Outcomes of cavotricuspid isthmus-dependent flutter ablation: randomized study comparing single vs. multiple catheter procedures-the SIMPLE study

BACKGROUND

Catheter ablation is recommended as first-line therapy for patients with symptomatic typical AFl. Although the conventional multi-catheter approach is the standard of care for cavotricuspid isthmus (CTI) ablation, a single-catheter approach was recently described as a feasible alternative. The present study sought to compare safety, efficacy, and efficiency of single vs. multi-catheter approach for atrial flutter (AFl) ablation.

METHODS

In this randomized multi-center study, consecutive patients referred for AFl ablation (n = 253) were enrolled and randomized to multiple vs. single-catheter approach for CTI ablation. In the single-catheter arm, PR interval (PRI) on the surface ECG was used to prove CTI block. Procedural and follow-up data were collected and compared between the two arms.

RESULTS

128 and 125 patients were assigned to the single-catheter and to the multi-catheter arms, respectively. In the single-catheter arm, procedure time was significantly shorter (37 ± 25 vs. 48 ± 27 minutes, p = 0.002) and required less fluoroscopy time (430 ± 461 vs. 712 ± 628 seconds, p < 0.001) and less radiofrequency time (428 ± 316 vs. 643 ± 519 seconds, p < 0.001), achieving a higher first-pass CTI block rate (55 (45%) vs. 37 (31%), p = 0.044), compared with the multi-catheter arm. After a median follow-up of 12 months, 11 (4%) patients experienced AFl recurrences (5 (4%) in the single-catheter arm and 6 (5%) in the multi-catheter arm, p = 0.99). No differences were found in arrhythmia-free survival between arms (log-rank = 0.71).

CONCLUSIONS

The single-catheter approach for typical AFl ablation is not inferior to the conventional multiple-catheter approach, reducing procedure, fluoroscopy, and radiofrequency time.

Clinical impact of aging on outcomes of cardioneuroablation for reflex syncope or functional bradycardia: Results from the cardionEuroabLation: patiEnt selection, imaGe integrAtioN and outComEs-The ELEGANCE multicenter study

BACKGROUND

Cardioneuroablation (CNA) is a novel treatment for reflex syncope. The effect of aging on CNA efficacy is not fully understood.

OBJECTIVE

The purpose of this study was to assess the impact of aging on candidacy and efficacy of CNA for treating vasovagal syncope (VVS), carotid sinus syndrome (CSS), and functional bradyarrhythmia.

METHODS

The ELEGANCE (cardionEuroabLation: patiEnt selection, imaGe integrAtioN and outComEs) multicenter study assessed CNA in patients with reflex syncope or severe functional bradyarrhythmia. Patients underwent pre-CNA Holter electrocardiography (ECG), head-up tilt testing (HUT), and electrophysiological study. CNA candidacy and efficacy was assessed in 14 young (18-40 years), 26 middle-aged (41-60 years), and 20 older (>60 years) patients.

RESULTS

Sixty patients (37 men; mean age 51 ± 16 years) underwent CNA. The majority (80%) had VVS, 8% had CSS, and 12% had functional bradycardia/atrioventricular block. Pre-CNA Holter ECG, HUT, and electrophysiological findings did not differ across age groups. Acute CNA success was 93%, without differences between age groups (P = .42). Post-CNA HUT response was negative in 53%, vasodepressor in 38%, cardioinhibitory in 7%, and mixed in 2%, without differences across age groups (P = .59). At follow-up (8 months, interquartile range 4-15), 53 patients (88%) were free of symptoms. Kaplan-Meier curves did not show differences in event-free survival between age groups (P = .29). The negative predictive value of a negative HUT was 91.7%.

CONCLUSION

CNA is a viable treatment for reflex syncope and functional bradyarrhythmia in all ages, and is highly effective in mixed VVS. HUT is a key step in postablation clinical assessment.

Preventive substrate ablation in chronic post-myocardial infarction patients with high-risk scar characteristics for ventricular arrhythmias: rationale and design of PREVENT-VT study

BACKGROUND

Recent studies showed that an early strategy for ventricular tachycardia (VT) ablation resulted in reduction of VT episodes or mortality. Cardiac magnetic resonance (CMR)-derived border zone channel (BZC) mass has proved to be a strong non-invasive predictor of VT in post-myocardial infarction (MI). CMR-guided VT substrate ablation proved to be safe and effective for reducing sudden cardiac death (SCD) and VA occurrence.

METHODS

PREVENT-VT is a prospective, randomized, multicenter, and controlled trial designed to evaluate the safety and efficacy of prophylactic CMR-guided VT substrate ablation in chronic post-MI patients with CMR-derived arrhythmogenic scar characteristics. Chronic post-MI patients with late gadolinium enhancement (LGE) CMR will be evaluated. CMR images will be post-processed and the BZC mass measured: patients with a BZC mass > 5.15 g will be eligible. Consecutive patients will be enrolled at 3 centers and randomized on a 1:1 basis to undergo a VT substrate ablation (ABLATE arm) or optimal medical treatment (OMT arm). Primary prevention ICD will be implanted following guideline recommendations, while non-ICD candidates will be implanted with an implantable cardiac monitor (ICM). The primary endpoint is a composite outcome of sudden cardiac death (SCD) or sustained monomorphic VT, either treated by an ICD or documented with ICM. Secondary endpoints are procedural safety and efficiency outcomes of CMR-guided ablation.

DISCUSSION

In some patients, the first VA episode causes SCD or severe neurological damage. The aim of the PREVENT-VT is to evaluate whether primary preventive substrate ablation may be a safe and effective prophylactic therapy for reducing SCD and VA occurrence in patients with previous MI and high-risk scar characteristics based on CMR.

TRIAL REGISTRATION

ClinicalTrials.gov, NCT04675073, registered on January 1, 2021.

Multidetector computed tomography identification of previous ablation lines: insights for left atrial flutter ablation

Funding Acknowledgements

Type of funding sources: None.

Background

Left atrial flutter (LAFL) frequently occurs in patients with history of previous left atrial (LA) ablation. LAFL ablation is still considered a challenging and time-consuming procedure (1). Conduction gaps on ablation lines are frequently due to non-transmural or non-contiguous lesions. It was recently demonstrated that aiding AF ablation procedures with the integration of multidetector computed tomography (MDCT)-derived left atrial wall thickness (LAWT) maps into the navigation system allowed decreasing radiofrequency (RF) delivery, fluoroscopy, and procedure time while obtaining a high rate of first-pass isolation (2).

Purpose

We hypothesized that MDCT-derived 3D-LAWT map could be useful to aid LAFL ablation procedure in patients with previous LA ablation lines.

Methods

Consecutive patients with history of previous LA ablation who underwent LAFL ablation were prospectively enrolled from a single referral center. LAWT three-dimensional maps were obtained from MDCT and integrated into the navigation system. LAWT information was used to focus mapping in the areas of the probable crucial isthmus: the presence of previous ablation lines was searched at the level of linear segments with reduced parietal thickness at the LAWT-maps (LAWT &lt;1mm), while the search for conduction gaps was started at the level of the thicker areas of these lines. Conduction gap was defined as the presence of peak-to-peak bipolar potentials &gt; 0.5 mV at the level of the previous ablation line or as the presence during arrhythmia of a LAT delay &lt;30 ms between contiguous points lying in the same axial plane at the two sides of the line. Ablation was performed transecting the crucial isthmus with the documentation of bidirectional block; ablation first-attempt was guided by color-coded maps by connecting the parts of identified previous ablation lines with reduced LAWT. Finally, RF delivery was adapted to the local LAWT.

Results

Five patients [4 (80%) male, age 62 years (57-73)] were included. LAWT-aided LAFL ablation procedures had a median procedure time of 78 minutes (75-114) and a RF time of 5.9 minutes (4.7-8.5); fluoroscopy time was 3.2 minutes (1.5-3.6) with a fluoroscopy dose of 6.1 Gy*cm2 (2.8-8.2). Mean wall thickness of the gap zone was significantly higher with respect to the thickness of the zones of previous ablation lines (1.8 ± 0.5 mm vs. 1.0 ± 0.4 mm, p=0.047). All patients presented sinus rhythm at the end of the procedure and no acute complication occurred. No patient reported arrhythmic recurrence at 1-year follow-up (Figure 2).

Conclusions

LAWT-aided approach for LAFL ablation can facilitate identifying the wall thinning produced by the previous RF ablation line and the gap (seen as relative wall thickening) acting as the isthmus for the reentry circuit. This, in turn might help analysis of reentry circuits and increase procedure efficacy and efficiency. Further data are needed to reproduce these findings in a larger study cohort.

Personalized persistent atrial fibrillation ablation guided by left atrial wall thickness: a multicenter study

Funding Acknowledgements

Type of funding sources: None.

Background

Pulmonary vein isolation (PVI) has been proven to be effective in treating persistent atrial fibrillation (PeAF), although long-term ablation outcomes have been significantly less satisfactory than in paroxysmal AF (1). A recent personalized PVI approach, aiming for contiguous lesions with ablation index (AI) titration according to the local left atrial wall thickness (LAWT) as per multidetector cardiac tomography (MDCT), has demonstrated to achieve an arrhythmia-free survival &gt; 95% at 12 months in patients with paroxysmal AF (2).

Purpose

We sought to investigate the safety and clinical outcomes of this personalized PVI approach guided by LAWT in patients with PeAF.

Methods

Consecutive patients referred for PeAF first ablation were prospectively enrolled from three referral centers. PeAF was defined in the presence of at least one AF episode sustained beyond 7 days. LAWT three-dimensional maps were obtained from MDCT and integrated into the navigation system. LAWT was categorized into 1 mm layers and AI was titrated to the LAWT. The ablation line was personalized to avoid thicker regions (Figure 1) while encircling PV antrum. Follow-up was scheduled at 1, 3, 6, and every 12-months thereafter.

Results

One hundred twenty-seven patients [89 (70.6%) male, age 64 ± 10 years] were included. 68 (60.7%) patients were hypertensive, 10 (18%) patients suffered of type 2 diabetes, and mean CHA2DS2-VASc score was 2.3 ± 2.1. Mean procedure time was 61 ± 20 minutes and mean fluoroscopy time was 1.3 ± 2.2 minutes. Radiofrequency (RF) time was 9.0 ± 2.3 minutes for the right pulmonary veins with a first-pass isolation in 109 (85.8%) patients and 7.6 ± 1.9 minutes for the left pulmonary veins with first-pass in 110 (86.6%). No major complication occurred. The rate of survival free from AF recurrences at a mean follow-up of 12 ± 6 months was 82% (Figure 2).

Conclusions

Personalized Persistent AF ablation by wide circle PV isolation guided by LAWT, proved to be safe and highly efficient, requiring a low amount of RF delivery, procedure time, and fluoroscopy use, while obtaining a high rate of first-pass isolation and of freedom from AF recurrences.

A novel weighted hybrid clinical and electrocardiographic score to predict the origin of outflow tract ventricular arrhythmias: a multicenter study

Funding Acknowledgements

Type of funding sources: None.

Background

To correctly predict the outflow tract ventricular arrhythmia (OTVA) site of origin (SOO) before the ablation is still a procedural major step, having important implications for correct patient counseling, ablation planning, and periprocedural complication evaluation. Although multiple ECG criteria have been proposed for predicting OTVA SOO, their accuracy and usefulness are still limited as recently (1).

Purpose

The present study sought to prospectively evaluate the accuracy of a previously published Hybrid Score (HS) for prediction of OTVAs with LVOT origin. Besides, multiple ECG measurements of patients with V3 precordial transition (V3PT) OTVA were analyzed to identify potential variables useful to improve the accuracy of the HS (2).

Methods

Consecutive patients (n=105) referred for OTVA ablation were prospectively enrolled from three referral centers. Vascular access and first-mapped ventricle were decided based on the previously published HS, which includes ECG (R/S precordial transition) and clinical information (age, hypertension, and gender). Surface ECGs during the OTVA were analyzed by two independent electrophysiologists to compare the discriminative performance of HS and previous published ECG-alone criteria, to assess their inter-observer variability and to identify potential variables useful to improve the proposed model.

Results

Of the 105 VAs, 70.5% had an RVOT origin and 29.5% an LVOT origin. HS achieved a correct prediction in 90% patients. This rate dropped to 75% in the subgroup of patients with V3PT OTVA. The correct prediction rate of the other ECG-alone criteria in the whole population ranged from 74 to 82% and from 41 to 76% in V3PT patients, and their Cohen’s Kappa coefficient for inter-observer variability assessment ranged from 0.63 to 0.81. R-wave amplitude in V3 was the best ECG parameter for discriminating LVOT origin in V3PT patients. When this parameter was incorporated in the novel Weighted Hybrid Score (WHS) (Figure 1), it correctly classified 99 (94.2%) patients (90% sensitivity, 96% specificity, AUC: 0.97). The WHS discriminatory capacity was maintained in V3PT subgroup, (87% sensitivity, 91% specificity AUC: 0.95). WHS showed a Cohen’s kappa coefficient of 0,82. Finally, WHS was validated in an additional population of 97 patients with OTVAs referred for catheter ablation from three additional external centers; in this testing sample the WHS correctly predicted the SOO in 90% patients and proved to have 89% sensitivity and 90% specificity (AUC: 0.94) for a score ≥2 to predict a LVOT origin.

Conclusions

The novel simple-to-use WHS proved to accurately anticipate the PVC’s SOO and can be introduced in clinical practice for choosing the first chamber to map.

Genetic analysis of aquaporin-4 in neuromyelitis optica

OBJECTIVE

Autoantibodies to aquaporin-4 (AQP4) are specific and pathogenic for neuromyelitis optica (NMO). Therefore, we evaluated whether AQP4 single-nucleotide polymorphisms (SNPs) are associated with susceptibility to NMO or whether mutations that potentially alter AQP4 structure or expression are present in some patients.

METHODS

We genotyped 8 AQP4 SNPs chosen based on their minor allele frequency, location, and novelty in 177 NMO sporadic cases, 14 NMO familial cases, and 1,363 matched controls by TaqMan-based assay. We performed bidirectional sequencing of the promoter (1 kb), exons 0-4, and flanking splice consensus sequences, and the 5' and 3' untranslated regions of 177 sporadic and 14 familial NMO cases.

RESULTS

One of 8 SNPs (minor allele frequency = 0.01) was associated with NMO (NC 18.8; chrom pos. 22695167: T>A): odds ratio (95% confidence interval) = 13.1 (1.4-126.7); p = 0.026. In 3 patients with NMO (2 related), we detected 2 different missense allelic mutations at Arg19 (R19I and R19T). None of the 1,363 control subjects had Arg19 mutations (p = 0.001).

CONCLUSIONS

Except for one uncommon SNP, no tested SNP was associated with NMO, nor were 3 SNP haplotypes, providing no support for the hypothesis that genetic variation in AQP4 accounts for overall susceptibility to NMO. Two different allelic Arg19 missense mutations are specific to NMO and segregated with the disease in one pedigree. Although the pathobiology underlying this is not yet established, their effects on the structure of the M1 isoform N terminus or the regulatory sequence of the M23 isoform by virtue of their location support a role of AQP4 orthogonal array formation on molecular susceptibility to NMO.

Azathioprine: tolerability, efficacy, and predictors of benefit in neuromyelitis optica

OBJECTIVE

To evaluate the efficacy, tolerability, optimal dosing, and monitoring of azathioprine in patients with neuromyelitis optica (NMO).

METHODS

This was a chart review and telephone follow-up study of 99 patients with NMO spectrum of disorders (NMOSD) treated with azathioprine (1994-2009). NMOSD were NMO (2006 diagnostic criteria) or partial NMO forms (NMO-immunoglobulin G seropositive). Wilcoxon signed rank test was used to compare pretreatment and postinitiation of azathioprine (posttreatment) annualized relapse rates (ARR), Expanded Disability Status Scale (EDSS) score, and visual acuity outcome. Linear regression was used to assess the effects of various factors on ARR change and disability.

RESULTS

The median duration of NMOSD symptoms prior to initiation of azathioprine was 2 years (range 1-27); 79 patients were women. Eighty-six patients had NMO and 13 limited NMO versions, including transverse myelitis in 8 and optic neuritis in 5. Median posttreatment follow-up was 22 months. Thirty-eight patients discontinued drug (side effects, 22; no efficacy, 13; lymphoma, 3). Among 70 patients with >12 months follow-up, 48 received ≥2.0 mg/kg/day (ARR: pretreatment, 2.20; posttreatment, 0.52); 22 received <2.0 mg/kg/day (ARR: pretreatment, 2.09; posttreatment, 0.82); 52 received concomitant prednisone (ARR: pretreatment, 2.20; posttreatment, 0.89) and 18 did not (ARR: pretreatment, 1.54; posttreatment, 0.23); p < 0.0001 for each comparison. EDSS was stable or improved despite ongoing attacks in 22 patients (31%). Twenty-six patients tolerated azathioprine and were relapse-free (37%, median follow-up 24 months; range 12-151). Mean corpuscular volume increase influenced ARR change (p = 0.049).

CONCLUSIONS

Azathioprine is generally effective and well-tolerated. Early initiation, adequate dosing, and hematologic parameter monitoring may optimize efficacy.

CLASSIFICATION OF EVIDENCE

This study provides Class IV evidence that azathioprine is effective for reducing relapse rates and improving EDSS and visual acuity scores in patients with NMO spectrum of disorders.

Familial neuromyelitis optica

BACKGROUND

Detection of aquaporin-4-specific immunoglobulin G (IgG) has expanded the spectrum of neuromyelitis optica (NMO). Rare reports of familial aggregation have suggested a component of genetic susceptibility but these reports mostly antedated the discovery of the NMO-IgG biomarker and recently updated diagnostic criteria.

METHODS

We report a case series describing the demographic, clinical, neuroimaging, and NMO-IgG serologic status of 12 multiplex NMO pedigrees with a total of 25 affected individuals.

RESULTS

Twenty-one patients (84%) were women. Families were Asian (n = 5), Latino (n = 4), white (n = 1), or African (n = 2). Apparent transmission was either maternal (n = 5) or paternal (n = 2). In 1 family, 3 individuals had NMO; in the others, 2 individuals were affected. Sibling pairs (n = 6), parent-child (n = 4), and aunt-niece (n = 3) pairs were observed. Nineteen patients (76%) were NMO-IgG positive. Twelve (48%) had clinical or serologic evidence of another autoimmune disease. Familial occurrence of NMO occurs in approximately 3% of patients with well-established diagnosis of NMO.

CONCLUSIONS

A small proportion of patients with NMO have relatives with this condition, but familial occurrence is more common than would be expected from its frequency in the general population. Familial NMO is indistinguishable from sporadic NMO based on clinical symptoms, age at onset, sex distribution, and frequency of NMO-IgG detection. One or 2 generations were affected and affected individuals represented a small fraction of family members. Taken together, these data suggest complex genetic susceptibility in NMO.

Low efficacy of atrial fibrillation ablation in severe obstructive sleep apnoea patients

AIMS

Atrial fibrillation (AF) ablation efficacy varies according to patients' clinical characteristics. Although the association of obstructive sleep apnoea (OSA) and AF is well established, data on AF ablation efficacy in OSA are scarce. The aim of this study was to clarify the effect of OSA on the outcome of AF ablation.

METHODS AND RESULTS

A series of 174 consecutive patients without polysomnography submitted to circumferential pulmonary vein ablation were included in the study. All patients were assessed by Berlin Questionnaire (BQ) and underwent an echocardiogram and a clinical evaluation. Patients with a high BQ score, indicating high risk for OSA, participated in a sleep study. Diagnoses were classified according to the apnoea-hypoapnoea index (AHI) as mild (AHI < 10/h), non-severe (AHI < 30/h), or severe (AHI >or= 30/h) OSA. Follow-up consisted of outpatient visits and 24 or 48 h Holter monitoring at 1, 4, and 7 months, and every 6 months thereafter. Any episode of AF or left atrial (LA) flutter was considered recurrence. Fifty-one (29.3%) patients had high BQ scores. The sleep study showed that 17 (9.8%) and 25 (14.4%) of these patients had non-severe and severe OSA, respectively. One-year arrhythmia-free probability after a single ablation procedure was 48.5% in patients with low risk for OSA (low BQ score or AHI < 10/h), 30.4% in the non-severe OSA group (10 < AHI < 30/h) and 14.3% in the severe OSA group (AHI >or= 30). Anteroposterior LA diameter [hazard ratio (HR) = 1.046, 95% confidence interval (CI): 1.005-1.089; P = 0.029] and severe OSA (HR = 1.870, 95% CI: 1.106-3.161; P = 0.019) were the independent predictors of arrhythmia recurrence.

CONCLUSION

In patients with AF ablation, the presence of severe OSA is an independent predictor for AF ablation failure.

Left ventricular systolic dysfunction by itself does not influence outcome of atrial fibrillation ablation

AIMS

The objective of the study was to analyse the influence of left ventricular (LV) ejection fraction (EF) on the outcomes of atrial fibrillation (AF) ablation after a first procedure. Pre-procedural predictors of recurrences after AF ablation can be useful for patient information and selection of candidates. The independent influence of LV systolic dysfunction on recurrence rate has not been studied.

METHODS AND RESULTS

A case-control study (1:1) was conducted with a total of 72 patients: 36 cases (depressed LVEF) and 36 controls (normal LVEF). Patients were matched by left atrial diameter (LAD), the presence of arterial hypertension, and other variables that might influence the results (age, gender and paroxysmal vs. persistent AF). There were no statistical differences in the variables used to perform the matching. Patients with depressed LVEF had higher LV end diastolic diameter (55.6 +/- 6.2 vs. 52.4 +/- 5.5, P = 0.03), higher LV end systolic diameter (40.3 +/- 6.9 vs. 32.6 +/- 4.3, P < 0.001), lower LVEF (41.4 +/- 8.0 vs. 63.1 +/- 5.5, P < 0.001) and were more likely to have structural heart disease. After a mean follow-up of 16 +/- 13 months, survival analysis for AF recurrences showed no differences between patients with depressed vs. normal LVEF (50.0 vs. 55.6%, log rank = 0.82). Cox regression analysis revealed LAD to be the only variable correlated to recurrence [OR 1.11 (1.01-1.22), P = 0.03]. Analysis at 6 months showed a significant increase in LVEF (43.23 +/- 7.61 to 51.12 +/- 13.53%, P = 0.01) for the case group.

CONCLUSION

LV systolic dysfunction by itself is not a predictor of outcome after AF ablation. LAD independently correlates with outcome in patients with low or normal LVEF.

Circumferential pulmonary vein ablation: does use of a circular mapping catheter improve results? A prospective randomized study

BACKGROUND

The best method for performing atrial fibrillation (AF) ablation is still under debate. The importance of using a circular mapping (CM) catheter for assessing isolation of the pulmonary vein (PV) antrum on the outcome of the procedure has not been clearly established.

OBJECTIVE

The purpose of this study was to evaluate whether use of a CM catheter improves the arrhythmia-free proportion after circumferential pulmonary vein ablation (CPVA).

METHODS

A series of 146 consecutive patients (83% males, age 53 +/- 10 years, 53% paroxysmal AF) were randomized to two ablation strategies. In both groups, ipsilateral PV encirclement was performed until disappearance or dissociation of the local electrogram within the surrounded area. In the first group, only the radiofrequency catheter was used to both map and ablate (CPVA group, n = 73). In the other group, a CM catheter was added to assess the electrical activity of the PV antrum (CPVA-CM group, n = 73). An ablation line along the left atrial roof was also created in all patients.

RESULTS

Procedural and fluoroscopic times were longer in the CPVA-CM group (P <.05). Severe procedure-related complications occurred in 1 (1.4%) patient in the CPVA group and in 3 (4.1%) patients in the CPVA-CM group (P = .317). After mean follow-up of 9 +/- 3 months, 31 (42.5%) patients in the CPVA group and 47 (64.4%) patients in the CPVA-CM group were arrhythmia-free without antiarrhythmic medication (P = .008).

CONCLUSION

Use of a CM catheter to ensure isolation of the PV antrum improved the success of CPVA but increased some procedural requirements.

Posterior reversible encephalopathy syndrome in neuromyelitis optica spectrum disorders

BACKGROUND

Posterior reversible encephalopathy syndrome (PRES) is characterized by vasogenic subcortical edema without infarction. It has been associated with hypertensive crises and with immunosuppressive medications but not with neuromyelitis optica (NMO).

METHODS

We reviewed the clinical and neuroimaging features of five NMO-immunoglobulin G (IgG) seropositive white women who experienced an episode of PRES and had a coexisting NMO spectrum disorder (NMOSD). We also tested for the aquaporin-4 (AQP4) water channel autoantibody (NMO-IgG) in 14 patients from an independently ascertained cohort of individuals with PRES.

RESULTS

All five patients developed abrupt confusion and depressed consciousness consistent with PRES. The encephalopathy resolved completely within 7 days. Comorbid conditions or interventions recognized to be associated with PRES included orthostatic hypotension with supine hypertension, plasma exchange, IV immunoglobulin treatment, and high-dose IV methylprednisolone. Brain MRI studies revealed bilateral T2-weighted (T2W) hyperintense signal abnormalities, primarily in frontal, parieto-occipital, and cerebellar regions. Three patients had highly symmetric lesions and three had gadolinium-enhancing lesions. Follow-up neuroimaging revealed partial or complete disappearance of T2W hyperintensity or gadolinium-enhancing lesions in all five patients. Patients with PRES without NMOSD were uniformly NMO-IgG seronegative.

CONCLUSIONS

Brain lesions in some patients with neuromyelitis optica spectrum disorder (NMOSD) may be accompanied by vasogenic edema and manifest as posterior reversible encephalopathy syndrome (PRES). Water flux impairment due to aquaporin-4 autoimmunity may predispose to PRES in patients with NMOSD who experience blood pressure fluctuations or who are treated with therapies that can cause rapid fluid shifts.

NMO-IgG predicts the outcome of recurrent optic neuritis

OBJECTIVE

To determine the prognostic value of neuromyelitis optica (NMO)-immunoglobulin G (IgG) in patients with recurrent optic neuritis (ON). The aquaporin-4-specific serum autoantibody, NMO-IgG, is a biomarker for NMO and relapsing transverse myelitis. Recurrent ON may herald multiple sclerosis (MS) or NMO, or it may occur as an isolated syndrome. The prognosis and response to therapy differs in each of these contexts.

METHODS

We evaluated 34 patients who were tested for NMO-IgG between 2000 and 2007 and who had two or more episodes of ON without satisfying a diagnosis of MS or NMO prior to serologic testing. Clinical data were available for 25 Mayo Clinic patients (5 NMO-IgG positive and 20 NMO-IgG negative) and for an additional 9 seropositive patients whose serum was referred to the Mayo Clinic Neuroimmunology laboratory for testing.

RESULTS

Twenty percent of the patients with recurrent ON seen at Mayo Clinic were seropositive. All NMO-IgG-positive patients (vs 65% NMO-IgG-negative patients) had at least one attack with visual acuity in the affected eye worse than 20/200 (p = 0.05). In seropositive patients for whom long-term follow-up was possible (median 8.9 years after the initial ON), 6 of 12 (50%) experienced an episode of myelitis and fulfilled criteria for NMO. In contrast, 1 of 15 seronegative patients (6.7%) fulfilled McDonald criteria for MS (p = 0.03). Seropositive patients had a final visual score which was worse than that of seronegative patients (p = 0.02).

CONCLUSIONS

Neuromyelitis optica (NMO)-immunoglobulin G seropositivity predicts poor visual outcome and development of NMO. Seropositive recurrent optic neuritis is a limited form of NMO.

Left atrial contractility is preserved after successful circumferential pulmonary vein ablation in patients with atrial fibrillation

INTRODUCTION

Circumferential pulmonary vein ablation (CPVA) for atrial fibrillation (AF) consists of creating extensive lesions in the left atrium (LA). The aim of the study was to evaluate changes in LA contractility after ablation and their relationship with procedure outcome.

METHODS AND RESULTS

A series of 90 consecutive patients underwent cardiac magnetic resonance imaging (MRI) before and 4-6 months after CPVA. Only patients in sinus rhythm during both imaging acquisitions were included in the study to measure LA end-diastolic (LAmax) and LA end-systolic (LAmin) volumes. Fifty-five patients were finally analyzed (41 men, 52 +/- 11 years, 74% paroxysmal AF). During a mean follow-up of 12 +/- 7 months and after 1.2 +/- 0.3 ablation procedures, 38 patients (69%) were arrhythmia-free (group I), and the remaining 17 patients had recurrences (group II). There was a significant decrease in mean LAmax volume in both groups, whereas mean LAmin volume only decreased in group I. Mean LA ejection fraction (EF) was preserved after CPVA in group I (40 +/- 11% vs 38 +/- 10%; P = 0.27) but decreased in patients with arrhythmia recurrences (37 +/- 10% vs 27 +/- 10%; P < 0.001). In fact, LA EF remained stable or increased in 68% of patients without arrhythmia recurrences.

CONCLUSIONS

LAmax volume reduction following CPVA occurs regardless of the clinical efficacy of the procedure, whereas mean LAmin volume only decreased in patients without recurrences. LA EF was preserved or even increased in most patients with successful CPVA.

Selective segmental ostial ablation and circumferential pulmonary veins ablation. Results of an individualized strategy to cure refractory atrial fibrillation

AIMS

Previous studies have analyzed the efficacy of atrial fibrillation (AF) ablation in series of consecutive patients or comparing methods in a randomized way, without taking account individual patient characteristics. The purpose of this study was to evaluate the results of a strategy based on selecting the ablation method according to patient clinical features in drug-refractory paroxysmal or persistent AF.

METHODS AND RESULTS

Patients with left atrial diameter < or =40 mm and runs of atrial tachycardia of more than ten beats during Holter recording were selected for selective segmental ostial ablation (SSOA) in order to disconnect only those pulmonary veins with electrical potentials. The remaining patients underwent circumferential pulmonary veins ablation (CPVA) to modify left atrial substrate by extensive linear lesions. A group of 131 consecutive patients were included. Mean follow-up was 21.5 +/- 15.2 months. In paroxysmal AF, 44 and 55 patients were selected for SSOA and CPVA, respectively, and the efficacy of the procedure was similar in the two groups (77 vs 74%; log-rank test p = NS). In persistent AF, 6 and 26 patients underwent SSOA and CPVA, respectively, and greater efficacy was observed in the second group (17 vs 65%; log-rank test p = 0.004).

CONCLUSIONS

Selecting the ablation method according to patient characteristics achieved good results and reduced the overall amount of ablated atrial tissue in patients with paroxysmal AF. However, in persistent AF the SSOA technique showed very limited efficacy despite the previous patient selection and a CPVA-like procedure may be the appropriate choice in all cases.

Pre-procedural predictors of atrial fibrillation recurrence after circumferential pulmonary vein ablation

AIMS

The success rate of circumferential pulmonary vein ablation (CPVA) to treat atrial fibrillation (AF) ranges from 60 to 90%, depending on the series. The objective of the study was to identify predictors of AF recurrence after a standardized CPVA procedure.

METHODS AND RESULTS

A series of 148 consecutive patients undergoing CPVA for symptomatic paroxysmal (60.8%), persistent (23.6%), or permanent (15.5%) AF refractory to antiarrhythmic drugs were included in the study. CPVA with the creation of supplementary block lines along the posterior wall and mitral isthmus was performed and a minimum of 6 months follow-up completed in all patients. Structural heart disease was present in 19.6% and hypertension in 33.8% of patients. After 13.1 +/- 8.4 months follow-up, 73.6% of patients were free of AF recurrences after a mean of 1.18 +/- 0.45 procedures/patient (one procedure in 85.2%, two procedures in 14.8%, and three procedures in 2.7%). Univariable analysis showed that the risk of AF recurrence increases with age (HR 1.03; 95% CI 1.00-1.06, P = 0.031), with the presence of previous hypertension (HR 2.7; 95% CI 1.43-5.07, P = 0.002), and if AF is permanent (HR 2.23; 95% CI 1.08-4.59, P = 0.042). In addition, larger anteroposterior left atrial diameter (LAD) (HR 1.11; 95% CI 1.05-1.18, P = 0.001) and larger left ventricular end-systolic diameter (HR 1.07; 95% CI 1.00-1.15, P = 0.029) prior to the procedure were associated with AF recurrence after CPVA. Cox regression analysis showed that hypertension (OR = 2.8; 95% CI 1.5-5.4; P = 0.002) and LAD (OR = 1.1; 95% CI 1.05-1.19, P < 0.001) were independent predictors of AF recurrence. The mean predicted proportion of patients with AF recurrence after CPVA of the multivariable model showed a linear relationship with the increase in LAD prior to the procedure. The presence of hypertension further increased the mean predicted proportion of patients with AF recurrence at each LAD.

CONCLUSION

Hypertension and LAD are independent pre-procedural predictors of AF recurrence after CPVA to treat AF. These data may help in patient selection for AF ablation.

Incidence of Pulmonary Vein Stenosis in Patients Submitted to Atrial Fibrillation Ablation: A Comparison of the Selective Segmental Ostial Ablation vs the Circumferential Pulmonary Veins Ablation

INTRODUCTION

Pulmonary vein (PV) stenosis is an important complication of the AF ablation and could be underestimated if their assessment is not systematically done. Selective Segmental Ostial Ablation (SSOA) and Circunferential Pulmonary Veins Ablation (CPVA) have demonstrated efficacy in atrial fibrillation (AF) treatment. In this study the real incidence of PV stenosis in patients (pts) submitted to both SSOA and CPVA was compared.

METHODS

Those pts with focal activity and normal left atrial size were submitted to SSOA, remaining pts were submitted to CPVA to treat refractory, symptomatic AF. Contrast enhanced magnetic resonance angiography (MRA) was routinely performed in all patients 4 months after the procedure.

RESULTS

A series of 73 consecutive patients (mean age of 51 +/- 11 years; 75% male) were included. SSOA was performed in 32 patients, and the remaining 41 patients underwent to CPVA, obtaining similar efficacy rates (72% vs 76% arrythmia free probability at 12 months; log rank test p = NS). Six patients had a significant PV stenosis, all in SSOA group none in CPVA group (18.8% vs 0%; p = 0.005). All patients were asymptomatic and the stenosis was detected in routine MRA. No predictors of stenosis has been identified analysing patient procedure characteristics.

CONCLUSION

PV stenosis is a potential complication of SSOA not seen in CPVA. The study confirms than MRA is useful for identifying patients with asymptomatic PV stenosis.