Publications by authors named "Shiquan Chen"

13 Publications

  • Page 1 of 1

Intracardiac Echocardiography-Derived Right Ventricular Myocardial Strain Deformation Patterns with Segmental Dyssynchrony in Arrhythmogenic Cardiomyopathy.

J Am Soc Echocardiogr 2021 01 9;34(1):100-102. Epub 2020 Nov 9.

Cardiac Electrophysiology Laboratory, Cardiovascular Medicine Division, University of Pennsylvania Health System, Philadelphia, Pennsylvania.

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January 2021

Strategies for Catheter Ablation of Left Ventricular Papillary Muscle Arrhythmias: An Institutional Experience.

JACC Clin Electrophysiol 2020 10 16;6(11):1381-1392. Epub 2020 Sep 16.

Electrophysiology Section, Cardiology Division, Hospital of the University of Pennsylvania, Philadelphia, Pennsylvania, USA. Electronic address:

Objectives: This study sought to address whether technological innovations such as contact force sensing (CFS) can improve acute and long-term ablation outcomes of left ventricular papillary muscle (LV PAP) ventricular arrhythmias (VAs).

Background: Catheter ablation of LV PAP VAs has been less efficacious than another focal VAs. It remains unclear whether technological innovations such as CFS can improve acute and long-term ablation outcomes of LV PAP VA.

Methods: From January 2015 to December 2019, a total of 137 patients underwent LV PAP VA ablation. VA site of origin (SOO) was identified using activation and pace-mapping guided by intracardiac echocardiography. Radiofrequency energy (20 to 50 W for 60 to 90 s) was delivered by irrigated catheter with or without CFS. We defined acute success as complete suppression of targeted VA ≥30 min post ablation and clinical success as ≥80% VA burden reduction at outpatient follow-up.

Results: VA manifested as premature ventricular complexes in 98 (71%), nonsustained ventricular tachycardia in 18 (13%), sustained ventricular tachycardia in 12 (9%) and premature ventricular complexes induced ventricular fibrillation in 9 (7%). VA SOO was anterolateral PAP in 51 (37%), posteromedial PAP in 73 (53%), and both PAPs in 13 (10%). VAs were targeted using CFS in 97 (71%) and non-CFS in 40 (29%). After a single procedure, acute success was achieved in 130 (95%) and clinical success was achieved in 112 (82%); neither was impacted by VA SOO and/or CFS. Complications occurred in 5 patients (3.6%).

Conclusion: Independent of CFS technology, intracardiac echocardiography-guided catheter ablation is highly efficacious and may be considered as first-line therapy in the management of LV PAP VA.
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October 2020

Differential enrichment and physiological impacts of ingested microplastics in scleractinian corals in situ.

J Hazard Mater 2021 02 8;404(Pt B):124205. Epub 2020 Oct 8.

Department of Marine Sciences, University of Connecticut, Groton, CT, United States.

Microplastics are emerging contaminants and widespread in the ocean, but their impacts on coral reef ecosystems are poorly understood, and in situ study is still lacking. In the present study, the distribution patterns of microplastics in the environment and inhabiting organisms were investigated along the east coast of Hainan Island, South China Sea, and the physiological impacts of the microplastics on scleractinian corals were analyzed. We documented average microplastic concentrations of 14.90 particlesL in seawater, 343.04 particleskg in sediment, 4.97 particlescm in corals, and 0.67-3.12 particlescm in Tridacnidae, Trochidae and fish intestines. Further analysis revealed that the characteristics of microplastics in the organisms were different from those in the environment, indicating preferential enrichment in the organisms. Furthermore, there was an obvious correlation between microplastic concentration and symbiotic density in corals. Furthermore, caspase3 activity was significantly positively correlated with the microplastic content in the small-polyp coral Pocillopora damicornis, but the large-polyp coral Galaxea fascicularis showed higher tolerance to microplastics. Taken together, our results suggest that microplastics are selectively enriched in corals and other reef-dwellers, in which they exact differential stress (apoptotic) effects, with the potential to impact the coral-Symbiodiniaceae symbiosis and alter the coral community structure.
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February 2021

Esophageal contraction during cryoablation: A possible protective mechanism.

Pacing Clin Electrophysiol 2020 09 21;43(9):908-912. Epub 2020 Aug 21.

Heart Institute, Cedars Sinai Medical Center, Los Angeles, California.

Background: Contraction of the esophagus was observed during cryoablation for paroxysmal atrial fibrillation (PAF). The purpose of this study is to investigate the mechanism of esophageal contraction and the correlation between the contraction and esophageal thermal lesions.

Methods: This prospective study enrolled 64 patients with PAF undergoing second-generation cryoballoon (CB2) ablation for pulmonary vein isolation (PVI). During PVI for the left inferior pulmonary vein, contrast esophagography was performed before and during cryoablation. The sample population was divided into two groups: A (31 patients) and B (33 patients). Group A consisted of patients in whom the distal half of the CB was in proximity to the esophagus, while for group B the esophagus was away from the distal half of the CB. Esophageal contraction was recorded as a variation in the width of the esophageal lumen during PVI. Postablation esophageal endoscopy was done on all patients.

Results: The reduction in the width of the esophageal lumen in group A was greater than in group B during freezing (40.12 ± 23.24% vs 8.14 ± 10.35%, P < .001). Following endoscopy, no apparent esophageal lesion was detected in all patients.

Conclusion: The extent of esophageal contraction is correlated with the positioning of the esophagus at the distal half of the CB. The findings of this study indicate that esophageal contraction during freezing may be a self-protective mechanism.
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September 2020

Intraprocedural endpoints to predict durable pulmonary vein isolation: a randomized trial of four post-ablation techniques.

Europace 2020 04;22(4):567-575

Department of Cardiology, Sir Run Run Shaw Hospital, School of Medicine, Zhejiang University, Hangzhou, Zhejiang 310016, China.

Aims: The optimal procedural endpoint to achieve permanent pulmonary vein isolation (PVI) during ablation of atrial fibrillation (AF) remains unknown. We aimed to compare the impact of prolonged waiting periods and adenosine triphosphate (ATP) testing after PVI on long-term freedom from AF.

Methods And Results: In total, 538 patients (median age 61 years, 62% male) undergoing first-time radiofrequency ablation for paroxysmal AF were randomized into four groups: Group 1 [PVI (no testing), n = 121], Group 2 (PVI + 30min waiting phase, n = 151), Group 3 (PVI+ATP, n = 131), and Group 4 (PVI + 30min+ATP, n = 135). The primary endpoint was freedom from AF. Repeat mapping to assess for late pulmonary vein (PV) reconnection was performed in patients who remained AF-free for >3 years (n = 46) and in those who had repeat ablation for AF recurrence (n = 82). During initial procedure, acute PV reconnection was observed in 33%, 26%, and 42% of patients in Groups 2, 3, and 4, respectively. At 36 months, no significant differences in freedom from AF recurrence were observed among all four groups (55%, 61%, 50%, and 62% for Groups 1, 2, 3, and 4, respectively; P = 0.258). Late PV reconnection was commonly observed, with a similar incidence between patients with and without AF recurrence (74% vs. 83%; P = 0.224).

Conclusion: Although PVI remains the cornerstone for AF ablation, intraprocedural techniques to assess for PV reconnection did not improve long-term success. Patients without AF recurrence after 3 years exhibited similarly high rates of PV reconnection as those that underwent repeat ablation for AF recurrence. The therapeutic mechanisms of AF ablation may not be solely predicated upon durable PVI.
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April 2020

The complete chloroplast genome of and its phylogenetic analysis.

Mitochondrial DNA B Resour 2019 Oct 21;4(2):3667-3668. Epub 2019 Oct 21.

Hainan Academy of Ocean and Fisheries Sciences, Haikou, People's Republic of China.

Complete chloroplast genome of was obtained in this work. Circular mapping revealed that the complete chloroplast sequences of was 176,748 bp in length and had an overall GC content of 38.3%, encoded 132 genes which contained 86 protein-coding genes (PCGs), 38 transfer RNA genes (tRNA) and 8 ribosomal RNA genes (rRNA). The phylogenetic tree shows that had a closer relationship with in Hydrocharitaceae and its analysis will help better understand the evolution of Alismatales species.
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October 2019

Investigating the synergetic dispersing effect of hydrolyzed biomacromolecule Cellulase and SDS on CuPc pigment.

Colloids Surf B Biointerfaces 2019 Dec 10;184:110568. Epub 2019 Oct 10.

Textile and Garment College, Chemical Engineering College of Qingdao University, Qingdao 266071, China; Collaborative Innovation Center for Eco-Textiles of Shandong Province, State Key Laboratory of Bio-Fibers and Eco-Textiles, Qingdao University, Qingdao 266071, China. Electronic address:

In this paper, the dispersion performance of biomacromolecule hydrolyzed cellulase from Trichoderma reesei on copper phthalocyanine (CuPc) pigment was first studied. The effect of hydrolysis time, cellulase concentration and environmental pH on the dispersion performance was investigated by particle size distribution and suspension transmittance measurement. The hydrolysis degree of cellulase was determined by FTIR, XRD, UV-vis and fluorescence spectra, potential and particle size analysis, respectively. Subsequently, the hydrolyzed cellulase was combined with sodium dodecyl sulfate (SDS) for acquiring better CuPc suspension based on their synergetic effects on dispersion. The optimal mass ratio of hydrolyzed cellulase to SDS was found to be 1:9. The resulting CuPc dispersion by this hydrolyzed cellulase/SDS composite was characterized by FTIR, TG, TEM, XRD analysis, respectively. This study demonstrated that there were strong interactions between hydrolyzed cellulase and SDS to result in synergistic dispersing effect on CuPc for better stability.
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December 2019

Upgrade to his bundle pacing in pacing-dependent patients referred for pulse generator change: Feasibility and intermediate term follow up.

Int J Cardiol 2018 06;260:88-92

Department of Cardiology, Sir Run Run Shaw Hospital, College of Medicine, Zhejiang University, No. 3 Qingchun East Road, Hangzhou 310016, Zhejiang, People's Republic of China. Electronic address:

Background: Right ventricular pacing (RVP) is associated with an increased incidence of heart failure and may impair cardiac function. Permanent His bundle pacing (HBP) has the potential to physiologically preserve and prevent cardiac dysfunction. This study was to evaluate the feasibility and intermediate follow-up results of upgrade to HBP implantation in patients referred for pulse generator change with long term RVP.

Methods: Twelve of 14 pacing dependent patients who were referred for pulse generator exchange underwent upgrade into HBP successfully in our center. QRS duration, New York Heart Association (NYHA) functional class, echocardiography, use of diuretics and lead parameters were measured at baseline and during the follow-up.

Results: Among the 12 patients attempted (mean age, 70.8 ± 8.9 years, 75% males) successfully, the average ejection fraction (EF) was 52.2 ± 11.2%. Nine of 12 patients underwent upgrade to HBP, and three patients with EF < 40% underwent HBP and biventricular pacing (BVP) as well. A significant reduction in mean QRS duration was observed compared with pre-implantation, from 157.8 ± 13.3 ms to 109.3 ± 16.9 ms (p < 0.001). After 6 months follow-up period, median NYHA functional class was improved from 2.7 ± 0.6 to 1.8 ± 0.6 (p = 0.007) and left ventricular internal diastolic diameter (LVIDd) was reduced from 5.5 ± 0.4 cm to 5.3 ± 0.3 cm (p = 0.03).

Conclusions: HBP improves heart failure symptoms with preserved EF by long term RVP. Permanent HBP is feasible and safe for upgrade in patients with long term RVP irrespective of LVEF.
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June 2018

Characterization of the epicardial substrate for catheter ablation of Brugada syndrome.

Heart Rhythm 2016 11 22;13(11):2151-2158. Epub 2016 Jul 22.

Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, People's Republic of China. Electronic address:

Background: Catheter ablation in the right ventricular outflow tract (RVOT) may modify the electrophysiologic substrate for recurrent ventricular tachycardia/ventricular fibrillation (VT/VF) in patients with Brugada syndrome (BrS).

Objective: The purpose of this study was to investigate the mechanism and arrhythmogenic substrate of VT/VF and to evaluate the long-term outcomes of catheter ablation in patients with BrS.

Methods: Eleven consecutive patients with BrS referred to 2 academic medical centers underwent combined epicardial-endocardial electroanatomic mapping. Catheter ablation was performed in regions of localized conduction slowing. Transmural dispersion of late activation was calculated as the difference between the latest activation between epicardium and endocardium, and low-voltage areas were analyzed.

Results: Eleven patients met diagnostic criteria for BrS (spontaneous type 1, n = 9; Na channel provocation = 2). All patients were found to have a localized region in the anterior epicardial RVOT with conduction slowing evidenced by prolonged electrogram duration (78.79 ± 19.87 ms vs 58.93 ± 10.11 ms in epicardial right ventricle, and 59.87 ± 12.61 ms in endocardial RVOT, P <.005, respectively) with variable low voltage (0.97 ± 0.48 mV; median scar area 19.8 ± 25.9 cm). Epicardial ablation resulted in normalization of spontaneous type 1 Brugada ECG pattern in all patients, and 73% were free from VT/VF at 25 ± 11 months.

Conclusion: Prolonged electrograms localized to epicardial RVOT with variable low voltage were identified in all patients with BrS. J-point and ST-segment elevation correlated with greater transmural dispersion of late activation and was independent of total low-voltage area. Despite normalization of spontaneous type 1 pattern in all patients after ablation, recurrence was still observed, suggesting the implantable cardioverter-defibrillator as the cornerstone therapy for BrS.
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November 2016

Macroreentrant Loop in Ventricular Tachycardia From the Left Posterior Fascicle: New Implications for Mapping and Ablation.

Circ Arrhythm Electrophysiol 2016 09;9(9)

From the Department of Cardiology, Sir Run Run Shaw Hospital, School of Medicine, Zhejiang University, Zhejiang, P.R. China (Q.L., R.J., L.Y., S.C., J.Z., C.J.); and Heart Institute, Cedars Sinai Medical Center, Los Angeles, CA (Q.L., M.S., A.E., A.A.S., E.C., S.S.C., X.W.).

Background: The underlying mechanisms of reentry during left posterior fascicular ventricular tachycardia (LPF-VT) remain unclear. The purpose of this study is to describe the components of LPF-VT reentry circuit and their electrophysiological properties.

Methods And Results: Fourteen consecutive patients with LPF-VT underwent electrophysiology study and radiofrequency ablation. Via a multipolar electrode catheter placed from a retrograde aortic approach, a sharp inflection, high-frequency potential (P1) was detected in 9 patients (64%). The ranges of length and velocity of recorded P1 were 9 to 30 mm and 0.5 to 1.2 mm/ms, respectively. Macroreentry involving the ventricular myocardium was confirmed to be the mechanism in all patients by premature ventricular stimuli delivery or entrainment of LPF-VT with progressive fusion, or both. During LPF-VT, the earliest left posterior fascicle (LPF, P2) was considered to be the site of connection between P1 and P2, and the site of the earliest P2 along the left posterior ventricular septum correlated well with the His-ventricular interval during tachycardia. Radiofrequency ablation focused on the P1 potentials (9 patients with a recorded P1) or earliest P2 (5 patients without a recorded P1) was successful in all 14 patients. After 4.5±3.0 months of follow-up, no patients had recurrence of LPF-VT.

Conclusions: The LPF-VT macroreentrant loop involves the ventricular myocardium, a part of the LPF, a slow conduction zone, and in certain cases, a specially conducting P1 fiber. The His-ventricular interval during LPF-VT correlates with multiple electrophysiological measures and is a useful marker for identification of the optimal ablation site.
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September 2016