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Sahlén AO, Jiang H, Lau YH, Cuenza L, Cader FA, Al-Omary M, Surunchupakorn P, Ho KH, Sung J, Lee D, Honda S, Tan Wei Chieh J, Yap J. Direct Oral Anticoagulation Versus Warfarin in Left Ventricular Thrombus: Pooled Analysis of Randomized Controlled Trials. J Clin Pharmacol 2023; 63:1101-1107. [PMID: 37139934 DOI: 10.1002/jcph.2267] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2023] [Accepted: 05/02/2023] [Indexed: 05/05/2023]
Abstract
Patients with impaired left ventricular (LV) function can develop LV thrombus, a potentially life-threatening condition due to risk of stroke and embolization. Conventional treatment with vitamin K antagonists (VKAs; e.g., warfarin) puts patients at risk of bleeding, and the use of direct oral anticoagulants (DOACs) appears promising, although data are scant. We searched the published English language literature for randomized controlled trials (RCTs) comparing DOACs with VKAs in LV thrombus. End points were failure to resolve, thromboembolic events (stroke, embolism), bleeding, or any adverse event (composite of thromboembolism or bleeding), or all-cause death. Data were pooled and analyzed in hierarchical Bayesian models. In three eligible RCTs, 141 patients were studied during an average of 4.6 months (53.8 patient-years; n = 71 assigned to DOAC, n = 70 assigned to VKA). A similar number of patients in each treatment arm demonstrated failure to resolve (DOAC: 14/71 vs. VKA: 15/70) and death events (3/71 vs. 4/70). However, patients on DOACs suffered fewer strokes/thromboembolic events (1/71 vs. 7/70; log odds ratio [OR], -2.02 [95% credible interval (CI95 ), -4.53 to -0.31]) and fewer bleeding events (2/71 vs. 9/70; log OR, -1.62 [CI95 , -3.43 to -0.26]), leading to fewer patients on DOACs with any adverse event versus VKAs (3/71 vs. 16/70; log OR, -1.93 [CI95 , -3.33 to -0.75]). In conclusion, pooled analysis of RCT data favors DOACs over VKAs in patients with LV thrombus in terms of both efficacy and safety.
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Affiliation(s)
- Anders Olof Sahlén
- National Heart Centre Singapore, Singapore, Singapore
- Duke-NUS Medical School, Singapore, Singapore
- Karolinska Institutet, Huddinge, Sweden
| | - Haowen Jiang
- Lee Kong Chian School of Medicine, Singapore, Singapore
| | - Yee How Lau
- National Heart Centre Singapore, Singapore, Singapore
| | - Lucky Cuenza
- Philippines Heart Center, Quezon City, Philippines
| | - F Aaysha Cader
- Ibrahim Cardiac Hospital and Research Institute, Dhaka, Bangladesh
| | | | | | - Ka Hei Ho
- Tuen Mun Hospital, Hong Kong, Hong Kong
| | | | - Derek Lee
- Queen Elizabeth Hospital, Hong Kong, Hong Kong
| | - Satoshi Honda
- National Cerebral and Cardiovascular Centre, Suita, Osaka, Japan
| | - Jack Tan Wei Chieh
- National Heart Centre Singapore, Singapore, Singapore
- Duke-NUS Medical School, Singapore, Singapore
| | - Jonathan Yap
- National Heart Centre Singapore, Singapore, Singapore
- Duke-NUS Medical School, Singapore, Singapore
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Lee SYA, Loh PH, Lau YH, Jiang Y, Liew BW, Lim PZY, Rastogi S, Tan WCJ, Ho HH, Yeo KK. Impact of COVID-19 pandemic early response measures on myocardial infarctions and acute cardiac care in Singapore. Int J Qual Health Care 2023:7156526. [PMID: 37148306 DOI: 10.1093/intqhc/mzad023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2023] [Revised: 03/03/2023] [Accepted: 04/19/2023] [Indexed: 05/08/2023] Open
Abstract
BACKGROUND The COVID-19 pandemic impacted acute myocardial infarction (AMI) attendances, ST-elevation myocardial infarction (STEMI) treatment and outcomes. We collated data from majority of primary percutaneous coronary intervention (PPCI)-capable public healthcare centres in Singapore to understand the initial impact COVID-19 had on essential time-critical emergency services. We present data comparisons from 'Before Disease Outbreak Response System Condition (DORSCON) Orange', 'DORSCON Orange to start of circuit breaker (CB)' and during the first month of 'CB'. METHODS We collected aggregate numbers of weekly elective PCI from 4 centres and AMI admissions, PPCI and in-hospital mortality from 5 centres. Exact door-to-balloon (DTB) times were recorded for 1 centre; another 2 reported proportions of DTB times exceeding targets. RESULTS Median weekly elective PCI cases significantly decreased from 'Before DORSCON Orange' to 'DORSCON Orange to start of CB' (34 vs. 22.5, p=0.013).Median weekly STEMI admissions and PPCI did not change significantly. In contrast, the median weekly NSTEMI admissions decreased significantly from 'Before DORSCON Orange' to 'DORSCON Orange to start of CB' (59 vs. 48, p=0.005) and was sustained during CB (39 cases).Exact DTB times reported by 1 centre showed no significant change in the median. Out of 3 centres, 2 reported significant increases in the proportion that exceeded DTB targets.In-hospital mortality rates remained static. CONCLUSION In Singapore, STEMI and PPCI rates remained stable, while NSTEMI rates decreased during DORSCON and CB. The SARS experience may have helped prepare us to maintain essential services such as PPCI during periods of acute healthcare resource strain. However, data must be monitored and increased pandemic preparedness measures must be explored to ensure that AMI care is not adversely affected by continued COVID fluctuations and future pandemics.
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Affiliation(s)
- Shan Yin Audry Lee
- National Heart Centre, Singapore, Department of Cardiology, 5 Hospital Drive, Singapore 169609
| | - Poay Huan Loh
- National University Heart Centre, Singapore, Department of Cardiology, 5 Lower Kent Ridge Road, Singapore 119074
| | - Yee How Lau
- National Heart Centre, Singapore, Department of Cardiology, 5 Hospital Drive, Singapore 169609
| | - Yilin Jiang
- National Heart Centre, Singapore, Department of Cardiology, 5 Hospital Drive, Singapore 169609
| | - Boon Wah Liew
- Changi General Hospital, Department of Cardiology, 2 Simei Street 3, Singapore 529889
| | - Patrick Zhan Yun Lim
- Khoo Teck Puat Hospital, Department of Cardiology, 90 Yishun Central, Singapore 768828
| | - Saurabh Rastogi
- Ng Teng Fong General Hospital, Department of Cardiology, 1 Jurong East Street 21, Singapore 609606
| | - Wei Chieh Jack Tan
- Sengkang General Hospital, Department of Cardiology, 110 Sengkang East Way, Singapore 544886
| | - Hee Hwa Ho
- Tan Tock Seng Hospital, Department of Cardiology, 11 Jalan Tan Tock Seng, Singapore 308433
| | - Khung Keong Yeo
- National Heart Centre, Singapore, Department of Cardiology, 5 Hospital Drive, Singapore 169609
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Koh SJQ, Yap J, Jiang Y, Sng GGR, Low YH, Lau YH, Sin YKK, Yeo KK. Clinical outcomes in end stage renal disease on dialysis and severe coronary artery disease: A real-world study. Int J Cardiol 2023; 378:105-110. [PMID: 36796490 DOI: 10.1016/j.ijcard.2023.02.029] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/04/2022] [Revised: 10/23/2022] [Accepted: 02/12/2023] [Indexed: 02/17/2023]
Abstract
BACKGROUND The optimal management of patients with end-stage renal disease (ESRD) on dialysis with severe coronary artery disease (CAD) has not been determined. METHODS Between 2013 and 2017, all patients with ESRD on dialysis who had left main (LM) disease, triple vessel disease (TVD) and/or severe CAD for consideration of coronary artery bypass graft (CABG) were included. Patients were divided into 3 groups based on final treatment modality: CABG, percutaneous coronary intervention (PCI), optimal medical therapy (OMT). Outcome measures include in-hospital, 180-day, 1-year and overall mortality and major adverse cardiac events (MACE). RESULTS In total, 418 patients were included (CABG 11.0%, PCI 65.6%, OMT 23.4%). Overall, 1-year mortality and MACE rates were 27.5% and 55.0% respectively. Patients who underwent CABG were significantly younger, more likely to have LM disease and have no prior heart failure. In this non-randomized setting, treatment modality did not impact on 1-year mortality, although the CABG group had significantly lower 1-year MACE rates (CABG 32.6%, PCI 57.3%, OMT 59.2%; CABG vs. OMT p < 0.01, CABG vs. PCI p < 0.001). Independent predictors of overall mortality include STEMI presentation (HR 2.31, 95% CI 1.38-3.86), prior heart failure (HR 1.84, 95% CI 1.22-2.75), LM disease (HR 1.71, 95% CI 1.26-2.31), NSTE-ACS presentation (HR 1.40, 95% CI 1.03-1.91) and increased age (HR 1.02, 95% CI 1.01-1.04). CONCLUSION Treatment decisions for patients with severe CAD with ESRD on dialysis are complex. Understanding independent predictors of mortality and MACE in specific treatment subgroups may provide valuable insights into the selection of optimal treatment options.
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Affiliation(s)
| | - Jonathan Yap
- Department of Cardiology, National Heart Centre Singapore, Singapore
| | - Yilin Jiang
- Department of Cardiology, National Heart Centre Singapore, Singapore
| | | | - Yi Hua Low
- Department of Cardiology, National Heart Centre Singapore, Singapore
| | - Yee How Lau
- Department of Cardiology, National Heart Centre Singapore, Singapore
| | - Yoong Kong Kenny Sin
- Department of Cardiothoracic Surgery, National Heart Centre Singapore, Singapore
| | - Khung Keong Yeo
- Department of Cardiology, National Heart Centre Singapore, Singapore; Duke-NUS Medical School, Singapore.
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Lau YH, Tang EWH, Lai THT, Li KKW. Acute acquired esotropia during the COVID-19 pandemic: four case reports. Hong Kong Med J 2023; 29:165-167. [PMID: 37005073 DOI: 10.12809/hkmj219856] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/04/2023] Open
Affiliation(s)
- Y H Lau
- Department of Ophthalmology, United Christian Hospital and Tseung Kwan O Hospital, Hong Kong SAR, China
- Department of Ophthalmology, School of Clinical Medicine, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong SAR, China
| | - E W H Tang
- Department of Ophthalmology, United Christian Hospital and Tseung Kwan O Hospital, Hong Kong SAR, China
- Department of Ophthalmology, School of Clinical Medicine, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong SAR, China
| | - T H T Lai
- Department of Ophthalmology, United Christian Hospital and Tseung Kwan O Hospital, Hong Kong SAR, China
- Department of Ophthalmology, School of Clinical Medicine, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong SAR, China
| | - K K W Li
- Department of Ophthalmology, United Christian Hospital and Tseung Kwan O Hospital, Hong Kong SAR, China
- Department of Ophthalmology, School of Clinical Medicine, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong SAR, China
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Lau YH, Wan LY, Lam MHC. First-line Therapy for Metastatic Castration-sensitive Prostate Cancer. Hong Kong Journal of Radiology 2022. [DOI: 10.12809/hkjr2217577] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Affiliation(s)
- YH Lau
- Department of Oncology, United Christian Hospital, Hong Kong
| | - LY Wan
- Department of Oncology, United Christian Hospital, Hong Kong
| | - MHC Lam
- Department of Oncology, United Christian Hospital, Hong Kong
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Chng BLK, Heng WMP, Soon YM, Hon JS, Lau YH, Tan RS, Tan JWC. Safety, adherence and efficacy of PCSK9 inhibitors: a retrospective real-world study. Proceedings of Singapore Healthcare 2022. [DOI: 10.1177/20101058221144115] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/04/2022] Open
Abstract
Introduction PCSK9 inhibitors demonstrated their effectiveness in reducing low-density lipoprotein cholesterol (LDL-C) and cardiovascular events in landmark trials. It remains unclear whether the results can be translated to Asian populations. This study was designed to assess the real-world safety, adherence and efficacy of PCSK9 inhibitors. Methods A retrospective review for patients newly initiated on PCSK9 inhibitors between 1st June 2017 and 31st July 2021 was conducted in a tertiary cardiology centre. Patients aged ≥ 21 years with a minimum one-month follow-up were included. Adverse drug reactions (ADRs), drug discontinuation, adherence patterns and efficacy between evolocumab and alirocumab groups were compared. Multivariable and propensity score adjusted Cox regression analyses were applied to analyse the outcomes. Results Of 87 patients screened, 80 (51 evolocumab; 29 alirocumab) were included. There were no significant differences between evolocumab and alirocumab groups in ADRs (11.8% vs 3.4%, adjusted HR, 2.97; 95% CI, 0.34 – 25.89 in multivariable analysis; adjusted HR, 3.24; 95% CI, 0.38–27.69 after propensity score adjustment) and discontinuation rates (27.5% vs 34.5%, adjusted HR, 0.89; 95% CI, 0.40–2.02 in multivariable analysis; adjusted HR, 0.88; 95% CI, 0.39–1.99 after propensity score adjustment). High medication cost was the main reason for discontinuation. One-third of patients had inadequate adherence to PCSK9 inhibitors. Both groups showed significant reductions of LDL-C compared to baseline. Conclusions PCSK9 inhibitors are efficacious, safe and well tolerated. Further studies are warranted to examine the cost-effectiveness of PCSK9 inhibitors to rationalise their sustainable use for cardiovascular prevention.
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Affiliation(s)
- Bee Ling Kelly Chng
- Department of Pharmacy, National Heart Centre Singapore, Singapore, Singapore
| | - Wei Min Paul Heng
- Department of Pharmacy, National Heart Centre Singapore, Singapore, Singapore
| | - Yu Ming Soon
- Department of Pharmacy, National Heart Centre Singapore, Singapore, Singapore
| | - Jin Shing Hon
- Department of Pharmacy, National Heart Centre Singapore, Singapore, Singapore
| | - Yee How Lau
- Singapore Cardiac Data Bank, National Heart Centre Singapore, Singapore, Singapore
| | - Ru San Tan
- Department of Cardiology, National Heart Centre Singapore, Singapore, Singapore
- Duke National University of Singapore Graduate Medical School, Singapore, Singapore
| | - Jack Wei Chieh Tan
- Department of Cardiology, National Heart Centre Singapore, Singapore, Singapore
- Duke National University of Singapore Graduate Medical School, Singapore, Singapore
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Dai L, Chakraborty S, Wu G, Ye J, Lau YH, Ramanarayan H, Wu DT. Molecular simulation of linear octacosane via a CG10 coarse grain scheme. Phys Chem Chem Phys 2022; 24:5351-5359. [PMID: 35169819 DOI: 10.1039/d1cp05143a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Following our previous work on the united-atom simulation on octacosane (C28H58) (Dai et al., Phys. Chem. Chem. Phys., 2021, 23, 21262-21271), we developed a coarse grain scheme (CG10), which is able to reproduce the pivotal phase characteristics of octacosane with highly improved computational efficiency. The CG10 octacosane chain was composed of 10 consecutive beads, maintaining the fundamental zigzag chain morphology. When the potential functions were set up and the coefficients were parameterized, our CG10 models yielded solid phase diagrams and transitions during an annealing process. We also detected the melting point by various means: direct observation, bond order, density tracking, and an enthalpy plot. Furthermore, our CG10 successfully reproduced the liquid density with only 2% underestimation, indicating its applicability across the solid and liquid phases. Therefore, with the ability to reproduce critical structure and property characteristics, our CG10 scheme provides an effective means of numerically modelling octacosane with highly improved computational efficiency.
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Affiliation(s)
- L Dai
- Institute of High Performance Computing, Agency for Science, Technology and Research (A*STAR), Singapore.
| | - S Chakraborty
- Institute of High Performance Computing, Agency for Science, Technology and Research (A*STAR), Singapore.
| | - G Wu
- Institute of High Performance Computing, Agency for Science, Technology and Research (A*STAR), Singapore.
| | - J Ye
- Institute of High Performance Computing, Agency for Science, Technology and Research (A*STAR), Singapore.
| | - Y H Lau
- Institute of High Performance Computing, Agency for Science, Technology and Research (A*STAR), Singapore.
| | - H Ramanarayan
- Institute of High Performance Computing, Agency for Science, Technology and Research (A*STAR), Singapore.
| | - D T Wu
- Institute of High Performance Computing, Agency for Science, Technology and Research (A*STAR), Singapore.
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8
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yap J, Tham MY, Poh J, Toh D, Chan CL, Lim TW, Lim SL, Chia YW, Lim YT, Choo J, Ding ZP, Foo LL, Kuo S, Lau YH, Lee A, Yeo KK. Pericarditis and myocarditis after COVID-19 mRNA vaccination in a nationwide setting. Ann Acad Med Singap 2022. [DOI: 10.47102/annals-acadmedsg.2021425] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Introduction: Despite reports suggesting an association between COVID-19 mRNA vaccination and pericarditis and myocarditis, detailed nationwide population-based data are sparsely available. We describe the incidence of pericarditis and myocarditis by age categories and sex after COVID-19 mRNA vaccination from a nationwide mass vaccination programme in Singapore.
Methods: The incidence of adjudicated cases of pericarditis and myocarditis following COVID-19 mRNA vaccination that were reported to the vaccine safety committee between January to July 2021 was compared with the background incidence of myocarditis in Singapore.
Results: As of end July 2021, a total of 34 cases were reported (9 pericarditis only, 14 myocarditis only, and 11 concomitant pericarditis and myocarditis) with 7,183,889 doses of COVID-19 mRNA vaccine administered. Of the 9 cases of pericarditis only, all were male except one. The highest incidence of pericarditis was in males aged 12–19 years with an incidence of 1.11 cases per 100,000 doses. Of the 25 cases of myocarditis, 80% (20 cases) were male and the median age was 23 years (range 12–55 years) with 16 cases after the second dose. A higher-than-expected number of cases were seen in males aged 12–19 and 20–29 years, with incidence rates of 3.72 and 0.98 case per 100,000 doses, respectively.
Conclusion: Data from the national registry in Singapore indicate an increased incidence of pericarditis and myocarditis in younger men after COVID-19 mRNA vaccination.
Keywords: COVID-19 vaccine, myocarditis, pericarditis
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Affiliation(s)
| | | | | | | | | | | | | | | | | | | | | | | | | | | | - Annie Lee
- National Heart Centre Singapore, Singapore
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Yap J, Tham MY, Poh J, Toh D, Chan CL, Lim TW, Lim SL, Chia YW, Lim YT, Choo J, Ding ZP, Foo LL, Kuo S, Lau YH, Lee A, Yeo KK. Pericarditis and myocarditis after COVID-19 mRNA vaccination in a nationwide setting. Ann Acad Med Singap 2022; 51:96-100. [PMID: 35224605] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/17/2023]
Abstract
INTRODUCTION Despite reports suggesting an association between COVID-19 mRNA vaccination and pericarditis and myocarditis, detailed nationwide population-based data are sparsely available. We describe the incidence of pericarditis and myocarditis by age categories and sex after COVID-19 mRNA vaccination from a nationwide mass vaccination programme in Singapore. METHODS The incidence of adjudicated cases of pericarditis and myocarditis following COVID-19 mRNA vaccination that were reported to the vaccine safety committee between January to July 2021 was compared with the background incidence of myocarditis in Singapore. RESULTS As of end July 2021, a total of 34 cases were reported (9 pericarditis only, 14 myocarditis only, and 11 concomitant pericarditis and myocarditis) with 7,183,889 doses of COVID-19 mRNA vaccine administered. Of the 9 cases of pericarditis only, all were male except one. The highest incidence of pericarditis was in males aged 12-19 years with an incidence of 1.11 cases per 100,000 doses. Of the 25 cases of myocarditis, 80% (20 cases) were male and the median age was 23 years (range 12-55 years) with 16 cases after the second dose. A higher-than-expected number of cases were seen in males aged 12-19 and 20-29 years, with incidence rates of 3.72 and 0.98 case per 100,000 doses, respectively. CONCLUSION Data from the national registry in Singapore indicate an increased incidence of pericarditis and myocarditis in younger men after COVID-19 mRNA vaccination.
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Affiliation(s)
- Jonathan Yap
- Department of Cardiology, National Heart Centre Singapore, Singapore
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Wong JJ, Umapathy S, Keh YS, Lau YH, Yap J, Idu M, Chin CY, Fam JM, Liew BW, Chin CT, Wong PEH, Koh TH, Yeo KK. Coronary Intravascular Lithotripsy Versus Rotational Atherectomy in an Asian Population: Clinical Outcomes in Real-World Patients. Korean Circ J 2021; 52:288-300. [PMID: 35043608 PMCID: PMC8989791 DOI: 10.4070/kcj.2021.0155] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2021] [Revised: 10/10/2021] [Accepted: 11/03/2021] [Indexed: 11/11/2022] Open
Abstract
Intravascular lithotripsy (IVL) is a newer calcium modification therapy with limited clinical experience compared to other established techniques. Single-armed studies have shown IVL is safe and effective for heavily calcified coronary lesions. This study compares our initial IVL experience with rotational atherectomy in real-world high-risk patients. We found that in-hospital adverse outcomes were not statistically significant, although 30-day major adverse cardiovascular events was higher with IVL. Differences in baseline characteristics and the small cohort numbers preclude definitive conclusions. With better experience and case selection, these outcomes are likely to improve, allowing IVL to effectively treat complex calcified coronary lesions. Background and Objectives We compared real-world clinical outcomes of patients receiving intravascular lithotripsy (IVL) versus rotational atherectomy (RA) for heavily calcified coronary lesions. Methods Fifty-three patients who received IVL from January 2017 to July 2020 were retrospectively compared to 271 patients who received RA from January 2017 to December 2018. Primary endpoints were in-hospital and 30-day major adverse cardiovascular events (MACE). Results IVL patients had a higher prevalence of acute coronary syndrome (56.6% vs 24.4, p<0.001), multivessel disease (96.2% vs 73.3%, p<0.001) and emergency procedures (17.0% vs 2.2%, p<0.001) compared to RA. In-hospital MACE (11.3% vs 5.9%, p=0.152), MI (7.5% vs 3.3%, p=0.152), and mortality (5.7% vs 3.0%, p=0.319) were not statistically significant. 30-day MACE was higher in the IVL cohort vs RA (17.0% vs 7.4%, p=0.035). Propensity score adjusted regression using IVL was also performed on in-hospital MACE (odds ratio [OR], 1.677; 95% confidence interval [CI], 0.588–4.779) and 30-day MACE (OR, 1.910; 95% CI, 0.774–4.718). Conclusions These findings represent our initial IVL experience in a high-risk, real-world cohort. Although the event rate in the IVL arm was numerically higher compared to RA, the small numbers and retrospective nature of this study preclude definitive conclusions. These clinical outcomes are likely to improve with greater experience and better case selection, allowing IVL to effectively treat complex calcified coronary lesions.
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Affiliation(s)
- Jie Jun Wong
- Department of Cardiology, National Heart Centre, Singapore
| | | | - Yann Shan Keh
- Department of Cardiology, National Heart Centre, Singapore
| | - Yee How Lau
- Department of Cardiology, National Heart Centre, Singapore
| | - Jonathan Yap
- Department of Cardiology, National Heart Centre, Singapore
| | - Muhammad Idu
- Department of Cardiology, National Heart Centre, Singapore
| | - Chee Yang Chin
- Department of Cardiology, National Heart Centre, Singapore
| | - Jiang Ming Fam
- Department of Cardiology, National Heart Centre, Singapore
| | - Boon Wah Liew
- Department of Cardiology, Changi General Hospital, Singapore
| | - Chee Tang Chin
- Department of Cardiology, National Heart Centre, Singapore
| | | | - Tian Hai Koh
- Department of Cardiology, National Heart Centre, Singapore
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Lim SL, Lau YH, Chan MY, Chua T, Tan HC, Foo D, Lim ZY, Liew BW, Shahidah N, Mao DR, Cheah SO, Chia MYC, Gan HN, Leong BSH, Ng YY, Yeo KK, Ong MEH. Early Coronary Angiography Is Associated with Improved 30-Day Outcomes among Patients with Out-of-Hospital Cardiac Arrest. J Clin Med 2021; 10:jcm10215191. [PMID: 34768711 PMCID: PMC8584598 DOI: 10.3390/jcm10215191] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2021] [Accepted: 11/04/2021] [Indexed: 11/16/2022] Open
Abstract
We evaluated the association between early coronary angiography (CAG) and outcomes in resuscitated out-of-hospital cardiac arrest (OHCA) patients, by linking data from the Singapore Pan-Asian Resuscitation Outcomes Study, with a national registry of cardiac procedures. The 30-day survival and neurological outcome were compared between patients undergoing early CAG (within 1-calender day), versus patients not undergoing early CAG. Inverse probability weighted estimates (IPWE) adjusted for non-randomized CAG. Of 976 resuscitated OHCA patients of cardiac etiology between 2011–2015 (mean(SD) age 64(13) years, 73.7% males), 337 (34.5%) underwent early CAG, of whom, 230 (68.2%) underwent PCI. Those who underwent early CAG were significantly younger (60(12) vs. 66(14) years old), healthier (42% vs. 59% with heart disease; 29% vs. 44% with diabetes), more likely males (86% vs. 67%), and presented with shockable rhythms (69% vs. 36%), compared with those who did not. Early CAG with PCI was associated with better survival and neurological outcome (adjusted odds ratio 1.91 and 1.82 respectively), findings robust to IPWE adjustment. The rates of bleeding and stroke were similar. CAG with PCI within 24 h was associated with improved clinical outcomes after OHCA, without increasing complications. Further studies are required to identify the characteristics of patients who would benefit most from this invasive strategy.
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Affiliation(s)
- Shir Lynn Lim
- Department of Cardiology, National University Heart Centre, Singapore 119228, Singapore; (M.Y.C.); (H.C.T.)
- Correspondence: ; Tel.: +65-67-723-301
| | - Yee How Lau
- Department of Cardiology, National Heart Centre, Singapore 169609, Singapore; (Y.H.L.); (T.C.); (K.K.Y.)
| | - Mark Y. Chan
- Department of Cardiology, National University Heart Centre, Singapore 119228, Singapore; (M.Y.C.); (H.C.T.)
| | - Terrance Chua
- Department of Cardiology, National Heart Centre, Singapore 169609, Singapore; (Y.H.L.); (T.C.); (K.K.Y.)
| | - Huay Cheem Tan
- Department of Cardiology, National University Heart Centre, Singapore 119228, Singapore; (M.Y.C.); (H.C.T.)
| | - David Foo
- Department of Cardiology, Tan Tock Seng Hospital, Singapore 308433, Singapore;
| | - Zhan Yun Lim
- Department of Cardiology, Khoo Teck Puat Hospital, Singapore 768828, Singapore;
| | - Boon Wah Liew
- Department of Cardiology, Changi General Hospital, Singapore 529889, Singapore;
| | - Nur Shahidah
- Department of Emergency Medicine, Singapore General Hospital, Singapore 168753, Singapore; (N.S.); (M.E.H.O.)
| | - Desmond R. Mao
- Department of Acute & Emergency Care, Khoo Teck Puat Hospital, Singapore 768828, Singapore;
| | - Si Oon Cheah
- Emergency Medicine Department, Ng Teng Fong General Hospital, Singapore 609606, Singapore;
| | - Michael Y. C. Chia
- Emergency Department, Tan Tock Seng Hospital, Singapore 308433, Singapore; (M.Y.C.C.); (Y.Y.N.)
| | - Han Nee Gan
- Accident & Emergency, Changi General Hospital, Singapore 529889, Singapore;
| | - Benjamin S. H. Leong
- Emergency Medicine Department, National University Hospital, Singapore 119074, Singapore;
| | - Yih Yng Ng
- Emergency Department, Tan Tock Seng Hospital, Singapore 308433, Singapore; (M.Y.C.C.); (Y.Y.N.)
- Ministry of Home Affairs, Singapore 329560, Singapore
| | - Khung Keong Yeo
- Department of Cardiology, National Heart Centre, Singapore 169609, Singapore; (Y.H.L.); (T.C.); (K.K.Y.)
| | - Marcus E. H. Ong
- Department of Emergency Medicine, Singapore General Hospital, Singapore 168753, Singapore; (N.S.); (M.E.H.O.)
- Health Services and Systems Research, Duke-NUS Medical School, Singapore 169857, Singapore
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12
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Wong CJ, Yap J, Gao F, Lau YH, Huang W, Yeo KK. Clinical characteristics and outcomes of myocardial infarction with nonobstructive coronary arteries. Eur Heart J 2021. [DOI: 10.1093/eurheartj/ehab724.1492] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Abstract
Background
Myocardial infarction with nonobstructive coronary arteries (MINOCA) is caused by a heterogenous group of conditions with clinically significant sequelae.
Purpose
This study aims to compare the clinical characteristics and prognosis of MINOCA with myocardial infarction with obstructive coronary artery disease (MICAD).
Methods
Data was obtained from the Singapore Cardiac Longitudinal Outcomes Database (SingCLOUD), a national multicenter registry of patients with cardiovascular disease. Patients with a first presentation of acute myocardial infarction who underwent coronary angiography between 1 January 2011 and 31 December 2014 were extracted from the database. Follow up was conducted until 31 December 2017. Subjects were classified as having either MICAD or MINOCA based on angiographic findings. The primary outcomes were all-cause mortality and major adverse cardiac events (MACE) defined as a composite of all-cause mortality, recurrent myocardial infarction, hospitalization for heart failure and ischemic stroke.
Results
All 4124 patients who met the inclusion criteria were included in this study, of which 159 (3.9%) were diagnosed with MINOCA. Patients with MINOCA were more likely to be female, present with a non-ST elevation myocardial infarction (NSTEMI), have a higher left ventricular ejection fraction and less likely to have diabetes mellitus, previous ischemic stroke or smoking history. Over a mean follow-up duration of 4.5 years, MINOCA patients had a lower incidence of all-cause mortality (10.1% vs. 16.5%, p=0.030) and MACE (20.8% vs. 35.5%, p<0.0001) compared to patients with MICAD. On multivariable analysis, patients with MINOCA had a significantly lower risk of all-cause mortality (HR 0.42; 95% CI 0.21–0.82; p=0.011), MACE (HR 0.42; 95% CI 0.26–0.69; p=0.001) and recurrent myocardial infarction (HR 0.35; 95% CI 0.15–0.85; p=0.021). Within the MINOCA group, older age, higher creatinine, a STEMI presentation and the absence of antiplatelet use predicted all-cause mortality and MACE.
Conclusions
While patients with MINOCA had better clinical outcomes compared to MICAD patients, MINOCA is not a benign entity with about one in five patients experiencing a major adverse cardiovascular event in the mid-term.
Funding Acknowledgement
Type of funding sources: Public grant(s) – National budget only. Main funding source(s): National Medical Research Council Project Grant
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Affiliation(s)
- C J Wong
- National Heart Centre Singapore, Singapore, Singapore
| | - J Yap
- National Heart Centre Singapore, Singapore, Singapore
| | - F Gao
- National Heart Centre Singapore, Singapore, Singapore
| | - Y H Lau
- National Heart Centre Singapore, Singapore, Singapore
| | - W Huang
- National Heart Centre Singapore, Singapore, Singapore
| | - K K Yeo
- National Heart Centre Singapore, Singapore, Singapore
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Dai L, Rutkevych PP, Chakraborty S, Wu G, Ye J, Lau YH, Ramanarayan H, Wu DT. Molecular dynamics simulation of octacosane for phase diagrams and properties via the united-atom scheme. Phys Chem Chem Phys 2021; 23:21262-21271. [PMID: 34543374 DOI: 10.1039/d1cp02720d] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
We used the united-atom scheme to build three types of crystalline structures for octacosane (C28H58) and carried out molecular dynamics simulations to investigate their phase properties. By gradually heating the three polymorphs, we managed to reproduce the sequence of experimentally reported crystalline phases and rotator phases. By studying the system density, molecule morphology, chain tilt angle and cell anisotropy, we hypothesized three mechanisms behind the observed system deformations and phase transformations during the annealing process. Furthermore, our model successfully predicted the melting temperature and heat of fusion. We also reproduced the characteristics of the rotator phases and the liquid phase, validating the transferability of the united-atom scheme among the different condensed phases of octacosane. Our methodology represents an effective and efficient means of numerical study for octacosane and may be used for other members of the n-alkane family.
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Affiliation(s)
- L Dai
- Institute of High Performance Computing, Agency for Science, Technology and Research (A*STAR), Singapore.
| | - P P Rutkevych
- Institute of Chemical and Engineering Sciences, Agency for Science, Technology and Research (A*STAR), Singapore
| | - S Chakraborty
- Institute of High Performance Computing, Agency for Science, Technology and Research (A*STAR), Singapore.
| | - G Wu
- Institute of High Performance Computing, Agency for Science, Technology and Research (A*STAR), Singapore.
| | - J Ye
- Institute of High Performance Computing, Agency for Science, Technology and Research (A*STAR), Singapore.
| | - Y H Lau
- Institute of High Performance Computing, Agency for Science, Technology and Research (A*STAR), Singapore.
| | - H Ramanarayan
- Institute of High Performance Computing, Agency for Science, Technology and Research (A*STAR), Singapore.
| | - D T Wu
- Institute of High Performance Computing, Agency for Science, Technology and Research (A*STAR), Singapore.
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14
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Fam JM, Khoo CY, Lau YH, Lye WK, Cai XJ, Choong LHL, Allen JC, Yeo KK. Age and diabetes mellitus associated with worse outcomes after percutaneous coronary intervention in a multi-ethnic Asian dialysis patient population. Singapore Med J 2020; 62:300-304. [PMID: 32179924 DOI: 10.11622/smedj.2020025] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
INTRODUCTION There is limited literature on clinical outcomes following percutaneous coronary intervention (PCI) in Asian dialysis patients. We evaluated the angiographic characteristics and clinical outcomes of dialysis patients treated with PCI in an Asian society. METHODS A retrospective analysis was performed of 274 dialysis patients who underwent PCI in a tertiary care institution from January 2007 to December 2012. Data on clinical and angiographic characteristics was collected. The primary endpoint was major adverse cardiac events (MACE), defined as a composite of cardiac death, acute myocardial infarction (AMI) and stroke at two years. RESULTS 274 patients (65.0% male, median age 62.0 years) with 336 lesions (81.8% Type B2) were treated. 431 stents (35.0% drug-eluting stents) with a mean diameter of 2.96 mm and mean length of 21.30 mm were implanted. The MACE rate was 55.8% (n = 153) at two years, from death (36.5%) and AMI (35.0%). In multivariable analysis, age and diabetes mellitus were significant predictors of both mortality (odds ratio [OR] 1.09, 95% confidence interval [CI] 1.05-1.12, p < 0.001; OR 2.65, 95% CI 1.46-4.82, p = 0.001, respectively) and MACE (OR 1.06, 95% CI 1.03-1.08, p < 0.001; OR 1.84, 95% CI 1.07-3.15, p = 0.027, respectively). Left ventricular ejection fraction (LVEF) (OR 0.97, 95% CI 0.95-0.99, p = 0.006) was a significant predictor of mortality but not MACE. CONCLUSION Asian dialysis patients who underwent PCI had a two-year MACE rate of 55.8% due to death and AMI. Age, LVEF and diabetes mellitus were significant predictors of mortality at two years.
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Affiliation(s)
- Jiang Ming Fam
- Department of Cardiology, National Heart Centre Singapore, Singapore
| | - Chun Yuan Khoo
- Department of Cardiology, National Heart Centre Singapore, Singapore
| | - Yee How Lau
- Department of Cardiology, National Heart Centre Singapore, Singapore
| | | | - Xinzhe James Cai
- Department of Cardiology, National Heart Centre Singapore, Singapore
| | | | | | - Khung Keong Yeo
- Department of Cardiology, National Heart Centre Singapore, Singapore
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15
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Yeo KK, Ong HY, Chua T, Lim ZJ, Yap J, Ho HH, Jaufeerally F, Tong KL, Kojodjojo P, Wong HB, Heng D, Tan KB, Richards AM, Teoh KLK, Sin K, Tan NC, Lee SBM, Lim T, Ta A, Liok E, Lau YH, Gao F, Liman C, Sarkar J, Sahlén A, Koh TH, Chan MY. Building a Longitudinal National Integrated Cardiovascular Database - Lessons Learnt From SingCLOUD. Circ Rep 2019; 2:33-43. [PMID: 33693172 PMCID: PMC7929705 DOI: 10.1253/circrep.cr-19-0106] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Background:
Real world data on clinical outcomes and quality of care for patients with coronary artery disease (CAD) are fragmented. We describe the rationale and design of the Singapore Cardiovascular Longitudinal Outcomes Database (SingCLOUD). Methods and Results:
We designed a health data grid to integrate clinical, administrative, laboratory, procedural, prescription and financial data from all public-funded hospitals and primary care clinics, which provide 80% of health care in Singapore. Here, we explain our approach to harmonize real-world data from diverse electronic medical and non-medical platforms to develop a robust and longitudinal dataset. We present pilot data on patients with myocardial infarction (MI) treated with percutaneous coronary intervention (PCI) between 2012 and 2014. The initial data set had 53,395 patients. Of these, 35,203 had CAD confirmed on coronary angiography, of whom 21,521 had PCI. Eventually, limiting to 2012–2014, 3,819 patients had MI with PCI, while 5,989 had MI. Compared with the quality improvement registry, Singapore Cardiac Data Bank, which had 189 fields for analysis, the SingCLOUD platform generated an additional 313 additional data fields, and was able to identify an additional 250 heart failure events, 664 major adverse cardiovascular events at 2 years, and low-density lipoprotein levels to 1 year for 3,747 patients. Conclusions:
By integrating multiple incongruent data sources, SINGCLOUD enables in-depth analysis of real-world cardiovascular “big data”.
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Affiliation(s)
- Khung Keong Yeo
- Department of Cardiology, National Heart Centre Singapore Singapore.,Duke-NUS Medical School Singapore
| | - Hean-Yee Ong
- Department of Cardiology, Khoo Teck Puat Hospital Singapore
| | - Terrance Chua
- Department of Cardiology, National Heart Centre Singapore Singapore.,Duke-NUS Medical School Singapore
| | - Zheng Jie Lim
- Faculty of Medicine, Nursing and Health Sciences, Monash University, Melbourne Victoria Australia
| | - Jonathan Yap
- Department of Cardiology, National Heart Centre Singapore Singapore
| | - Hee Hwa Ho
- Department of Cardiology, Tan Tock Seng Hospital Singapore
| | - Fazlur Jaufeerally
- Duke-NUS Medical School Singapore.,Department of Internal Medicine, Singapore General Hospital Singapore
| | - Khim-Leng Tong
- Department of Cardiology, Changi General Hospital Singapore
| | - Pipin Kojodjojo
- Division of Cardiology, Department of Medicine, Jurong Health Singapore
| | - Hwee-Bee Wong
- Biostatistics and Research Branch, Ministry of Health Singapore
| | - Derrick Heng
- Public Health Group, Ministry of Health Singapore
| | - Kelvin Bryan Tan
- Policy Research and Evaluation Division, Ministry of Health Singapore
| | - Arthur Mark Richards
- Cardiovascular Research Institute [CVRI], National University Heart Centre [NUHCS], National University Health System Singapore
| | | | - Kenny Sin
- Department of Cardiothoracic Surgery, National Heart Centre Singapore Singapore
| | | | | | - Terence Lim
- Integrated Health Informatics System, Ministry of Health Holdings Singapore
| | - Andy Ta
- Integrated Health Informatics System, Ministry of Health Holdings Singapore
| | - Edwin Liok
- Infocomm Media Development Authority of Singapore Singapore
| | - Yee How Lau
- Singapore Cardiac Data Bank, National Heart Centre Singapore Singapore
| | - Fei Gao
- NHRIS, National Heart Centre Singapore Singapore
| | | | | | - Anders Sahlén
- Department of Cardiology, National Heart Centre Singapore Singapore.,Karolinska Institute Stockholm Sweden
| | - Tian Hai Koh
- Department of Cardiology, National Heart Centre Singapore Singapore
| | - Mark Y Chan
- Cardiac Department, National University Hospital Singapore
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16
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Kosiborod M, Lam CS, Kohsaka S, Kim DJ, Karasik A, Shaw J, Tangri N, Goh SY, Thuresson M, Chen H, Surmont F, Hammar N, Fenici P, Kosiborod M, Cavender MA, Fu AZ, Wilding JP, Khunti K, Norhammar A, Birkeland K, Jørgensen ME, Holl RW, Lam CSP, Gulseth HL, Carstensen B, Bollow E, Franch-Nadal J, García Rodríguez LA, Karasik A, Tangri N, Kohsaka S, Kim DJ, Shaw J, Arnold S, Goh SY, Hammar N, Fenici P, Bodegård J, Chen H, Surmont F, Nahrebne K, Blak BT, Wittbrodt ET, Saathoff M, Noguchi Y, Tan D, Williams M, Lee HW, Greenbloom M, Kaidanovich-Beilin O, Yeo KK, Bee YM, Khoo J, Koong A, Lau YH, Gao F, Tan WB, Kadir HA, Ha KH, Lee J, Chodick G, Melzer Cohen C, Whitlock R, Cea Soriano L, Fernándex Cantero O, Riehle E, Ilomaki J, Magliano D. Cardiovascular Events Associated With SGLT-2 Inhibitors Versus Other Glucose-Lowering Drugs. J Am Coll Cardiol 2018. [DOI: 10.1016/j.jacc.2018.03.009] [Citation(s) in RCA: 238] [Impact Index Per Article: 39.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
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Abstract
With increasing emphasis on patient autonomy, patients are encouraged to be more involved in end-of-life issues, including the use of extraordinary efforts to prolong their lives. Being able to make anticipatory decisions is seen to promote autonomy, empower patients and optimise patient care. To facilitate shared decision-making, patients need to have a clear and accurate understanding of cardiopulmonary resuscitation (CPR). This study aims to understand the knowledge and perspectives of the local community regarding resuscitation options and end-of-life decision-making and to explore ways to improve the quality of end-of-life discussions. An interviewer-administered survey was conducted with a prospectively recruited group of surgical patients admitted postoperatively to the day surgery ward of a single tertiary institution in Singapore from April to May 2015. The survey, modelled after two validated questionnaires, measured patients' knowledge, attitudes and preferences regarding CPR in a series of 18 questions. Fifty-one out of 67 (76.1%) patients completed the survey. Results indicated that 80.4% (n=41) of participants correctly understood the purpose of CPR, but 64.7% (n=33) did not know of any possible complications of CPR. Less than half (n=21, 41.2%) of participants had thought about life support measures they wanted for themselves. Most of the participants agreed that they should personally be involved in making end-of-life decisions (n=44, 86.3%). Many patients had a poor knowledge of CPR and other resuscitation measures and the majority overestimated the success rate of CPR. However, a majority were receptive to improving their knowledge and keen to discuss end-of-life issues with physicians.
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Affiliation(s)
- S Wee
- Resident, Department of Anaesthesiology, Intensive Care and Pain Medicine, Tan Tock Seng Hospital, Singapore
| | - Z Y Chang
- Medical student, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
| | - Y H Lau
- Consultant, Department of Anaesthesiology, Intensive Care and Pain Medicine, Tan Tock Seng Hospital, Singapore
| | - Yky Wong
- Senior Epidemiologist, Clinical Research and Innovation Office, Tan Tock Seng Hospital, Singapore
| | - Cym Ong
- Consultant, Department of Anaesthesiology, Intensive Care and Pain Medicine, Tan Tock Seng Hospital, Singapore
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18
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Sahlén A, Hamid N, Amanullah MR, Fam JM, Yeo KK, Lau YH, Lam CSP, Ding ZP. Impact of aortic root size on left ventricular afterload and stroke volume. Eur J Appl Physiol 2016; 116:1355-65. [PMID: 27179797 DOI: 10.1007/s00421-016-3392-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2016] [Accepted: 05/09/2016] [Indexed: 10/21/2022]
Abstract
PURPOSE The left ventricle (LV) ejects blood into the proximal aorta. Age and hypertension are associated with stiffening and dilation of the aortic root, typically viewed as indicative of adverse remodeling. Based on analytical considerations, we hypothesized that a larger aortic root should be associated with lower global afterload (effective arterial elastance, EA) and larger stroke volume (SV). Moreover, as antihypertensive drugs differ in their effect on central blood pressure, we examined the role of antihypertensive drugs for the relation between aortic root size and afterload. METHODS We studied a large group of patients (n = 1250; 61 ± 12 years; 78 % males; 64 % hypertensives) from a single-center registry with known or suspected coronary artery disease. Aortic root size was measured by echocardiography as the diameter of the tubular portion of the ascending aorta. LV outflow tract Doppler was used to record SV. RESULTS In the population as a whole, after adjusting for key covariates in separate regression models, aortic root size was an independent determinant of both SV and EA. This association was found to be heterogeneous and stronger in patients taking a calcium channel blocker (CCB; 10.6 % of entire population; aortic root size accounted for 8 % of the explained variance of EA). CONCLUSION Larger aortic root size is an independent determinant of EA and SV. This association was heterogeneous and stronger in patients on CCB therapy.
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Affiliation(s)
- Anders Sahlén
- National Heart Centre Singapore, 5 Hospital Drive, Singapore, 169609, Singapore. .,Karolinska Institutet, Department of Cardiology, Karolinska University Hospital, 141 86, Stockholm, Sweden.
| | - Nadira Hamid
- National Heart Centre Singapore, 5 Hospital Drive, Singapore, 169609, Singapore
| | | | - Jiang Ming Fam
- National Heart Centre Singapore, 5 Hospital Drive, Singapore, 169609, Singapore
| | - Khung Keong Yeo
- National Heart Centre Singapore, 5 Hospital Drive, Singapore, 169609, Singapore
| | - Yee How Lau
- National Heart Centre Singapore, 5 Hospital Drive, Singapore, 169609, Singapore
| | - Carolyn S P Lam
- National Heart Centre Singapore, 5 Hospital Drive, Singapore, 169609, Singapore
| | - Zee Pin Ding
- National Heart Centre Singapore, 5 Hospital Drive, Singapore, 169609, Singapore
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19
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Zhong L, Lau YH, Sim LL, Sim D, Kwok B, Chua T, Lee R, Tan RS. CONCENTRIC LEFT VENTRICULAR HYPERTROPHY AS INDEPENDENT PREDICTOR OF 1-YEAR REHOSPITALIZATION AND MORTALITY IN PATIENTS HOSPITALIZED FOR ACUTE HEART FAILURE AND PRESERVED EJECTION FRACTION. J Am Coll Cardiol 2012. [DOI: 10.1016/s0735-1097(12)60855-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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20
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Ang CY, Sim LL, Gao F, Lau YH, Lim ST, Chua TSJ, Khurana R. AS-033 Validation of British Columbia-Percutaneous Coronary Intervention (BC PCI) Risk Score Using the Singapore Cardiac Data Bank. Am J Cardiol 2011. [DOI: 10.1016/j.amjcard.2011.02.058] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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21
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Heng KWJ, Tham KY, How KY, Foo JS, Lau YH, Li AYK. Recall of discharge advice given to patients with minor head injury presenting to a Singapore emergency department. Singapore Med J 2007; 48:1107-1110. [PMID: 18043837] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
INTRODUCTION Most patients presenting to the emergency department (ED) with minor head injury (HI) can be discharged, provided a caregiver is present and careful discharge instructions are given. The study ED uses an advice leaflet with verbal reinforcement to patients and caregivers detailing post-discharge instructions and warning symptoms of worsening HI. We aim to evaluate local patients' and caregivers' compliance to discharge instructions and their ability to recall HI advice. METHODS A prospective study was conducted in an adult ED between April 10, 2006 and May 1, 2006. All patients with minor HI discharged from the ED or its 24-hour observation ward were included in the study. A telephone survey was conducted within 48 hours of discharge using a standardised questionnaire. RESULTS During the study period, 292 patients had HI, of which 182 were eligible for the study. 71 were uncontactable and one refused to participate, leaving 110 patients in the study. Patients' age ranged between 7 and 109 years (median 41 years). 100 confirmed receiving HI advice (57 percent received by patients, 26 percent caregivers, 16 percent both patients and caregivers). 29 percent of respondents reported non-compliance to discharge advice. Mean HI-symptom recall score was 1.9 (SD 1.6) (total 9 symptoms). 30 percent cited other symptoms not part of the HI advice, which they believed necessitated a return to the ED. Recall scores were not statistically different, regardless of mode of instruction (verbal or printed) or the recipient (patient, caregiver or both). CONCLUSION Our study raises concerns about the reliability of discharge advice for minor HI patients.
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Affiliation(s)
- K W J Heng
- Emergency Department, Tan Tock Seng Hospital, 11 Jalan Tan Tock Seng, Singapore 308433.
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22
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Lau YH, Braun M, Hutton BF. Non-rigid image registration using a median-filtered coarse-to-fine displacement field and a symmetric correlation ratio. Phys Med Biol 2001; 46:1297-319. [PMID: 11324966 DOI: 10.1088/0031-9155/46/4/326] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Conventional approaches to image registration are generally limited to image-wide rigid transformations. However, the body and its internal organs are non-rigid structures that change shape due to changes in the body's posture during image acquisition, and due to normal, pathological and treatment-related variations. Inter-subject matching also constitutes a non-rigid registration problem. In this paper, we present a fully automated non-rigid image registration method that maximizes a local voxel-based similarity metric. Overlapping image blocks are defined on a 3D grid. The transformation vector field representing image deformation is found by translating each block so as to maximize the local similarity measure. The resulting sparsely sampled vector field is median filtered and interpolated by a Gaussian function to ensure a locally smooth transformation. A hierarchical strategy is adopted to progressively establish local registration associated with image structures at diminishing scale. Simulation studies were carried out to evaluate the proposed algorithm and to determine the robustness of various voxel-based cost functions. Mutual information, normalized mutual information, correlation ratio (CR) and a new symmetric version of CR were evaluated and compared. A T1-weighted magnetic resonance (MR) image was used to test intra-modality registration. Proton density and T2-weighted MR images of the same subject were used to evaluate inter-modality registration. The proposed algorithm was tested on the 2D MR images distorted by known deformations and 3D images simulating inter-subject distortions. We studied the robustness of cost functions with respect to image sampling. Results indicate that the symmetric CR gives comparable registration to mutual information in intra- and inter-modality tasks at full sampling and is superior to mutual information in registering sparsely sampled images.
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Affiliation(s)
- Y H Lau
- Department of Applied Physics, University of Technology, Sydney, NSW, Australia
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23
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Lau YH, Hutton BF, Beekman FJ. Choice of collimator for cardiac SPET when resolution compensation is included in iterative reconstruction. Eur J Nucl Med 2001; 28:39-47. [PMID: 11202450 DOI: 10.1007/s002590000387] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
In clinical cardiac single-photon emission tomography (SPET) studies, collimators of different spatial resolution and geometric efficiency are available for imaging. In selecting the appropriate collimator for clinical use, there is a trade-off between spatial resolution, which can limit the contrast of the reconstructed image, and detection efficiency, which determines the noise in the image. Our objective was to assess which collimator is best suited for cardiac SPET when reconstruction is performed with and without compensation for distance-dependent resolution (CDR). The dynamic MCAT thorax phantom was used to simulate 180 degree technetium-99m cardiac data, acquired using either a general-purpose (GP) or high-resolution (HR) collimator. For GP and HR, the resolution at 15 cm was 11.5 mm and 9.5 mm respectively, and the corresponding relative efficiency was 1.0 and 0.52 respectively. Distance-dependent resolution, attenuation and noise were included in the projection data; scatter was not included. Ordered subsets expectation maximisation reconstruction (subset size 4) was performed with and without CDR. Results were evaluated by comparing the myocardial recovery coefficient and contrast between myocardium and ventricle relative to the original phantom, each plotted for different noise levels corresponding to increasing iteration number. The study demonstrated that, without CDR, HR gave the best results. However, for any given noise level with CDR, GP gave superior recovery and contrast. These findings were confirmed in a physical phantom study. Results suggest that improved reconstruction can be achieved using a GP collimator in combination with resolution compensation.
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Affiliation(s)
- Y H Lau
- Department of Medical Physics, Westmead Hospital, Sydney, NSW, Australia
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24
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Abstract
Mutual information has been proposed as a criterion for image registration. The criterion is calculated from a two-dimensional grey-scale histogram of the image pair being registered. In this paper we study how sparse sampling can be used to increase speed performance using the registration algorithm of Maes et al. (IEEE Trans Med Imaging 1997; 16: 187-198) with a focus on registration of MRI-SPET brain images. In particular we investigate how sparse sampling and parameters such as the number of bins used for the grey-scale histograms and smoothing of the data prior to registration affect accuracy and robustness of the registration. The method was validated using both simulated and human data. Our results show that sparse sampling introduced local maxima into the mutual information similarity function when the number of bins used for the histograms was large. To speed up registration while retaining robustness, smoothing of the data prior to registration was used and a coarse to fine subsampling protocol, where the number of bins in the histograms were dependent on the subsampling factor, was employed, For the simulated data, the method was able to recover known transformations with an accuracy of about 1 mm. Using the human data, there were no significant differences in the recovered transformation parameters when the suggested subsampling scheme was used compared with when no subsampling was used, but there was a more than tenfold increase in speed. Our results show that, with the appropriate choice of parameters, the method can accurately register MRI-SPET brain images even when very efficient sampling protocols are used.
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Affiliation(s)
- L Thurfjell
- Centre for Image Analysis, Uppsala University, Sweden
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25
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Abstract
Compensation for distance-dependent resolution can be directly incorporated in maximum likelihood reconstruction. Our objective was to examine the effectiveness of this compensation using either the standard expectation maximization (EM) algorithm or an accelerated algorithm based on use of ordered subsets (OSEM). We also investigated the application of post-reconstruction filtering in combination with resolution compensation. Using the MCAT phantom, projections were simulated for 360 degrees data, including attenuation and distance-dependent resolution. Projection data were reconstructed using conventional EM and OSEM with subset size 2 and 4, with/without 3D compensation for detector response (CDR). Also post-reconstruction filtering (PRF) was performed using a 3D Butterworth filter of order 5 with various cutoff frequencies (0.2-1.2 cycles cm(-1)). Image quality and reconstruction accuracy were improved when CDR was included. Image noise was lower with CDR for a given iteration number. PRF with cutoff frequency greater than 0.6 cycles cm(-1) improved noise with no reduction in recovery coefficient for myocardium but the effect was less when CDR was incorporated in the reconstruction. CDR alone provided better results than use of PRF without CDR. Results suggest that using CDR without PRF, and stopping at a small number of iterations, may provide sufficiently good results for myocardial SPECT. Similar behaviour was demonstrated for OSEM.
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Affiliation(s)
- B F Hutton
- Department of Medical Physics, Westmead Hospital, Sydney, Westmead NSW, Australia.
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Susskind H, Weber DA, Lau YH, Park TL, Atkins HL, Franceschi D, Meek AG, Ivanovic M, Wielopolski L. Impaired permeability in radiation-induced lung injury detected by technetium-99m-DTPA lung clearance. J Nucl Med 1997; 38:966-71. [PMID: 9189152] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
UNLABELLED This study evaluates the use of the 99mTc-DTPA aerosol lung clearance method to investigate radiation-induced lung changes in eight patients undergoing radiotherapy for lung or breast carcinoma. The sensitivity of the method was compared with chest radiography for detecting radiation-induced changes in the lung, regional alterations within (irradiated region) and outside (shielded region) the treatment ports, effect of irradiated lung volume, and dependence on time after radiotherapy. METHODS Serial DTPA lung clearance studies were performed before the first radiation treatment (baseline), then weekly during a 5- to 7-wk course, and up to 12 times post-therapy over periods of 56-574 days. The total activity deposited in the lungs for each study was approximately 150 microCi (approximately 5.6 MBq). DTPA clearance, expressed in terms of the biological half-time, t 1/2, was computed from the slopes of the least-squares fit regression lines of the time-activity curves for the first 10 min for irradiated and shielded lung regions. RESULTS Major findings include: (a) significant and early DTPA t 1/2 changes were observed in all patients during and after radiotherapy; (b) changes in DTPA t 1/2 values were observed in both irradiated and shielded lung regions in all patients suggesting a radiation-induced systemic reaction; (c) changes in DTPA t 1/2 values were correlated (p < 0.05) with the irradiated lung volumes; (d) significantly reduced DTPA t 1/2 values were observed in three patients who subsequently presented with clinical symptoms and/or radiographic changes consistent with radiation pneumonitis (t1/2 felt to 19% +/- 6% of baseline values, compared with 64% +/- 17% in the remaining patients [p < 0.01]); (e) the onset of decreased DTPA t 1/2 values in these three patients occurred 35-84 days before clinical symptoms and/or radiographic changes; and (f) DTPA t 1/2 tended to approach baseline values with time after radiotherapy, suggesting a long-term recovery in lung injury. CONCLUSION These observations show significant and early alterations in DTPA lung clearance during and after radiotherapy that may provide a sensitive assay to monitor changes in radiation-induced lung injury and may facilitate early therapeutic intervention.
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Affiliation(s)
- H Susskind
- Clinical Research Center, Brookhaven National Laboratory, Upton, New York 11973-5000, USA
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Wang GJ, Volkow ND, Lau YH, Fowler JS, Meek AG, Park TL, Wong C, Roque CT, Adler AJ, Wolf AP. Glucose metabolic changes in nontumoral brain tissue of patients with brain tumor following radiotherapy: a preliminary study. J Comput Assist Tomogr 1996; 20:709-14. [PMID: 8797898 DOI: 10.1097/00004728-199609000-00004] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
PURPOSE Our goal was to measure the effect of radiotherapy on the brain glucose metabolism of tumoral and nontumoral tissue of patients with brain malignancies. METHOD Fifteen patients with primary or metastatic brain tumors were studied with 2-deoxy-2-[18F]fluoro-D-glucose and PET prior to radiotherapy, and nine of them were rescanned 1 week after completing radiotherapy. RESULTS Brain metabolism in patients (all brain regions except for tumoral and edematous tissue) was lower than that of matched controls (34.0 +/- 8.3 vs. 46.5 +/- 6.4 mumol/100 g/min; p < or = 0.0001). Five of the nine patients retested after radiotherapy showed decrements in tumor metabolism (47 +/- 10%; p < or = 0.05) and increases in brain metabolism (10 +/- 4%; p < or = 0.004), and the other four showed no changes in tumor or in brain metabolism. Radiotherapy-induced changes in tumor metabolism were negatively correlated with changes in brain metabolism (r = 0.85, p < or = 0.004), but not with changes in tumor volume (assessed with MR images). CONCLUSION The study indicates that radiotherapy-induced increases in metabolism of nontumoral tissue are secondary to decreased tumor metabolic activity and not just due to volume reduction.
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Affiliation(s)
- G J Wang
- Medical Department, Brookhaven National Laboratory, Upton, NY 11973, USA
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Affiliation(s)
- Y H Lau
- Department of Dentistry, Taichung Veterans General Hospital, Taiwan, Republic of China
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Abstract
Ca2+ transport by sarcoplasmic reticulum vesicles was examined by incubating sarcoplasmic reticulum vesicles (0.15 mg/ml) at 37 degrees C in, either normal medium that contained 0.15 M sucrose, 0.1 M KCl, 60 microM CaCl2, 2.5 mM ATP and 30 mM Tes at pH 6.8, or a modified medium for elimination of ADP formed from ATP hydrolysis by including, in addition, 3.6 mM phosphocreatine and 33 U/ml of creatine phosphokinase. In normal medium, Ca2+ uptake of sarcoplasmic reticulum vesicles reached a plateau of about 100 nmol/mg. In modified medium, after this phase of Ca2+ uptake, a second phase of Ca2+ accumulation was initiated and reached a plateau of about 300 nmol/mg. The second phase of Ca2+ accumulation was accompanied by phosphate uptake and could be inhibited by ADP. Since, under these experimental conditions, there was no significant difference of the rates of ATP hydrolysis in normal medium and modified medium, extra Ca2+ uptake in modified medium but not in normal medium could not be explained by different phosphate accumulation in the two media. Unidirectional Ca2+ influx of sarcoplasmic reticulum near steady state of Ca2+ uptake was measured by pulse labeling with 45Ca2+. The Ca2+ efflux rate was then determined by subtracting the net uptake from the influx rate. At the first plateau of Ca2+ uptake in normal medium, Ca2+ influx was balanced by Ca2+ efflux with an exchange rate of 240 nmol/mg per min. This exchange rate was maintained relatively constant at the plateau phase. In modified medium, the Ca2+ exchange rate at the first plateau of Ca2+ uptake was about half of that in normal medium. When the second phase of Ca2+ uptake was initiated, both the influx and efflux rates started to increase and reached a similar exchange rate as observed in normal medium. Also, during the second phase of Ca2+ uptake, the difference between the influx and efflux rates continued to increase until the second plateau phase was approached. In conditions where the formation of ADP and inorganic phosphate was minimized by using a low concentration of sarcoplasmic (7.5 micrograms/ml) and/or using acetyl phosphate instead of ATP, the second phase of Ca2+ uptake was also observed. These data suggest that the Ca2+ load attained by sarcoplasmic reticulum vesicles during active transport is modulated by ADP accumulated from ATP hydrolysis. ADP probably exerts its effect by facilitating Ca2+ efflux, which subsequently stimulates Ca2+ exchange.
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Lau YH, Caswell AH, Garcia M, Letellier L. Ouabain binding and coupled sodium, potassium, and chloride transport in isolated transverse tubules of skeletal muscle. J Gen Physiol 1979; 74:335-49. [PMID: 479825 PMCID: PMC2228522 DOI: 10.1085/jgp.74.3.335] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
The affinity and number of binding sites of [3H]ouabain to isolated transverse (T) tubules were determined in the absence and presence of deoxycholate. In both conditions the KD was approximately 53 nM while deoxycholate increased the number of binding sites from 3.5 to 37 pmol/mg protein. We concluded that the ouabain binding sites were located primarily on the inside of the isolated vesicle and that the vesicles were impermeable to ouabain. ATP induced a highly active Na+ accumulation by the T tubules which increased Na+ in the T tubular lumen by almost 200 nmol/mg protein. The accumulation had an initial fast phase lasting 2-3 min and a subsequent slow phase which continued for at least 40 min. The rate of the initial fast phase indicated a turnover number of 20 Na+/s. The Na+ accumulation was prevented by monensin but was unaffected by valinomycin. Ouabain did not influence Na+ uptake, but digitoxin inhibited it. At low K+ the accumulation of Na+ was reduced 3.7-fold below the value at 50 mM K+. 86Rb, employed as a tracer to detect K+, showed a first phase of K+ release while Na+ was accumulated. After 2-3 min, K+ was reaccumulated while Na+ continued to increase in the lumen. T tubules accumulated Cl- on addition of ATP. This suggested that ATP initiated an exchange of Na+ for K+ followed by uptake of Na+ and K+ accompanied by Cl-.
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Weld FM, Bigger JT, Swistel D, Bordiuk J, Lau YH. Electrophysiological effects of mexiletine (Kö1173) on ovine cardiac Purkinje fibers. J Pharmacol Exp Ther 1979; 210:222-8. [PMID: 458628] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
To clarify the electrophysiological mechanisms of the antiarrhythmic effects of mexiletine, we examined the actions of mexiletine (0.1--30 mg/l) on action potential characteristics (phase 0 amplitude, overshoot, maximum upstroke velocity, maximum diastolic and activation voltages, duration at 50% and 90% repolarization) of cardiac Purkinje fibers using standard microelectrode techniques. In fibers stimulated at constant rate, mexiletine decreased phase 0 amplitude and Vmax and shortened the action potential. Mexiletine shortened action potential duration at lower concentrations than those which altered phase 0 depolarization. The effect of mexiletine on normal automaticity in cardiac Purkinje fibers was studied in fibers made automatic either by hypokalemia or by isoproterenol. Mexiletine suppressed normal automaticity by shifting activation voltage, so that spontaneous phase 4 depolarization reached a stable resting voltage without triggering regenerative phase 0 depolarization. The effects of mexiletine on abnormal automaticity were studied in Purkinje fibers intoxicated by ouabain. Mexiletine decreased the amplitude of or abolished either early or delayed after depolarizations induced by ouabain.
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Lau YH, Caswell AH, Brunschwig JP, Baerwald RJ, Garcia M. Lipid analysis and freeze-fracture studies on isolated transverse tubules and sarcoplasmic reticulum subfractions of skeletal muscle. J Biol Chem 1979; 254:540-6. [PMID: 762077] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
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Caswell AH, Lau YH, Garcia M, Brunschwig JP. Recognition and junction formation by isolated transverse tubules and terminal cisternae of skeletal muscle. J Biol Chem 1979; 254:202-8. [PMID: 758320] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
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Lau YH, Caswell AH, Brunschwig JP. Isolation of transverse tubules by fractionation of triad junctions of skeletal muscle. J Biol Chem 1977; 252:5565-74. [PMID: 142087] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
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Lau YH, Chiu TH, Caswell AH. Effects of beta-bungarotoxin on calcium uptake by sarcoplasmic reticulum from rabbit skeletal muscle. Biochem Biophys Res Commun 1974; 61:510-6. [PMID: 4455232 DOI: 10.1016/0006-291x(74)90986-3] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
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