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BackgroundAcute myocardial infarction (AMI) cases have decreased in part due to the advent of targeted therapies for standard modifiable cardiovascular disease risk factors (SMuRF). Recent studies have reported that ST-elevation myocardial infarction (STEMI) patients without SMuRF (termed “SMuRF-less”) may be increasing in prevalence and have worse outcomes than “SMuRF-positive” patients. As these studies have been limited to STEMI and comprised mainly Caucasian cohorts, we investigated the changes in the prevalence and mortality of both SMuRF-less STEMI and non-STEMI (NSTEMI) patients in a multiethnic Asian population.MethodsWe evaluated 23,922 STEMI and 62,631 NSTEMI patients from a national multiethnic registry. Short-term cardiovascular and all-cause mortalities in SMuRF-less patients were compared to SMuRF-positive patients.ResultsThe proportions of SMuRF-less STEMI but not of NSTEMI have increased over the years. In hospitals, all-cause and cardiovascular mortality and 1-year ...

ObjectiveTo reduce nationwide door-to-balloon times (DTB) in patients presenting with acute ST-elevation myocardial infarction (STEMI) requiring primary percutaneous coronary intervention (PCI), by adoption of pre-hospital wireless 12-lead electrocardiogram (ECG) transmission by Singapore's national ambulance service.MethodsA phased, prospective, before-after, interventional study of all patients who presented to the national ambulance service with the diagnosis of STEMI. In the ‘Before’ phase, chest pain patients only received 12-lead ECGs on arrival at the Emergency Departments (ED), where diagnosis of STEMI could be made. In the ‘After’ phase, 12-lead ECGs were performed in the field by ambulance crews and transmitted while en-route to the hospitals. Diagnoses of STEMI was made by on-duty emergency physicians (EP) prior to patients' arrival and PCI activated. Data was collected from ambulance run sheets, ECG transmission logs, EDs and cardiology units.Results451 eligible ...

BackgroundCurrent recommendations by cardiac implantable electronic devices (CIEDs) manufacturers on electromagnetic interference (EMI) are based on extrapolations of studies exposing CIEDs to electromagnetic fields produced by Helmholtz coils and industrial equipment. There are currently little data whether commercially available electronic massagers can cause EMI in CIEDs in vivo. This is of interest as the use of electronic massagers is common in Asia.MethodsThe study evaluated CIED patients before, during and after a 10‐minute exposure to a commercially available electronic backrest upper body massager. Post‐exposure sensing, pacing threshold, and lead impedance were compared to baseline values. The presence of artefacts, EMI, and adverse clinical events during exposure was recorded.ResultsEighty‐six patients (59 pacemakers and 27 implantable cardioverter‐defibrillators) with a total of 151 leads (60 atrial, 86 right ventricular, and 5 left ventricular) were evaluated. There was...

Risk stratification plays a key role in identifying acute myocardial infarction (AMI) patients at higher risk of mortality. However, current AMI risk scores such as the Global Registry of Acute Coronary Events (GRACE) score were derived from predominantly Caucasian populations and may not be applicable to Asian populations. We previously developed an AMI risk score from the national-level Singapore Myocardial Infarction Registry (SMIR) confined to ST-segment elevation myocardial infarction (STEMI) patients and did not include non-STEMI (NSTEMI) patients. Here, we derived a modified SMIR risk score for both STEMI and NSTEMI patients and compared its performance to the GRACE 2.0 score for predicting 1-year all-cause mortality in our multi-ethnic population. The most significant predictor of 1-year all-cause mortality in our population using the GRACE 2.0 score was cardiopulmonary resuscitation on admission (adjusted hazards ratio [HR] 6.50), while the most significant predictor using ...

Introduction: Acute myocardial infarction (MI) and acute ischaemic stroke (AIS) are leading causes of morbidity and mortality. There is scarce data examining the interplay between post-MI left ventricular systolic dysfunction (LVSD), with or without atrial fibrillation (AF), and subsequent AIS, especially in patients with milder degrees of LVSD (ejection fraction 40-49%). Evidence of an association would be helpful in developing new strategies of reducing AIS after MI. As such, we sought to study this relationship in a real-world population-based registry. Methods: This study involved linking national-level data from the Singapore Myocardial Infarction Registry with the Singapore Stroke Registry from 1st January 2007 to 31st December 2018. Both data sets have similar definitions for patient demographics. The ejection fraction (EF) and AF status were recorded during the MI episode. The outcome studied was the first instance of AIS that developed after the MI episode. We also studied ...

Smoking is one of the leading risk factors for cardiovascular diseases, including ischemic heart disease and hypertension. However, in acute myocardial infarction (AMI) patients, smoking has been associated with better clinical outcomes, a phenomenon termed the “smoker’s paradox.” Given the known detrimental effects of smoking on the cardiovascular system, it has been proposed that the beneficial effect of smoking on outcomes is due to age differences between smokers and non-smokers and is therefore a smoker’s pseudoparadox. The aim of this study was to evaluate the association between smoking status and clinical outcomes in ST-segment elevation (STEMI) and non-STEMI (NSTEMI) patients treated by percutaneous coronary intervention (PCI), using a national multi-ethnic Asian registry. In unadjusted analyses, current smokers had better clinical outcomes following STEMI and NSTEMI. However, after adjusting for age, the protective effect of smoking was lost, confirming a smoker’s pseudopa...

To determine the extent to which genetic variation in the potassium channel gene KCNQ1 causes atrial fibrillation (AF). Case-control study. National University Hospital, Singapore. Han Chinese patients (n=111) with lone AF (onset <60 years and lacking risk factors) and 265 Han Chinese controls. Blood draw, 12-lead electrocardiogram and transthoracic echocardiogram were performed on patients with AF at enrolment. DNA sequence variants in the coding region and exon-intron boundaries of KCNQ1 as detected by direct sequencing. Four previously reported coding variants were identified: I145I, S546S, P448R and G643S. An additional 19 non-coding variants were identified, nine of which are newly reported. None were predicted to create a cryptic splicing site. The allele frequencies of the two non-synonymous variants did not differ significantly in the AF cases compared with 265 Han Chinese controls (P448R: 10.8% in cases vs 8.6% in controls, p=0.41; G643S: 1.4% in cases vs 0.8% in control...

In the thrombolytic era, it was reported that in the presence of significant coronary stenosis, lowering diastolic blood pressure (DBP) below a critical threshold would result in a paradoxical increase in the occurrence of myocardial infarction (MI). We sought to re-evaluate this J-shaped relation in the era of pharmacoinvasive therapy. A total of 182 patients who underwent early (<1 week, mean 2.3 days) coronary angioplasty after thrombolysis were analysed. Thrombolytic agents (streptokinase in 60%, tissue plasminogen activator in 40%) were administered in an average door-to-needle time of 66 min (<=30 min in 43 [24%] patients). A thrombolysis in myocardial infarction (TIMI) 3 flow was achieved in 56% of patients after thrombolysis, and it was enhanced to 92% after angioplasty. During an average follow-up period of 26 +/-13 months, the adverse event (death, re-MI, target vessel revascularisation or stroke) rate was 21%. Older age, low systolic blood pressure and DBP, fast heart rate, high creatine kinase, hypercholesterolaemia, thrombus-laden lesion, baseline TIMI 0-2 flow were associated with higher occurrence of adverse events. After adjusting for the differing clinical and procedural factors, low DBP (odds ratio 1.10, 95% confidence interval 1.01-1.20, P = 0.041), fast heart rate (odds ratio 1.08, 95% confidence interval 1.02-1.14, P = 0.008) and anterior MI (odds ratio 18.98, 95% confidence interval 2.13-169.19, P = 0.008) were all independent predictors of long-term adverse rate occurrence. A low DBP is an independent predictor of long-term adverse event rates in patients undergoing routine early coronary angioplasty after thrombolysis. This suggests that excessive lowering of DBP may not be desirable before complete revascularisation.

Purpose – 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. Design/methodology/approach – 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. Findings – For 12 months after fully implementing the interventions, UE incid...

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.

Introduction: This study aims to study how the effect of the location of patient collapses from cardiac arrest, in the residential and non-residential areas within Singapore, relates to certain survival outcomes. Materials and Methods: A retrospective cohort study of data were done from the Cardiac Arrest and Resuscitation Epidemiology (CARE) project. Out-of-hospital cardiac arrest (OHCA) data from October 2001 to October 2004 (CARE) were used. All patients with OHCA as confirmed by the absence of a pulse, unresponsiveness and apnoea were included. All events had occurred in Singapore. Analysis was performed and expressed in terms of the odds ratio (OR) and the corresponding 95% confidence interval (CI). Results: A total of 2375 cases were used for this analysis. Outcomes for OHCA in residential areas were poorer than in non-residential areas—1638 (68.9%) patients collapsed in residential areas, and 14 (0.9%) survived to discharge. This was significantly less than the 2.7% of patien...

Background Stress-induced hyperglycaemia at time of hospital admission has been linked to worse prognosis following acute myocardial infarction (AMI). In addition to glucose, other glucose-related indices, such as HbA1c, glucose-HbA1c ratio (GHR), and stress-hyperglycaemia ratio (SHR) are potential predictors of clinical outcomes following AMI. However, the optimal blood glucose, HbA1c, GHR, and SHR cut-off values for predicting adverse outcomes post-AMI are unknown. As such, we determined the optimal blood glucose, HbA1c, GHR, and SHR cut-off values for predicting 1-year all cause mortality in diabetic and non-diabetic ST-segment elevation myocardial infarction (STEMI) and non-ST-segment elevation myocardial infarction (NSTEMI) patients. Methods We undertook a national, registry-based study of patients with AMI from January 2008 to December 2015. We determined the optimal blood glucose, HbA1c, GHR, and SHR cut-off values using the Youden’s formula for 1-year all-cause mortality. We...

Background Stress-induced hyperglycaemia at time of hospital admission has been linked to worse prognosis following acute myocardial infarction (AMI). The stress-hyperglycaemia ratio (SHR) index normalises the acute increase in blood glucose values to background glycaemic status. However, the optimal cut-off blood glucose and SHR values for predicting adverse outcomes post-AMI are unknown. As such, we determined the optimal blood glucose and SHR cut-offs for predicting 1-year all cause mortality in diabetic and non-diabetic non-ST-segment elevation myocardial infarction (NSTEMI) and ST-segment elevation myocardial infarction (STEMI) patients. Methods We undertook a national, registry-based study of patients with AMI from January 2008 to December 2015. We determined the optimal blood glucose and SHR cut-off values using the Youden’s formula for 1-year all-cause mortality. We subsequently analyzed the sensitivity, specificity, positive and negative predictive values of the cut-offs in...

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 a...

Lowering low-density lipoprotein (LDL-C) and triglyceride (TG) levels form the cornerstone approach of cardiovascular risk reduction, and a higher high-density lipoprotein (HDL-C) is thought to be protective. However, in acute myocardial infarction (AMI) patients, higher admission LDL-C and TG levels have been shown to be associated with better clinical outcomes - termed the ‘lipid paradox’. We studied the relationship between lipid profile obtained within 72 hours of presentation, and all-cause mortality (during hospitalization, at 30-days and 12-months), and rehospitalization for heart failure and non-fatal AMI at 12-months in ST-segment elevation myocardial infarction (STEMI) and non-ST-segment elevation myocardial infarction (NSTEMI) patients treated by percutaneous coronary intervention (PCI). We included 11543 STEMI and 8470 NSTEMI patients who underwent PCI in the Singapore Myocardial Infarction Registry between 2008–2015. NSTEMI patients were older (60.3 years vs 57.7 years,...

Background Expediting reperfusion during primary percutaneous coronary intervention is aimed at salvaging myocardium in ST-segment–elevation myocardial infarction. Few studies have examined the relation between reperfusion time and heart failure (HF) events. Methods and Results: We studied 7597 patients undergoing primary percutaneous coronary intervention from 2007 to 2013 in the Singapore Myocardial Infarct Registry, which captures HF at admission, postadmission in-hospital HF, and HF rehospitalization. We studied the relation of first medical contact to deployment of first device to achieve reperfusion (FTD) time with in-hospital HF events and HF rehospitalization, with mortality modeled as a competing risk. At the population level, median FTD time decreased from 91 minutes (interquartile range, 69–114) in 2007 to 58 minutes (45–75) in 2013 ( P =0.001), whereas mortality remained unchanged (in-hospital: range 5.3%–7.3%; P =0.190 and 1-year: range 7.8%–10.9%; P =0.505). HF at admi...

Aims Acute myocardial infarction (AMI) and stroke are important causes of mortality and morbidity. Our aims are to determine the comparative epidemiology of AMI and ischaemic stroke; and examine the differences in cardiovascular outcomes or mortality occurring after an AMI or stroke. Methods and results The Singapore National Registry of Diseases Office collects countrywide data on AMI, stroke, and mortality. Index events of AMI and ischaemic stroke between 2007 and 2012 were identified. Patients were then matched for occurrences of subsequent AMI, stroke, or death within 1-year of the index event. There were 33 222 patients with first-ever AMI and 20 982 with first-ever stroke. AMI patients were significantly more likely to be men (66.3% vs. 56.9%), non-Chinese (32.1% vs. 24.1%), and smokers (43.1% vs. 38.6%), but less likely to have hypertension (65.6% vs. 79%) and hyperlipidaemia (61.1% vs. 65.5%), compared with stroke patients. In total 6.8% of the AMI patients had recurrent AMI...

Up to 30% of patients remain on anticoagulants or antiplatelet agents at the time of implantation of cardiac electronic devices [1]. The use of clopidogrel alone, dual antiplatelet therapy (DAPT) or intravenous heparin significantly increases the risk of hematoma post device implantation [2–4]. Then again, withholding anticoagulants or antiplatet therapy peri-operatively may result in thromboembolic complications. Surgicel® FibrillarTM Hemostat (Ethicon Inc. USA) is a form of oxidized regenerated cellulose (ORC), a plant-based topical hemostatic agent that is used adjunctively in surgical procedures to help control capillary, venous and small arterial hemorrhage when conventional methods of hemostasis are impractical [5,6]. It is fully absorbablewithin 14 days and has in-vitro bactericidal properties [6,7]. We describe a pilot series of 42 patients who received Surgicel® FibrillarTM Hemostat during implantation of cardiac pacemakers or defibrillators whilst remaining on anticoagulants or DAPT. We aim to assess the safety and efficacy of ORC in prevention of pocket hematomas in this group of individuals at high risk of bleeding complications postimplant. In our institution, patients on antiplatelet therapy or warfarin remain on these medications when they undergo implantation of cardiac pacemakers or defibrillators. The international normalized ratio (INR) is titrated to less than 3. A pocket hematoma is defined as a palpable mass that protrudes N2 cm (minor hematoma) or N4 cm (significant hematoma). Between 1 April 2012 and 31 January 2013, we identified 42 patients onwarfarin or DAPT inwhom implantation of cardiac electronic devices was indicated (See Table 1). Their mean age was 68 ± 8 years, 28 were males. Eighteen patients were onwarfarinwith a mean INR of 2.5 ± 0.2 peri-operatively. Of these 18 patients, 3 were on both warfarin and clopidogrel 75 mg daily. Twenty-four patients were on DAPT consisting of aspirin 100 mg and clopidogrel 75 mg daily. Each patient received 1 dose of intravenous cephazolin 1 h prior to the procedure. During implantation, a subcutaneous pocket was created in the pre-pectoral region with the use of electrocautery. All visible bleeding sites, especially arterial ones, were meticulously cauterized. Vascular access was obtained through subclavian or axillary venous punctures under fluoroscopy guidance. Each lead was implanted via a separate venous puncture. Following placement of the pulse generator in the pocket, Surgicel® FibrillarTM Hemostat was peeled off in the desired amount and the pieces fitted into the pocket, above and to the sides of the pulse generator. The wound was then closed in 2 layers with absorbable sutures and a sterile dressing applied. Each patient was prescribed a 1-week course of oral cephalexin post-implant. They were examined daily until hospital discharge and they returned for outpatient follow-up on Day 7 and 1 month postimplant for wound inspection and device check. Subsequent follow-up was at 3 to 6 monthly intervals. There was no case of pocket hematoma or infection with a mean follow-up period of 6 ±2.3 months. Despite the continued use of warfarin and DAPT peri-operatively, none of our patients developed pocket hematoma or infection. ORC appeared to be safe and effective in prevention of bleeding complications in high-risk individuals during device implantation. In the setting of anticogulation or DAPT, capillary or venous ooze is common. Conventional methods to achieve hemostasis may prove ineffective, especially in the confined areas of the subcutaneous pocket. The benefit of topical hemostatic agents in such settings is controversial. Milic et al. reported that the administration of fibrin sealant in patients on anticoagulation eliminated post-operative pocket hematomas after pacemaker implantation [8]. Recently, Ohlow et al. published data showing that the use of D-Stat HemostatTM (Vascular Solutions Inc. USA) tended towards a higher incidence of pocket hematoma requiring evacuation and pocket infections [9]. ORC is ready for use straight out of the packaging. It can be cut or peeled into customized sizes and fitted into the subcutaneous pocket. It provides a matrix for platelet adhesion and aggregation by melting into bleeding tissue, thereby serving as a hemostatic adjunct in the control of capillary, venous and small arterial hemorrhage. It is fully absorbed from the sites of implantation within 1 to 2 weeks with no tissue reaction. In-vitro studies highlight its bactericidal properties [7]. Given such features, ORC may potentially be suitable as a topical hemostat during cardiac electronic device implantation. Our study is limited by its small sample size and non-randomized design with no control arm. Large randomized trials comparing ORC versus standard care are necessary to fully evaluate the effectiveness and

A 76-year-old male subject with a long standing history of hypertension was referred to the cardiology clinic for poorly controlled high blood pressure despite good drug compliance (figure 1A). He had multiple cardiovascular comorbidities like diabetes mellitus, ischaemic heart disease and hyperlipidaemia. His antihypertensive regimen constituted of a thiazide …

Introduction: There is limited information on elderly patients presenting with ST elevation myocardial infarction (STEMI). This study aimed to study the outcomes of elderly Asian patients with STEMI compared to younger patients. Materials and Methods: The study utilised data from 2007 to 2012 from the Singapore Myocardial Infarction Registry, a mandatory national population-based registry. Elderly patients were defined as ≥80 years of age, middle-aged to old (MAO) patients were defined as 45–80 years of age and young patients were defined as ≤45 years of age. The primary outcome of the study was 1-year mortality and secondary outcomes included in-hospital complications and mortality. Results: There were 12,409 STEMI patients with 1207 (9.7%) elderly patients, 10,093 (81.3%) MAO patients and 1109 (8.9%) young patients. Elderly patients had more cardiovascular risk factors and lower rates of total percutaneous coronary intervention (26.0% vs 72.4% vs 85.5%, respectively; P <0.0001)...