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Background: Supraventricular tachycardia (SVT) with coronary sinus (CS) ostial atresia (CSA) or coronary sinus stenosis (CSS) causes difficulty in electrophysiological procedures, but its characteristics are poorly understood. Objective: Study the anatomical and clinical features of SVT patients with CSA/CSS. Methods: Of 6128 patients with SVT undergoing electrophysiological procedures, consecutive patients with CSA/CSS were enrolled, and the baseline characteristics, imaging materials, intraoperative data, and follow‐up outcomes were analyzed. Results: Thirteen patients, seven with CSA and six with CSS, underwent the electrophysiological procedure. Decapolar catheters were placed into the proximal CS in three cases, while the rest were placed at the free wall of the right atrium. Fourteen arrhythmias were confirmed: four atrioventricular nodal reentrant tachycardias, five left‐sided accessory pathways, three paroxysmal atrial fibrillations, and two atrial flutters (AFLs). In addition to three patients who underwent only an electrophysiological study, the acute ablation success rate was 100% in 10 cases, with no procedure‐related complications. After a median follow‐up period of 59.6 months, only one case of atypical AFL recurred. For those cases (seven CSA and two CSS) with a total of 10 anomalous types of CS drainage, three types were classified: from the CS to the persistent left superior vena cava (n = 3), from an unroofed CS (n = 3), and from the CS to the small cardiac vein (n = 3) or Thebesian vein (n = 1). Conclusion: Patients with CSA/CSS may develop different kinds of SVT. Electrophysiological procedures for such patients are feasible and effective. An individualized mapping strategy based on the three types of CS drainage will be helpful. [ABSTRACT FROM AUTHOR]

Background: Ablation of right ventricular outflow tract (RVOT) ventricular arrhythmia (VA) within the left pulmonary sinus of Valsalva (LPSV) may increase the risk of left main coronary artery (LMCA) injury. Purpose: To delineate the anatomical characteristics between LMCA and LPSV and their association with atrial potential (AP) mapping in LPSV. Methods: A total of 104 consecutive patients with RVOT‐VA undergoing cardiac‐gated computed tomography coronary angiography (CTCA) after ablation were retrospectively analyzed. Results: The LMCA‐LPSV anatomic relationship was classified into three types based on the CTCA measurements. Types 1 and 2 had a shorter LMCA‐LPSV distance than that of type 3 (P < .001). The left atrial appendage (LAA)‐LMCA distance and LAA‐LPSV distance were associated with the incidence of AP in LPSV (odds ratio [OR] = 3.43, 95% confidence interval [CI]: 1.86‐6.34, P < .001; OR = 1.196, 95% CI: 1.09‐1.31, P < .001, respectively). Furthermore, the LMCA‐LPSV distance showed a linear correlation with the LAA‐LPSV distance (r2 = 0.93, P < .001). According to receiver operating characteristic (ROC) analysis, a LMCA‐LPSV distance <5.4 mm could predict the possibility of AP during LPSV mapping (sensitivity 83%, specificity 81%, and area under the ROC curve 0.86). Conclusions: The presence of AP in the LPSV may be useful to predict a short distance from the LPSV to the LMCA and to identify patients at higher risk of LMCA injury. This information may contribute to efficient and safe ablation in this area but should be confirmed in future studies. [ABSTRACT FROM AUTHOR]

Abstract: Background: Ablation within the pulmonary sinus of Valsalva (PSV) becomes increasingly common in certain ventricular outflow arrhythmia. Understanding the regional anatomy is intensively concerned to avoid procedure complications. Purpose: To describe the anatomic relationships of PSV to its adjacent structures using computed tomographic coronary angiograms (CTCA). Methods: We studied 145 patients (77 males, age 47 ± 18 years) investigated for chest pain with CTCA. The relationships between the PSV and adjacent structures were described by analysis of 2‐dimensional images and 3‐dimensional reconstructions. Results: The left adjacent sinus (LAS) was located within 5 mm of the left main coronary artery (LMCA) in 67% cases (19% within 2 mm) and within 5 mm of the left anterior descending coronary artery (LAD) in 87% (36% within 2 mm). The anterior sinus was within 5 mm of the LAD in 1% and out of 5 mm from LMCA in all cases. Note that 93% LAS was within 5 mm of the left aortic sinus of Valsalva (LASV) (within 2 mm in 27%), remaining 80% right adjacent sinus (RAS) within 5 mm from ascending aorta. The right coronary artery (RCA) was within 5 mm of the RAS/right ventricular outflow tract in 82% cases. Conclusions: Both the left and RASs are intimately related to the aortic root. The LAS is more often close to LMCA, LAD, and the LASV. The anterior sinus is more frequently related to LAD than LMCA. This information may help heighten operator awareness of safety for increasingly performed complex procedures in this area. [ABSTRACT FROM AUTHOR]

Introduction Methods Results Conclusions The accuracy of surface ECG algorithms for predicting the origin of outflow tract ventricular arrhythmias (OT‐VAs) might be questioned. Intracardiac electrograms recorded at anatomic landmarks could provide new predictive insights. We aim to evaluate the efficacy of a novel criterion utilizing the activation pattern of the coronary sinus (CS) in localizing OT‐VAs, including VAs originating from the right ventricular outflow tract (RVOT), endocardial left ventricular outflow tract (Endo‐LVOT), and epicardial left ventricular outflow tract (Epi‐LVOT).We measured the ventricular activation time of the mitral annulus (MA) from the onset of the earliest QRS complex of VAs to the initial deflection over the isoelectric line at local signals, namely the QRS‐MA interval. The activation at 3 and 12 o'clock of the MA was recorded as the QRS‐MA3 and QRS‐MA12 intervals, respectively. Their predictive values were compared to previous ECG algorithms.A total of 68 patients with OT‐VAs were enrolled (51 for development and 17 for validation). From early to late, the ventricular activation sequences at MA12 were as follows: Epi‐LVOT, Endo‐LVOT, and RVOT. In LBBB morphology OT‐VAs, the QRS‐MA12 interval was significantly earlier for LVOT origins than RVOT origins. In the combined cohort of development and validation cohort, a cut‐off value of ≤10 ms predicted the LVOT origin with a sensitivity of 100% and specificity of 78%. The QRS‐MA12 interval ≤ −24 ms additionally predicted epicardial LVOT sites of origin.The QRS‐MA interval could accurately differentiate the OT‐VAs localization. [ABSTRACT FROM AUTHOR]

The 6-hole open-irrigated catheter (SHOI) is increasingly used in radiofrequency (RF) ablation of arrhythmias. However, deep transmural lesions are not always achieved, and volume overload caused by irrigated ablation is another problem that should be concerned. The purpose of this study was to analyze and compare the ablation effect and electrical morphology between a novel 18-hole open-irrigated catheter (EHOI) and SHOI. The heart was exposed through a median sternotomy in 12 anesthetized dogs, and the chest cavity was filled with heparinized saline. Bipolar contact pericardial electrograms of both catheters were recorded. Lesions were created under all permutations of the following conditions: RF energy 30 and 40 W for 60 seconds, contact force at 10, 30, and 50 g, electrode orientation horizontal to the tissue, irrigation rate 10 mL/min for EHOI and 17 mL/min for SHOI. The EHOI created deeper lesions than SHOI (5.77 ± 1.37 mm vs 4.98 ± 1.22 mm at power of 30 W, P < 0.05; 7.16 ± 1.15 mm vs 6.02 ± 1.04 mm at power of 40 W, P < 0.01), and there was a trend of larger lesion volume for EHOI (312 ± 141 mm vs 259 ± 108 mm at power of 30 W, 536 ± 200 mm vs 451 ± 180 mm at power of 40 W, P > 0.05). No significant difference in electrogram morphology between 2 catheters was detected. The mapping electrograms of EHOI and SHOI were not significantly different. Compared with SHOI, EHOI more effectively produced deeper lesions at a lower rate of irrigation perfusion. (J Cardiovasc Electrophysiol, Vol. 22, pp. 691-697, June 2011) [ABSTRACT FROM AUTHOR]

A Novel Cryoballoon Technique. Introduction: The study was designed to evaluate the feasibility and efficacy of a simplified cryoballoon technique in which a microcircular catheter was introduced into the central lumen of a cryoballoon catheter for the purpose of recording pulmonary vein (PV) potentials during ablation procedures and without interchanging catheters. Methods and Results: A total of 23 consecutive patients with paroxysmal atrial fibrillation (AF) were enrolled. A single transseptal puncture was made and a cryoballoon catheter was inserted into the left atrium. A 6-pole mapping catheter with a 0.035-inch shaft diameter was introduced into the PV through the central lumen of the cryoballoon catheter. In addition to the function as a recording device, the mapping catheter was also used as a “guide-wire” during the procedure. A total of 84 PVs (84/92, 91.3%) were completely isolated using this novel cryoballoon technique. In 43 of the 84 veins (51.2%), isolation was observed in real time during the cryoablation; in the remaining 41 veins (48.8%), isolation was confirmed immediately post ablation attempt with the mapping catheter. Procedure time was 152.7 ± 54.9 minutes, and fluoroscopy time was 33.2 ± 17.3 minutes. At follow-up (7.4 months, range 2–18 months), 17 (73.9%) patients were free from AF. There was 1 occurrence of phrenic nerve palsy during ablation of a right superior PV, which fully resolved after 1 month. Conclusion: The use of a cryoballoon catheter equipped with a 6-pole micromapping catheter inserted through its central lumen for the purpose of mapping and ablation during PV isolation procedures is both feasible and effective. (J Cardiovasc Electrophysiol, Vol. 21, pp. 626-631, June 2010) [ABSTRACT FROM AUTHOR]

Background: Pulsed‐field ablation (PFA) has emerged as a nonthermal energy source for cardiac ablation, with potential safety advantages over radiofrequency ablation (RFA) and cryoballoon ablation. Objective: To report the preclinical results of a novel hexaspline PFA catheter for pulmonary vein isolation (PVI), and to verify the influence of PFA on esophagus by comparing with RFA. Methods: This study included a total of 15 canines for the efficacy and safety study and four swine for the esophageal safety study. The 15 canines were divided into an acute cohort (n = 3), a 30‐day follow‐up cohort (n = 5) and a 90‐day follow‐up cohort (n = 7), PVI was performed with the novel hexaspline PFA ablation catheter. In the esophageal safety study, four swine were divided into PFA cohort (n = 2) and RFA cohort (n = 2), esophageal injury swine model was adopted, the esophagus was intubated with an esophageal balloon retractor, under fluoroscopy, the DV8 device was inflated with a mixture of saline and contrast and rotated to displace the esophagus rightward and anteriorly toward the ablation catheter in the inferior vena cava (IVC) and right inferior pulmonary vein (PV). Nine PFA applications were delivered at four locations on IVC and two locations on the right inferior PV in the PFA cohort, six RFA applications were delivered at each location in the RFA group. Histopathological analysis of all PVs, esophagus, IVC, and the adjacent lungs was performed. Results: Acute PV isolation was achieved in all 15 canines (100%), with energy delivery times of less than 3 min/animal. In the 30 and 90 days group, the overall success rates were 88.9% and 88.5% per PVs, respectively. Two right superior pulmonary veins (RSPVs) in the 30‐day group, two RSPVs and one left superior PV in the 90‐day group with recovered potentials. At follow‐up, gross pathological examination revealed the lesions around the PVs were continuous and transmural. Masson's trichrome staining revealed the myocardial cells in the PVs became fibrotic, but small arteries and nervous tissue were preserved. Results of swine esophageal injury model revealed the esophageal luminal surface was smooth and without evidence for esophageal injury in the PFA group, whereas obvious ulceration was detected on the esophagus tunica mucosa in the RFA group. Conclusion: In the chronic canine study, PFA‐based PVI were safe and effective with demonstrable sparing of nerves and venous tissue. Compared with RFA, there was also good evidence for safety of PFA, avoiding PV stenosis and esophageal injury. This preclinical study provided the scientific basis for the first‐in‐human endocardial PFA studies. [ABSTRACT FROM AUTHOR]

Introduction: Mapping and ablation through the coronary venous system (CVS) have shown potential for ventricular arrhythmias originating from the left ventricular summit (LVS). Multielectrode catheters and balloons are frequently used for mapping and venous ethanol ablation (VEA). However, there is limited data on the venous size and drainage condition in the LVS region. This study aimed to investigate the morphology, angiographic size, and drainage condition of LV summit veins via high‐speed rotational angiography (RA). Methods: We measured and analyzed the size of the great cardiac vein (GCV), the anterior interventricular vein (AIV), veins near to the LVS, and other main tributaries of CVS in 102 patients undergoing electrophysiology study. Results: Rotational retrograde angiography of LVS was successfully performed in 81 patients. The diameter of GCV at the level of the Vieussens valve and the distal end of GCV (junction of GCV‐AIV) was larger in males than females (6.8 ± 1.1 vs. 5.6 ± 1.2 mm, p <.001; 5.2 ± 0.9 vs. 4.6 ± 0.8, p =.002, respectively) while no significant gender differences were observed in other tributaries. The LV summit veins presented downward drainage direction in half of the patients, indicating potential anatomic adjacency with His bundle. Left anterior oblique (LAO) 45° projection might provide the practical and optimal view of the LV summit veins. Conclusions: The coronary veins of the LVS region present various anatomical morphologies and ostium sizes. We provide a systematic description and angiographic size spectrum of CVS. RA could facilitate assessing the feature of CVS comprehensively. [ABSTRACT FROM AUTHOR]

Background: The electrophysiological responses of the left atrial appendage (LAA) during pulsed‐field electrical isolation have not been established. Objective: This study aims to investigate the electrical responses of the LAA during pulsed‐field electrical isolation using a novel device and their relations to acute isolation success. Methods: Six canines were enrolled. The E‐SeaLA™ device, which is able to perform LAA occlusion and ablation simultaneously, was deployed into the LAA ostium. LAA potentials (LAAp) were mapped via a mapping catheter, and the LAAp recovery time (LAAp RT, the time between the last pulsed spike and the first recovered LAAp) was measured after pulsed‐train delivery. The initial pulse index (PI, corelated to pulsed‐field intensity) was adjusted during the ablation procedure until LAAEI was achieved. Acute LAA electrical isolation (LAAEI) success was defined as LAAp disappearance or exit and entrance conduction block, confirmed through a drug test and a 60‐minute waiting period. Result: All canines achieved successful LAA occlusion without peri‐device leaks. Acute LAA electrical isolation (LAAEI) was achieved in five out of six canines (5/6, 83.3%). Very late LAAp recurrence (LAAp RT > 600 s) was observed during PFA. Early recurrence (LAAp RT < 30 s) was observed in two canines (2/6, 33.3%) post‐PFA. Intermediate recurrence (LAAp RT ~ 120 s) was observed in three canines (3/6, 50%) post‐PFA. The two canines with intermediate recurrence achieved LAAEI with higher PI ablations. The one canine with early LAAp recurrence had a peri‐device leak and achieved LAAEI by the same PI after replacing with a larger size device and eliminating the peri‐device leak. Another canine with early recurrence (1/6, 16.7%) failed to achieve LAAEI due to epicardial connection with persistent left superior vena cava. No coronary spasm, stenosis or other complications were observed. Conclusion: These results suggest that with proper device‐tissue contact and pulse intensity, LAAEI can be achieved using this novel device without serious complications. The LAAp RT patterns observed in this study could inform and guide the adjustment of the ablation strategy. [ABSTRACT FROM AUTHOR]