One-year outcomes of wide antral cryoballoon ablation guided by high-density mapping vs. conventional cryoballoon ablation for atrial fibrillation: a propensity score-matched study.

Background: Pulmonary vein isolation with wide antral ablation leads to better clinical outcomes for the treatment of atrial fibrillation, but the isolation lesion is invisible in conventional cryoballoon ablation. In this study, we aim to investigate the efficacy of the wide pulmonary vein isolation technique that includes the intervenous carina region, guided by high-density mapping, compared with pulmonary vein isolation alone without the mapping system. Methods: We conducted a propensity score-matched comparison of 74 patients who underwent a wide cryoballoon ablation guided by high-density mapping (mapping group) and 74 controls who underwent conventional cryoballoon ablation in the same period (no-mapping group). The primary outcome was a clinical recurrence of documented atrial arrhythmias for >30 s during the 1-year follow-up. Results: Of 74 patients in the mapping group, residual local potential in the pulmonary vein antrum was found in 30 (40.5%) patients, and additional cryothermal applications were performed to achieve a wide pulmonary vein isolation. Compared with the no-mapping group, the use of the mapping system in the mapping group was associated with a longer fluoroscopic time (26.97 ± 8.07 min vs. 23.76 ± 8.36 min, P = 0.023) and greater fluoroscopic exposure [339 (IQR181-586) mGy vs. 224 (IQR133-409) mGy, P = 0.012]. However, no significant differences between the two groups were found in terms of procedural duration and left atrial dwell time (104.10 ± 18.76 min vs. 102.45 ± 21.01 min, P = 0.619; 83.52 ± 17.01 min vs. 79.59 ± 17.96 min, P = 0.177). The rate of 12-month freedom from clinical atrial arrhythmia recurrence was 85.1% in the mapping group and 70.3% in the no-mapping group (log-rank P = 0.029). Conclusion: Voltage and pulmonary vein potential mapping after cryoballoon pulmonary vein isolation can identify residual potential in the pulmonary vein antrum, and additional cryoablation guided by mapping leads to improved freedom from atrial arrhythmias compared with conventional pulmonary vein isolation without the mapping system. Clinical Trial Registration Number: ChiCTR2200064383.

Comparison of intracardiac vs. transesophageal echocardiography for "one-stop" procedures of combined radiofrequency catheter ablation and left atrial appendage closure with the Watchman device in the treatment of atrial fibrillation.

Background and objective: This study aimed to assess the efficacy and safety of "one-stop" procedures that combined radiofrequency catheter ablation and left atrial appendage closure (LAAC) with the Watchman device under the guidance of intracardiac echocardiography (ICE) vs. transesophageal echocardiography (TEE) in patients with atrial fibrillation. Methods and results: In this study, we prospectively enrolled patients who underwent "one-stop" procedures under the guidance of ICE (n = 193, 109 men, 65.02 ± 8.47 years) or TEE (n = 109, 69 men, 64.23 ± 7.75 years) between January 2021 and October 2022. Intraprocedural thrombus formation in the left atrial appendage (LAA) was observed in 3 (1.46%) patients in the ICE group and 15 (11.63%) patients in the TEE group (P < 0.05) before LAAC. Total fluoroscopy time and dose in the ICE group were less than those in the TEE group. The total "one-stop" turnaround time and LAAC procedure time in the ICE group were significantly shorter than those in the TEE group (P < 0.05). Postoperative esophagus discomfort, nausea and vomiting, and hypotension were more often seen in the TEE group (P < 0.001). There was no significant difference in matched cases between ICE and fluoroscopy measurements (P = 0.082). The TEE results related to LAAC and clinical events were similar between the two groups during the follow-up (P > 0.05). Conclusion: The ICE-guided "one-stop" procedure was safe and feasible with less radiation exposure, shorter turnaround time, and fewer complications and intraoperative thrombus formations than the TEE group. ICE offered accurate measurements in the LAA dimension during LAAC. Echocardiography during the "one-stop" procedures was necessary to rule out the intraoperative thrombus.

Bachmann's Bundle Modification in Addition to Circumferential Pulmonary Vein Isolation for Atrial Fibrillation: A Novel Ablation Strategy.

Background: Bachmann's bundle (BB) is the main pathway of interatrial connection that could be involved in the development of atrial fibrillation (AF). Based on this hypothesis, we raised a novel ablation strategy, BB modification in addition to circumferential pulmonary vein isolation (CPVI-BB) in patients with AF. Methods: A retrospective cohort of patients with AF who underwent CPVI-BB or CPVI alone from March 2018 to July 2021 was enrolled in our study. Propensity score matching was performed in patients with paroxysmal AF and persistent AF, respectively, to reduce the risk of selection bias between the treatment strategies (CPVI-BB or CPVI alone). The primary endpoint was overall freedom from atrial arrhythmia recurrence through 12 months of follow-up. Results: Our propensity score-matched cohort included 82 patients with paroxysmal AF (CPVI group: n = 41; CPVI-BB group: n = 41) and 168 patients with persistent AF (CPVI group: n = 84; CPVI-BB group: n = 84). Among patients with persistent AF, one-year freedom from atrial arrhythmia recurrence rate was 83.3% in the CPVI-BB group and 70.2% in the CPVI group (log-rank P = 0.047). Among patients with paroxysmal AF, no significant difference was found in the primary endpoint between two groups (85.4% in the CPVI-BB group vs. 80.5% in the CPVI group; log-rank P = 0.581). In addition, procedure-related complications and recurrence of atrial tachycardia or atrial flutter were similar between the two treatment groups, regardless of the type of AF. Conclusions: BB modification in addition to CPVI is an effective approach in increasing the maintenance of sinus rhythm in patients with persistent AF, while it does not improve the clinical outcomes of radiofrequency catheter ablation in patients with paroxysmal AF.

Characteristics and Ablation Outcomes of Atrial Tachycardia in Patients with Prior Cardiac Surgery vs. Spontaneous Scars: Where Are the Differences?

(1) Background: Atrial scars play an important role in atrial tachycardia (AT). They can not only be found in patients with prior cardiac surgery (PCS) but also in patients without PCS or significant structural heart disease, in which case the scar is called a spontaneous scar (SS). This study aims to compare the characteristics, mechanisms and ablation outcomes of AT in patients with PCS and SS. (2) Methods: We retrospectively reviewed electrophysiological and ablative characteristics of ATs in 46 patients with PCS and 18 patients with SS. (3) Results: There were averages of 1.52 and 2.33 ATs per patient in the PCS group and SS group, respectively (p < 0.01). Cavo-tricuspid isthmus dependent atrial flutter (CTI-AFL) was presented in most patients in both groups (93.50% vs. 77.80%, p = 0.17), whereas the SS group had a higher occurrence of scar-mediated reentrant AT (SMAT) and focal AT (FAT) compared with the PCS group (88.90% vs. 39.10%, p < 0.01; 22.2% vs. 2.2%, p < 0.05). There were no significant differences in acute success rate between the two groups, whereas patients with SS had lower long-term success rate (87.0% vs. 61.1%, p < 0.05) and higher occurrence of sinus node dysfunction (SND) (4.3% vs. 22.2%, p < 0.05). (4) Conclusions: CTI-AFL is common in both patients with PCS and SS, and routine CTI ablation is recommended. Compared with patients with PCS, patients with SS have more ATs, especially with higher occurrence of SMAT and FAT, and had a lower long-term success rate and higher incidence of SND.

The change of cardiac axis deviation in catheter ablation of verapamil-sensitive idiopathic left ventricular tachycardia.

BACKGROUND: The underlying mechanism of verapamil-sensitive idiopathic left ventricular tachycardia (ILVT) has been postulated to be reentrant activation in the Purkinje fiber network of the left posterior fascicle or the left anterior fascicle (LAF). However, changing of cardiac axis deviation in sinus rhythm (SR) or during ILVT after radiofrequency catheter ablation (RFCA) has been rarely analyzed. METHODS: Of the 232 patients with sustained ILVT induced and surface electrocardiogram (ECG) in SR recorded before and after RFCA, the changes of ECG morphology in SR and during ILVT were analyzed. RESULTS: The surface ECG in SR changed in 114 (49.1%) patients after RFCA. ILVT could still be induced in 27 (23.7%) patients. In comparison with the original ILVT, three forms of ECG morphology were observed. In eight patients, the ILVT morphology was unchanged. In the 13 patients with ILVT axis deviation conversion after ablation, the successful target was more proximal. In the six patients with ILVT morphology change but without axis deviation conversion after ablation, the successful ablation site was more distal. Among 15 patients with recurrent ILVT during follow-up, seven patients had previous axis deviation changes in SR after RFCA, the changes maintained in four patients and recovered in three patients. CONCLUSIONS: The morphology changes on surface ECG in SR after RFCA would not be a necessary prerequisite or a good endpoint for ILVT ablation. To analyze ILVT morphology changes after ablation would help to further clarify an appropriate approach for catheter ablation of ILVT.

Surface electrocardiography characteristics and radiofrequency catheter ablation of idiopathic ventricular arrhythmias originating from the left infero-septal papillary muscles: differences from those originating from the left posterior fascicle.

Aims: Distinguishing between ventricular arrhythmias originating from the left ventricular infero-septal papillary muscles (PM) and those from the left posterior fascicle (LPF) by surface electrocardiography (ECG) is very difficult. This study aimed to report the ECG characteristics and radiofrequency catheter ablation of PM and LPF ventricular arrhythmias. Methods and results: A total of 127 patients underwent catheter ablation of idiopathic ventricular arrhythmias originating from the LPF (n = 106; 85 males; 10-70 years) or PM (n = 21; 14 males; 4-68 years) were studied. A three-dimensional electroanatomic system (3D-EAS) was used to aid ablation. PM ventricular arrhythmias had a longer QRS duration (154.4 ± 18.0 vs. 119.7 ± 12.6 ms, P < 0.001) than LPF ventricular arrhythmias. All 7 ventricular arrhythmias with QRS duration >160 ms originated from the PM, whereas all 87 ventricular arrhythmias with QRS duration <130 ms arose from the LPF. In 33 ventricular arrhythmias with QRS 130-160 ms, all 13 with Vi/Vt ≤ 0.85 originated from the PM, and 19 of 20 with Vi/Vt > 0.85 arose from the LPF. Of the 8 PM ventricular arrhythmias patients whose initial ablation was undertaken using a non-irrigated 4 mm-tip catheter, 1 failed and 6 recurred. However, of the remaining 13 ones using an irrigated catheter and the 3D-EAS, all succeeded and 2 recurred. No complications were noted in any patient. Conclusion: PM ventricular arrhythmias could be identified from LPF ventricular arrhythmias by calculation of QRS duration combined with Vi/Vt using ECG.

Different Approaches for Catheter Ablation of Para-Hisian Accessory Pathways: Implications for Mapping and Ablation.

BACKGROUND: Catheter ablation of para-Hisian accessory pathways (APs) can be challenging because of adjacent conduction tissue. Some different approaches for ablation, including the inferior vena cava approach (IVC-A), the noncoronary cusp approach (NCC-A), or the superior vena cava approach (SVC-A), have been reported. However, when should para-Hisian APs be mapped and ablated by the IVC-A, NCC-A, or SVC-A is not well established. METHODS AND RESULTS: This study included 55 consecutive patients (mean age, 53±11 years, 36 males) with para-Hisian APs. On the basis of the approach resulting in successful ablation, patients were divided into IVC-A, NCC-A, and SVC-A groups. The clinical characteristics, surface ECG, intracardiac electrogram findings, and response to ablation were analyzed. Para-Hisian APs were eliminated by IVC-A in 48 of the 55 (87%) patients. The rates of para-Hisian APs requiring NCC-A (4/55 patients, 7%) and SVC-A (3/55 patients, 6%) were relatively low. During mapping at the para-Hisian region, the local ventricular and atrial potentials were well fused during retrograde AP conduction in 45 of the 48 patients in IVC-A group, 0 of the 4 patients in NCC-A group, and 1 of the 3 patients in SVC-A group, respectively. There was no significant difference in the preexcitation characteristics among the 3 groups. CONCLUSION: Most para-Hisian APs can be safely and effectively ablated by IVC-A, and ablation in the NCC is not an initial or a preferred approach. The degree of local ventriculoatrial fusion in the para-Hisian region during retrograde AP conduction can differentiate or predict the successful ablation site.

Focal atrial tachycardia surrounding the anterior septum: strategy for mapping and catheter ablation.

BACKGROUND: Focal atrial tachycardias (ATs) surrounding the anterior atrial septum (AAS) have been successfully ablated from the right atrial septum (RAS), the aortic cusps, and the aortic mitral junction. However, the strategy for mapping and ablation of AAS-ATs has not been well defined. METHODS AND RESULTS: Of 227 consecutive patients with AT, 47 (20.7%; mean age, 56.3±11.6 years) with AAS-ATs were studied; among them, initial ablation was successful at RAS in only 5 of 14 patients and at noncoronary cusp (NCC) in 28 of 33 patients. In 45 of the 47 patients, the 46 of 48 AAS-ATs were eliminated at RAS in 8 patients, NCC in 35 patients (earliest activation time at NCC was later than that at RAS by 5-10 ms in 6 patients), and aortic mitral junction in 3 patients (all with negative P wave in lead aVL and positive P wave in the inferior leads), including 1 patient whose 2 ATs were eliminated separately from the NCC and the aortic mitral junction. CONCLUSIONS: Most of the ATs surrounding the AAS can be eliminated from within the NCC, which is usually the preferential ablation site. Ablation at the RAS and aortic mitral junction should be considered when supported by P-wave morphologies on surface ECG and results of activation mapping and ablation.

[Spatiotemporal distribution of air temperature and precipitation in rice growth period in Fujian Province of East China and the effects of this distribution on rice planting pattern].

In order to investigate the effects of climate change on the rice production and rice planting pattern in Fujian Province, an analysis was made on the spatiotemporal distribution of air temperature and precipitation in rice growth period in the Province, and the possible changes of the local rice planting pattern in the future, based on the A2, B2, and A1 B scenarios of IPCC Special Report on Emission Scenario (SRES). In the future, the rice growth period's air temperature in the Province tended to be increased, and the increment would be increased with time, with the maximum for single cropping rice and being 0.3-2.4 degrees C and 1.5-3.4 degrees C in 2011-2030 and 2031 -2050, respectively. For early rice and late rice, the increment of their growth period's air temperature would be 0.2-0.9 degrees C and 0.7-1.7 degrees C in 2011-2030 and 0.3-2.1 degrees C and 0.5-3.6 degrees C in 2031-2050, respectively, but the annual fluctuation of the mean daily temperature would be most obvious for late rice. The rice growth period's precipitation in most parts of the Province also tended to be increased, and the increment for early rice, single cropping rice, and late rice would be 10%-40%, 10%-30%, and 10%-20%, respectively. The annual fluctuation of the precipitation would be most obvious for the early rice in southeastern Fujian. The elevated air temperature in the future could induce the increase of > or = 10 degrees C accumulated temperature, and lengthen the rice growth season, making it possible to replace early and medium-maturity varieties with late-maturity varieties, and to adopt double-rice planting pattern instead of single-rice planting pattern.

Electrophysiological characteristics of focal atrial tachycardia surrounding the aortic coronary cusps.

BACKGROUND: Catheter ablation of atrial tachycardia (AT) arising near the coronary cusps has been reported in limited numbers of patients. We investigated the electrophysiological characteristics of these ATs in 22 consecutive patients. METHODS AND RESULTS: This study included 22 patients (mean age ± SD, 53 ± 11 years; 86% female) with ATs arising near the aortic coronary cusps who underwent successful ablation. Activation mapping was performed during tachycardia to identify the earliest activation site. All patients achieved successful ablation through either a retrograde aortic (n=19) or a transseptal (n=3) approach. The successful ablation sites were located in the noncoronary cusp (NCC) (n=16), including 3 near the junction between the NCC and right coronary cusp. The remaining 6 cases were ablated from the left coronary cusp (LCC) (n=3) or the left atrium posterior to the LCC (n=3). For most tachycardias, there were distinctive P-wave morphological features recorded for each cusp location. Furthermore, analysis of the electrogram morphological features recorded during tachycardia at successful ablation sites revealed an atrial/ventricular (A/V) ratio >1 in 14 of 16 NCC ATs; the remaining 2, from the NCC near the junction with the right coronary cusp, showed an A/V ratio ≤ 1. At ablation sites in the LCC, the A/V ratio was <1 (4 of 6 patients) or 1 (remaining 2 patients). During a follow-up duration of 30 ± 13 months, all patients were free of arrhythmias without antiarrhythmic drugs. CONCLUSIONS: ATs surrounding the aortic coronary cusps can be safely and effectively ablated, with good long-term outcomes. In addition to the P-wave morphological features, the A/V ratio of the local electrogram recording during tachycardia facilitated the localization of successful sites.

[Effects of high temperature on grain filling and some physiological characteristic in flag leaves of hybrid rice].

The effects of high temperature on grain filling rate and some physiological indexes in flag leaves in hybrid rice Teyou 559 were studied. The results showed that chlorophyll content and superoxide dismutase (SOD) activity in flag leaves were lower significantly by high temperature stress (Figs.2A and 3A). The electrolyte leakage and malondialdehyde (MDA) content were higher significantly under high temperature stress (Figs.2B and 3B). The proline (Pro), ascorbic acid (AsA), glutathione (GSH), soluble protein and soluble sugar contents were lower significantly by high temperature stress than those of the control (Figs.4,5 and 6). Both the rate of grain filling and grain dry matter accumulation become lower significantly under high temperature stress (Figs.7 and 8). Therefore, it was suggested that high temperature accelerated the senescence of rice leaf and decreased the photosynthesis rate during grain filling period, and then which was the main reason in physiology which resulted the decrease of grain filling rate, seed setting rate, grain weight and yield.

[Expression of macrophage migration inhibition factor in pancreatic carcinoma tissue].

OBJECTIVE: To observe the expression of macrophage migration inhibitory factor (MIF) in pancreatic carcinoma tissue and analyze the relationship between MIF expression and clinical manifestations. METHODS: MIF expression in pancreatic carcinoma and normal pancreatic tissue were detected with immunohistochemical method. RESULT: The positivity rates of MIF in pancreatic carcinoma and normal pancreatic tissue were 69.4% (25/36) and 0 (0/10) respectively. MIF expression was found to relate to the degree of cell differentiation of pancreatic carcinoma, but not to the clinical stages or the status of lymph node metastasis. CONCLUSION: MIF might be related to the pathogenesis of pancreatic carcinoma.