YIA Abstracts: Best Abstracts on Clinical Studies

Veltmann C, Schimpf R, Steitner F, Hu D, Pfeiffer R, Borggrefe M, Wolpert C, Antzelevitch C. Electrocardiographic identification of SCN5A mutation carriers in a large European family. Europace Journal 2009, 11(Supplement 2), Abstract 34.Wijnmaalen AP, Van Der Geest RJ, Siebelink HJ, Kroft L, Bax JJ, Reiber JH, Schalij MJ, Zeppenfeld K. Integration of MRI derived 3D scar maps with electroanatomical mapping during catheter ablation of scar-related ventricular tachycardia late after myocardial infarction. Europace Journal 2009, 11(Supplement 2), Abstract 35.Algalarrondo VA, Dinanian SD, Juin CJ, Adams DA, Slama MS. Paroxystic AV block and prophylactic pacing in familial amyloid polyneuropathy. Europace Journal 2009, 11(Supplement 2), Abstract 36.# Electrocardiographic identification of SCN5A mutation carriers in a large European family {#article-title-2} Veltmann C, Schimpf R, Steitner F, Hu D, Pfeiffer R, Borggrefe M, Wolpert C, Antzelevitch C. Electrocardiographic identification of SCN5A mutation carriers in a large European family. Europace Journal 2009, 11(Supplement 2), Abstract 34.Wijnmaalen AP, Van Der Geest RJ, Siebelink HJ, Kroft L, Bax JJ, Reiber JH, Schalij MJ, Zeppenfeld K. Integration of MRI derived 3D scar maps with electroanatomical mapping during catheter ablation of scar-related ventricular tachycardia late after myocardial infarction. Europace Journal 2009, 11(Supplement 2), Abstract 35.Algalarrondo VA, Dinanian SD, Juin CJ, Adams DA, Slama MS. Paroxystic AV block and prophylactic pacing in familial amyloid polyneuropathy. Europace Journal 2009, 11(Supplement 2), Abstract 36.The loss-of-function SCN5A missense mutation E1784K leads to the Brugada and/or Long QT phenotype and to cardiac conduction disease. The aim of the present study was to perform a genotype-phenotype correlation in a large family with the E1784K mutation and to identify electrocardiographic markers capable of differentiating between mutation carriers and non-carriers. Methods: We screened a large 33-member European family. The work-up included the medical and family history (n=33), a baseline ECG (n=27), sodium blocker challenge (n=23) and genetic screening (n=27). Results: 27 members (28±15 years of age; 16 males, 11 females) were genotyped. In 17 of 27 patients (8 males, 9 females) a E1784K missense mutation was identified in SCN5A. Mutation carriers revealed significantly longer PR and QT intervals and QRS duration compared to non-carriers. (PQ: 195ms vs. 155ms, P<0.003; QT: 466ms vs. 415ms, P<0.0001, QRS: 100ms vs. 80ms; P<0.002). Using ROC analysis, QTc ≥ 445 ms was identified as a good predictor of a positive genotype (sensitivity 88%, specificity 100%). No patient showed a spontaneous Brugada type I ECG. 4 patients displayed a Brugada type II and III ECG. Out of 23 ajmaline tests 12 were positive, 8 negative und 3 were prematurely terminated due to QRS prolongation and premature ventricular contractions. All non-carriers revealed a negative ajmaline test (n=8). In 15 of 17 patients with positive genotype, ajmaline challenge was performed. 12 tests (80%) were positive and 3 tests were prematurely terminated. Conclusions: Our results indicate E1784K-SCN5A carriers have significantly longer PR, QT and QRS durations. 80% of mutation carriers and none of non-carriers display a Type I ST segment elevation characteristic of Brugada syndrome following challenge with sodium channel blockers. QTc interval ≥ 445 predicted the presence of the E1784K mutation. All non-carriers displayed normal ECG parameters. # Integration of MRI derived 3D scar maps with electroanatomical mapping during catheter ablation of scar-related ventricular tachycardia late after myocardial infarction {#article-title-3} Veltmann C, Schimpf R, Steitner F, Hu D, Pfeiffer R, Borggrefe M, Wolpert C, Antzelevitch C. Electrocardiographic identification of SCN5A mutation carriers in a large European family. Europace Journal 2009, 11(Supplement 2), Abstract 34.Wijnmaalen AP, Van Der Geest RJ, Siebelink HJ, Kroft L, Bax JJ, Reiber JH, Schalij MJ, Zeppenfeld K. Integration of MRI derived 3D scar maps with electroanatomical mapping during catheter ablation of scar-related ventricular tachycardia late after myocardial infarction. Europace Journal 2009, 11(Supplement 2), Abstract 35.Algalarrondo VA, Dinanian SD, Juin CJ, Adams DA, Slama MS. Paroxystic AV block and prophylactic pacing in familial amyloid polyneuropathy. Europace Journal 2009, 11(Supplement 2), Abstract 36.Background: The current used gold standard to guide substrate based ablation of scar-related ventricular tachycardia (VT) relies on electroanatomical endocardial and epicardial voltage mapping (EAM). Integration of the complex 3-dimensional (3D) scar geometry derived from contrast enhanced magnetic resonance imaging (CE-MRI) with EAM may provide supplementary substrate information. This study aimed to assess the feasibility of integrating CE-MRI derived data with EAM during radiofrequency catheter ablation (RFCA) of scar-related VT. Methods: 15 patients (14 male, 64±9yr) referred for RFCA of VT late after myocardial infarction underwent CE-MRI using a 1.5 T MRI system. Endocardial and epicardial contours of the CE-MRI were used to create 3D surface meshes of the left ventricle (LV), the aortic cusps and the left main (LM) origin. The vertices of the meshes were color coded based on the transmural extend of scar at a particular intramural location. Prior to ablation the MRI derived scar maps were imported into the CARTO-merge system. Bipolar endocardial EAM of the LV and aortic cusps were obtained and the LM location was marked. Areas with bipolar electrograms <1.5mV were defined as scar. Registration of the MRI derived scar maps and electroanatomical voltage maps was performed using the LM as landmark and the CARTO surface registration algorithm. Results: The average number of LV EAM points was 258±42. Merging of MRI derived scar data with voltage maps was successful in all patients with an average registration error of 3.8±0.6mm. There was a good agreement between regions of transmural scar defined by MRI and EAM. In 5 (33%) patients the subendocardial scar area identified by CE-MRI was larger than the scar area defined by EAM. Conclusions: Integration of MRI derived scar maps with EAM during VT ablation is feasible and accurate. CE-MRI derived scar maps identify intramural scar undetected by EAM and may provide important supplementary substrate information. # Paroxystic AV block and prophylactic pacing in familial amyloid polyneuropathy {#article-title-4} Veltmann C, Schimpf R, Steitner F, Hu D, Pfeiffer R, Borggrefe M, Wolpert C, Antzelevitch C. Electrocardiographic identification of SCN5A mutation carriers in a large European family. Europace Journal 2009, 11(Supplement 2), Abstract 34.Wijnmaalen AP, Van Der Geest RJ, Siebelink HJ, Kroft L, Bax JJ, Reiber JH, Schalij MJ, Zeppenfeld K. Integration of MRI derived 3D scar maps with electroanatomical mapping during catheter ablation of scar-related ventricular tachycardia late after myocardial infarction. Europace Journal 2009, 11(Supplement 2), Abstract 35.Algalarrondo VA, Dinanian SD, Juin CJ, Adams DA, Slama MS. Paroxystic AV block and prophylactic pacing in familial amyloid polyneuropathy. Europace Journal 2009, 11(Supplement 2), Abstract 36.Introduction: Familial amyloid polyneuropathy (FAP) is a dominantly inherited disease caused by mutated transthyretin. FAP cardiopathy is characterized by conduction disorders, denervation, and hypertrophic cardiomyopathy. Because of the risk of high degree atrioventricular (AV) block, prophylactic pacing can be suggested for high risk patients: in case of infra nodal AV block (HV interval > 70ms or between 60ms and 70ms with ECG abnormalities) or in case of unexplained syncope. By using pacing systems wich preserve physiological AV conduction, our purpose was to estimate prevalence of AV block and pacing dependance for high risk FAP patients. Methods: In a cohort of 29 FAP patients with conduction disorders leading to prophylactic pacing, we studied AV conduction using the AAI Safe R system (ELA medical). Datas were collected by using the Holter memories of pacemakers. Results: Patients were 50±15 years old and were followed during 13.7±11.9 months after pace maker insertion (12080 days cumulated). Before pace maker insertion, ECG was normal in 23% of cases. Electrophysiologic study showed 118±12ms for AH interval and 62±6ms for HV interval. Average percentage of ventricular pacing was 15±25%and 31±34% for atrial pacing. If 58% of patients (17/29) had less than 5% needs of ventricular pacing, we noted AV blocks episods for all patients but three (90%). Frequency of AV conduction disorders was 356±514 events per month (epm) and was distributed in 17±56 epm for type III AV block, 288±483 epm for type II AV block, 39±61epm for type I AV block and 1±4 for pauses. Percentage of ventricular pacing was positively correlated to frequency of AV block (R = 0.9, P<0.0001), to AH interval (R = 0.7, P = 0.003) and negatively to HV interval (R = -0.63, P = 0.007). During the study, sustained atrial arrhythmias occurred in two patients. No sustained ventricular arrhythmias were noted. Conclusion: Patients with FAP cardiopathy can present unpredictable paroxystic high degrees AV blocks. For patients with high risk of conduction disorders (HV interval >70ms, HV interval between 60ms and 70ms with ECG abnormalities or in case of unexplained syncope), prophylactic pacemaker insertion should be performed. Pacemaker features designed to promote spontaneous atrioventricular conduction allow a good AV conduction monitoring in FAP patients. Pre operative impairment of the nodal conduction is correlated to the rate of ventricular pacing with this stimulation mode.