effectiveness, every patient has to be evaluated individually to estimate the risk of AF recurrence, optimally using a combination of several echocardiographic parameters.

Asymmetrical left atrial remodelling in atrial fibrillation: relation with diastolic dysfunction and long-term ablation outcomes

Aims

The association between anatomical left atrial (LA) remodelling and ventricular diastolic dysfunction (DD) in atrial fibrillation (AF) patients is not well studied. We aimed to examine the effect of DD on anatomic LA remodelling and their relation with ablation outcomes.

Methods and results

In 104 patients (58 ± 10 years, 69% male) referred for AF ablation, LA volume (LAV) was determined by computed tomography. A cutting plane, between the pulmonary vein (PV) ostia and the appendage and parallel to the posterior wall, divided LAV into anterior- (LA-A) and posterior-LA parts. The ratio of LA-A and LAV was defined as the LA asymmetry index (ASI). According to the current guidelines, the presence of DD was evaluated by echocardiography. Regression analysis was used to identify predictors of asymmetry changes and long-term success. Univariate linear regression revealed that ASI is associated with LAV, the presence of DD, and mitral regurgitation. Asymmetry index was higher in patients with DD (n = 35, 62 ± 5 vs. 59 ± 6%, P = 0.013) or mitral regurgitation (n = 67, 61 ± 6 vs. 58 ± 5%, P = 0.025). Multiple linear regression analysis showed that DD (B = 2.6, β = 0.207, 95% confidence interval, CI: 0.167-5.011, P = 0.036) and LAV (B = 0.037, β = 0.211, 95% CI: 0.003-0.071, P = 0.033) were the only factors independently associated with ASI (adjusted r2 = 0.92, F = 6.2, P = 0.003). Regression analysis showed that AF recurrence (33% after 24 months) is associated with asymmetric LA changes, while DD is not.

Conclusions

Left atrial symmetry changes are associated with DD and dilatation. Since DD could cause LA remodelling, appropriate early treatment should be considered for AF patients with DD, before geometrical changes occur.

Are left ventricular ejection fraction and left atrial diameter related to atrial fibrillation recurrence after catheter ablation?: A meta-analysis

Atrial fibrillation (AF), the most common form of arrhythmia, is associated with the prevalence of many common cardiovascular and cerebrovascular diseases. Catheter ablation is considered the first-line therapy for AF; however, AF recurrence is very common after catheter ablation. Studies have been performed to analyze the factors associated with AF recurrence, but none have reached a consistent conclusion on whether left ventricular ejection fraction (LVEF) and left atrial diameter (LA diameter) affect AF recurrence after catheter ablation.The databases PubMed, Embase, and the Cochrane Library were used to search for relevant studies up to September 2017. RevMan 5.3.5 software provided by the Cochrane Collaboration Network was used to conduct this meta-analysis.Thirteen studies involving 2825 patients were included in this meta-analysis. Overall, the results revealed that elevated LA diameter values were significantly associated with AF recurrence in patients after catheter ablation (MD = 2.19, 95% CI: 1.63-2.75, P < .001), while baseline LVEF levels were not significantly positively associated with AF recurrence in patients after catheter ablation (MD = -0.91, 95% CI: -1.18 to 1.67, P = .14).Overall, elevated LA diameter may be associated with AF recurrence after catheter ablation; however, there was no direct relationship between LVEF values and AF recurrence after catheter ablation when baseline LVEF values are normal or mildly decreased. Besides, because of publication bias, further studies should be performed to explore the mechanisms underlying AF recurrence.

Use of acoustic cardiography immediately following electrical cardioversion to predict relapse of atrial fibrillation

Predicting atrial fibrillation (AF) recurrence after successful electrical cardioversion (ECV) is difficult. The main aim of this study was to investigate whether acoustic cardiography (AUDICOR® 200) immediately post-ECV might provide indices for AF relapse following cardioversion. Acoustic cardiography parameters included Electromechanical Activation Time (EMAT), Left Ventricular Systolic Time (LVST), QRS duration, heart rate and third heart sound intensity (S3 Strength). We analysed data from 140 patients who underwent successful cardioversion and in whom AUDICOR results and echocardiographic measurements immediately after (baseline) ECV were available. Patients were prospectively followed-up at 4-6 weeks, 3 and 12 months post-ECV, and sinus rhythm maintenance was evaluated using acoustic cardiography and Holter electrocardiography. The effect of each baseline AUDICOR parameter on the hazard of AF relapse was investigated using Cox proportional hazards (PH) models. Fifty patients (35.7%) had AF relapse. Of all the AUDICOR parameters, only S3 Strength exhibited consistent predictive value. Increasing S3 Strength increased the hazard of relapse in a univariable Cox PH model (HR=2.52, p=0.003), and in two multivariable Cox PH model constructions (Model 1 excluded heart rate and Model II excluded EMAT/RR, LVST and LVST/RR) both of which included the parameters as continuous variables (Model I: HR=1.15, p=0.042; Model II: HR=1.14, p=0.045) or the parameters dichotomized according to suggested cut-points (Model I: HR=2.5, p=0.007; Model II: HR=2.09, p=0.031). In conclusion, this study suggests that acoustic cardiography may be a simple inexpensive and quantitative bedside method to assist in prediction of AF recurrence after ECV.

Relationship between left ventricular diastolic dysfunction and very late recurrences after multiple procedures for atrial fibrillation ablation

Although very late recurrences (VLRs) (first recurrence >12 months after the last catheter ablation) of atrial fibrillation (AF) after multiple catheter ablation procedures are rare, it remains a critical issue. The risk factors for VLRs remain largely unclear. From December 2011 to April 2014, 253 patients underwent an initial catheter ablation. Of the 253 patients, 21 had AF recurrences within 1 year after the last catheter ablation. The study was conducted in the remaining 232 patients. Left ventricular diastolic dysfunction (LVDD) was assessed by echocardiography using composite categories with tissue Doppler imaging and left atrial volume measurements, i.e., a septal e' < 8 cm/s, lateral e' < 10 cm/s, and left atrium volume index (LAV/body surface area) (LAVI) ≥34 mL/m². LVDD was observed in 40 patients. Sinus rhythm was preserved in 220 patients after multiple catheter procedures, and 12 had VLRs. The clinical factors possibly related to VLRs were examined, and a multivariate regression analysis showed that LVDD was the only independent risk factor for VLRs (hazard ratio: 10.31, 95% confidence interval: 2.78-38.18, P < 0.0001). LVDD at baseline is a risk factor for a VLR after multiple catheter ablation procedures for AF.

Prognostic implication of left atrial sphericity in atrial fibrillation patients undergoing radiofrequency catheter ablation

BACKGROUND

Left atrial (LA) sphericity can predict recurrence of atrial fibrillation (AF) after radiofrequency catheter ablation (RFCA). We sought to reconfirm the prognostic role of atrial sphericity after RFCA of atrial fibrillation (AF), assess any relationship between the atrial pressure and sphericity, and determine the characteristics of the patients for whom atrial sphericity was most highly predictive.

METHODS

All 148 nonvalvular AF patients (57 ± 11 years, 121 men, 95 paroxysmal AF [PaAF]) who underwent RFCA were enrolled. The LA volume (LAV) was determined and LA sphericity assessed from three-dimensional computed tomographic images. The preprocedural mean LA pressure (mLAP) was measured.

RESULTS

After a 3-month blanking period, AF/atrial tachycardia (AT) recurrences within 1 year were documented in 38 patients (26%). Patients with recurrence had a greater LAV (124 ± 35 mL vs 151 ± 45 mL, P < 0.001) and LA sphericity (0.669 ± 0.040 vs 0.684 ± 0.038, P = 0.041). In patients with smaller LAs (LAV < 125 mL), LA sphericity predicted AF/AT recurrences (odds ratio [OR]: 1.030 [for each 0.001 increase], 95% confidence interval [CI]: 1.008-1.053, P = 0.007), whereas the LAV did not. In patients with larger LAs (LAV ≥ 125 mL), the LAV could predict recurrence (OR: 1.021, 95% CI: 1.001-1.041, P = 0.036), while the LA sphericity could not. The LA sphericity and mLAP are linearly correlated (r = 0.345, P < 0.022) in persistent AF, but not PaAF.

CONCLUSIONS

LA spherical change precedes severe LA enlargement in AF. It predicts 1-year AF/AT recurrence after RFCA and is more important than the LA size in patients with less severe LA enlargement.

Conventional versus 3-D Echocardiography to Predict Arrhythmia Recurrence After Atrial Fibrillation Ablation

BACKGROUND

Arrhythmia recurrence after atrial fibrillation (AF) ablation remains high and requires repeat interventions in a substantial number of patients. We assessed the value of conventional and 3-D echocardiography to predict AF recurrence.

METHODS AND RESULTS

Consecutive patients undergoing AF ablation by means of pulmonary vein isolation were included in a prospective registry. Echocardiograms were obtained prior to the ablation procedure, and analyzed offline in a standardized manner, including 3-D left atrial (LA) volumetry and determination of LA function and sphericity. The primary endpoint, AF recurrence (>30 seconds) between 3 to 12 months after AF ablation, was independently adjudicated. We included 276 patients (73% male, mean age 59.9 ± 9.9 years). Paroxysmal and persistent AF were present in 178 (64%) and 98 (36%) patients, respectively. Mean left ventricular ejection fraction and indexed LA volume in 3-D (LAVI) were 52 ± 12% and 42 ± 13 mL/m² , respectively. AF recurrence was observed in 110 (40%) patients after a single procedure. Median (interquartile range) time to AF recurrence was 123 (92; 236) days. In multivariable Cox regression models, the only predictors for AF recurrence were the minimal, maximal, and indexed 3-D LA volumes, P = 0.024, P = 0.016, and P = 0.014, respectively. Quartile specific analysis of 3-D LAVI showed an HR of 1.885 (95%CI 1.066-3.334; P for trend = 0.015) for the highest compared to the lowest quartile.

CONCLUSION

Our results show the important role of LA volume for the long-term freedom from arrhythmia after AF ablation. These data also highlight the potential of 3-D echocardiography in this context and may facilitate patient selection for AF ablation.

Assessment of atrial conduction times in patients with mild diastolic dysfunction and normal atrial size

Objective:

Abnormalities in atrial electromechanical delays (EMDs) are considered independent predictors of atrial fibrillation and can reflect atrial remodeling. The main purpose in this study was to compare inter-left and right intra-atrial EMDs of patients with mild left ventricular (LV) diastolic dysfunction, without left atrial (LA) structural remodeling in the absence of high filling pressure, with healthy individuals.

Methods:

In this prospective study, a total of 41 consecutive outpatients who were referred to our echocardiography laboratory with mild diastolic dysfunction (age: 60.9±9.6 years) and 45 healthy control subjects who were referred from an outpatient clinic for check-up (age: 32.2±10.3 years) with normal diastolic function were enrolled into this study. All subjects had normal LA volume and normal right atrial area and did not have high filling pressure. Diastolic dysfunction were determined per American Society of Echocardiography recommendations; so, the following indices were measured: peak early (E) and atrial (A) flow velocities (cm/s), E/A ratio, and deceleration time (DT) (ms) of mitral inflow, systolic (S) and diastolic (D) pulmonary vein wave velocities (cm/s) by pulse wave Doppler, and e’ in septal and lateral mitral annulus by pulse wave tissue Doppler. Time interval from the onset of P wave on the ECG to the beginning of the late diastolic wave (Am wave) on tissue Doppler trace, which is named PA, was obtained from the lateral and septal mitral annulus and right ventricular (RV) tricuspid annulus as atrial conduction times (ACTs) and were named lateral PA, septal PA, and RV PA, respectively. The difference between lateral PA and septal, PA septal and RV PA was defined as left and right intra-atrial EMD, respectively. The difference between lateral PA and RV PA was defined as inter-atrial EMD. Data analysis was done by independent student’s t-test, Mann-Whitney U test, χ² test, Spearman rank order, Pearson’s correlation coefficient, and multivariate regression analysis in the appropriate site.

Results:

A, DT, S/D ratio, and E/e’ (average) were significantly lower in the control group, and E, D, E/A ratio, e’ septal, and e’ lateral wall were significantly lower in the patient group. Atrial conduction times were longer in the patient group, but in the multivariate analysis, there was no correlation between ACTs and diastolic dysfunction. There was no significant difference in left intra-atrial EMD (14.2±9.7 ms vs. 16.4±11.4 ms; p=0.336), right intra-atrial EMD (12.8±12.2 ms vs. 15.4±12.1 ms; p=0.321), and inter-atrial EMD (26.9±13.7 ms vs. 31.7±13.7 ms; p=0.108) between the two groups. Multivariate analysis showed no correlation between inter- and intra-atrial EMDs and diastolic dysfunction.

Conclusion:

There was no significant difference in ACTs and inter-atrial and left and right intra-atrial EMD in patients with mild LV diastolic dysfunction and normal LA volume in the absence high filling pressure compared with normal subjects.

The ratio of early transmitral flow velocity (E) to early mitral annular velocity (Em) predicts improvement in left ventricular systolic and diastolic function 1 year after catheter ablation for atrial fibrillation

AIMS

Successful rhythm control after atrial fibrillation catheter ablation is known to induce left atrial reverse remodelling and improve left ventricular (LV) function. We explored the clinical factors affecting LV systolic and diastolic function 1-year after catheter ablation for atrial fibrillation.

METHODS AND RESULTS

We compared pre-procedural and 1-year follow-up echocardiograms in 521 patients with atrial fibrillation who underwent catheter ablation. Left ventricular systolic function was estimated by the ejection fraction (EF); diastolic function was estimated by the ratio of early transmitral flow velocity (E) to early mitral annular velocity (Em). (i) Catheter ablation of atrial fibrillation significantly reduced left atrium volume index (P < 0.001) and improved LV EF both in patients with recurrent atrial fibrillation (n = 133, P = 0.008) and those without recurrence (n = 388, P < 0.001). (ii) Follow-up EF was significantly improved in patients with baseline E/Em < 15 (n = 454, P < 0.001), whereas E/Em was significantly reduced in patients with pre-procedural E/Em ≥ 15 (n = 67, P = 0.008). (iii) Baseline E/Em < 15 (β = -3.854, 95% CI -5.99 to -1.72, P < 0.001), baseline EF <50% (β = 10.586, 95% CI 7.55 to 13.63, P < 0.001), and female (β = -1.726, 95% CI -3.36 to -0.10, P = 0.038) were independently associated with improved EF. Baseline E/Em ≥ 15 (β = 4.896, 95% CI 3.45 to 6.34, P < 0.001) and younger age (β = -0.066, 95% CI -0.11 to -0.02, P = 0.003) were independent factors associated with improved E/Em.

CONCLUSION

Pre-procedural E/Em predicted improvement in LV systolic and diastolic functions 1 year after catheter ablation for atrial fibrillation. Low baseline E/Em was independently associated with improved EF, while high E/Em predicted improvement in LV diastolic function.

Impact of left ventricular diastolic dysfunction on outcome of catheter ablation for atrial fibrillation in patients with hypertrophic cardiomyopathy

BACKGROUND

The relationship between outcome of radiofrequency catheter ablation (RFCA) for atrial fibrillation (AF) and the severity of left ventricular (LV) diastolic dysfunction in patients with hypertrophic cardiomyopathy (HCM) remains unknown.

METHODS AND RESULTS

Twenty-two HCM patients (12 female, aged 65 ± 11 years) with paroxysmal (n=5; 23%) or persistent (n=17; 77%) AF were enrolled. LV diastolic function was evaluated according to the ratio of the mitral inflow early filling velocity to the velocity of the early medial mitral annular ascent (E/e') measured on pulsed wave and tissue Doppler assessments in all patients. Pulmonary vein isolation was performed in all patients. A second procedure was performed in 3 patients. During a follow-up of 21 ± 12 months, sinus rhythm was maintained in 13 of 22 patients (59%). E/e' was significantly higher in the patients with AF recurrence than in those without (18 ± 7 vs. 11 ± 3; P<0.01). On Kaplan-Meier analysis the prevalence of AF recurrence was significantly higher in patients with E/e' ≥ 15 (n=6) than in those with E/e' <15 (n=16; P<0.01). On multivariate Cox regression analysis the only significant and independent predictor for AF recurrence was E/e' (hazard ratio, 1.16; 95% confidence interval: 1.01-1.37, P=0.03).

CONCLUSIONS

LV diastolic dysfunction evaluated using E/e' was associated with difficulty of rhythm control after RFCA in patients with HCM and AF.

Selection for atrial fibrillation ablation: Importance of diastolic function grading

BACKGROUND

Pulmonary vein isolation (PVI) has become an accepted therapy for patients with atrial fibrillation (AF) and the indications have widened to include non-paroxysmal AF-patients. Maintenance of sinus rhythm after PVI can be adversely affected by clinical or echocardiographic parameters, which should be clearly identified.

METHODS AND RESULTS

After baseline clinical and echocardiographic evaluations, PVI was performed in patients with paroxysmal or non-paroxysmal AF. The follow-up strategy after PVI included: (1) clinical follow up, 12-lead electrocardiography (ECG) and 24-h ECG every 3 months, (2) trans-telephonic ECGs twice daily and when symptomatic (over 4 weeks) every 3 months, or (3) continuous monitoring via implanted devices. A recurrence was an atrial arrhythmia lasting >30s. All 340 PVI procedures of 229 patients were analyzed. On average, 1.5 PVI procedures per patient (range, 1-6 PVI) were performed. The mean age was 58±11 years (73% male) with 109 paroxysmal and 120 non-paroxysmal AF cases. Clinical follow-up with 12-lead ECGs, 24-h ECGs, trans-telephonic ECGs, and implanted devices was complete in 100%, 63%, 51%, and 16% of cases, respectively. The overall one-year recurrence rate of 59% (range, 24-82%) was dependent on grades of diastolic function (normal - dysfunction grade III) in a multivariable analysis model. Patients with normal diastolic function had the lowest recurrence rates of 24% and 49% after 1 and 3 years of follow-up, respectively (p<0.0001).

CONCLUSION

Diastolic function could serve as a simple summary predictor for AF recurrence, and would facilitate clinical decision-making in AF treatment.

Effect of left ventricular diastolic dysfunction on outcomes of atrial fibrillation ablation

Left ventricular diastolic dysfunction (LVDD) is an important pathogenic factor for atrial fibrillation (AF). There are few data on the effect of LVDD on recurrence of AF after catheter ablation. A cohort of 124 patients (59.9 ± 11.7 years, 73.9% male, and 55% with paroxysmal AF) with recalcitrant AF and normal left ventricular systolic function (left ventricular ejection fraction ≥50%) undergoing ablation was studied. Each patient underwent transthoracic echocardiography, and LVDD was meticulously graded using rhythm-independent (AF or sinus rhythm) transmitral and tissue Doppler parameters. Patients underwent catheter ablation of AF using a stepwise protocol. All patients were followed up at 3, 6, and 12 months with recurrent AF (>30 seconds) captured by electrocardiography and/or 7-day monitor. Kaplan-Meier survival analysis and Cox proportional hazards model were used. There was no LVDD in 72 patients (58%), whereas 33 (26.6%), 10 (8.1%), and 9 (7.3%) patients had grades 1, 2, and 3 LVDD, respectively. AF recurred in 49 patients (39.5%) with median time to recurrence of 248 days. Patients with higher grade of LVDD were increasingly more likely to have recurrence (37.5% for no LVDD and 30.3%, 60%, and 66.7% for grades 1, 2, and 3 LVDD, respectively). Significant LVDD (grade 2 or 3) was an independent predictor of recurrence (hazard ratio 2.6, p = 0.009) after adjusting for persistent (vs paroxysmal) AF and left atrial volume. In conclusion, patients with more severe LVDD have a higher risk of AF recurrence after catheter ablation. These patients may derive less benefit from ablation or may require a more extensive ablation approach.

The predictive value of echocardiographic parameters associated with left ventricular diastolic dysfunction on short- and long-term outcomes of catheter ablation of atrial fibrillation

AIMS

Recurrence of atrial fibrillation (AF) is frequently observed after AF catheter ablation. However, the predictive value of echocardiographic parameters associated with left ventricular diastolic dysfunction (LVDD) has not been well studied.

METHODS AND RESULTS

In 124 consecutive patients (mean age 61 ± 10 years, 60% male) with paroxysmal (n = 70) or persistent AF (n = 54) undergoing AF catheter ablation, mitral early diastolic peak (E-wave) and late peak (A-wave) velocities, E/A ratio, deceleration time (DT) of mitral early velocity, early diastolic mitral annulus peak velocity (e'), and E/e' ratio were determined by transthoracic echocardiography. Early (ERAF) and late AF recurrence (LRAF) were monitored with 7-day Holter electrocardiograms directly after catheter ablation and after 6 and 12 months. Early AF recurrence occurred in 34% of the patients, while LRAF was observed in 27% of the patients. Patients with ERAF had higher E-wave (0.9 ± 0.2 vs. 0.8 ± 0.2 m/s, P = 0.035) and lower A-wave velocity (0.5 ± 0.2 vs. 0.6 ± 0.2 m/s, P = 0.038), higher E/A ratio (1.8 ± 0.9 vs. 1.5 ± 0.9, P = 0.089), and slower DT (214 ± 67 vs. 243 ± 68 ms, P = 0.073), while E/e', left atrial diameter, and left ventricular ejection fraction were similar. In multivariable regression analysis, the E/A ratio was the only independent predictor of ERAF (odds ratio 2.905, 95% confidence interval 1.072-7.870, P = 0.036). None of the echocardiographic parameters influenced the late therapy outcome.

CONCLUSION

Early results of the catheter ablation, but not the late rhythm outcome, are influenced by an impaired mitral inflow pattern, which is associated with LVDD.

Doppler-derived left ventricular negative dP/dt as a predictor of atrial fibrillation or ischemic stroke in patients with degenerative mitral regurgitation and normal ejection fraction

INTRODUCTION

The aim of this study was to investigate the role of Doppler-derived left ventricular (LV) -dP/dt in predicting atrial fibrillation (AF) or ischemic stroke in patients with moderate to severe degenerative mitral regurgitation (MR).

METHODS

Doppler-derived LV -dP/dt was determined from the continuous-wave Doppler spectrum of the MR jet (-dP/dt = 32/time between 3 and 1 m/sec) in 80 patients (mean age 59 ± 16 years, 41% men) with moderate to severe degenerative MR, normal LV ejection fraction (LVEF ≥ 60%), and sinus rhythm at diagnosis. Events were defined as new AF or ischemic stroke.

RESULTS

During a mean follow-up of 18 ± 13 months, there were 9 events (6 new AF, 3 ischemic strokes). Univariate analysis showed that older age, decreased LV -dP/dt, increased LV mass index, and left atrial volume index (LAVI), shortened deceleration time (DT), reduced A' velocity, and elevated E/E' ratio, prolongation of pulmonary venous (PV) atrial reversal (AR) flow duration relative to mitral inflow A-wave duration (AR-Adur) were associated with events. In multivariate Cox regression analysis, Doppler-derived LV -dP/dt (for each 100 mmHg/sec increase, hazard ratio: 0.165, 95% confidence interval: 0.036-0.761, P = 0.021) and E/E' (hazard ratio: 0.820, 95% confidence interval: 0.682-0.987, P = 0.036) were significant independent predictors of AF or ischemic stroke.

CONCLUSIONS

Doppler-derived LV -dP/dt is independently associated with the occurrence of AF or ischemic stroke in patients with moderate to severe degenerative MR and provides additional prognostic information.

Role of Left Ventricular Diastolic Dysfunction in Predicting Atrial Fibrillation Recurrence after Successful Electrical Cardioversion

The role of left ventricular (LV) diastolic dysfunction in predicting atrial fibrillation (AF) recurrence after successful electrical cardioversion is largely unknown. Studies suggest that there may be a link between abnormal LV compliance and the initial development, and recurrence of AF after electrical cardioversion. Although direct-current cardioversion (DCCV) is a well-established and highly effective method to convert AF to sinus rhythm, it offers little else beyond immediate rate control because it does not address the underlying cause of AF. Preservation of sinus rhythm after successful cardioversion still remains a challenge for clinicians. Despite the use of antiarrhythmic drugs and serial cardioversions, the rate of AF recurrence remains high in the first year. Current evidence suggests that diastolic dysfunction, which is associated with atrial volume and pressure overload, may be a mechanism underlying the perpetuating cycle of AF recurrence following successful electrical cardioversion. Diastolic dysfunction is considered to be a defect in the ability of the myofibrils, which have shortened against a load in systole to eject blood into the high-pressure aorta, to rapidly or completely return to their resting length. Consequently, LV filling is impaired and the non-compliant left ventricle is unable to fill at low pressures. As a result, left atrial and pulmonary vein pressure rises, and electrical and structural remodeling of the atrial myocardium ensues, creating a vulnerable substrate for AF. In this article, we review the current evidence highlighting the association of LV diastolic dysfunction with AF recurrence after successful electrical cardioversion and provide an approach to the management of LV diastolic dysfunction to prevent AF recurrence.

Echocardiography In the Prediction of Atrial Fibrillation Recurrence: A Review

Atrial fibrillation (AF) is a very common sustained arrhythmia. Co-morbidities and age signifi cantly accelerate the progression of AF to persistent and permanent forms and the development of complications. The rate of AF recurrence is 10% in the first year after the initial diagnosis (25-50% in the first month after restoration of sinus rhythm) and about 5% per annum thereafter. Left ventricular (LV) diastolic dysfunction degree has been associated with new-onset AF and in the last few years many new parameters to evaluate diastolic function were introduced and validated, even in patients with AF. Aim of this review was to summarize echocardiographic parameters, focusing on new tools, to evaluate patients with AF and to explore the role of echocardiographic evaluation to predict recurrence of the arrhythmia.

Atrium electromechanical interval in left ventricular diastolic dysfunction

BACKGROUND

  Left ventricular (LV) diastolic dysfunction has great effects on the left atrium (LA). A recently developed electromechanical interval (PA-TDI), which was determined as the time interval from the initiation of P wave deflection to the peak of local lateral LA tissue Doppler imaging signal, was reported to be associated with LA electrophysiological properties. The goal of our study was to evaluate the association between the PA-TDI interval and LV diastolic function.

MATERIALS AND METHODS

A total of 224 consecutive patients were enrolled. LV diastolic dysfunction was defined as either (i) impaired relaxation: E/A ratio < 0·75 and E/E' ratio < 10, (ii) pseudonormal pattern: 0·75 ≤ E/A ratio < 1·5 and E/E' ratio > 10 or (iii) restrictive pattern: E/A ratio ≥ 1·5 and E/E' ratio > 10. The PA-TDI intervals were measured and compared between patients with and without diastolic dysfunction.

RESULTS

  Fifty-six per cent of the study population had abnormal diastolic function. The PA-TDI interval was significantly longer in the diastolic dysfunction group than that in the normal group (147·8 ± 18·2 vs. 130·4 ± 17·0 ms, P < 0·01). In patients with diastolic dysfunction, the PA-TDI intervals became progressively longer as the diastolic dysfunction progressed from impaired relaxation (141·2 ± 11·4 ms), pseudonormal pattern (147·6 ± 18·0 ms) to restrictive pattern (164·1 ± 20·9 ms).

CONCLUSIONS

  The PA-TDI interval was significantly longer in patients with LV diastolic dysfunction than those without it. Its prolongation may reflect the severity of atrial remodelling because of the abnormal diastolic function of LV.

Success of Ablation for Atrial Fibrillation in Isolated Left Ventricular Diastolic Dysfunction

Background—

The efficacy of radiofrequency ablation for atrial fibrillation (AF) in patients with left ventricular (LV) systolic dysfunction and isolated diastolic dysfunction is uncertain.

Methods and Results—

A prospective cohort of patients with normal and abnormal LV function underwent ablation for antiarrhythmic drug (AAD)-refractory AF. Three groups were compared: 111 patients with systolic dysfunction, defined as LV ejection fraction (LVEF) ≤40%; 157 patients with isolated diastolic dysfunction but preserved LVEF ≥50%; and 100 patients with normal LV function. The primary end point was AAD-free AF elimination at 1 year after ablation. This end point was achieved in 62% of patients with systolic dysfunction, 75% of those with diastolic dysfunction, and 84% of controls ( P =0.007). AF control on or off AADs was achieved in 76% of patients with systolic dysfunction, 85% of those with diastolic dysfunction, and 89% of controls ( P =0.08). In the systolic dysfunction group, 49% experienced an increase in LVEF by ≥5% after ablation, of which 64% achieved normal LVEF. In the diastolic dysfunction group, 30% of patients demonstrated at least 1 grade improvement in diastolic dysfunction. Multivariable analysis demonstrated an increased relative risk of arrhythmia recurrence of 1.8 (95% CI, 1.1 to 3.1; P =0.02) in systolic dysfunction and 1.7 (1.0 to 2.7; P =0.04) in isolated diastolic dysfunction compared with normal function.

Conclusions—

Although an ablative approach for AF in patients with systolic or diastolic dysfunction is associated with an increased long-term recurrence risk, there is potential for substantial quality-of-life improvement and LV functional benefit.

Cost effectiveness of radiofrequency catheter ablation vs. medical treatment for atrial fibrillation in Japan. -Cost performance for atrial fibrillation-

BACKGROUND

Radiofrequency catheter ablation (RF) has recently become widely available for the treatment of atrial fibrillation (AF) and has broadened treatment options while confusing the selection of medication therapy or RF.

METHODS AND RESULTS

Two drugs for the maintenance of sinus rhythm (Ry) and 2 drugs for control of the pulse rate (Ra) were selected and the costs of medication therapy were calculated. RF procedures were grouped into 2 groups each for persistent or paroxysmal AF (RF) and for chronic AF (RFChr), according to the cost of the devices used. The calculated cost of medication therapy was 5,270-23,560 yen per month. The calculated cost of RF procedures was 1,063,200-2,029,640 yen. The costs of RF corresponded to those of Ry for 3.8-14.3 years. The costs of RFChr corresponded to those of Ra for 16.6-63.9 years. The treatment of complications ranged from 360,000 to 1,241,500 yen.

CONCLUSIONS

From the aspect of medical costs and complications, RF should be considered for the treatment of patients with AF detected early or early-stage AF, whereas treatment for its complications should be given priority in patients with chronic AF associated with reduced cardiac function.