- Email: [email protected]
B-type natriuretic peptide reduction after electrical cardioversion of persistent atrial fibrillation
S226
Heart Rhythm, Vol 2, No 5, May Supplement 2005
and Martin J. Schalij, MD, PhD. Leiden University Medical Center, Leiden, Netherlands. Introduction: Diagnosis of arrhythmogenic right ventricular dysplasia / cardiomyopathy (ARVD/C) has major implications for the management of patients and their first-degree relatives. Diagnosis may be difficult and is based on a set of criteria proposed by the International Task Force (TF) for Cardiomyopathies in 1994. More recently, diagnostic criteria based on MRI or ECG only have been suggested in the literature. We evaluated the consistency in outcome between 3 different sets of diagnostic criteria. Methods and Results: A total of 52 patients (33 male, mean age 46⫾11 yrs) were evaluated for the possible occurrence of ARVD. Patients were evaluated because of ventricular arrhythmias (16), palpitations/ (pre) syncope (31), ECG changes during routine analysis (4) or a family history of ARVD (1). All patients were analysed based on the TF-, MRI- and ECG criteria and their concordance was calculated. According to the TF-criteria 27 (52%) patients were diagnosed with ARVD. MRI was performed in 45 (86%) patients (7 patients were excluded because of prior ICD implant) of whom 20 (45%) were diagnosed with ARVD. Twenty patients (39%) fulfilled the ECG criteria for ARVD. A moderate concordance was found between diagnoses based on the TF- and the MRI criteria (kappa ⫽ 0.49) and a fair concordance was found between the TF- and the ECG-criteria (kappa⫽0.25). On the contrary we found only a slight concordance between the MRI-and ECG diagnoses (kappa⫽0.08). Conclusion: These results indicate that there is not a strong concordance between the 3 diagnostic sets. Therefore we conclude that the clinical diagnosis of ARVD has to be based on TF-criteria, and cannot be replaced by a single diagnostic technique. P4-37 ASSESSMENT OF RIGHT VENTRICULAR FUNCTION BY THREE DIMENSIONAL ECHOCARDIOGRAPHY IN ARRHYTHMOGENIC RIGHT VENTRICULAR DYSPLASIA Kalpana R. Prakasa, MD, Chandra Bomma, MD, Darshan Dalal, MD, MPH, Cynthia James, PhD, Crystal Tichnell, Jianwen Wang, MD, Mary Corretti, MD, Hugh Calkins, MD and Theodore Abraham, MD. Johns Hopkins University School of Medicine, Baltimore, MD. Background: Arrhythmogenic right ventricular dysplasia (ARVD) is characterized by progressive complex right ventricular (RV) remodeling and dysfunction. Three-dimensional echocardiography (3DE) is not well studied in the functional assessment of RV. The objectives of our study were to study the morphology and function of RV in ARVD using 3DE and to assess if the inter and intra observer variability of 3DE is clinically acceptable. Methods: We prospectively performed 3DE in 15 patients with ARVD and 15 controls. ARVD was diagnosed using Task Force criteria. Atleast three views were obtained minutes apart to facilitate determination of intra observer variability. 3DE data were analyzed off-line by two blinded, independent observers using Tom Tec software. Results: ARVD and controls were matched for age and proportion of males (33⫾13 years, 8 men). RV end systolic volume (44⫾14 ml versus 30⫾7 ml, p ⫽ 0.002) and ejection fraction (47⫾6 ml versus 55⫾5 ml, p⫽0.0003) were significantly different between ARVD patients and controls, respectively. There was no significant difference in RV end diastolic volume (84⫾29 ml versus 69⫾19 ml, p⫽0.09) between the ARVD and controls, respectively. Intra (r⫽0.95) and inter-observer (r⫽0.66) correlation was good. One potential limitation of the study was to image a severely dilated RV. It was overcome by increasing the the 3D sector size and by moving the transducer to selectively include the RV in the image sector. Conclusions: 3DE detected the RV dysfunction in ARVD patients compared to controls. High intra and inter-observer correlation suggests that 3DE may be useful in follow-up of ARVD patients. The following figure demonstrates the close correlation between the intra-observer measurements.
P4-38 COMPARISON OF MONITORING USING NASAL-CANNULA FLOW-SIGNAL ASSOCIATED WITH AN EKG HOLTER TO FULL POLYSOMNOGRAPHY IN SLEEP DISORDERED BREATHING *Jean-Louis Pe´pin, MD, *Pascal Defaye, MD, *Elodie Vincent, MS, *Yann Poezevara, MS and *Patrick Le´vy, MD. Sleep laboratory, University hospital, Grenoble, France, University Hospital, Grenoble, France and ELA Medical, Le Plessis-Robinson, France. The present study aimed to assess the performance of a Holter recorder featuring nasal pressure (NP) and EKG for diagnosis of Sleep-Disordered Breathing (SDB) Methods: 30 patients suspected for presenting SDB underwent a polysomnography (PSG) with concomitant EKG and NP recordings. The Holter recordings were visually scored for apneas and hyperpnoeas by a blinded expert. The Apnea /Hypopnea Index (AHI) is compared to the PSG results and then matched with the automatic analysis given by the Holter system. Results: The AHI calculated with the visually scored recordings was closely and linearly related with the AHI of PSG (r2⫽0.933). The AHI was significantly lower using the PSG than the visual scoring of NP (Bland and Altman plot: mean difference 5.8/h). We obtained a specificity of 93.7% and a sensitivity of 100% to discriminate patients with SDB (AHI threshold 20.8 obtained through ROC curve analysis). The AHI calculated with the Holter automatic analysis was closely and linearly related with the AHI of the visual scoring of NP (r2⫽0.729). We obtained specificity and a sensitivity of 72.7% to discriminate patients with SDB, with a threshold equal to 20 (ROC curve analysis). The AHI calculated with the Holter automatic analysis was closely and linearly related with the AHI of PSG (r2⫽0.67). We obtained a specificity of 100% and a sensitivity of 66.7% for discrimination (ROC curve analysis). The diagnosis capability from the automatic analysis was excellent (specificity and sensitivity ⫽ 100%) for AHI ⬍15 and ⬎35. Conclusion: Nasal pressure recording and analysis through an automatic Holter system is an efficient and easy-to-use tool to diagnose sleepdisordered breathing. P4-39 B-TYPE NATRIURETIC PEPTIDE REDUCTION AFTER ELECTRICAL CARDIOVERSION OF PERSISTENT ATRIAL FIBRILLATION *Federico Lombardi, MD, Sebastiano Belletti, MD, Fabrizio Tundo, MD and Wanda Porreca, MD. Osp. San Paolo, Universita` di Milano, Milan, Italy and Laboratorio Analisi, Osp. San Paolo, Universita` di Milano, Milan, Italy. Stretch of atrial myocites and altered ventricular filling pattern associated with atrial fibrillation (AF) may represent an adequate stimulus for B-type natriuretic peptide (BNP) elevation. We therefore evaluated whether recovery of sinus rhythm and normalization of atrial function could affect BNP values. Methods: We measured with an electrochemiluminescent assay NT-proBNP in 27 patients (aged 67⫾7 years; mean SD) with preserved left ventricular ejection fraction (LVEF; 61⫾ 6%), who underwent electrical cardioversion (CV) for persistent AF. Transesophageal echocardiography was performed in all patients to exclude atrial thrombosis and to measure left atrial appendage emptying. NT-proBNP plasma concentrations were determined immediately before and three weeks after CV.
Poster 4 Results: Electrical cardioversion was successful in all 27 subjects. In spite of normal LVEF, NT-proBNP values before CV were above the reference normal values (⬍280 pg/ml) in all but one patient. Nine patients (33%) had an early atrial fibrillation recurrence (within 3 weeks). Persistence of sinus rhythm was associated with a significant reduction in NT-proBNP values (from 672⫾280 to 337⫾230 pg/ml; p⫽ 0.001). No significant differences were instead observed in the subjects with an early recurrence . No correlation was found between NT-proBNP values and, respectively, duration of AF, ejection fraction, left atrial diameter and HRV parameters. A strong correlation was found instead with left appendage emptying velocity (r⫽-0.73; p⫽0.001). Conclusions: These data indicate that in patients with persistent AF, abnormal atrial dynamics are strongly associated with NT-proBNP levels. Recovery of sinus rhythm is accompanied by a rapid reduction of NTproBNP values likely to be due to the restoration of a more physiological hemodynamic function in the atria.
P4-40 P-WAVE REMODELING MEASURED WITH MAGNETOCARDIOGRAPHY IN PAROXYSMAL AND PERSISTENT ATRIAL FIBRILLATION Mika Lehto, MD, Raija Koskinen, MD, Ville Ma¨ntynen, MS, Jouni Kuusisto, Med, Juha Montonen, PhD, Liisa-Maria Voipio-Pulkki, MD, PhD, Mika Laine, MD, PhD and Lauri Toivonen, MD. Helsinki University Hospital, Helsinki, Finland, Helsinki University of Technology, Helsinki, Finland and BioMag Laboratory, Helsinki University Hospital, Helsinki, Finland. Aim: The aim of this study was to study atrial electrophysiological remodeling by using high resolution magnetocardiography (MCG) and signal averaged ECG (SAECG) in patients with paroxysmal and persistent atrial fibrillation (AF). Methods: One hundred and four healthy controls (35⫾15 years), 51 patients with paroxysmal AF (PAF) (47⫾10 years) and 26 patients with persistent AF (CAF) (58⫾12 years, AF duration 84⫾61 days before cardioversion) underwent multichannel MCG recording in our institution. During sinus rhythm, a 33-channel MCG over the anterior chest and orthogonal 3-lead SAECG were simultaneously recorded in a magnetically shielded room. Signal averaged and filtered (40Hz) atrial signal duration (Pd), obtained with automatic detection of onset and offset, and fragmentation of p-wave determined as fragmentation score (S) were measured. P-wave in MCG was assessed as spatial magnitude of all MCG channels with acceptable signal-to-noise ratio, and in SAECG as vector magnitude of XYZ-channels. Dispersion of Pd was determined as standard deviation (SD) of Pd in included MCG channels and in SAECG as SD of XYZ-channels.
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p⬍0.001 between controls and PAF, 2p⬍0.001 between PAF and CAF, p⬍0.001 between controls and CAF, 4p⬍0.05 between controls and PAF. 5 p⬍0.01 between PAF and CAF, 6p⬍0.01 between controls and CAF. 3
S227 Conclusions: Atrial fibrillation was associated with a progressive prolongation of the p-wave duration and an increase in p-wave dispersion. We suggest that these changes in p-wave temporal parameters reflect either progression of the underlying degenerative process in the atria or electrical remodeling of atrial myocardium in response to prolonged tachycardia. P4-41 THREE DIMENSIONAL CT- SCAN TO IDENTIFY THE ANATOMICAL RELATION BETWEEN THE POSTERIOR LEFT ATRIAL WALL AND THE ESOPHAGUS Marian Andronache, MD, S. Tissier, MD, †C. De Chillou, Md Phd, †A. Codreanu, †I-Magnin Poull, †A. Abdelaal, †Y. Ernst, †S. State, †V. Laurent, †D. Regent and †E. Aliot. CHU Nancy, Vandoeuvre les Nancy, France and CHU Nancy, France. Electrical isolation of the pulmonary veins (PV) using radiofrequency (RF) ablation has been shown an interesting technique to cure paroxysmal or persistent atrial fibrillation (AF). Atrio-esophageal fistula (AEF) has recently been recognized as a serious, life-threatening, adverse event following surgical or endocardial RF ablation of AF. Pre-procedural three dimensional (3D)-imaging using computed tomographic scan (CT-scan) could help identifying the precise relationship between the esophagus (E) and the posterior left atrial (LA) wall to avoid RF applications along the esophagus course. Such an anatomical evaluation was the aim of the present study. Methods and Results: A 3D LA imaging using a CT-scan was obtained in 23 patients (pts) before an RF ablation procedure for a paroxysmal (n⫽14, group A) or persistent (n⫽9, group B) AF. The following parameters were measured in all patients (mean values, mm): distance between superior and inferior PV ostia: superior line (SL A ⫽ 46.2, SL B⫽49.2) and inferior line (IL A ⫽ 45.9, IL B ⫽ 49.3), diameter of E (DE A ⫽ 21.5, DE B⫽18.9), rapport between SL and IL with E (SL A/E⫽46.6%, SL B/E⫽38.5%, IL A/E⫽46.9%, IL B/E⫽38.3%), distance from each PV ostia and ipsilateral border of E: right superior (RS) PV-E ⫽14.8 (A), RSPV-E⫽18.2 (B), right inferior (RI) PV-E ⫽13.9 (A), RIPV-E⫽17.2 (B), left superior (LS) PV-E ⫽7.7 (A), LSPV-E ⫽ 4.4 (B), left inferior (LI) PV-E ⫽16.0 (A), LIPVE⫽6.2 (B), and mean LA volume (V): V A⫽103.8 cc, V B⫽ 136.1 cc The mean parietal posterior atrial thickness regarding the E. was 1.9 mm (group A) and 2.5 mm (group B) No significant differences was observed between 2 groups. A thin fat layer located between the posterior LA wall and E was observed in 6 pts (26%) The following patterns of esophagus was observed: left vertical (closer to the LSPV and LIPV) -15 pts (65,2%), right vertical (closer to the RSPV and RIPV)- 5 pts (21,7%) and left oblique (closer to the LSPV and RIPV)-3 pts (13,0%) Conclusions: The anatomical data assessed by CT scan are very important to define the comprehensive relation between the esophagus and posterior LA wall to guide the AF ablation approach in order to minimize the risk of AEF P4-42 INCIDENCE OF PULMONARY VEIN STENOSIS AFTER PULMONARY VEIN ISOLATION BY USE OF CRYOENERGY IN PATIENTS WITH THERAPY-REFRACTORY ATRIAL FIBRILLATION IN THE LONG-TERM COURSE Harald Greiss, MD, Malte Kuniss, MD, Klaus Kurzidim, MD, Sergey Zaltsberg, MD, Hans-Ju¨rgen Schneider, MD, Jochen Hansel, MD, Thorsten Dill, MD, Alexander Berkowitsch, PhD, Johannes Sperzel, MD and Heinz-Friedrich Pitschner, MD. Kerckhoff-Clinic, Bad Nauheim, Germany and KerckoffClinic, Bad Nauheim, Germany. Introduction: Pulmonary vein stenosis (PVS) is a possible severe complication after pulmonary vein isolation (PVI) with radiofrequency energy (RF) was known to have a complication rate of 1-13% in the last 4 years. Cryoenergy ablation (CA) as alternative for treatment for PVI might reduce this risk which was examined in a prospective trial. Methods: 54 patients (age: x⫽54.9 ⫾ 9.6, 32 m) with Afib underwent PVI
Heart Rhythm, Vol 2, No 5, May Supplement 2005
and Martin J. Schalij, MD, PhD. Leiden University Medical Center, Leiden, Netherlands. Introduction: Diagnosis of arrhythmogenic right ventricular dysplasia / cardiomyopathy (ARVD/C) has major implications for the management of patients and their first-degree relatives. Diagnosis may be difficult and is based on a set of criteria proposed by the International Task Force (TF) for Cardiomyopathies in 1994. More recently, diagnostic criteria based on MRI or ECG only have been suggested in the literature. We evaluated the consistency in outcome between 3 different sets of diagnostic criteria. Methods and Results: A total of 52 patients (33 male, mean age 46⫾11 yrs) were evaluated for the possible occurrence of ARVD. Patients were evaluated because of ventricular arrhythmias (16), palpitations/ (pre) syncope (31), ECG changes during routine analysis (4) or a family history of ARVD (1). All patients were analysed based on the TF-, MRI- and ECG criteria and their concordance was calculated. According to the TF-criteria 27 (52%) patients were diagnosed with ARVD. MRI was performed in 45 (86%) patients (7 patients were excluded because of prior ICD implant) of whom 20 (45%) were diagnosed with ARVD. Twenty patients (39%) fulfilled the ECG criteria for ARVD. A moderate concordance was found between diagnoses based on the TF- and the MRI criteria (kappa ⫽ 0.49) and a fair concordance was found between the TF- and the ECG-criteria (kappa⫽0.25). On the contrary we found only a slight concordance between the MRI-and ECG diagnoses (kappa⫽0.08). Conclusion: These results indicate that there is not a strong concordance between the 3 diagnostic sets. Therefore we conclude that the clinical diagnosis of ARVD has to be based on TF-criteria, and cannot be replaced by a single diagnostic technique. P4-37 ASSESSMENT OF RIGHT VENTRICULAR FUNCTION BY THREE DIMENSIONAL ECHOCARDIOGRAPHY IN ARRHYTHMOGENIC RIGHT VENTRICULAR DYSPLASIA Kalpana R. Prakasa, MD, Chandra Bomma, MD, Darshan Dalal, MD, MPH, Cynthia James, PhD, Crystal Tichnell, Jianwen Wang, MD, Mary Corretti, MD, Hugh Calkins, MD and Theodore Abraham, MD. Johns Hopkins University School of Medicine, Baltimore, MD. Background: Arrhythmogenic right ventricular dysplasia (ARVD) is characterized by progressive complex right ventricular (RV) remodeling and dysfunction. Three-dimensional echocardiography (3DE) is not well studied in the functional assessment of RV. The objectives of our study were to study the morphology and function of RV in ARVD using 3DE and to assess if the inter and intra observer variability of 3DE is clinically acceptable. Methods: We prospectively performed 3DE in 15 patients with ARVD and 15 controls. ARVD was diagnosed using Task Force criteria. Atleast three views were obtained minutes apart to facilitate determination of intra observer variability. 3DE data were analyzed off-line by two blinded, independent observers using Tom Tec software. Results: ARVD and controls were matched for age and proportion of males (33⫾13 years, 8 men). RV end systolic volume (44⫾14 ml versus 30⫾7 ml, p ⫽ 0.002) and ejection fraction (47⫾6 ml versus 55⫾5 ml, p⫽0.0003) were significantly different between ARVD patients and controls, respectively. There was no significant difference in RV end diastolic volume (84⫾29 ml versus 69⫾19 ml, p⫽0.09) between the ARVD and controls, respectively. Intra (r⫽0.95) and inter-observer (r⫽0.66) correlation was good. One potential limitation of the study was to image a severely dilated RV. It was overcome by increasing the the 3D sector size and by moving the transducer to selectively include the RV in the image sector. Conclusions: 3DE detected the RV dysfunction in ARVD patients compared to controls. High intra and inter-observer correlation suggests that 3DE may be useful in follow-up of ARVD patients. The following figure demonstrates the close correlation between the intra-observer measurements.
P4-38 COMPARISON OF MONITORING USING NASAL-CANNULA FLOW-SIGNAL ASSOCIATED WITH AN EKG HOLTER TO FULL POLYSOMNOGRAPHY IN SLEEP DISORDERED BREATHING *Jean-Louis Pe´pin, MD, *Pascal Defaye, MD, *Elodie Vincent, MS, *Yann Poezevara, MS and *Patrick Le´vy, MD. Sleep laboratory, University hospital, Grenoble, France, University Hospital, Grenoble, France and ELA Medical, Le Plessis-Robinson, France. The present study aimed to assess the performance of a Holter recorder featuring nasal pressure (NP) and EKG for diagnosis of Sleep-Disordered Breathing (SDB) Methods: 30 patients suspected for presenting SDB underwent a polysomnography (PSG) with concomitant EKG and NP recordings. The Holter recordings were visually scored for apneas and hyperpnoeas by a blinded expert. The Apnea /Hypopnea Index (AHI) is compared to the PSG results and then matched with the automatic analysis given by the Holter system. Results: The AHI calculated with the visually scored recordings was closely and linearly related with the AHI of PSG (r2⫽0.933). The AHI was significantly lower using the PSG than the visual scoring of NP (Bland and Altman plot: mean difference 5.8/h). We obtained a specificity of 93.7% and a sensitivity of 100% to discriminate patients with SDB (AHI threshold 20.8 obtained through ROC curve analysis). The AHI calculated with the Holter automatic analysis was closely and linearly related with the AHI of the visual scoring of NP (r2⫽0.729). We obtained specificity and a sensitivity of 72.7% to discriminate patients with SDB, with a threshold equal to 20 (ROC curve analysis). The AHI calculated with the Holter automatic analysis was closely and linearly related with the AHI of PSG (r2⫽0.67). We obtained a specificity of 100% and a sensitivity of 66.7% for discrimination (ROC curve analysis). The diagnosis capability from the automatic analysis was excellent (specificity and sensitivity ⫽ 100%) for AHI ⬍15 and ⬎35. Conclusion: Nasal pressure recording and analysis through an automatic Holter system is an efficient and easy-to-use tool to diagnose sleepdisordered breathing. P4-39 B-TYPE NATRIURETIC PEPTIDE REDUCTION AFTER ELECTRICAL CARDIOVERSION OF PERSISTENT ATRIAL FIBRILLATION *Federico Lombardi, MD, Sebastiano Belletti, MD, Fabrizio Tundo, MD and Wanda Porreca, MD. Osp. San Paolo, Universita` di Milano, Milan, Italy and Laboratorio Analisi, Osp. San Paolo, Universita` di Milano, Milan, Italy. Stretch of atrial myocites and altered ventricular filling pattern associated with atrial fibrillation (AF) may represent an adequate stimulus for B-type natriuretic peptide (BNP) elevation. We therefore evaluated whether recovery of sinus rhythm and normalization of atrial function could affect BNP values. Methods: We measured with an electrochemiluminescent assay NT-proBNP in 27 patients (aged 67⫾7 years; mean SD) with preserved left ventricular ejection fraction (LVEF; 61⫾ 6%), who underwent electrical cardioversion (CV) for persistent AF. Transesophageal echocardiography was performed in all patients to exclude atrial thrombosis and to measure left atrial appendage emptying. NT-proBNP plasma concentrations were determined immediately before and three weeks after CV.
Poster 4 Results: Electrical cardioversion was successful in all 27 subjects. In spite of normal LVEF, NT-proBNP values before CV were above the reference normal values (⬍280 pg/ml) in all but one patient. Nine patients (33%) had an early atrial fibrillation recurrence (within 3 weeks). Persistence of sinus rhythm was associated with a significant reduction in NT-proBNP values (from 672⫾280 to 337⫾230 pg/ml; p⫽ 0.001). No significant differences were instead observed in the subjects with an early recurrence . No correlation was found between NT-proBNP values and, respectively, duration of AF, ejection fraction, left atrial diameter and HRV parameters. A strong correlation was found instead with left appendage emptying velocity (r⫽-0.73; p⫽0.001). Conclusions: These data indicate that in patients with persistent AF, abnormal atrial dynamics are strongly associated with NT-proBNP levels. Recovery of sinus rhythm is accompanied by a rapid reduction of NTproBNP values likely to be due to the restoration of a more physiological hemodynamic function in the atria.
P4-40 P-WAVE REMODELING MEASURED WITH MAGNETOCARDIOGRAPHY IN PAROXYSMAL AND PERSISTENT ATRIAL FIBRILLATION Mika Lehto, MD, Raija Koskinen, MD, Ville Ma¨ntynen, MS, Jouni Kuusisto, Med, Juha Montonen, PhD, Liisa-Maria Voipio-Pulkki, MD, PhD, Mika Laine, MD, PhD and Lauri Toivonen, MD. Helsinki University Hospital, Helsinki, Finland, Helsinki University of Technology, Helsinki, Finland and BioMag Laboratory, Helsinki University Hospital, Helsinki, Finland. Aim: The aim of this study was to study atrial electrophysiological remodeling by using high resolution magnetocardiography (MCG) and signal averaged ECG (SAECG) in patients with paroxysmal and persistent atrial fibrillation (AF). Methods: One hundred and four healthy controls (35⫾15 years), 51 patients with paroxysmal AF (PAF) (47⫾10 years) and 26 patients with persistent AF (CAF) (58⫾12 years, AF duration 84⫾61 days before cardioversion) underwent multichannel MCG recording in our institution. During sinus rhythm, a 33-channel MCG over the anterior chest and orthogonal 3-lead SAECG were simultaneously recorded in a magnetically shielded room. Signal averaged and filtered (40Hz) atrial signal duration (Pd), obtained with automatic detection of onset and offset, and fragmentation of p-wave determined as fragmentation score (S) were measured. P-wave in MCG was assessed as spatial magnitude of all MCG channels with acceptable signal-to-noise ratio, and in SAECG as vector magnitude of XYZ-channels. Dispersion of Pd was determined as standard deviation (SD) of Pd in included MCG channels and in SAECG as SD of XYZ-channels.
1
p⬍0.001 between controls and PAF, 2p⬍0.001 between PAF and CAF, p⬍0.001 between controls and CAF, 4p⬍0.05 between controls and PAF. 5 p⬍0.01 between PAF and CAF, 6p⬍0.01 between controls and CAF. 3
S227 Conclusions: Atrial fibrillation was associated with a progressive prolongation of the p-wave duration and an increase in p-wave dispersion. We suggest that these changes in p-wave temporal parameters reflect either progression of the underlying degenerative process in the atria or electrical remodeling of atrial myocardium in response to prolonged tachycardia. P4-41 THREE DIMENSIONAL CT- SCAN TO IDENTIFY THE ANATOMICAL RELATION BETWEEN THE POSTERIOR LEFT ATRIAL WALL AND THE ESOPHAGUS Marian Andronache, MD, S. Tissier, MD, †C. De Chillou, Md Phd, †A. Codreanu, †I-Magnin Poull, †A. Abdelaal, †Y. Ernst, †S. State, †V. Laurent, †D. Regent and †E. Aliot. CHU Nancy, Vandoeuvre les Nancy, France and CHU Nancy, France. Electrical isolation of the pulmonary veins (PV) using radiofrequency (RF) ablation has been shown an interesting technique to cure paroxysmal or persistent atrial fibrillation (AF). Atrio-esophageal fistula (AEF) has recently been recognized as a serious, life-threatening, adverse event following surgical or endocardial RF ablation of AF. Pre-procedural three dimensional (3D)-imaging using computed tomographic scan (CT-scan) could help identifying the precise relationship between the esophagus (E) and the posterior left atrial (LA) wall to avoid RF applications along the esophagus course. Such an anatomical evaluation was the aim of the present study. Methods and Results: A 3D LA imaging using a CT-scan was obtained in 23 patients (pts) before an RF ablation procedure for a paroxysmal (n⫽14, group A) or persistent (n⫽9, group B) AF. The following parameters were measured in all patients (mean values, mm): distance between superior and inferior PV ostia: superior line (SL A ⫽ 46.2, SL B⫽49.2) and inferior line (IL A ⫽ 45.9, IL B ⫽ 49.3), diameter of E (DE A ⫽ 21.5, DE B⫽18.9), rapport between SL and IL with E (SL A/E⫽46.6%, SL B/E⫽38.5%, IL A/E⫽46.9%, IL B/E⫽38.3%), distance from each PV ostia and ipsilateral border of E: right superior (RS) PV-E ⫽14.8 (A), RSPV-E⫽18.2 (B), right inferior (RI) PV-E ⫽13.9 (A), RIPV-E⫽17.2 (B), left superior (LS) PV-E ⫽7.7 (A), LSPV-E ⫽ 4.4 (B), left inferior (LI) PV-E ⫽16.0 (A), LIPVE⫽6.2 (B), and mean LA volume (V): V A⫽103.8 cc, V B⫽ 136.1 cc The mean parietal posterior atrial thickness regarding the E. was 1.9 mm (group A) and 2.5 mm (group B) No significant differences was observed between 2 groups. A thin fat layer located between the posterior LA wall and E was observed in 6 pts (26%) The following patterns of esophagus was observed: left vertical (closer to the LSPV and LIPV) -15 pts (65,2%), right vertical (closer to the RSPV and RIPV)- 5 pts (21,7%) and left oblique (closer to the LSPV and RIPV)-3 pts (13,0%) Conclusions: The anatomical data assessed by CT scan are very important to define the comprehensive relation between the esophagus and posterior LA wall to guide the AF ablation approach in order to minimize the risk of AEF P4-42 INCIDENCE OF PULMONARY VEIN STENOSIS AFTER PULMONARY VEIN ISOLATION BY USE OF CRYOENERGY IN PATIENTS WITH THERAPY-REFRACTORY ATRIAL FIBRILLATION IN THE LONG-TERM COURSE Harald Greiss, MD, Malte Kuniss, MD, Klaus Kurzidim, MD, Sergey Zaltsberg, MD, Hans-Ju¨rgen Schneider, MD, Jochen Hansel, MD, Thorsten Dill, MD, Alexander Berkowitsch, PhD, Johannes Sperzel, MD and Heinz-Friedrich Pitschner, MD. Kerckhoff-Clinic, Bad Nauheim, Germany and KerckoffClinic, Bad Nauheim, Germany. Introduction: Pulmonary vein stenosis (PVS) is a possible severe complication after pulmonary vein isolation (PVI) with radiofrequency energy (RF) was known to have a complication rate of 1-13% in the last 4 years. Cryoenergy ablation (CA) as alternative for treatment for PVI might reduce this risk which was examined in a prospective trial. Methods: 54 patients (age: x⫽54.9 ⫾ 9.6, 32 m) with Afib underwent PVI