P1383Procedural differences during de novo paroxysmal atrial fibrillation ablation with a contact force-sensing ablation catheter between Europe and U.S

Background

Although pulmonary vein isolation (PVI) is considered the standard approach of atrial fibrillation ablation worldwide, procedural practice during the ablation varies by geographical region. Using the same magnetic sensor enabled contact force-sensing ablation catheter for the treatment of de novo paroxysmal atrial fibrillation, a comparison of procedural detail between Europe and U.S operators can provide insights into geographic specific clinical practices. 

Purpose

To characterize and compare procedural differences during paroxysmal atrial fibrillation ablation performed with a magnetic sensor enabled contact force-sensing catheter across European and U.S. centers. 

Methods

Procedural data were prospectively collected in clinical cases performed with a new magnetic sensor enabled, contact force ablation catheter within the first 6 months of use at participating centers in Europe and the U.S. Procedure time, PVI time, PVI confirmation method, fluoroscopy usage and lesion delivery parameters were analyzed based on geographies. 

Results

A total of 131 cases across 35 centers in 11 European countries, and 95 cases across 26 U.S. centers were analyzed. Target geometry was created with the ablation catheter in 94 out of 131 (71.8%) European cases, while only 5 out of 95 U.S. cases (5.3%) reported the use of the ablation catheter for model creation. Although a steerable sheath (64.1% and 67.3%) was commonly used with the ablation catheter in both geographies, difference in the utilization of bidirectional contact force catheter (52.7% and 90.5%) and the automated lesion marking module (76.3% and 81.1%) were observed in European and U.S. cases, respectively. The use of adenosine or isoproterenol to confirm PVI was reported in 25% and 64% of the European and U.S. cases. Average waiting periods were 18.2 minutes and 26.5 minutes from reported European and U.S. cases. Total procedural time, mapping time, and fluoroscopy time were similar between European and U.S. cases. (Table). First pass PVI were 66.4% and 72.6% for European and U.S. cases, respectively.

Conclusion

Total procedural time and RF time were similar between European and U.S. cases during de novo paroxysmal atrial fibrillation ablation using the same ablation catheter. Differences in workflow including the use of a mapping catheter for geometry creation and waiting period were observed between the two geographies.

Summary of procedural details De novo PAF N Procedural time(min) Mapping time (min) PVI time (min) Total RF time (min) Fluoro time( min) Europe 131 144.0 ± 56.9 16.6 ± 17.1 69.8 ± 35.0 33.2 ± 15.6 11.6 ± 10.1 U.S. 95 137.6 ± 64.8 18.1 ± 23.5 58.8 ± 31.5 32.3 ± 22.2 12.0 ± 15.8

P981Comparison of automark utilization and lesion metric target during paroxysmal atrial fibrillation ablation with a contact force-sensing ablation catheter: European and U.S. multicenter Experiences

Background

Accurate delivery of transmural lesion is associated with improved durability of pulmonary vein isolation and reduced reconduction. Lesion quality depends on multiple parameters such as radiofrequency power, tissue-catheter contact, duration of energy application, and catheter tip temperature. Consequently, energy delivery parameters vary based on individual operators’ preferences and procedural needs.

Purpose

To characterize and compare the utilization of automated lesion marking feature and lesion delivery parameters used during paroxysmal atrial fibrillation ablation performed with a magnetic sensor enabled contact force-sensing catheter across European and U.S. centers.

Methods

Procedural data were prospectively collected in clinical cases performed with a new magnetic sensor enabled, contact force ablation catheter within the first 6 months of use at participating centers in Europe and the U.S. Use of bidirectional CF catheters, steerable sheaths, automated lesion marking software and associated lesion delivery parameters during paroxysmal atrial fibrillation ablation were evaluated.

Results

A total of 149 cases across 37 centers in 11 European countries, and 112 cases across 31 U.S. centers were analyzed. A bidirectional contact force catheter (56.4% and 90.2%), a steerable sheath (65.8% and 69.6%), and the automated lesion marking module (77.9% and 90.2%) were used in most European and U.S. cases, respectively. The most commonly reported energy delivery parameters were: lesion index (LSI), Force-Time Integral (FTI), and time from European cases; LSI, average force, and FTI for U.S. cases (Table). Target LSI values were recorded for 126 cases in Europe and 34 in the U.S, ranging from 3 to 6. In anterior/roof segments, most common LSI target values for anterior/roof and posterior/inferior segments were 6 (42.9%) and 5 (51.2%) in Europe, and 5.5 (44.1%) and 5 (54.5%) in the U.S. PVI was confirmed with an average of 20.3 minutes waiting period (69.1%) for European cases and exit block (57.1%) in U.S. cases. First pass PVI were 67.1% and 74.4% for European and U.S. cases, respectively.

Conclusion

Energy delivery parameters and PVI confirmation method varied considerably by geography during paroxysmal atrial fibrillation ablation using the magnetic sensor enabled, contact force ablation catheter. Further study on efficacy implication on these differences in practice should be examined.

Energy delivery parameters used Paroxysmal AF N LSI FTI Time Imp Drop Avg Force Other N/A Europe 149 44.0 % 13.4 % 7.0 % 6.0 % 2.4 % 1.0 % 26.2 % U.S. 112 31.2% 17.9 % 6.2 % 8.0 % 23.2 % 11.7 % 1.8 % Energy delivery parameters used in paroxysmal AF ablation in Europe and U.S.

EUS-FNA versus biliary brushings and assessment of simultaneous performance in jaundiced patients with suspected malignant obstruction

CONTEXT

Individuals with suspected malignant biliary obstruction commonly undergo ERCP for drainage and tissue sampling via biliary brushings. EUS with EUS-FNA facilitates staging and potentially more accurate tissue sampling.

OBJECTIVE

The aim is to compare the diagnostic performance of EUS-FNA and ERCP with biliary brushings (ERCP-BB) in the diagnosis of pancreatobiliary carcinoma and the utility of combining the two procedures under conscious sedation.

DESIGN

Retrospective analysis of a prospectively maintained database.

PATIENTS

Thirty-seven patients with suspected malignant obstructive jaundice underwent 39 paired procedures, either combined (n=22) or within a few days (n=17).

RESULTS

Using strict cytological criteria the sensitivity of EUS-FNA in the diagnosis of malignancy was 52.9% (95% CI: 35.1-70.2%) versus 29.4% (95% CI: 15.1-47.5%) for ERCP-BB. Combining the two tests improved sensitivity to 64.7% (95% CI: 46.5-80.3%) which was significantly better than ERCP-BB alone (P=0.001) but not EUS-FNA alone (P=0.125). When both procedures were performed under the same conscious sedation, there was a significant difference (P=0.031) between the sensitivity of EUS-FNA (52.6%; 95% CI: 28.9-75.6%) and that of ERCP-BB (21.1%; 95% CI: 6.1-45.6%). When both procedures were performed together the mean±SD in-room time was 79±14 min (range: 45-105 min). Two of the patients (9.1%) had a complication.

CONCLUSIONS

In patients undergoing EUS-FNA and ERCP-BB under the same sedation, EUS-FNA was significantly more sensitive in diagnosing malignancy. Combining the results of both tests improved diagnostic accuracy. Combining therapeutic ERCP and EUS-FNA under the same conscious sedation is feasible, with a complication rate similar to that of ERCP alone.

The clinical significance of antinucleolar antibodies

BACKGROUND

The importance of antinucleolar antibodies seen by indirect immunofluorescence on HEp-2 cells, although associated with systemic sclerosis (SSc), in unselected patients is unknown.

AIMS

To determine the true clinical significance of antinucleolar antibodies in an unselected patient population.

METHODS

Antinucleolar antibody (ANoA) positive samples were identified in the immunology laboratory during routine autoimmune screening tests; case notes were reviewed using a standard proforma.

RESULTS

104 patients with ANoA were identified and ANoA+ samples were subclassified into homogeneous, clumpy and speckled antinucleolar types. SSc was evident in only two (1.8%) patients. Other connective tissue diseases were identified in 33 patients (32%); 22 patients (21%) had evidence of various malignancies. Both disordered liver function and anaemia were seen in 22 patients and were the commonest laboratory abnormalities.

CONCLUSIONS

Neither the presence nor subtype of ANoA is specific for systemic sclerosis. Laboratory comments appended to results should reflect this fact.

Surface atrial frequency analysis in patients with atrial fibrillation: assessing the effects of linear left atrial ablation

INTRODUCTION

Our group has shown previously that measurements of atrial frequency can be obtained from surface 12-lead ECG recordings of patients during atrial fibrillation (AF), using a combination of principal component and Fourier transform algorithms. Such measurements are reproducible over time and change with drug manipulation of the arrhythmia.

AIMS

To determine whether linear left atrial ablation, using a combination of "roof" and "mitral isthmus" lines results in changes in surface atrial frequency during AF and to assess the contribution of each individual line when sited sequentially.

METHODS AND RESULTS

Computerized recordings from 26 patients, who had undergone linear ablation procedures for AF, were reviewed. The atrial signal was extracted from the 12-lead ECG data by principal component analysis and the main frequency component identified using Fourier analysis. Atrial frequency before and after these two standard ablation lines was compared. Atrial frequency decreased significantly after the combination of roof and mitral isthmus lines (5.66 vs 5.15 Hz) and when either roof (5.61 vs 5.13 Hz) or mitral isthmus (5.89 vs 5.75 Hz) lines were sited first. However, only the roof line led to a significant reduction in atrial frequency when sited second (5.64 vs 5.49 Hz).

CONCLUSIONS

Measurements of atrial frequency can be obtained from surface 12-lead ECG recordings during AF and change as predicted in response to linear left atrial ablation. This technique may be useful in assessing antiarrhythmic treatments for AF.

Surface Atrial Frequency Analysis in Patients with Atrial Fibrillation:. A Tool For Evaluating the Effects of Intervention

INTRODUCTION

The aims of this study were to evaluate (1) principal component analysis as a technique for extracting the atrial signal waveform from the standard 12-lead ECG and (2) its ability to distinguish changes in atrial fibrillation (AF) frequency parameters over time and in response to pharmacologic manipulation using drugs with different effects on atrial electrophysiology.

METHODS AND RESULTS

Twenty patients with persistent AF were studied. Continuous 12-lead Holter ECGs were recorded for 60 minutes, first, in the drug-free state. Mean and variability of atrial waveform frequency were measured using an automated computer technique. This extracted the atrial signal by principal component analysis and identified the main frequency component using Fourier analysis. Patients were then allotted sequentially to receive 1 of 4 drugs intravenously (amiodarone, flecainide, sotalol, or metoprolol), and changes induced in mean and variability of atrial waveform frequency measured. Mean and variability of atrial waveform frequency did not differ within patients between the two 30-minute sections of the drug-free state. As hypothesized, significant changes in mean and variability of atrial waveform frequency were detected after manipulation with amiodarone (mean: 5.77 vs 4.86 Hz; variability: 0.55 vs 0.31 Hz), flecainide (mean: 5.33 vs 4.72 Hz; variability: 0.71 vs 0.31 Hz), and sotalol (mean: 5.94 vs 4.90 Hz; variability: 0.73 vs 0.40 Hz) but not with metoprolol (mean: 5.41 vs 5.17 Hz; variability: 0.81 vs 0.82 Hz).

CONCLUSION

A technique for continuously analyzing atrial frequency characteristics of AF from the surface ECG has been developed and validated.

Effect of mitral valve repair/replacement surgery on atrial arrhythmia behavior

BACKGROUND AND AIMS OF THE STUDY

Few data have been published on the effects of mitral valve surgery on atrial rhythm. The study aims were to determine the effects of surgery on: (i) persistence of atrial fibrillation (AF); (ii) measures of left atrial and ventricular dimensions; and (iii) ECG P-wave duration.

METHODS

A retrospective case-note review of 92 patients with chronic mitral regurgitation was undertaken. Variables determined included prevalence and duration of AF; incidence of new-onset or persistence of AF after surgery; rhythm changes in relation to age, gender, left atrial and ventricular dimensions and function, anti-arrhythmic drug usage and ECG P-wave duration in sinus rhythm prior to surgery.

RESULTS

Only 4/47 (8.5%) patients with any history of AF before surgery were in sinus rhythm at six months after surgery. All 28 patients with persistent AF for >12 months and 41/45 (91%) in sinus rhythm before surgery retained these rhythms after surgery. The left atrial dimension was decreased after surgery, in the whole group (51.3 +/- 9.0 versus 48.4 +/- 9.5 mm; p = 0.011) and in the subgroup in sinus rhythm, but not in the subgroup in AF. The left ventricular end-diastolic dimension decreased in the group as a whole (60.6 +/- 6.2 versus 53.0 +/- 8.7 mm; p = 0.0001) and in both subgroups after surgery. In 24 patients with 12- lead ECGs in sinus rhythm before and three months after surgery, P-wave duration remained unchanged. However, this measure decreased in the 18 patients in sinus rhythm consistently, but increased in the six patients continuing to have paroxysmal AF after surgery.

CONCLUSION

Mitral valve surgery alone restored sinus rhythm in only 8.5% of patients with any previous history of AF. Concomitant anti-arrhythmic procedures should be considered for all patients with AF who undergo mitral valve surgery.

beta-Adrenergic subsensitivity induced by chronic administration of terbutaline

The effect of 6-day courses of terbutaline and ephedrine on the metablic and hemodynamic responses to a 4-hour epinephrine infusion were compared in the same five individuals. Terbutaline suppressed the subsequent lactate response to epinephrine more than ephedrine did. The suppression of blood glucose response to epinephrine was similar for the two drugs. Ephedrine profoundly altered the hemodynamic responses to epinephrine causing significantly higher systolic and diastolic blood pressures and slower pulse. Terbutaline did not alter the systolic blood pressure during subsequent epinephrine infusion, and had less effect than ephedrine on the diastolic pressure and heart rate during the infusion. The effect of terbutaline on physiologic responses to exercise was studied, employing both brief strenuous and prolonged moderate treadmill exercice. Following 6 days of terbutaline the blood glucose and lactate levels during and following exercise were consistently but not markedly reduced. There was no effect on hemodynamic responses or on blood levels of free fatty acids, nor did exercise tolerance appear to be reduced. The 6-day course of terbutaline did not alter the bronchial sensitivity to inhaled methacholine as measured by spirometry. We conclude that subsensitivity is a characteristic response in most tissues to chronic exogenous adrenergic stimulation. The failure to demonstrate altered methacholine sensitivity may indicate that the adrenergic receptors of the bronchial smooth muscles are an exception to this rule, or, more likely, may reflect the difficulty in demonstrating partial bronchial adrenergic blockade in normal individuals.