Electroanatomical voltage mapping with contact force sensing for diagnosis of arrhythmogenic right ventricular cardiomyopathy

Background Three-dimensional electroanatomical mapping (EAM) can be helpful to diagnose arrhythmogenic right ventricular cardiomyopathy (ARVC). Yet, previous studies utilizing EAM have not systematically used contact-force sensing catheters (CFSC) to characterize the substrate in ARVC, which is the current gold standard to assure adequate tissue contact. Objective To investigate reference values for endocardial right ventricular (RV) EAM as well as substrate characterization in patients with ARVC by using CFSC. Methods Endocardial RV EAM during sinus rhythm was performed with CFSC in 12 patients with definite ARVC and 5 matched controls without structural heart disease. A subanalysis for the RV outflow tract (RVOT), septum, free-wall, subtricuspid region, and apex was performed. Endocardial bipolar and unipolar voltage amplitudes (BVA, UVA), signal characteristics and duration as well as the impact of catheter orientation on endocardial signals were also investigated. Results ARVC patients showed lower BVA vs. controls (p = 0.018), particularly in the subtricuspid region (1.4, IQR:0.5–3.1 vs. 3.8, IQR:2.5-5 mV, p = 0.037) and RV apex (2.5, IQR:1.5–4 vs. 4.3,IQR:2.9–6.1 mV, p = 0.019). BVA in all RV regions yielded a high sensitivity and specificity for ARVC diagnosis (AUC 59–78%, p < 0.05 for all), with the highest performance for the subtricuspid region (AUC 78%, 95% CI:0.75–0.81, p < 0.001, negative predictive value 100%). A positive correlation between BVA and an orthogonal catheter orientation (46°-90°:r = 0.106, p < 0.001), and a negative correlation between BVA and EGM duration (r = −0.370, p < 0.001) was found. Conclusions EAM using CFSC validates previous bipolar cut-off values for normal endocardial RV voltage amplitudes. RV voltages are generally lower in ARVC as compared to controls, with the subtricuspid area being commonly affected and having the highest discriminatory power to differentiate between ARVC and healthy controls. Therefore, EAM using CFSC constitutes a promising tool for diagnosis of ARVC

Unmappable ventricular tachycardia after an old myocardial infarction. Long-term results of substrate modification in patients with an implantable cardioverter defibrillator

Purpose The frequent occurrence of ventricular tachycardia can create a serious problem in patients with an implantable cardioverter defibrillator. We assessed the long-term efficacy of catheter-based substrate modification using the voltage mapping technique of infarct-related ventricular tachycardia and recurrent device therapy. Methods The study population consisted of 27 consecutive patients (age 68 +/- 8 years, 25 men, mean left ventricular ejection fraction 31 +/- 9%) with an old myocardial infarction and multiple and/or hemodynamically not tolerated ventricular tachycardia necessitating repeated device therapy. A total of 31 substrate modification procedures were performed using the three-dimensional electroanatomical mapping system. Patients were followed up for a median of 23.5 (interquartile range 6.5-53.2) months before and 37.8 (interquartile range 11.7-71.8) months after ablation. Antiarrhythmic drugs were not changed after the procedure, and were stopped 6 to 9 months after the procedure in patients who did not show ventricular tachycardia recurrence. Results Median ventricular tachycardias were 1.6 (interquartile range 0.7-6.7) per month before and 0.2 (interquartile range 0.00-1.3) per month after ablation (P = 0.006). Nine ventricular fibrillation episodes were registered in seven patients before and two after ablation (P = 0.025). Median antitachycardia pacing decreased from 1.6 (interquartile range 0.01-5.5) per month before to 0.18 (interquartile range 0.00-1.6) per month after ablation (P = 0.069). Median number of shocks decreased from 0.19 (interquartile range 0.04-0.81) per month before to 0.00 (interquartile range 0.00-0.09) per month after ablation (P = 0.001). One patient had a transient ischemic attack during the procedure, and another developed pericarditis. Nine patients died during follow-up, eight patients due to heart failure and one patient during valve surgery. Conclusion Catheter-based substrate modification using voltage mapping results in a long-lasting reduction of cardioverter defibrillator therapy in patients with multiple and/or hemodynamically not tolerated infarct-related ventricular tachyarrhythmia

CME-EKG 61: Ventrikuläre Extrasystolie – Diagnostik und Management

Ventrikuläre Extrasystolen (VES) stellen eine sehr häufige Abweichung von der regulären Erregungsausbreitung des Herzens dar. Je nach Anzahl und Symptomatik des Patienten können diese Extraschläge zu einer deutlichen Verunsicherung und Reduktion der Lebensqualität des Patienten führen. Zudem können VES je nach Komorbiditäten einen relevanten Einfluss auf die kardiale Funktion und die kardiovaskuläre Mortalität haben. Für die Behandlung von VES ist eine korrekte Lokalisation des VES-Ursprungs relevant. Therapeutische Optionen beinhalten medikamentöse und interventionelle Ansätze und unterscheiden sich je nach Ursprung der VES und der Beschwerden des Patienten

Electrocardiographic changes in early recognition of Fabry disease

P-wave duration, PQ-interval and QRS width are shorter and repolarisation dispersion more pronounced in patients with FD compared with heart rate and age-matched controls. The significant shortening of the PQ-interval in FD occurs because of a marked shortening of the P-wave duration, which in itself demonstrated a high sensitivity and specificity for early detection and treatment of this disease

Ventricular mapping during atrial and right ventricular pacing: relation of electrogram parameters to ventricular tachycardia reentry circuits after myocardial infarction

INTRODUCTION: Ventricular tachycardia (VT) late after myocardial infarction is usually due to reentry in the border zone of the infarct area. Identification of critical parts of the VT reentry circuit by catheter mapping without needing to induce VT is a desirable goal for VT ablation. The aim of this study was to develop a model to predict reentry circuit locations based on characteristics of sinus or paced electrograms and pace mapping (PM) recorded from the infarct region. METHODS: Left ventricular electroanatomic mapping with the CARTO mapping system was performed in 16 male patients with recurrent VT late after myocardial infarction. A total of 1072 left ventricular sites were recorded during atrial pacing (AP) and right ventricular pacing (RVP), and the corresponding electrograms were analyzed for their local activation time (LAT), onset (ONS), end (END), duration (DUR), and amplitude (AMP) in each pacing sequence. At 1041 of these sites, PM was performed; the resulting stimulus to QRS intervals (S-QRS) was determined at 931 sites, the remaining 110 sites did not capture. All the obtained parameters were compared with the location of 18 ablation target areas with a radius of 2 cm defined by success of radiofrequency (RF) ablation or entrainment during VT, or both. RESULTS: Of 1072 sites, 227 (21%) were in the target and 845 (79%) were outside the target. All parameters were significantly different (p < 0.05) in AP and in RVP between inside and outside the target in a univariate analysis. In a multivariate analysis LAT, END, DUR, and AMP in AP, END and AMP in RVP, and S-QRS were independent predictors for the target (p < 0.05). A combination of selected parameters of these predictors (DUR in AP, AMP in RVP, and S-QRS) had a specificity of 64% with a sensitivity of 80% for the target. CONCLUSION: The observations suggest that ablation guided by a combination of abnormal electrograms in different rhythms can be useful to ablate VT and reduce the necessity of VT induction. Anatomically fixed regions of block may be important for reentry and be identifiable during sinus rhythm