[Show abstract][Hide abstract] ABSTRACT: the purpose of this study was to investigate differences in long-term mortality following acute myocardial infarction (AMI) in patients from three major ethnicities of Asia.
We studied 15,151 patients hospitalized for AMI with a median follow-up of 7.3 years (maximum 12 years) in six publicly-funded hospitals in Singapore from 2000-2005. Overall and cause-specific cardiovascular (CV) mortality until 2012 were compared among three major ethnic groups that represent large parts of Asia: Chinese, Malay and Indian. Relative survival of all three ethnic groups was compared with a contemporaneous background reference population using the relative survival ratio (RSR) method. The median global registry of acute coronary events score was highest among Chinese, followed by Malay and Indians: 144 (25th percentile 119, 75th percentile 173), 138 (115, 167), and 131 (109, 160), respectively, p<0.0001; similarly, in-hospital mortality was highest among Chinese (9.8%) followed by Malay (7.6%) and Indian (6.4%) patients. In contrast, 12-year overall and cause-specific CV mortality was highest among Malay (46.2 and 32.0%) followed by Chinese (43.0 and 27.0%) and Indian (35.9 and 25.2%) patients, p<0.0001. The five-year RSR was lowest among Malay (RSR 0.69) followed by Chinese (RSR 0.73) and Indian (RSR 0.79) patients, compared with a background reference population (RSR 1.00).
We observed strong inter-Asian ethnic disparities in long-term mortality after AMI. Malay patients had the most discordant relationship between baseline risk and long-term mortality. Intensified interventions targeting Malay patients as a high-risk group are necessary to reduce disparities in long-term outcomes.
European heart journal. Acute cardiovascular care. 03/2014;
[Show abstract][Hide abstract] ABSTRACT: Introduction: In Singapore, the age-standardised event rates of myocardial infarction (MI) are 2- and 3-fold higher for Malays and Indians respectively compared to the Chinese. The objectives of this study were to determine the prevalence and quantity of coronary artery calcification (CAC) and non-calcified plaques across these 3 ethnic groups. Materials and Methods: This was a retrospective descriptive study. We identified 1041 patients (810 Chinese, 139 Malays, 92 Indians) without previous history of cardiovascular disease who underwent cardiac computed tomography for atypical chest pain evaluation. A cardiologist, who was blinded to the patients' clinical demographics, reviewed all scans. We retrospectively analysed all their case records. Results: Overall, Malays were most likely to be active smokers (P = 0.02), Indians had the highest prevalence of diabetes mellitus (P = 0.01) and Chinese had the highest mean age (P <0.0001). The overall prevalence of patients with non-calcified plaques as the only manifestation of sub-clinical coronary artery disease was 2.1%. There was no significant difference in the prevalence of CAC, mean CAC score or prevalence of non-calcified plaques among the 3 ethnic groups. Active smoking, age and hypertension were independent predictors of CAC. Non-calcified plaques were positively associated with male gender, age, dyslipidaemia and diabetes mellitus. Conclusion: The higher MI rates in Malays and Indians in Singapore cannot be explained by any difference in CAC or non-calcified plaque. More research with prospective follow-up of larger patient populations is necessary to establish if ethnic-specific calibration of CAC measures is needed to adjust for differences among ethnic groups.
Annals of the Academy of Medicine, Singapore 09/2013; 42(9):432-6. · 1.36 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: BACKGROUND: Impaired renal function and anaemia are common among patients with acute myocardial infarction (AMI). While both conditions are known independent risk factors for increased mortality, their interaction as risk factors for increased mortality in AMI is unclear. METHODS: We studied 5395 subjects hospitalized for AMI between January 2000 and December 2005. An estimated glomerular filtration rate (GFR) <60mL/min/1.73m(2) was defined as impaired GFR and GFR ≥60mL/min/1.73m(2) was defined as preserved GFR. Anaemia was defined as <13g/dL (males) and <12g/dL (females). The odds ratio (OR) for one-year mortality and its 95% confidence interval (CI) were calculated by logistic regression. RESULTS: We identified 758 (14%) patients with impaired GFR and anaemia, 1105 (20.5%) patients with impaired GFR without anaemia, 465 (8.6%) patients with preserved GFR and anaemia, and 3012 (55.8%) patients with preserved GFR without anaemia; one-year mortality rates were 56.5%, 41.8%, 31.8% and 10.3% respectively in these 4 groups. Among patients with impaired GFR, anaemia was associated with an adjusted OR of 1.47 (95% CI=1.17-1.85) for one-year mortality, while among patients with preserved GFR, anaemia was associated with a higher adjusted OR of 2.07 (95% CI=1.54-2.76) for one-year mortality, interaction P<0.001. CONCLUSION: The combination of impaired GFR and anaemia confers greater than five-fold increased risk of mortality after AMI. The differential effect of anaemia among patients with impaired and preserved GFR on mortality suggests that in patients with preserved GFR anaemia confers a greater relative hazard than in patients with impaired renal function.
International journal of cardiology 01/2013; · 6.18 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: This article aims to explore coronary care unit (CCU) extubation structures, processes and outcomes. There were 13 unplanned-extubation cases (UE) among 251 intubated patients (5.2 per cent) in a cardiologist-led CCU in 2008. Seven did not require re-intubation, implying possible earlier extubation. A quality improvement project was undertaken with a goal to eliminate CCU UE within 12 months.
Using the clinical practice improvement (CPI) method, the most significant root causes were missing sedation/analgesia protocol, no ventilator weaning protocol and absent respiratory therapist during the CCU morning rounds. Non-physician directed sedation/analgesia and ventilation weaning protocols were created and put on trial in Plan-Do-Study-Act cycles before formal implementation. Arrangements were made to allocate a respiratory therapist to the CCU daily for morning rounds.
For 12 months after fully implementing the interventions, UE incidence dropped from 5.2 per cent to 0.9 per cent (p = 0.006). There were no adverse outcomes, re-intubation and/or readmission to CCU within 48 hours.
Through a multi-disciplinary CPI approach, adopting non-physician directed protocols has successfully streamlined and improved airway management in mechanically ventilated patients in a cardiologist-led CCU.
There is little published data on improving intubated patient care in cardiologist-led CCUs. Previous studies centered on intensive care units managed by critical care specialists.
International Journal of Health Care Quality Assurance 01/2013; 26(7):642-52.
[Show abstract][Hide abstract] ABSTRACT: Ventricular tachycardia (VT) storm is an uncommon but life-threatening condition. We describe the incidence, causes and management of VT storm among patients admitted to the coronary care unit of a large tertiary hospital.
Between 1 November 2009 and 30 April 2010, 198 patients were admitted to the coronary care unit and 7 (3.5%) presented with VT storm. A retrospective review of their records was conducted. The mean follow-up period was 268 (196 to 345) days.
The mean age was 67 years and 4 patients were male. One patient had a previous myocardial infarction. All had abnormal left ventricular ejection fraction, median of 30%. Acute myocardial infarction (4 patients) was the most common trigger, followed by decompensated heart failure (1), systemic inflammatory response syndrome on a background of non-ischemic dilated cardiomyopathy (1) and bradycardia-induced polymorphic VT (1). Three patients had polymorphic VT and the rest had monomorphic VT. Intravenous amiodarone, lignocaine, overdrive pacing and intra-aortic balloon pump counterpulsation were useful in arrhythmia control. Three patients underwent coronary revascularization, 3 patients received implantable cardioverter-defibrillators, 1 had a permanent cardiac pacemaker, 1 died during the acute episode. Five out of the 6 survivors were prescribed oral beta-blockers upon discharge. On follow-up, none of the patients had a recurrence of the tachyarrhythmia.
Acute myocardial infarction was the main trigger of VT storm in our patients. Intravenous amiodarone, lignocaine, overdrive pacing and intra-aortic balloon pump counterpulsation were useful at suppressing VT storm.
The Medical journal of Malaysia 12/2012; 67(6):582-4.
[Show abstract][Hide abstract] ABSTRACT: To investigate the clinical features and in-hospital outcomes of young adults with acute myocardial infarction (AMI) in Singapore.
Between January 2005 to September 2010, 333 consecutive patients aged ≤ 45 years old were diagnosed to have AMI at our institution. As Singapore is a multi-ethnic society, we also analysed whether ethnic differences exist between the three dominant ethnic groups, Malay, Chinese and Indian with regards to the clinical features. Clinical data was collected retrospectively on demographic characteristics, presenting signs and symptoms, blood investigation, angiographic findings and in-hospital clinical outcomes.
The mean age at presentation was 40.2 ± 4.0 years with male predominance (94%). The majority of patients were Chinese (51%) followed by Indians (31%) and Malays (18%). The most common risk factor was smoking (74%) followed by hypertension (28.5%) and hyperlipidemia (20.0%). 37% of patients were obese. The majority of patients had single vessel disease (46%) on coronary angiography. The mean total cholesterol, low-density lipoprotein and high-density lipoprotein levels were 5.6 ± 1.2 mmol/L, 3.8 ± 1.1 mmol/L and 0.93 ± 0.25 mmol/L respectively. The mean left ventricular function was 44% ± 10% with the incidence of heart failure 3% and cardiogenic shock 4.5%. Overall in-hospital mortality was low with 4 deaths (1.2%). For ethnic subgroup analysis, Indians have a 3-fold risk of developing premature AMI when compared to other ethnic groups.
Young AMI patients in Singapore are characterized by male predominance, high incidence of smoking and obesity. Overall in-hospital clinical outcomes are favourable. Among the 3 ethnic groups, Indians have the highest risk of developing premature AMI.
World Journal of Cardiology (WJC) 06/2012; 4(6):206-10. · 2.06 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Intracoronary bolus of eptifibatide during percutaneous coronary intervention (PCI) for acute myocardial infarction (AMI) has been shown to result in higher local platelet glycoprotein IIb/IIIa receptor occupancy with improved microvascular perfusion. It is unclear whether intracoronary administration of eptifibatide in a larger patient population results in favourable clinical outcomes. We evaluated the safety and efficacy of two regimens of intracoronary eptifibatide (bolus only versus bolus followed by intravenous infusion) in patients undergoing primary PCI for ST-elevation MI. They were divided into two groups: Group A (n=67) who received fixed-dose intracoronary eptifibatide bolus only and Group B (n=88) who received intracoronary bolus and continuous intravenous infusion of eptifibatide for 18 h. The preliminary findings from our registry showed that both regimens were associated with good angiographic outcomes, few bleeding events and low in-hospital major adverse cardiac events. A large prospective randomized, multi-centre trial is needed to confirm our observation.
[Show abstract][Hide abstract] ABSTRACT: We report a patient with secondary aortoenteric fistula (AEF) presenting with a rectal bleeding. The patient had multiple comorbidities, precluding major open vascular surgery. We opted to perform a two-stage procedure, where an endovascular stent-graft was first deployed to exclude the AEF from the systemic circulation. As the AEF was at the proximal anastomosis of the previous Dacron graft and close to the renal artery ostia, chimney stent-grafts were placed in both renal arteries to maintain their patency. The second stage of the procedure involved a laparotomy to repair the defect in the duodenum to prevent further contamination from bowel contents.
Annals of Vascular Surgery 01/2012; 26(3):422.e13-6. · 0.99 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: We report the case of a 69 year-old Chinese lady with pheochromocytoma who developed chest pain and acute ST-segment elevation in the anterior leads on electrocardiography. She was given intravenous phenoxybenzamine for alpha-blockade before undergoing urgent coronary angiography. This revealed minor coronary artery disease. Left ventriculogram demonstrated akinesis in the apex with hypercontraction of the basal segments. The Tako-tsubo cardiomyopathy eventually resolved with surgical removal of the pheochromocytoma. This case highlights the challenging management of suspected acute myocardial infarction in pheochromocytoma crisis and also reinforces the notion that Tako-tsubo cardiomyopathy is likely precipitated by catecholamine excess.