Publications by authors named "Michael Mok"

Objective: To assess whether in adults with dyslipidemia, statins reduce cardiovascular events, mortality, and adverse effects when compared to fibrates.

Methods: Systematic review and meta-analysis of head-to-head randomized trials of statin and fibrate monotherapy. MEDLINE, EMBASE, Cochrane, WHO International Controlled Trials Registry Platform, and ClinicalTrials.

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Introduction: The risk of liver injury in patients with atrial fibrillation (AF) using nonvitamin K antagonist oral anticoagulants (NOACs) has not been previously examined using liver function tests as the primary outcome in the real-world setting. This study assessed the association between NOACs (dabigatran, rivaroxaban, and apixaban) and warfarin and the risk of liver injury, as defined by laboratory tests.

Methods: Patients newly diagnosed with AF and prescribed NOACs or warfarin between 2010 and 2016, identified using the Hong Kong Clinical Database and Reporting System, were matched on age, sex, health status scores, comorbidities, and medications by propensity score on a 1:1 ratio.

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Large regions with seagrass meadows have been discovered on Dongsha Atoll located in the South China Sea. The aim of this study is the estimation of acoustic propagation loss in the frequency range of individual bubble resonance due to the gas content of seagrass in seagrass meadows. Specifically, this study seeks to (a) investigate the attenuation of the mid-frequency (2-8 kHz) signal induced by the gas content in a seagrass meadow and (b) present the diurnal variation of sound attenuation.

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Background: Dual antiplatelet therapy (DAPT) with aspirin plus clopidogrel is used for stroke prevention in patients with atrial fibrillation (AF) who refuse to take use oral anticoagulants (OACs). However, clinical data comparing these treatments are limited.

Objective: The purpose of this study was to compare the clinical outcomes between DAPT and OAC in patients with AF.

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Background And Aims: Clinical practice guidelines recommend specific statin doses for the primary and secondary prevention of cardiovascular disease. Little is known about how statin utilization and dosing have evolved over time in Hong Kong. The aim of this study was to describe trends in statin prevalence, initiation, and dosing from 2004 to 2015.

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Transcatheter aortic valve implantation (TAVI) is an effective intervention for severe aortic stenosis in patients at intermediate or high surgical risk, but damage to the native conduction system such as left bundle branch block (LBBB) may offset its benefits. New onset LBBB is associated with a higher risk of cardiovascular morbidity and mortality. His-bundle pacing (HBP) may be useful to treat TAVI-induced LBBB but has yet to be reported.

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Balloon aortic valvuloplasty (BAV) intervention is used as destination therapy or as a bridge to percutaneous or surgical aortic valve intervention. BAV is traditionally performed via a transfemoral approach; however, this may not be feasible in all patients due to peripheral vascular disease. We present a case of BAV performed via bilateral transradial access utilizing simultaneous deployment of two angioplasty balloons.

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Background: Women with atrial fibrillation are at a higher risk of stroke, despite treatment with warfarin. It is unclear if women treated with direct oral anticoagulants (DOACs) have better clinical outcomes, especially when considering the quality of anticoagulation control of warfarin.

Objectives: This study compared the effectiveness and safety outcomes of DOACs versus warfarin in men and women with stratifications for anticoagulation control.

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Body composition (fat mass [FM] and skeletal muscle mass [SMM]) predicts clinical outcomes. In particular, loss of SMM (sarcopenia) is associated with frailty and mortality. There are no data on the prevalence and impact of FM and SMM in patients undergoing transcatheter aortic valve implantation (TAVI).

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Background & Aims: Use of dabigatran, an inhibitor of thrombin, increases the risk of gastrointestinal bleeding (GIB). However, it is not clear whether gastroprotective agents (GPAs) prevent GIB in dabigatran users. We investigated the risk of GIB and the role of gastroprotective agents (including proton pump inhibitors and histamine type-2-receptor antagonists) in patients using dabigatran.

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Objectives: This study sought to determine the effects of chronic obstructive pulmonary disease (COPD) on clinical outcomes in patients undergoing transcatheter aortic valve implantation (TAVI) and to determine the factors associated with worse outcomes in COPD patients.

Background: No data exist on the factors determining poorer outcomes in COPD patients undergoing TAVI.

Methods: A total of 319 consecutive patients (29.

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The photosymbiotic ascidian fauna at Changi Beach, Pulau Semakau, Sentosa and St. John's Island, Singapore were surveyed. A total of five species, Diplosoma simile, Lissoclinum bistratum, Lissoclinum punctatum, Lissoclinum timorense and Trididemnum cyclops, were recorded, with Lissoclinum timorense and Trididemnum cyclops being newly recorded in Singapore.

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Objectives: This study sought to evaluate, through a systematic review of the published data, the main baseline characteristics, management, and clinical outcomes of patients suffering coronary obstruction as a complication of transcatheter aortic valve implantation (TAVI).

Background: Very few data exist on coronary obstruction after TAVI.

Methods: Studies published between 2002 and 2012, with regard to coronary obstruction as a complication of TAVI, were identified with a systematic electronic search.

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Objectives: The aim of this study was to demonstrate the first-in-human feasibility and short-term clinical outcomes with a new balloon-expandable transcatheter heart valve (THV).

Background: The SAPIEN 3 (S3) THV incorporates a paravalvular sealing system, an active 3-dimensional coaxial positioning catheter, and is compatible with a 14-F expandable sheath.

Methods: The S3 THV was implanted in 15 patients with symptomatic severe aortic stenosis via femoral arterial access.

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Transcatheter aortic valve implantation with the self-expandable CoreValve (CV) and the balloon-expandable Edwards SAPIEN (ES) bioprostheses has been widely used for the treatment of severe aortic stenosis. However, a direct comparison of the hemodynamic results associated with these 2 prostheses is lacking. The aim of the present study was to compare the hemodynamic performance of both bioprostheses.

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Atrial fibrillation (AF) is a common co-morbidity among patients undergoing Transcatheter Aortic Valve Implantation (TAVI). Only recently have the clinical outcomes of patients with chronic or new-onset AF after TAVI been reported. The absence of clinical trials focusing on this cohort of patients has resulted in the lack of evidence based clinical guidelines.

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Objectives: This study evaluated the predictive factors and prognostic value of new-onset persistent left bundle branch block (LBBB) in patients undergoing transcatheter aortic valve implantation (TAVI) with a balloon-expandable valve.

Background: The predictors of persistent (vs. transient or absent) LBBB after TAVI with a balloon-expandable valve and its clinical consequences are unknown.

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Acute coronary obstruction is one of the most feared complications associated with transcatheter aortic valve-in-valve implantation. Strategies for assessing the risk of coronary occlusion during these procedures as well as preventive measures are discussed.

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Objective: To determine the impact of perioperative thoracic epidural analgesia (TEA) on acute and late outcomes following transapical transcatheter aortic valve implantation (TA-TAVI).

Patients And Intervention: A total of 135 consecutive patients who underwent TA-TAVI were included. All patients received catheter-based pain control, either via TEA (TEA group, n=74) or intercostal local analgesia with a catheter placed at the surgical incision site (non-TEA group, n=61), depending on the preference of the anaesthesiologist responsible for the case.

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In transcatheter aortic valve implantation procedures using balloon-expandable valves, the valve is deployed by rapid balloon inflation within a short period of rapid ventricular pacing. This system and deployment technique is generally considered to be nonrepositionable. We illustrate with two cases (transapical and transfemoral) the possibility to partially reposition the valve during its deployment if a slow balloon inflation technique were employed-a technique that may minimize the risk of valve mal-positioning and its attendant complications.

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Objectives: This study sought to evaluate the predictive factors, effects, and safety of balloon post-dilation (BPD) for the treatment of significant paravalvular aortic regurgitation (AR) after transcatheter aortic valve implantation (TAVI).

Background: Very few data exist on BPD after TAVI with a balloon-expandable valve.

Methods: A total of 211 patients who underwent TAVI with a balloon-expandable valve were included.

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Transaortic transcatheter aortic valve implantation (TAo-TAVI) has been recently proposed as an alternative to transapical (TA) and transfemoral (TF) approach. We now discuss a technical issue associated with TAo-TAVI related to the use of a delivery system dedicated to the antegrade TA approach. The potential solutions to this issue as well as the potential advantages of the TAo approach are discussed.

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