Gabriel W K Yip

Hong Kong Hospital Authority, Hong Kong, Hong Kong

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Publications (58)416.87 Total impact

  • J. Wang · F. Fang · G. W. K. Yip · J. E. Sanderson · W. Feng · P. W. Lee · C. M. Yu · Y. -Y. Lam

    No preview · Conference Paper · Sep 2014
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    ABSTRACT: AimsWe assessed the left ventricular (LV) and peripheral performance at rest and during exercise in healthy and heart failure subjects with normal ejection fraction (HFNEF) or with reduced ejection fraction (HFREF).Methods All subjects received echocardiography at rest and with bicycle Ergometer exercise. The exercise images for two-dimensional speckle tracking were acquired with submaximal heart rate of 90–100 beats/min, while images for M-mode and tissue Doppler imaging were stored with attainment of >85% of predicted heart rate.ResultsA total of 80 HFNEF, 50 HFREF and 50 controls were studied. There was progressive decrease of two-dimensional global circumferential, radial and longitudinal strains (GCS, GRS and GLS), M-mode and tissue Doppler imaging long-axis parameters from controls, HFNEF to HFREF patients (all P < 0.05) at rest and on exercise. The degree of exercise-induced, long-axis augmentation (GLS and M-mode long axis excursion) decreased progressively from controls, HFNEF to HFREF subjects (all P < 0.05), while the increase in GCS and GRS was similar in all groups. The ventricular–arterial coupling ratio did not change in HFREF but reduced in HFNEF and controls during exercise (P < 0.01). All subjects had a similar resting heart rate, but patients exhibited chronotropic non-competence during exercise (P < 0.001).Conclusions Ventricular and peripheral dysfunction was evident in HFNEF at rest and deteriorated during exercise. The HFNEF patients had significantly impaired long-axis augmentation at stress that was intermediate between HFREF patients and controls. These findings have relevance to generation of symptoms on exercise in both HFNEF and HFREF.
    Full-text · Article · Aug 2014 · European Journal of Heart Failure
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    ABSTRACT: We aimed to establish community-based normal reference values of 24-h ambulatory blood pressure monitoring (ABPM) for Chinese children and adolescents. Furthermore, we investigated how excluding overweight children affects BP percentiles and compared them with German references. In this territory-wide cross-sectional prospective cohort study, 1445 Hong Kong Chinese children and adolescents aged 8-17 years with body height between 119 and 185 cm were recruited. Their ABPM assessment was performed using validated arm oscillometric recorders (A&D TM-2430) and complied with American Heart Association's recommendations. The reference tables were constructed using the LMS method to normalize skewed distribution of ABP data to sex and age or height. The ambulatory BP was higher among boys and the difference between boys and girls progressively widened with age. An increasing trend in daytime and night-time SBP and DBP with age and height was observed in both sexes. The age-specific and sex-specific 95th percentiles from nonoverweight children (n = 1147; 79%) were lower than the whole cohort by up to 2.5 and 1 mmHg for SBP and DBP, respectively. In comparison, our overall and nonoverweight reference standards were generally higher than corresponding German references. The study provides ambulatory BP standards for Chinese children, with sex-related age-specific and height-specific percentiles. Further longitudinal studies are required for investigating its clinical utility in Chinese.
    No preview · Article · Jan 2014 · Journal of Hypertension
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    ABSTRACT: Background. T-box expressed in T cells (TBET) and guanine adenine thymine adenine sequence-binding protein 3 (GATA3) play important roles in the differentiation of Th1 and Th2 subsets, which contributes to the progression of acute coronary syndrome (ACS). Objective. This study aimed to investigate the temporal change of TBET/GATA3 mRNA ratio in ACS. Methods. Thirty-three patients suspected of ACS with symptom onset within 24 hours were recruited. Blood samples were taken after arrival at the emergency department and at hourly intervals until the 6th hour. The mRNA expressions of TBET and GATA3 were quantified by a real-time RT-qPCR. Results. The TBET/GATA3 mRNA ratio was elevated dramatically in patients with acute myocardial infarction (AMI) and exhibited biphasic M-shaped release kinetics with two distinct peaks. The ratio was elevated 2 hours after symptom onset, dropped to the lowest level at 10 hours, and rose to the second peak at 14 hours. A similar biphasic M-shaped curve was observed in AMI patients with blood samples taken prior to any intervention. Conclusions. The TBET/GATA3 mRNA ratio was elevated in AMI patients throughout most of the first 20 hours after symptom onset. The biphasic M-shaped release kinetics was more likely to reflect pathophysiological changes rather than treatment effects.
    Full-text · Article · Sep 2013 · Disease markers
  • Q Shang · G W K Yip · L S Tam · Q Zhang · J E Sanderson · Y Y Lam · C M Li · T Wang · E K M Li · C M Yu
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    ABSTRACT: Left ventricular (LV) diastolic dysfunction has been reported in both active and inactive systemic lupus erythematosus (SLE) patients without clinical evidence of cardiovascular disease. However, the relationship between the long-term inflammatory burden reflected by the SLICC/ACR damage index and LV diastolic function has not been studied. Eighty-two SLE patients and 82 controls matched for age, sex, body mass index, blood pressure and heart rate underwent echocardiography with tissue Doppler imaging (TDI). LV diastolic function was estimated by the myocardial early diastolic velocity (E') at the lateral annulus. There were 51 patients (62.2%) with nephritis, 23 patients (28.0%) with hypertension, 21 patients (25.6%) with vasculitis, 16 patients (19.5%) with pulmonary hypertension, 4 patients (4.9%) with cerebrovascular disease and 2 patients (2.4%) with diabetes mellitus. Sixty-two patients (75.6%) were taking prednisone and 35 patients (42.7%) used a immunosuppressant. Forty-five patients (54.8%) had active disease and suffered from disease-related end-organ damage. Patients with SLICC/ACR damage index ≥1 had more evidence of LV diastolic dysfunction with lower lateral annulus E' (9.6 ± 3.4 vs 12.9 ± 3.5 cm/s, p < 0.001) than those without. In addition, the proportion of patients with abnormal LV myocardial relaxation (defined as lateral E' < 10.0 cm/s) (51.1% vs 16.2%, χ(2) = 10.8, p = 0.001) were significantly higher. Multivariate analysis showed that the SLICC/ACR damage index ≥1 was independently associated with LV diastolic dysfunction (OR = 3.80, 95%CI: 1.21-11.95, p = 0.023) after adjusting for hypertension, disease duration and medical therapy. This may suggest that the overall inflammatory burden in SLE, as reflected by SLICC/ACR damage index, is associated with the development of diastolic dysfunction in SLE patients.
    No preview · Article · May 2012 · Lupus
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    ABSTRACT: Left atrial appendage (LAA) is the main source of left atrial thrombus that causes stroke in patients with non-valvular atrial fibrillation (NVAF). This study reported the initial safety, feasibility, and 1-yr clinical outcomes following AMPLATZER cardiac plug (ACP) implantation in Asia-Pacific region. Twenty NVAF patients (16 males, age 68 ± 9 yr) with high risk for developing cardioembolic stroke (CHADS(2) score: 2.3 ± 1.3) and contraindications to warfarin received ACP implants from June 2009 to May 2010. Patients received general anesthesia (n = 9) or controlled propofol sedation (n = 11) and the procedures were guided by fluoroscopy and transesophageal echocardiography (TEE). Clinical follow-up was arranged at 1 month and then every 3 months after implantation, whereas, a TEE was scheduled at 1 month upon completion of dual anti-platelet therapy. The LAA was successfully occluded in 19/20 patients (95%) at two Asian centers. One procedure was abandoned because of catheter-related thrombus formation. Other complications included coronary artery air embolism (n = 1) and TEE-attributed esophageal injury (n = 1). The median procedural and fluoroscopic times were 79 (IQR: 59-100) and 18 (IQR 12-27) minutes, respectively. The mean size of implant was 23.6 ± 3.1 mm. The average hospital stay was 1.8 ± 1.1 days. Follow-up TEE showed all the LAA orifices were sealed without device-related thrombus formation. No stroke or death occurred at a mean follow-up of 12.7 ± 3.1 months. Our preliminary data suggested LAA closure with ACP is safe, feasible with encouraging 1-yr clinical outcomes. Further large-scaled trials are needed to confirm the efficacy of this device.
    No preview · Article · Apr 2012 · Catheterization and Cardiovascular Interventions

  • No preview · Article · Feb 2012 · International journal of cardiology
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    ABSTRACT: To determine the relationship between in utero hyperinsulinemia and children's arterial stiffness at adolescence. Indices of arterial stiffness were measured using the SphygmoCor apparatus in 129 adolescents (42 offsprings of mother with gestational diabetes and 87 offsprings of mother with normal glucose tolerance during pregnancy) at 15 years of age. Adolescent of mothers with gestational diabetes had similar central aortic blood pressure, augmentation pressure (AP), augmentation index (AI), and carotid-femoral pulse wave velocity (PWV) as that of controls. However, both umbilical cord C-peptide and insulin levels correlated positively AI (R=0.28 and 0.24; p=0.011 and 0.035, respectively), and umbilical insulin level correlated positively with AP (R=0.25; p=0.025). The correlations were significant between umbilical cord C-peptide and AP (R=0.24; p=0.035) and AI (R=0.29; p=0.011) after adjustment for subjects' age, sex, body weight and height. Adolescents who had umbilical cord C-peptide levels at highest quartile (n=25), based on the reference ranges of the original cohort, had a significant greater PWV (5.26±0.12 m/s vs 4.98±0.12 m/s; p=0.0049) than those with C-peptide levels at the lower 3 quartiles (n=57) after adjustment for age, sex, body weight and height. In utero hyperinsulinemia appears to increase the offspring's arterial stiffness at early adolescence.
    No preview · Article · Nov 2011 · Diabetes research and clinical practice
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    ABSTRACT: To ascertain the effect of rosuvastatin on carotid atherosclerosis and arterial stiffness in patients with rheumatoid arthritis (RA). Fifty RA patients were randomized in a double-blind placebo-controlled trial to receive 10 mg rosuvastatin (n = 24) or placebo (n = 26). Patients were followed prospectively every 3 months for 12 months. Intima-media thickness (IMT), augmentation index (AIx), and subendocardial viability ratio (SEVR) were measured at baseline, 6 and 12 months. Rosuvastatin resulted in statistically significant reductions of total cholesterol (TC), low density lipoprotein cholesterol (LDL-C), apolipoprotein B (Apo B), and urate levels vs. placebo. However, rosuvastatin had no significant effect on changes in inflammatory markers, including C-reactive protein (CRP) levels [from 2.9 (1.4-11.0) to 3.1 (0.9-13.3) mg/L in the rosuvastatin group compared with from 5.8 (2.6-14.2) to 4.4 (1.2-12.3) mg/L in the placebo group]. Nonetheless, a significant improvement in the Disease Activity Score (DAS) and a reduction in fibrinogen level was observed at 6 and 12 months compared with baseline in the rosuvastatin group. The treatment group exhibited a significant increase in SEVR (from 157 ± 28% to 163 ± 33% in the rosuvastatin group compared with from 143 ± 18% to 143 ± 26% in the placebo group, p = 0.023), but no significant effect was observed in the changes in IMT and AIx. Our data suggest that rosuvastatin has a modest anti-inflammatory effect in RA patients with low disease activity in terms of reduction in DAS and fibrinogen level. Rosuvastastin may also improve subendocardial perfusion and lower the urate level.
    No preview · Article · Aug 2011 · Scandinavian journal of rheumatology
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    ABSTRACT: Right ventricular apex (RVA) pacing may have deleterious effects on left ventricular (LV) systolic function, but its impact on LV diastolic function has not been explored. Ninety-seven patients with sinus node dysfunction and ejection fraction (EF) ≥ 50% with permanent RVA pacing were randomly programmed to V-sense and V-pace modes and examined by echocardiography. Tissue Doppler imaging was employed to assess myocardial systolic velocity (S') and early diastolic velocity (E') at the mitral annulus. Systolic dyssynchrony was assessed using 12 LV segmental model (Ts-SD). Switching from V-sense to V-pace resulted in the worsening of both diastolic and systolic functions as shown by the decreased EF, reduced mean E' and S' velocities, as well as increase in LV volume and Ts-SD (all P< 0.001). Reduction of mean E' and S' of ≥ 1 cm/s occurred in 35 (36%) and 45 (46%) patients, respectively. In pre-defined subgroup analysis, only patients with pre-existing LV diastolic dysfunction had a significant reduction of mean E' and S' (both P< 0.001) even after age adjustment. Multivariate logistic regression analysis showed that independent factors for the reduction of mean E' ≥ 1 cm/s or mean S' ≥ 1 cm/s at V-pace were pre-existing LV diastolic dysfunction [odds ratio (OR): 4.735, P= 0.007 for E'; OR: 3.307, P= 0.022 for S'] and systolic dyssynchrony at V-pace (OR: 5.459, P= 0.007 for E'; OR: 2.725, P= 0.035 for S'). In patients with preserved EF, RVA pacing is associated with the deterioration of both LV diastolic and systolic functions, which is particularly obvious in those with pre-existing LV diastolic dysfunction and V-pace-induced systolic dyssynchrony.
    Preview · Article · Apr 2011 · European Heart Journal
  • Ming Dong · Bryan P Yan · James K Liao · Yat-Yin Lam · Gabriel W.K. Yip · Cheuk-Man Yu
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    ABSTRACT: The Rho/rho-kinase (ROCK) pathway has an important role in the pathogenesis of several cardiovascular diseases. The activation of ROCK is involved in the regulation of vascular tone, endothelial dysfunction, inflammation and remodeling. The inhibition of ROCK has a beneficial effect in a variety of cardiovascular disorders. Evidence from animal models and from clinical use of ROCK inhibitors, such as Y-27632, fasudil and statins (i.e. pleiotropic effects), supports the hypothesis that ROCK is a potential therapeutic target. This review provides a current understanding of the role of ROCK pathway in the regulation of vascular function and the use of ROCK inhibitors in the treatment of cardiovascular disorders.
    No preview · Article · Aug 2010 · Drug discovery today
  • Gabriel W. K. Yip · John E. Sanderson

    No preview · Article · May 2010 · Heart (British Cardiac Society)
  • Q. Zhang · Q. Shang · G. W. K. Yip · Y. M. Liu · R. J. Li · Y. Y. Lam · A. P. W. Lee · C. M. Yu

    No preview · Conference Paper · Feb 2010
  • G.W.K. Yip · J E Sanderson

    No preview · Article · Dec 2009 · Heart (British Cardiac Society)
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    ABSTRACT: This study aimed to evaluate the impact of cardiac contractility modulation (CCM) on left ventricular (LV) size and myocardial function. CCM is a device-based therapy for patients with advanced heart failure. Previous studies showed that CCM improved symptoms and exercise capacity; however, comprehensive assessment of LV structure, function, and reverse remodeling is not available. Thirty patients (60 + or - 11 years, 80% male) with New York Heart Association (NYHA) functional class III heart failure, ejection fraction <35%, and QRS <120 ms were assessed at baseline and 3 months. LV reverse remodeling was measured by real-time 3-dimensional echocardiography. Using tissue Doppler imaging, the peak systolic velocity (Sm) and peak early diastolic velocity (Em) were calculated for LV function, while the standard deviation of the time to peak systolic velocity (Ts-SD) and the time to peak early diastolic velocity (Te-SD) were calculated for mechanical dyssynchrony. LV reverse remodeling was evident, with a reduction in LV end-systolic volume by -11.5 + or - 10.5% and a gain in ejection fraction by 4.8 + or - 3.6% (both p < 0.001). Myocardial contraction was improved in all LV walls, including sites remote from CCM delivery (all p < 0.05); hence, the mean Sm of 12 (2.2 + or - 0.6 cm/s vs. 2.5 + or - 0.7 cm/s) or 6 basal LV segments (2.5 + or - 0.6 cm/s vs. 3.0 + or - 0.7 cm/s) were increased significantly (both p < 0.001). In contrast, CCM had no impact on regional or global Em (2.9 + or - 1.3 cm/s vs. 2.9 + or - 1.1 cm/s), whereas Ts-SD (28.2 + or - 11.2 ms vs. 27.9 + or - 12.7 ms) and Te-SD (30.0 + or - 18.3 ms vs. 30.1 + or - 20.7 ms) remained unchanged (all p = NS). Mitral regurgitation was reduced (22 + or - 14% vs. 17 + or - 15%, p = 0.02). Clinically, there was improvement of NYHA functional class (p < 0.001) and 6-min hall walk distance (p = 0.015). A 24-h Holter monitor showed that premature ventricular contractions were not increased during CCM. CCM improves both global and regional LV contractility, including regions remote from the impulse delivery, and may contribute to LV reverse remodeling and gain in systolic function. Such improvement is unrelated to diastolic function or mechanical dyssynchrony.
    No preview · Article · Dec 2009 · JACC. Cardiovascular imaging
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    ABSTRACT: Arterial stiffness is an important index for cardiovascular events. The objective of this study is to examine possible parameters related to arterial stiffness that can be estimated during simple arm movements. An experiment was conducted on 32 subjects divided into two groups, one with an age of 26+/-4 years old, and the other 61+/-9. The pulse transit time measured from electrocardiogram to finger photoplethysmogram (PPG) and the amplitude of PPG were calculated beat-to-beat for the subjects while they had their arms lowered. The results of the study showed that the ratio between percentage changes in PTT and finger height are significantly different for the two groups of subjects with different age and health conditions, indicating that parameters can be potentially extracted from this procedure to represent the difference in arterial stiffness of the two groups of subjects.
    No preview · Article · Sep 2009 · Conference proceedings: ... Annual International Conference of the IEEE Engineering in Medicine and Biology Society. IEEE Engineering in Medicine and Biology Society. Conference
  • John E Sanderson · Gabriel W K Yip

    No preview · Article · Feb 2009 · BMJ (online)
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    ABSTRACT: The optimal left ventricular (LV) pacing site for cardiac resynchronization therapy (CRT) is unclear. The current study aims to explore the clinical significance of LV lead concordance to delayed contraction segment in CRT. Concordant LV lead position was defined as the lead tip located by fluoroscopy at or immediately adjacent to the LV segment with latest contraction determined by tissue Doppler imaging. Echocardiographic and clinical outcomes among 101 consecutive patients with or without concordant LV lead positions were compared. There was no significant difference in changes in LV volumes and clinical parameters between patients with concordant (n = 46) or nonconcordant (n = 55) LV lead positions at 3 and 6 months. In multivariate analysis, the baseline asynchrony index (beta= 1.092, 95% CI: 1.050-1.114; P < 0.001), but not LV lead concordance, was the only independent predictor of LV reverse remodeling. By Cox regression analysis, ischemic etiology, and LV reverse remodeling, but not LV lead concordance, were independent predictors of mortality (beta= 2.475, 95% CI: 1.183-5.178; P = 0.016, and beta= 0.272, 95% CI: 0.130-0.567; P < 0.001, respectively), cardiovascular hospitalization (beta= 1.551, 95% CI: 1.032-2.333; P = 0.035, and beta= 0.460, 95% CI: 0.298-0.708; P < 0.001, respectively), and heart failure hospitalization (beta= 0.486, 95% CI: 0.320-0.738; P = 0.001 for LV reverse remodeling). LV lead concordance to the delayed contraction segment may not be a major determining factor for favorable echocardiographic and clinical outcomes after CRT.
    No preview · Article · Dec 2008 · Journal of Cardiovascular Electrophysiology
  • Jeffrey W H Fung · Gabriel W K Yip · Cheuk-Man Yu

    No preview · Article · Aug 2008 · Heart (British Cardiac Society)
  • Qing Zhang · J W-H Fung · Gabriel W. K. Yip · J Y-S Chan · A P-W Lee · Y-Y Lam · L-W Wu · E B Wu · C-M Yu
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    ABSTRACT: To evaluate whether short-axis function plays a part in determining left ventricular (LV) geometric and functional improvement after cardiac resynchronisation therapy (CRT). 39 patients who received CRT were enrolled. 2D speckle tracking echocardiography was performed at baseline and three months after CRT to assess mean systolic circumferential (epsilon-circum), radial (epsilon-radial) and longitudinal (epsilon-long) strain and torsion. Responders of reverse remodelling (n = 21) had higher baseline mean epsilon-circum than non-responders (p<0.05), who also had improvement in mean epsilon-circum and mean epsilon-radial (both p<0.05) after CRT. Also, the increase in mean epsilon-circum correlated with increase in ejection fraction (r = 0.57, p<0.001) and decrease in mid-cavity width (r = -0.52, p = 0.001). A baseline mean epsilon-circum of >or=6.5% predicted a gain in ejection fraction >or=5%, with a sensitivity of 73% and a specificity of 71%. The baseline epsilon-long was not different between the two groups, and remained unchanged after CRT. The torsion did not improve in responders, but was worsened in non-responders (p<0.05). The improvement of LV short-axis function but not long-axis function or torsion contributes to the improvement in LV global function and geometry at three-month follow up. A relatively preserved mean epsilon-circum of >or=6.5% might be useful to predict favourable responses after CRT.
    No preview · Article · Jul 2008 · Heart (British Cardiac Society)

Publication Stats

2k Citations
416.87 Total Impact Points


  • 2014
    • Hong Kong Hospital Authority
      Hong Kong, Hong Kong
  • 2001-2014
    • The Chinese University of Hong Kong
      • Department of Medicine and Therapeutics
      Hong Kong, Hong Kong
  • 2007
    • Prince of Wales Hospital, Hong Kong
      Chiu-lung, Kowloon City, Hong Kong
  • 2004
    • Mayo Clinic - Rochester
      • Department of Cardiovascular Diseases
      Rochester, Minnesota, United States
  • 2003
    • Hong Kong SAR Government
      Hong Kong, Hong Kong