Song-Nan Li

Anatomical localization of isocitrate dehydrogenase 1 mutation: a voxel-based radiographic study of 146 low-grade gliomas

A brain tumors location is associated with the genetic profile of its tumor precursor cells. Mutations in isocitrate dehydrogenase 1 (IDH1) are an early event in tumor development and play a critical role in gliomagenesis. This study was conducted to specify the anatomical characteristics of IDH1 mutation in low‐grade gliomas and to further explore the origin of gliomas with IDH1 mutation. The impact of IDH1 mutation on disease prognosis was also evaluated.

Plasma galectin-3 predicts clinical outcomes after catheter ablation in persistent atrial fibrillation patients without structural heart disease.

AIMS This study sought to explore the relationship between plasma galectin-3 (Gal-3) and persistent atrial fibrillation (PsAF), and investigate whether Gal-3 predicts clinical outcomes in patients with PsAF undergoing catheter ablation. METHODS Fifty consecutive PsAF patients without coexisting structural heart disease undergoing first-time catheter ablation and 46 healthy controls were included. Blood samples were collected on admission for analysis of plasma Gal-3. Pre-ablation clinical and laboratory data were also recorded. Persistent atrial fibrillations patients were followed after ablation and AF recurrence was defined as episodes of AF or atrial tachycardia lasting >30 s after the blanking period. RESULTS Plasma Gal-3 concentrations were higher in PsAF patients than in healthy controls (P < 0.001). In PsAF group, those with AF recurrence had higher plasma Gal-3 than did those without recurrence (P = 0.007). Both Gal-3 (hazard ratio 1.28, P = 0.006) and left atrial diameter (LAD) (hazard ratio 1.1, P = 0.025) were independent predictors of AF recurrence after ablation. Moreover, adding Gal-3 to LAD had an incremental predictive value for ablation outcomes (global χ(2) of LAD alone: 8.2; LAD and Gal-3 concentrations: 15.7; P = 0.006). CONCLUSION Plasma Gal-3 concentrations are elevated in PsAF patients without structural heart disease and independently predict AF recurrence after ablation. Plasma Gal-3 concentration may be helpful in identifying appropriate candidates for AF ablation.

Over 1-year efficacy and safety of left atrial appendage occlusion versus novel oral anticoagulants for stroke prevention in atrial fibrillation: A systematic review and meta-analysis of randomized controlled trials and observational studies

BACKGROUND A direct comparison of the efficacy and safety profiles of left atrial appendage occlusion (LAAO) devices and novel oral anticoagulants (NOACs) for stroke prevention in atrial fibrillation is warranted but currently unavailable. OBJECTIVE The aim of this study was to compare the >1-year efficacy and safety of LAAO devices and NOACs for stroke prevention in patients with atrial fibrillation. METHODS We performed a systematic review on randomized controlled trials (RCTs) and observational studies. RCTs were analyzed by means of a network meta-analysis method using warfarin as a bridge to compare LAAO to individual NOAC or all NOACs as a whole. Observational studies were analyzed with the meta-proportion function where pooled event rates were compared. RESULTS A total of 6 RCTs and 27 observational studies were included. A network meta-analysis of RCTs indicated that LAAO was less effective than NOACs for stroke prevention (odds ratio 0.86), but had a lower rate of hemorrhagic events during follow-up. However, a meta-proportion analysis of observational studies revealed that LAAO devices were associated with a lower rate of both thromboembolic events (1.8 events per 100 patient-years vs 2.4 events per 100 patient-years) and major bleeding events during follow-up (2.2 events per 100 patient-years vs 2.5 events per 100 patient-years) as compared with NOACs. With prolonged follow-up duration after LAAO implantation, the rate of thromboembolic events decreased (2.1, 1.8, and 1.0 events per 100 person-years for 1, 1-2, and >2 years, respectively). CONCLUSION Although superiority of LAAO over NOACs was not demonstrated by RCTs in terms of stroke prevention, LAAO was found to be consistently associated with a lower rate of both thromboembolic and hemorrhagic events as compared with NOACs in observational studies.

Isolated Conduction Within the Left His-Purkenje System During Sinus Rhythm and Idiopathic Left Ventricle Tachycardia Findings From Mapping the Whole Conduction System

Background—Functionally, left His-Purkenje system (HPS) is insulated from the adjacent myocardium and exhibits isolated conduction during sinus rhythm (SR), but in vivo human study is rare. Meanwhile, whether the isolated conduction also exists during idiopathic left ventricle tachycardia (ILVT) is not clearly defined. The current study aimed to delineate the activation sequence and gross anatomy of left HPS during SR and ILVT. Methods and Results—The study involved 25 consecutive patients with ILVT. During SR, left HPS exhibited antegrade activation sequence, and its surrounding myocardium depolarized after HPS in an apical to base direction. During ILVT, the earliest retrograde presystolic potentials were mainly located at the middle portion of left posterior fascicle (0.5±0.1 [95% confidence interval, 0.46–0.58] of its full length) with an average of 29.5±6.0 mm (19.8–41.5) away from the His position. Left posterior fascicle was depolarized from the earliest retrograde presystolic potentials via 2 opposite wavefronts with significantly shorter activation time than that during SR (15.1±2.1 versus 30.0±3.2 ms; P<0.001). The left anterior fascicle was depolarized after left posterior fascicle with an antegrade activation sequence and comparable activation time with that during SR (21.9±2.9 versus 22.0±4.1 ms; P=0.932). The depolarization of ventricle septum also occurred after HPS in an apical to base direction. Conclusions—During SR, isolated conduction within the HPS is demonstrated by documenting the reverse activation sequence with its surrounding myocardium. During ILVT, the earliest retrograde presystolic potentials were usually recorded at the middle segment of left posterior fascicle, and the isolated conduction within the HPS remained.

Isolated Conduction Within the Left His-Purkenje System During Sinus Rhythm and Idiopathic Left Ventricle TachycardiaClinical Perspective

Background—Functionally, left His-Purkenje system (HPS) is insulated from the adjacent myocardium and exhibits isolated conduction during sinus rhythm (SR), but in vivo human study is rare. Meanwhile, whether the isolated conduction also exists during idiopathic left ventricle tachycardia (ILVT) is not clearly defined. The current study aimed to delineate the activation sequence and gross anatomy of left HPS during SR and ILVT. Methods and Results—The study involved 25 consecutive patients with ILVT. During SR, left HPS exhibited antegrade activation sequence, and its surrounding myocardium depolarized after HPS in an apical to base direction. During ILVT, the earliest retrograde presystolic potentials were mainly located at the middle portion of left posterior fascicle (0.5±0.1 [95% confidence interval, 0.46–0.58] of its full length) with an average of 29.5±6.0 mm (19.8–41.5) away from the His position. Left posterior fascicle was depolarized from the earliest retrograde presystolic potentials via 2 opposite wavefronts with significantly shorter activation time than that during SR (15.1±2.1 versus 30.0±3.2 ms; P<0.001). The left anterior fascicle was depolarized after left posterior fascicle with an antegrade activation sequence and comparable activation time with that during SR (21.9±2.9 versus 22.0±4.1 ms; P=0.932). The depolarization of ventricle septum also occurred after HPS in an apical to base direction. Conclusions—During SR, isolated conduction within the HPS is demonstrated by documenting the reverse activation sequence with its surrounding myocardium. During ILVT, the earliest retrograde presystolic potentials were usually recorded at the middle segment of left posterior fascicle, and the isolated conduction within the HPS remained.

Periprocedural anticoagulation of patients undergoing pericardiocentesis for cardiac tamponade complicating catheter ablation of atrial fibrillation.

Anticoagulation of patients with cardiac tamponade (CT) complicating catheter ablation of atrial fibrillation (AF) is an ongoing problem. The aim of this study was to survey the clinical practice of periprocedural anticoagulation in such patients. This study analyzed the periprocedural anticoagulation of 17 patients with CT complicating AF ablation. Emergent pericardiocentesis was performed once CT was confirmed. The mean drained volume was 410.0 ± 194.1 mL. Protamine sulfate was administered to neutralize heparin (1 mg neutralizes 100 units heparin) in 11 patients with persistent pericardial bleeding and vitamin K1 (10 mg) was given to reverse warfarin in 3 patients with supratherapeutic INR (INR > 2.1). Drainage catheters were removed 12 hours after echocardiography confirmed absence of intrapericardial bleeding and anticoagulation therapy was restored 12 hours after removing the catheter. Fifteen patients took oral warfarin and 10 of them were given subcutaneous injection of LMWH (1 mg/kg, twice daily) as a bridge to resumption of systemic anticoagulation with warfarin. Two patients with a small amount of persistent pericardial effusion were given LMWH on days 5 and 13, and warfarin on days 6 and 24. The dosage of warfarin was adjusted to keep the INR within 2-3 in all patients. After 12 months of follow-up, all patients had no neurological events and no occurrence of delayed CT. The results showed that it was effective and safe to resume anticoagulation therapy 12 hours after removal of the drainage catheter. This may help to prevent thromboembolic events following catheter ablation of AF.

QTc Interval Prolongation Predicts Arrhythmia Recurrence After Catheter Ablation of Atrial Fibrillation in Patients With Hypertrophic Cardiomyopathy

BACKGROUND In hypertrophic cardiomyopathy (HCM) patients complicated with atrial fibrillation (AF), catheter ablation has been recommended as a treatment option. Meanwhile, prolongation of QTc interval has been linked to an increased AF incidence in the general population and to poor outcomes in HCM patients. However, whether QTc prolongation predicts arrhythmia recurrence after AF ablation in the HCM population remains unknown. METHODS AND RESULTS Thirty-nine HCM patients undergoing primary AF ablation were enrolled. The ablation strategy included bilateral pulmonary vein isolation (PVI) for paroxysmal AF (n=27) and PVI plus left atrial roof, mitral isthmus and tricuspid isthmus linear ablations for persistent AF (n=12). Pre-procedural QTc was corrected by using the Bazetts formula. At a 14.8-month follow up, 23 patients experienced atrial tachyarrhythmia recurrence. Recurrent patients had longer QTc than non-recurrent patients (461.0±28.8 ms vs. 434.3±18.2 ms, P=0.002). QTc and left atrial diameter (LAD) were independent predictors of recurrence. The cut-off value of QTc 448 ms predicted arrhythmia recurrence with a sensitivity of 73.9% and a specificity of 81.2%. A combination of LAD and QTc (global chi-squared=13.209) was better than LAD alone (global chi-squared=6.888) or QTc alone (global chi-squared=8.977) in predicting arrhythmia recurrence after AF ablation in HCM patients. CONCLUSIONS QTc prolongation is an independent predictor of arrhythmia recurrence in HCM patients undergoing AF ablation, and might be useful for identifying those patients likely to have a better outcome following the procedure.

Long-term results of single-procedure catheter ablation for atrial fibrillationin pre- and post-menopausal women

Objectives To address whether menopause affects outcome of catheter ablation (CA) for atrial fibrillation (AF) by comparing the safety and long-term outcome of a single-procedure in pre- and post-menopausal women. Methods A total of 743 female patients who underwent a single CA procedure of drug-refractory AF were retrospectively analyzed. The differences in clinical presentation and outcomes of CA for AF between the pre-menopausal women (PreM group, 94 patients, 12.7%) and the post-menopausal women (PostM group, 649 patients, 87.3%) were assessed. Results The patients in the PreM group were younger (P < 0.001) and less likely to have hypertension (P < 0.001) and diabetes (P = 0.005) than those in the PostM group. The two groups were similar with regards to the proportion of concomitant mitral valve regurgitation coronary artery disease, left atrium dimensions, and left ventricular ejection fraction. The overall rate of complications related to AF ablation was similar in both groups (P = 0.385). After 43 (16–108) months of follow-up, the success rate of ablation was 54.3% in the PreM group and 54.2% in the PostM group (P = 0.842). The overall freedom from atrial tachyarrhythmia recurrence was similar in both groups. Menopause was not found to be an independent predictive factor of the recurrence of atrial tachyarrhythmia. Conclusions The long-term outcomes of single-procedure CA for AF are similar in pre- and post-menopausal women. Results indicated that CA of AF appears to be as safe and effective in pre-menopausal women as in post-menopausal women.

Ablation of left-sided accessory pathways with atrial insertion away from the mitral annulus using an electroanatomical mapping system.

A left‐sided accessory pathway (AP) with atrial insertion away from the mitral annulus (MA) may result in difficulty or failed ablation along the MA. We report our initial experience of ablating this rare form of AP by a 3‐dimensional electroanatomical mapping system (CARTO).

Catheter ablation of atrial fibrillation in patients with rheumatoid arthritis.

BACKGROUND Rheumatoid arthritis (RA) is associated with an increased incidence of atrial fibrillation (AF). This study evaluated the safety and efficacy of catheter ablation (CA) in the treatment of AF in patients with RA, which has not been previously reported. METHODS A total of 15 RA patients with AF who underwent CA were enrolled. For each RA patient, we selected 4 individuals (control group, 60 patients in total) who presented for AF ablation in the absence of structural heart or systemic disease and matched the RA patients with same gender, age (±2 years), type of AF, and procedure date. RESULTS Patients with RA had a significantly higher C-reactive protein level (1.81 ± 2.35 mg/dl vs. 4.14 ± 2.30 mg/dl, p=0.0320), white blood cell count (5632 ± 1200 mm(3) vs. 6361 ± 1567 mm(3), p=0.0482), and neutrophil count (3308 ± 973 mm(3) vs. 3949 ± 1461 mm(3), p=0.0441). At 2-year follow-up, atrial tachyarrhythmia (ATa) recurrence rate in the RA group (33.3%, 5/15) was similar to that in the control group (31.7%, 19/60; p=0.579) after single procedure. In all the five patients from the RA group who developed recurrence, ATa relapsed within 90 days following index procedure (median recurrence time 18 days vs. 92 days in control group; p=0.0373). Multivariate Cox regression analysis showed that hypertension and left atrial diameter but not RA, C-reactive protein, white blood cell count, and neutrophil count were independent predictors of ATa recurrence. CONCLUSIONS Catheter ablation of AF can be safely performed in patients with RA, with a success rate comparable to that of patients without RA. RA patients tend to develop early ATa recurrence after AF ablation.