INTRODUCTION: Elevated troponin, while essential for diagnosing myocardial infarction, can also be present in non-myocardial infarction conditions. The myocardial-ischaemic-injury-index (MI3) algorithm is a machine learning algorithm that considers age, sex and cardiac troponin I (TnI) results to risk-stratify patients for type 1 myocardial infarction. METHOD: Patients aged ≥25 years who presented to the emergency department (ED) of Singapore General Hospital with symptoms suggestive of acute coronary syndrome with no diagnostic 12-lead electrocardiogram (ECG) changes were included. Participants had serial ECGs and high-sensitivity troponin assays performed at 0, 2 and 7 hours. The primary outcome was the adjudicated diagnosis of type 1 myocardial infarction at 30 days. We compared the performance of MI3 in predicting the primary outcome with the European Society of Cardiology (ESC) 0/2-hour algorithm as well as the 99th percentile upper reference limit (URL) for TnI. RESULTS: There were 1351 patients included (66.7% male, mean age 56 years), 902 (66.8%) of whom had only 0-hour troponin results and 449 (33.2%) with serial (both 0 and 2-hour) troponin results available. MI3 ruled out type 1 myocardial infarction with a higher sensitivity (98.9, 95% confidence interval [CI] 93.4-99.9%) and similar negative predictive value (NPV) 99.8% (95% CI 98.6-100%) as compared to the ESC strategy. The 99th percentile cut-off strategy had the lowest sensitivity, specificity, positive predictive value and NPV. CONCLUSION The MI3 algorithm was accurate in risk stratifying ED patients for myocardial infarction. The 99th percentile URL cut-off was the least accurate in ruling in and out myocardial infarction compared to the other strategies.
Humans ; Male ; Female ; Emergency Service, Hospital ; Middle Aged ; Electrocardiography ; Machine Learning ; Singapore ; Chest Pain/blood* ; Troponin I/blood* ; Myocardial Infarction/blood* ; Risk Assessment/methods* ; Aged ; Algorithms ; Acute Coronary Syndrome/blood* ; Adult ; Sensitivity and Specificity

Less invasive transcatheter tricuspid therapies are optimal alternative for surgery in high-risk individuals with severe symptomatic tricuspid regurgitation on medical therapy. Various techniques are available with Transcatheter Edge-to-Edge Repair (TEER) having the greatest experience worldwide. When the coaptation gap becomes too large for TEER, caval valve implantation (CAVI) emerge as a better option. We described a series of 4 patients who underwent CAVI with the TricValve system and periprocedural computed tomography angiography imaging for the purpose of TricValve sizing. There were few procedural complications, with significant improvements in New York Heart Association functional class and right ventricular function post-procedure.

INTRODUCTION: Prognostic thresholds for 30-day major adverse cardiac events (MACE) have been studied for high-sensitivity troponin T (hsTnT) in patients with suspected acute coronary syndrome (ACS), but there is limited data on the prognostic performance of hsTnT for one-year MACE. METHODS: We prospectively measured hsTnT (in ng/mL up to two decimal places) at 0, 2 and 7 hours for patients presenting with symptoms suggestive of ACS to our emergency department from March 2010 to April 2013. We assessed the prognostic performance of hsTnT cut-offs for 30-day and one-year MACE, and the utility of delta-hsTnT in predicting MACE. RESULTS: Among 2,444 patients studied, 273 (11.2%) developed MACE (including index MACE) by 30 days and 359 (14.7%) patients developed MACE at one year. The suggested hsTnT cut-off for 30-day MACE was ≥ 10 ng/L at 0 hour (positive predictive value [PPV] 33.5%, negative predictive value [NPV] 94.5%) and 7 hours (PPV 37.3%, NPV 94.5%), and ≥ 20 ng/L at 2 hours (PPV 36.9%, NPV 96.9%). For one-year MACE, the suggested cut-off was also ≥ 10 ng/L at all readings. Plasma hsTnT ≥ 30 ng/L at any reading gave PPV > 54% and NPV > 93% for 30-day MACE. Absolute 0-2 hour and 2-7 hour delta-hsTnT ≥ 10 ng/L gave PPV > 50% for 30-day and one-year MACE. CONCLUSION Patients with 0-, 2- or 7-hour hsTnT ≥ 30 ng/L and 0-2 hour delta-hsTnT ≥ 10 ng/L had PPV > 50% for 30-day and one-year MACE, and should be investigated thoroughly.

INTRODUCTION: This study aimed to compare the incidence and mortality of ST-segment elevation myocardial infarction (STEMI) across the 3 main ethnic groups in Singapore, determine if there is any improvement in trends over the years and postulate the reasons underlying the ethnic disparity. MATERIALS AND METHODS: This study consisted of 16,983 consecutive STEMI patients who sought treatment from all public hospitals in Singapore from 2007 to 2014. RESULTS: Compared to the Chinese (58 per 100,000 population in 2014), higher STEMI incidence rate was consistently observed in the Malays (114 per 100,000 population) and Indians (126 per 100,000 population). While the incidence rate for the Chinese and Indians remained relatively stable over the years, the incidence rate for the Malays rose slightly. Relative to the Indians (30-day and 1-year all-cause mortality at 9% and 13%, respectively, in 2014), higher 30-day and 1-year all-cause mortality rates were observed in the Chinese (15% and 21%) and Malays (13% and 18%). Besides the Malays having higher adjusted 1-year all-cause mortality, all other ethnic disparities in 30-day and 1-year mortality risk were attenuated after adjusting for demographics, comorbidities and primary percutaneous coronary intervention. CONCLUSION It is important to continuously evaluate the effectiveness of existing programmes and practices as the aetiology of STEMI evolves with time, and to strike a balance between prevention and management efforts as well as between improving the outcome of "poorer" and "better" STEMI survivors with finite resources.

INTRODUCTION: Patients referred for chest pain from primary care have increased, along with demand for outpatient cardiology consultations. We evaluated 'Triage Protocol' that implements standardised diagnostic testing prior to patients' first cardiology consultation. MATERIALS AND METHODS: Under the 'Triage Protocol', patients referred for chest pain were pretriaged using a standardised algorithm and subsequently referred for relevant functional diagnostic cardiology tests before their initial cardiology consultation. At the initial cardiology consultation scheduled by the primary care provider, test results were reviewed. A total of 522 triage patients (mean age 55 ± 13, male 53%) were frequency-matched by age, gender and risk cohort to 289 control patients (mean age: 56 ± 11, male: 52%). Pretest risk of coronary artery disease was defined according to a Modified Duke Clinical Score (MDCS) as low (<10), intermediate (10-20) and high (>20). The primary outcome was time from referral to diagnosis (days). Secondary outcomes were total visits, discharge rate at first consultation, patient cost and adverse cardiac outcomes. RESULTS: The 'Triage Protocol' resulted in shorter times from referral to diagnosis (46 vs 131 days; <0.0001) and fewer total visits (2.4 vs 3.0; <0.0001). However, triage patients in low-risk groups experienced higher costs due to increased testing (S$421 vs S$357, = 0.003). Adverse cardiac event rates under the 'Triage Protocol' indicated no compromise to patient safety (triage vs control: 0.57% vs 0.35%; = 1.000). CONCLUSION By implementing diagnostic cardiac testing prior to patients' first specialist consultation, the 'Triage Protocol' expedited diagnosis and reduced subsequent visits across all risk groups in ambulatory chest pain patients.
Algorithms ; Cardiology Service, Hospital ; Chest Pain ; therapy ; Clinical Protocols ; Female ; Humans ; Male ; Middle Aged ; Primary Health Care ; Treatment Outcome ; Triage ; methods

INTRODUCTIONEarly use of mechanical cardiopulmonary resuscitation (CPR) for out-of-hospital cardiac arrest (OHCA) may improve survival outcomes. Current evidence for such devices uses outcomes from an intention-to-treat (ITT) perspective. We aimed to determine whether early use of mechanical CPR using a LUCAS 2 device results in better outcomes.

METHODSA prospective, randomised, multicentre study was conducted over one year with LUCAS 2 devices in 14 ambulances and manual CPR in 32 ambulances to manage OHCA. The primary outcome was return of spontaneous circulation (ROSC). Secondary outcomes were survival at 24 hours, discharge from hospital and 30 days.

RESULTSOf the 1,274 patients recruited, 1,191 were eligible for analysis. 889 had manual CPR and 302 had LUCAS CPR. From an ITT perspective, outcomes for manual and LUCAS CPR were: ROSC 29.2% and 31.1% (odds ratio [OR] 1.09, 95% confidence interval [CI] 0.82-1.45; p = 0.537); 24-hour survival 11.2% and 13.2% (OR 1.20, 95% CI 0.81-1.78; p = 0.352); survival to discharge 3.6% and 4.3% (OR 1.20, 95% CI 0.62-2.33; p = 0.579); and 30-day survival 3.0% and 4.0% (OR 1.32, 95% CI 0.66-2.64; p = 0.430), respectively. By as-treated analysis, outcomes for manual, early LUCAS and late LUCAS CPR were: ROSC 28.0%, 36.9% and 24.5%; 24-hour survival 10.6%, 15.5% and 8.2%; survival to discharge 2.9%, 5.8% and 2.0%; and 30-day survival 2.4%, 5.8% and 0.0%, respectively. Adjusted OR for survival with early LUCAS vs. manual CPR was 1.47 after adjustment for other variables (p = 0.026).

CONCLUSIONThis study showed a survival benefit with LUCAS CPR as compared to manual CPR only, when the device was applied early on-site.

INTRODUCTIONPeak currents are the final arbiter of defibrillation in patients with ventricular fibrillation (VF). However, biphasic defibrillators continue to use energy in joules for electrical conversion in hopes that their impedance compensation properties will address transthoracic impedance (TTI), which must be overcome when a fixed amount of energy is delivered. However, optimal peak currents for conversion of VF remain unclear. We aimed to determine the role of peak current and optimal peak levels for conversion in collapsed VF patients.

METHODSAdult, non-pregnant patients presenting with non-traumatic VF were included in the study. All defibrillations that occurred were included. Impedance values during defibrillation were used to calculate peak current values. The endpoint was return of spontaneous circulation (ROSC).

RESULTSOf the 197 patients analysed, 105 had ROSC. Characteristics of patients with and without ROSC were comparable. Short duration of collapse < 10 minutes correlated positively with ROSC. Generally, patients with average or high TTI converted at lower peak currents. 25% of patients with high TTI converted at 13.3 ± 2.3 A, 22.7% with average TTI at 18.2 ± 2.5 A and 18.6% with low TTI at 27.0 ± 4.7 A (p = 0.729). Highest peak current conversions were at < 15 A and 15-20 A. Of the 44 patients who achieved first-shock ROSC, 33 (75.0%) received < 20 A peak current vs. > 20 A for the remaining 11 (25%) patients (p = 0.002).

CONCLUSIONFor best effect, priming biphasic defibrillators to deliver specific peak currents should be considered.

The main areas of emphasis in the Advanced Cardiac Life Support (ACLS) guidelines are: early recognition of cardiac arrest and call for help; good-quality chest compressions; early defibrillation when applicable; early administration of drugs; appropriate airway management ensuring normoventilation; and delivery of appropriate post-resuscitation care to enhance survival. Of note, it is important to monitor the quality of the various care procedures. The resuscitation team needs to reduce unnecessary interruptions to chest compressions in order to maintain adequate coronary perfusion pressure during the ACLS drill. In addition, the team needs to continually look out for reversible causes of the cardiac arrest.

The Ministry of Health (MOH) has updated the Clinical Practice Guidelines on Lipids to provide doctors and patients in Singapore with evidence-based treatment for lipids. This article reproduces the introduction and executive summary (with recommendations from the guidelines) from the MOH Clinical Practice Guidelines on Lipids, for the information of SMJ readers. Chapters and page numbers mentioned in the reproduced extract refer to the full text of the guidelines, which are available from the Ministry of Health website: http://www.moh.gov.sg/content/moh_web/healthprofessionalsportal/doctors/guidelines/cpg_medical.html.
Adult ; Cardiovascular Diseases ; complications ; therapy ; Child ; Coronary Artery Disease ; complications ; therapy ; Decision Support Systems, Clinical ; Dyslipidemias ; blood ; complications ; therapy ; Evidence-Based Medicine ; Female ; Humans ; Kidney Failure, Chronic ; complications ; therapy ; Life Style ; Lipids ; blood ; Lipoproteins, LDL ; blood ; Male ; Practice Guidelines as Topic ; Pregnancy ; Pregnancy Complications ; Risk Assessment ; Risk Factors ; Singapore

INTRODUCTIONDoor-to-balloon (DTB) time is critical to ST elevation myocardial infarction (STEMI) patients' survival. Although DTB time is reduced with direct cardiovascular laboratory (CVL) activation by emergency physicians, concerns regarding false-positive activation remain. We evaluate false-positive rates before and after direct CVL activation and factors associated with false-positive activations.

MATERIALS AND METHODSThis is a retrospective single centre study of all emergency CVL activation 3 years before and after introduction of direct activation in July 2007. False-positive activation is defined as either: 1) absence of culprit vessel with coronary artery thrombus or ulceration, or 2) presence of chronic total occlusion of culprit vessel, with no cardiac biomarker elevations and no regional wall abnormalities. All false-positive cases were verified by reviewing their coronary angiograms and patient records.

RESULTSA total of 1809 subjects were recruited; 84 (4.64%) identified as false-positives. Incidence of false-positive before and after direct activation was 4.1% and 5.1% respectively, which was not significant (P = 0.315). In multivariate logistic regression analysis, factors associated with false-positive were: female (odds ratio (OR): 2.104 [1.247-3.548], P = 0.005), absence of chest pain (OR: 5.369 [3.024-9.531], P <0.0001) and presence of only left bundle branch block (LBBB) as indication for activation (OR: 65.691 [19.870-217.179], P <0.0001).

CONCLUSIONImprovement in DTB time with direct CVL activation by emergency physicians is not associated with increased false-positive activations. Factors associated with false-positive, especially lack of chest pain or LBBB, can be taken into account to optimise STEMI management.

Bundle-Branch Block ; epidemiology ; Cardiac Catheterization ; Chest Pain ; epidemiology ; Coronary Angiography ; Disease Management ; Emergency Medicine ; Humans ; Logistic Models ; Multivariate Analysis ; Percutaneous Coronary Intervention ; Physicians ; Retrospective Studies ; ST Elevation Myocardial Infarction ; diagnosis ; epidemiology ; therapy ; Sex Factors ; Singapore ; epidemiology ; Time-to-Treatment