123
I‐MIBG and Ablation for Atrial Fibrillation. Introduction: Excessive sympathetic nervous activity may contribute to atrial fibrillation (AF) recurrences after ablation, but its precise role ...remains controversial. The goals of this study were to assess the effects of AF on the iodine‐123‐metaiodobenzylguanidine (123I‐MIBG) findings and to elucidate its impact on the procedural outcome in patients undergoing a first‐time catheter ablation to treat AF.
Methods and Results:
This study included 88 consecutive patients with paroxysmal (n = 48) or persistent (n = 40) AF who underwent radiofrequency catheter ablation and 123I‐MIBG scintigraphy. Five days after the ablation of AF, 123I‐MIBG scintigraphy was performed during sinus rhythm. Anterior planar imaging was obtained at 15 minutes and 180 minutes and the washout rate of the 123I‐MIBG was calculated. The 123I‐MIBG scintigraphy demonstrated an enhanced adrenergic nervous function (high washout rate) and decreased adrenergic nervous distribution (low heart to mediastinum ratios) in patients with both paroxysmal and persistent AF. During a mean follow‐up period of 13.5 ± 2.2 months after the ablation, 25 (28%) patients had AF recurrences. The univariate predictors of an AF recurrence were the duration of the AF history, left atrial dimension, and washout rate of the 123I‐MIBG. Only the 123I‐MIBG washout rate was a multivariate predictor of an AF recurrence (hazard ratio: 1.6, 95% confidence interval: 1.004–1.125, P = 0.037).
Conclusions:
Excessive sympathetic nervous activation may be one of the mechanisms of AF recurrences. The evaluation of the cardiac nerve activity using 123I‐MIBG scintigraphy shortly after the AF ablation may be a promising tool to predict the patient's outcome. (J Cardiovasc Electrophysiol, Vol. 22, pp. 1297‐1304, December 2011)
Background: Activation imaging with 3-dimensional speckle-tracking echocardiography (3D-STE) aims to visualize the time required for the onset of regional contraction from QRS onset. We hypothesized ...that the optimal setting of activation imaging was associated with electrical activation. This study was designed to determine an optimal setting of activation imaging with 3D-STE in comparison with that of a voltage mapping system and to assess the feasibility of this imaging method. Methods and Results: We enrolled 7 patients who underwent electrical voltage mapping. Regional deformation was measured by area change ratio (ACR) with 3D-STE. Activation imaging data were obtained at 10%, 25%, 50%, and 100% of maximal ACR values as the threshold for onset of regional contraction. Duration of LV electrical intraventricular activation time (IVATelectrical) by voltage mapping and mechanical IVAT (IVATmechanical) by activation imaging was defined as the time difference between the first and latest endocardial activation sites. We obtained 21 data sets under various conduction patterns and pacing configurations. The strongest correlation between IVATmechanical and IVATelectrical was observed at 25% of maximal ACR values (IVATelectrical=0.47 * IVATmechanical+20, R=0.80, P<0.001). Concordance of the first and latest activated segments between activation imaging and voltage mapping was 90.5% at this setting (19 studies). Conclusions: Activation imaging with 3D-STE may be a feasible noninvasive method of dyssynchrony imaging based on electromechanical coupling. (Circ J 2013; 77: 2481–2489)
In patients with persistent atrial fibrillation (AF), an extensive antiarrhythmic drug (AAD) therapy using class III AADs and class I AADs might be more effective in restoring sinus rhythm than class ...I or III AADs alone. However, the significance and efficacy of this treatment before radiofrequency catheter ablation is unclear. The present study included 51 consecutive patients with long-lasting persistent AF (>12 months) in whom ≥2 previous AADs had failed to restore sinus rhythm (SR). Before performing extensive pulmonary vein isolation, extensive AAD therapy for >3 months was attempted. Before ablation, AF had converted to SR in 33 patients (65%; SR group) and had continued in 18 (35%; AF group). The left ventricular ejection fraction had increased (p <0.01) in association with the improved left atrial diameter (p <0.05) and brain natriuretic peptide plasma level (p <0.001) in the SR group. However, these parameters had not improved in the AF group. The AF-free rate without any AADs at 14 months after a single ablation procedure was greater in the SR group (61%) than in the AF group (22%; hazard ratio 2.62, 95% confidence interval 1.22 to 5.63; p = 0.013). No restoration of SR with extensive AAD therapy (odds ratio 4.493, 95% confidence interval 1.143 to 17.658; p <0.05) and sustained AF lasting for >3 years (odds ratio 4.574, 95% confidence interval 1.027 to 20.368; p <0.05) before ablation were associated with AF recurrence after ablation. In conclusion, restoration of SR with improved cardiac function and structural remodeling after extensive AAD therapy might predict favorable outcomes after ablation in patients with long-lasting, persistent AF.
Background: Obstructive sleep apnea (OSA) is often associated with atrial fibrillation (AF), but the impact of radiofrequency catheter ablation (RFCA) for AF on sleep apnea syndrome is unknown. ...Methods and Results: A total of 25 patients (3 women; 61±6 years) with sleep apnea syndrome who underwent RFCA for drug-refractory, persistent AF were studied. Polysomnography was also performed 1 day before and 1 week after RFCA in all patients. The total number of central or OSA or hypopnea events was analyzed and compared. Among the 25 patients who all predominantly had obstructive apnea, the apnea-hypopnea index (AHI; median, 21, interquartile range IQR: 11–38 to median 15, IQR: 7–23; P=0.002) and obstructive type of apnea (median 10, IQR: 6–19 to median 7, IQR: 2–14; P=0.003) decreased after RFCA. In patients in whom sinus rhythm was restored and maintained after RFCA, the AHI decreased after RFCA (median 22, IQR: 15–38 to median 15, IQR: 7–23; P<0.01), but it did not in those who had AF recurrence (median 10, IQR: 9–11 to median 11, IQR: 10–16; P<0.05). There was a significant correlation between the outcome of RFCA and % change in the AHI (rs=0.569, P=0.003). Conclusions: In patients with sleep apnea syndrome and AF, restoring sinus rhythm by RFCA was significantly associated with a decrease in AHI (Clinical Trial Registration: Trial number, UMIN000005538). (Circ J 2012; 76: 2096–2103)
We have developed a noninvasive isochrone activation imaging (AI) system with 3-dimensional (3D) speckle tracking echocardiography (STE), which allows visualization of the wavefront image of ...mechanical propagation of the accessory pathway (ACP) in Wolff-Parkinson-White syndrome.
Patients with manifest Wolff-Parkinson-White syndrome were imaged in 3D-STE AI mode, which quantified the time from QRS onset to regional endocardial deformation. In 2 patients with left- and right-side ACP, we confirmed that intraoperative contact endocardial electric mapping and the 3D-STE AI system showed comparable images pre- and postablation. In normal heart assessment by 3D-echo AI, the earliest activation sites were found at the attachment of the papillary muscles in the left ventricle and midseptum in the right ventricle, and none showed earliest activation at the peri-atrioventricular valve annuli. An analyzer who was unaware of the clinical information assessed 39 ACP locations in 38 Wolff-Parkinson-White syndrome patients using 3D-STE. All showed abnormal perimitral or tricuspid annular activations, and the location of 34 ACP (87%) showed agreement with the successful ablation sites within a 2-o'clock range. Especially for left free wall ACP, 17/18 (94%) showed consistency with the ablation site within a 2 o'clock range. Among 15 ACP at the ventricular septum, 9 (60%) showed early local activation in both right and left sides of the septum.
Isochrone AI with 3D-STE may be a promising noninvasive imaging tool to assess cardiac synchronized activation in normal hearts and detect abnormal breakthrough of mechanical activation from both atrioventricular annuli in Wolff-Parkinson-White syndrome.
There are many reports on the ECG characteristics of idiopathic outflow tract ventricular arrhythmias (OT-VAs) to predict their origin. However, differentiating near regions using 12-lead ECGs is ...still complicated. The synthesized 18-lead ECG derived from the 12-lead ECG can provide virtual waveforms of the right-sided chest leads (V3R, V4R, and V5R) and back leads (V7, V8, and V9). The aim of this study was to develop a simple and useful parameter for differentiating OT-VA origins using the 18-lead ECG.
We studied 28 and 73 patients with idiopathic VAs in a pacemapping study and validation cohort, respectively. In the pacemapping study, several sites out of five different sites were paced in each patient: the anterior and posterior right ventricular OT (RVOT-ant and RVOT-post), right and left coronary cusps (RCC and LCC), and junction of both cusps (RLJ). The 18-lead ECGs during pacemapping among the five sites were compared for establishing a simple parameter to predict VA origins. A novel parameter using 18-lead ECGs was tested prospectively in 73 patients. In the pacemapping study, the dominant QRS morphology pattern in the synthesized V5R significantly differed among those sites (RVOT-ant:Rs, RVOT-post:rS, RCC:QS, RLJ:qR, and LCC:R). The patients in the validation cohort were divided into five groups depending on those QRS morphology patterns during VAs in the synthesized V5R. Each V5R QRS morphology pattern could predict a precise origin of the OT-VAs with an overall accuracy of 75%.
The QRS morphology pattern in V5R was a simple and useful parameter for differentiating detailed OT-VA origins.
The association between circulatory dynamics changes during cryoballoon applications and a successful pulmonary vein isolation (PVI) is unknown. Seventy atrial fibrillation patients who underwent PVI ...with 28-mm second-generation cryoballoons and single 3-min freezes were included. Intra-procedural parameters including circulatory dynamics changes during cryoapplications, were compared between 113 successful applications (30 left superior PVsLSPVs, 30 left inferior PVsLIPVs, 25 right superior PVsRSPVs, and 28 right inferior PVsRIPVs) and 47 failed applications (10 LSPVs, 9 LIPVs, 8 RSPVs, and 20 RIPVs). In all individual PVs, lower nadir balloon temperatures (MinTemps) and longer thawing times (ThawTimes) significantly predicted a successful PVI. In addition, greater systolic blood pressure drops following releasing the PV occlusion (SBP-drops) significantly predicted a successful right PV PVI, and longer elapse times during SBP-drops significantly predicted a successful RIPV PVI. Composite parameters incorporating MinTemps and ThawTimes, SBP-drops, and ThawTimes showed the highest area under the curve to predict a successful left PV (0.876 for LSPVs, 0.851 for LIPVs) and right PV (0.927 for RSPVs, 0.980 for RIPVs) PVI, respectively. If the ThawTime (≥ 30 s) and SBP-drop (≤ − 21 mmHg) cutoff values were achieved for the RIPVs, the positive predictive value was 100%. In contrast, if both criteria were not achieved for the RIPVs, the negative predictive value was 100%. In the second-generation cryoballoon PVI, the MinTemp and ThawTime were significantly associated with acute success for all four PVs. In addition, SBP-drops further improved the accuracy of predicting a successful right PV PVI, especially of the RIPV.
Aim
Frequent ventricular premature contractions (VPCs) may cause haemodynamic deterioration and reversible left ventricular (LV) dysfunction. We aimed to clarify this mechanism.
Methods and results
...The haemodynamics, echocardiographic parameters, and plasma brain natriuretic peptide (BNP) level were assessed in 31 patients with idiopathic, frequent VPCs undergoing radiofrequency catheter ablation. The patients were classified into two groups according to the presence (n = 19) or absence (n = 12) of marked augmentation of the pulmonary capillary wedge pressure (PCWP) following VPCs (VPC‐induced‐PCWP augmentation; VI‐PA). The VI‐PA(+) group was defined as those with a peak PCWP of >15 mmHg measured after a VPC. Before the ablation, the mean PCWP, right atrial pressure (RAP), left ventricular end‐diastolic pressure (LVEDP), and plasma BNP level were significantly greater in the VI‐PA(+) group than in the VI‐PA(–) group. In the VI‐PA(+) group, the mean PCWP, RAP, LVEDP, and cardiac index all improved immediately after a successful ablation. At 7.4 ±0.9 months after the ablation, almost all the echocardiographic parameters and plasma BNP level also significantly improved in the VI‐PA(+) group, and the magnitude of the improvement in those parameters measured was greater in the VI‐PA(+) group than in the VI‐PA(–) group. The left atrial contractions during mitral valve closure during VPCs caused a marked pulmonary venous flow regurgitation and VI‐PA. VPC coupling intervals of <500 ms and the presence of a following P‐wave of <300 ms predicted VI‐PAs with a high accuracy.
Conclusions
The VI‐PA may be the main mechanism of the haemodynamic deterioration in patients with frequent VPCs. This haemodynamically deteriorating subgroup could be identified by the surface electrocardiogram and improved dramatically with catheter ablation.
Several studies have demonstrated a relation between the rennin-angiotensin-aldosterone system and atrial fibrillation (AF), but there are no reports on the effect of eplerenone, a selective ...aldosterone blocker, on the prevention of AF recurrence after radiofrequency catheter ablation (RFCA). The aim of this study was to evaluate the effects of eplerenone on clinical outcomes after RFCA in patients with long-standing persistent AF. A total of 161 consecutive patients with long-standing persistent AF (sustained AF duration 1 to 20 years, mean 3.4 ± 3.8) who underwent RFCA were investigated. Eplerenone was used in 55 patients and not used in the remaining 106 patients. Other conventional pharmacologic agents, including angiotensin-converting enzyme inhibitors or angiotensin type 1 receptor blockers, were used equally in the 2 groups. After 24 months of follow-up, 47% of the patients were free from AF recurrence. The rate of freedom from AF recurrence was significantly greater in the eplerenone group (60%) than in the noneplerenone group (40%) (p = 0.011). By univariate analysis, the duration of sustained AF (p <0.001), left atrial diameter (p = 0.010), left atrial volume index (p = 0.017), and early AF recurrence (p <0.001) were significantly associated with AF recurrence, and the use of eplerenone was associated with maintenance of sinus rhythm after RFCA (p = 0.022). Multivariate Cox regression analysis showed that longer duration of sustained AF (>3 years) (p <0.001) and early AF recurrence (p <0.001) were significantly associated with AF recurrence, and only eplerenone therapy significantly improved maintenance of sinus rhythm (p = 0.017). In conclusion, eplerenone significantly improved maintenance of sinus rhythm after RFCA in patients with long-standing persistent AF.
Catheter ablation is an effective therapy for ventricular fibrillation (VF) arising from the Purkinje system in ischemic heart disease. However, some patients experience newly emergent monomorphic ...ventricular tachycardia (VT) after the ablation of VF. We evaluated the prevalence and mechanism of monomorphic VT after VF ablation.
Twenty-one consecutive patients with primary VF because of ischemic heart disease who underwent catheter ablation were retrospectively analyzed. Twenty of 21 patients were in electrical storm. Ventricular premature contractions triggering VF arose from the left Purkinje system and were targeted for ablation. Before the ablation, 14 of 21 patients had only VF, and the other 7 had VF and concomitant monomorphic VT. Four of the 14 patients with only VF (29%) exhibited newly emergent monomorphic VT after VF ablation. Three of these patients had Purkinje-related VTs, which were successfully eliminated by the ablation of a Purkinje network located in the same low-voltage area as the site of prior successful VF ablation. During a median follow-up of 28 months (interquartile range, 16-68 months), VF recurred in 6 of 21 patients (29%); however, there were neither electrical storms nor monomorphic VT, and all recurring arrhythmias were controlled by medical therapy alone.
Over one fifth of patients with primary ischemic VF experienced newly emergent Purkinje-related monomorphic VT after VF ablation. The circuit of the monomorphic VT associated with the Purkinje network was located in the same low-voltage area as the Purkinje tissue that triggered VF and could be suppressed by additional ablation.
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