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Objective: This study aims to examine the efficacy of a hypertension awareness education program in Singapore in reaching out to a wider population of diverse racial and intergenerational cohorts by dispatching grade five children as information intermediaries to their immediate and extended family members.Method: After receiving structured instruction and training on blood pressure screening, students were requested to share knowledge gained in school with their family members at home and practice blood pressure measurement on family volunteers. We assessed pre- and post-program blood pressure knowledge change, attitude toward screening, and the diffusion of blood pressure information. One adult family member was also asked to complete a short survey at the program end.Results: A comparison of the students' (final n = 3926) pre- and post-program survey data showed that knowledge and attitudes towards knowledge sharing improved after participating in the program. The post-program survey also revealed that students generally felt confident and displayed positive attitudes in performing blood pressure screening on family members. On average, each student practiced blood pressure measurement on 3.04 people. Female family members were more likely to be targeted for knowledge sharing and screening than male family members. The family members' survey revealed positive attitudes towards screening, but family members were not confident about getting their measurements done regularly.Conclusion: The program met its objectives in raising the awareness of grade five children and provision of knowledge. It also met the larger objective of raising hypertension awareness in a wider population, especially those who otherwise might not directly receive health education and blood pressure screening. [ABSTRACT FROM AUTHOR]

It is unclear whether universal access to primary percutaneous coronary intervention (pPCI) may reduce sex differences in 1-year rehospitalization for heart failure (HF) and myocardial infarction (MI) after ST-elevation myocardial infarction (STEMI). We studied 7,597 consecutive STEMI patients (13.8% women, n = 1,045) who underwent pPCI from January 2007 to December 2013. Cox regression models adjusted for competing risk from death were used to assess sex differences in rehospitalization for HF and MI within 1 year from discharge. Compared with men, women were older (median age 67.6 vs 56.0 years, p < 0.001) with higher prevalence of co-morbidities and multivessel disease. Women had longer median door-to-balloon time (76 vs 66 minutes, p < 0.001) and were less likely to receive drug-eluting stents (19.5% vs 24.1%, p = 0.001). Of the medications prescribed at discharge, fewer women received aspirin (95.8% vs 97.6%, p = 0.002) and P2Y 12 antagonists (97.6% vs 98.5%, p = 0.039), but there were no significant sex differences in other discharge medications. After adjusting for differences in baseline characteristics and treatment, sex differences in risk of rehospitalization for HF attenuated (hazard ratio [HR] 1.05, 95% confidence interval [CI] 0.79 to 1.40), but persisted for MI (HR 1.68, 95% CI 1.22 to 2.33), with greater disparity in patients aged ≥60 years (HR 1.83, 95% CI 1.18 to 2.85) than those aged <60 years (HR 1.45, 95% CI 0.84 to 2.50). In conclusion, in a setting of universal access to pPCI, the adjusted risk of 1-year rehospitalization for HF was similar in both sexes, but women had significantly higher adjusted risk of 1-year rehospitalization for MI, especially older women., (Copyright © 2019. Published by Elsevier Inc.)

Appropriate use criteria (AUC) for single-photon emission computed tomography myocardial perfusion images (SPECT-MPIs) were developed to address the growth of cardiac imaging studies. Long-term prognostic value of AUC in SPECT-MPI has not been tested in existing cohorts. We sought to determine the long-term prognostic value of MPI classified as appropriate. AUC was evaluated in a prospectively designed cohort of patients who underwent clinically indicated MPI. MPI studies were classified based on 2009 AUC for SPECT-MPI. Data regarding downstream coronary angiography (cath), revascularization and all-cause mortality, cardiac death, and nonfatal myocardial infarction (MI) were collected from national registries. Among n = 1,129 MPI scans that received an appropriate grading, 148 all-cause deaths, 109 MIs, 58 cardiac deaths, 152 caths, 113 revascularization procedures occurred over a mean follow-up period of 5.4 ± 1.2 years (0.9% cardiac death rate per year, 1.8% MI rate per year). Most of the scans were low-risk normal MPI scans (summed stress score ≤3; 74.1%). An abnormal scan was associated with higher rates of MI (19.5% vs 6.2%, hazard ratio 1.72, p = 0.017) and cardiac death (13.4% vs 2.3%, hazard ratio 2.12, p = 0.016). In conclusion, MPI scans classified as appropriate have long-term prognostic value, despite a high proportion of low-risk scans. This provides support for clinicians to consider the use of appropriate grading in addition to MPI scan results in patient management., (Copyright © 2017 Elsevier Inc. All rights reserved.)

Background: There is a clinical need for a contractility index that reflects myocardial contractile dysfunction even when ejection fraction (EF) is preserved. We used novel relative load-independent global and regional contractility indices to compare left ventricular (LV) contractile function in three groups: heart failure (HF) with preserved ejection fraction (HFPEF), HF with reduced ejection fraction (HFREF) and normal subjects. Also, we determined the associations of these parameters with 3-month and 1-year mortality in HFPEF patients., Methods: 199 HFPEF patients [median age (IQR): 75 (67-80) years] and 327 HFREF patients [69 (59-76) years] were recruited following hospitalization for HF; 22 normal control subjects [65 (54-71) years] were recruited for comparison. All patients underwent standard two-dimensional Doppler and tissue Doppler echocardiography to characterize LV dimension, structure, global and regional contractile function., Results: The median (IQR) global LV contractility index, dσ*/dtmax was 4.30s(-1) (3.51-4.57s(-1)) in normal subjects but reduced in HFPEF [2.57 (2.08-3.64)] and HFREF patients [1.77 (1.34-2.30)]. Similarly, median (IQR) regional LV contractility index was 99% (88-104%) in normal subjects and reduced in HFPEF [81% (66-96%)] and HFREF [56% (41-71%)] patients. Multi-variable logistic regression analysis on HFPEF identified sc-mFS <76% as the most consistent predictor of both 3-month (OR=7.15, p<0.05) and 1-year (OR=2.57, p<0.05) mortality after adjusting for medical conditions and other echocardiographic measurements., Conclusion: Patients with HFPEF exhibited decreased LV global and regional contractility. This population-based study demonstrated that depressed regional contractility index was associated with higher 3-month and 1-year mortality in HFPEF patients., (Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.)

Background/objectives: This study aims to examine iliofemoral anatomy and predictors of vessel size and tortuosity in Asian patients as transfemoral transcatheter aortic valve implantation (TAVI) may be limited by the smaller Asian physique., Methods: Characteristics and vessel dimensions of 549 patients undergoing ultrasonography were reviewed. The minimal luminal diameter (MLD) along the iliofemoral vasculature of each side was identified and the larger of the two sides was used to determine suitability for transfemoral TAVI., Results: The mean age was 66 ± 11 years (68% males). Mean iliac MLD was 7.6 ± 1.7 mm, females smaller than males (7.2 ± 1.7 vs 7.8 ± 1.7, p<0.001). Mean iliac MLD decreased with age: 7.9 ± 1.7 mm, 7.4 ± 1.9 mm and 7.3 ± 1.6mm for ages <70 years, 70-79 years and ≥ 80 years respectively (p=0.038). Mean femoral MLD was 7.0 ± 1.7 mm, females smaller than males (6.3 ± 1.5mm vs 7.3 ± 1.8mm, p<0.001). Females were more likely than males to have iliac and femoral MLD <6mm (20% vs 12%, p=0.019 and 34% vs 21%, p=0.001). Independent predictors of smaller iliofemoral dimensions were female gender, lower body surface area, diabetes mellitus, dyslipidemia and smoking history. Significant iliac tortuosity was present in 11.8%, more frequent in males than females (15% vs 6%, p=0.005), and in those with logistic EuroSCORE ≥ 15 than <15 (27% vs 10%, p=0.001)., Conclusions: This study establishes the mean iliac and femoral artery diameters in a cohort of relatively young Asian patients. Age and female gender were associated with smaller vessel dimension and several independent predictors of smaller vasculature and tortuosity were identified. These results have implications for TF TAVI in Asia., (Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.)

Aims: Resting 12-lead electrocardiograms (ECGs) have been employed in the pre-participation evaluation of young asymptomatic subjects to detect pre-existing heart diseases. Although the incorporation of routine ECG in pre-participation screening remains controversial, there is increasing evidence that cardiomyopathies and ion channelopathies have ECG changes as the initial manifestation. The causes of sudden cardiac death in young people show significant geographical variation. We aim to determine the prevalence and spectrum of ECG abnormalities in a young male South-East Asian population., Methods and Results: The Singapore Armed Forces Electrocardiogram and Echocardiogram (SAFE) protocol is an ECG-based pre-participation cardiac screening programme modelled after the Italian system. From October 2008 to May 2009, a total of 18 476 young male conscripts (mean age 19.5 years old, range 16-27) underwent mandatory pre-enlistment medical screening at a single medical facility. Subjects with abnormal ECG findings were classified into two groups: Group A had ECG changes that fulfilled a pre-specified checklist to screen for hypertrophic cardiomyopathy and were referred for transthoracic echocardiogram; Group B had other ECG abnormalities [such as Brugada pattern, Wolff-Parkinson-White (WPW) pattern, long QTc] and were referred for secondary screening at a tertiary institution. Of the 18 476 subjects screened, 7.0% (n= 1285) had ECG abnormalities. Of note, 19 (0.10%) had Brugada pattern, 25 (0.14%) had WPW pattern, and 31 (0.17%) had prolonged QT interval on ECG. The prevalence of ECG abnormalities was significantly higher in Chinese than in South Asians (7.2 vs. 5.7%, P= 0.003)., Conclusion: The prevalence of ECG abnormalities in a young, South-East Asian male population was 7.0%. There were significant ethnic differences, with ECG abnormalities more prevalent in Chinese than in South Asians (7.2 vs. 5.7%, P= 0.003). The inclusion of universal ECG, in addition to history and physical examination, may increase the sensitivity of a cardiovascular screening programme. Knowledge of the spectrum and prevalence of ECG abnormalities and disease conditions would be pivotal in designing customized screening programmes.

Objectives: To determine clinical outcome and rates of target vessel revascularization (TVR) in patients undergoing primary percutaneous coronary intervention (PCI) for STEMI who were treated with cobalt-chromium stents compared to stainless steel bare metal stents (BMS)., Background: The newer generation cobalt chromium stents were reported to achieve lower rates of TVR compared with conventional BMS., Methods: Consecutive STEMI cases admitted within 12 h of symptom onset and undergoing primary angioplasty and bare metal stent implantation 1 January 2002 and 31 December 2008 were identified. Primary outcomes were rates of clinically-driven TVR at six months as well as occurrence of major adverse cardiovascular events (MACE) either of all-cause death, repeat myocardial infarction or TVR at six months., Results: 1030 cases with 1175 lesions (84% males) and median age of 58 years underwent primary PCI for STEMI in our registry. Overall procedural success rate was 98%. Stainless steel stents were inserted in 65% of the culprit lesions (stainless steel, n = 766 versus cobalt chromium, n = 264). Primary outcomes of TVR (3.5% in the stainless steel group and 3.4% in the cobalt chromium group, P = 0.93) and MACE (8.4% in the stainless steel group and 5.3% in the cobalt chromium group, P = 0.11) after six months were no different between the two groups. However, there were more deaths at 30 days in the stainless steel group compared to the cobalt chromium group (3.5% versus 0.4%, HR 4.04 (1.03-3.88), P = 0.04)., Conclusion: Both cobalt-chromium and stainless steel coronary stents were associated with similar and low risk of clinically-driven TVR.

Aims: Hypertrophic cardiomyopathy is a leading cause of sudden cardiac death (SCD) in young people in the USA. Pre-participation screening for athletes might reduce the incidence of SCD. In Singapore, military service is compulsory for all young able-bodied male citizens. The Singapore Armed Forces Electrocardiogram and Echocardiogram (SAFE) pre-participation screening protocol based on the Italian programme was introduced. This study evaluates the prevalence of hypertrophic cardiomyopathy (HCM) in a young male South-East Asian population., Methods and Results: From October 2008 to May 2009, all male military conscripts underwent pre-participation screening. For all conscripts whose electrocardiogram (ECG) findings fulfilled any of these pre-specified criteria (Group A), direct referral for a transthoracic echocardiogram was mandatory. Conscripts with ECG findings other than pre-specified criteria (e.g. T-wave inversions, repolarization abnormalities) were referred for secondary screening by cardiologists (Group B), which could include echocardiography. Out of 18 476 subjects screened during the study period, 988 (5.3%) subjects were fast tracked for echocardiogram (Group A). Of them, there were three (0.3%) cases with severe abnormalities; there was one case each of HCM, bicuspid aortic valve with significant aortic valve regurgitation, and atrial septal defect with right ventricular systolic dysfunction. The patient with HCM had left axis deviation on ECG. None of the 215 patients who underwent echocardiography following cardiology consult (Group B) had HCM., Conclusion: The prevalence of HCM in our young male population (mean age 19.5, range 16-27) using an ECG-based screening protocol was 0.005%; this appeared lower than published data from other geographical cohorts. Possible explanations include a later age of phenotypic manifestation in our population, limitations of the ECG criteria for screening, or a truly lower prevalence of HCM. More population-based longitudinal studies would be needed to ascertain the true prevalence of HCM in our South-East Asian population.

Background and Aim: Drug-eluting stents (DESs) have been reported to be more efficacious compared with bare-metal stents (BMSs) in reducing the need for target vessel revascularization (TVR). However, the long-term benefits for patients with diabetes with small vessel disease are less certain. We aim to determine the clinical outcome of patients with diabetes with diffuse small vessel coronary artery disease who undergo percutaneous coronary intervention., Methods: This is a single-center prospective registry of all patients with diabetes with target lesions implanted with stents that were 2.25 mm or less in diameter and approximately 20 mm in total stent length between January 2002 and October 2008. Primary outcome was combined major adverse cardiovascular events: death, nonfatal myocardial infarction and TVR up to 5 years. Outcomes were adjusted for age, sex and cardiovascular risk factors., Results: There were 544 patients (63% males, mean age 62±10 years) with 1010 lesions that were followed up for a mean duration of 3±2 years. Two hundred and thirty-nine patients (439 lesions) received BMS whereas 305 (571 lesions) received DES. DES lesions were longer (mean length 23.3±6.96 vs. 17.8±5.02 mm, P<0.001) than BMS lesions. Procedural success was similar for BMS and DES patients (86.2 vs. 86.6%, P=0.90). DES patients had less TVR at 6 months [3.9 vs. 9.2%, odds ratio (OR): 4.90, 95% confidence interval (CI): 1.53-15.65, P=0.007], 1 year (1 vs. 3.8%, OR: 8.01, 95% CI: 1.25-51.10, P=0.028) and 3 years (13.8 vs. 18.0%, OR: 5.50, 95% CI: 3.74-8.13, P=0.043). By 5 years, the primary outcome was lower in DES patients (21.6 vs. 28%, OR: 1.79, 95% CI: 1.14-2.80, P=0.011). Independent predictors of TVR at 6 months were above or equal to 59 years of age (OR: 0.95, 95% CI: 0.90-1.00, P=0.032) and use of glycoprotein-IIbIIIa inhibitors (OR: 0.02, 95% CI: 0.001-0.50, P=0.018). Stent length was not a significant predictor of TVR., Conclusion: Our observational analysis suggests that DES seems to have short-term and mid-term advantages over BMS in reducing TVR and overall major adverse cardiovascular events. Percutaneous coronary intervention with DES may be considered as an option in these patients with limited revascularization options.

Risk prediction models are critical in managing patients with acute coronary syndromes (ACS) as they identify high-risk patients who benefit the most from targeted care. We discuss the process of developing and validating a risk prediction model as well as highlight the more commonly used models in clinical practice currently. Finally we conclude by outlining the importance of creating a risk prediction model based on a Singapore population of ACS patients so as to further improve patient, hospital and research outcomes.

Introduction: The study was designed to reduce door-to-balloon times in primary percutaneous coronary intervention for patients presenting to the Emergency Department with acute ST-elevation myocardial infarction, using an audit as a quality initiative., Materials and Methods: A multidisciplinary work group performed a pilot study over 3 months, then implemented various process and work-flow strategies to improve overall door-to-balloon times., Results and Conclusion: We developed a guideline-based, institution-specific written protocol for triaging and managing patients who present to the Emergency Department with symptoms suggestive of STEMI, resulting in shortened median door-to-balloon times from 130.5 to 109.5 minutes (P<0.001).

Ensuring timely access to specialist care is an important indicator of the quality of a health service. Demand for cardiology outpatient appointments has grown considerably in the last decade, leading to increased waiting time for cardiology appointments at public hospitals. This paper examines the effectiveness of past and ongoing strategies initiated by the National Heart Centre, many of which were in collaboration with SingHealth Polyclinics, documents the lessons learnt, and provides a framework for approaching this problem. Instead of a simplistic approach where institutions react to long waiting times by growing capacity to meet demand, this paper emphasises the need to focus on the final intended outcome (timely diagnosis and treatment) rather than on a single performance indicator, such as waiting time. A broad systems approach at the national level is advocated, rather than piecemeal, uncoordinated actions by individual hospitals.

Introduction: Increasing demand for public healthcare and access to specialist care has become a major concern. Characterising the referral pattern to a national centre's cardiology specialist outpatient clinics (SOCs) and the diagnostic outcomes may be useful in formulating referral guidelines to contain rising demand., Materials and Methods: A prospective observational followup study was conducted of all consecutive new patient referrals to the cardiology SOCs of the National Heart Centre over a 1-month period. The records of these 1224 patients were reviewed following their first visit and again after 3 months of evaluation and investigation. Patients' demographics, referral sources, indications of referral, risk factors, provisional and final diagnoses were collected. Referrals from the top 2 volume sources (government polyclinics and hospital Emergency Department) accounted for 600 referrals. These subsidised referrals formed the study group for analysis., Results: The mean age of referred patients was 56 +/- 15.2 years, with equal proportion of males and females. Most patients had known cardiac risk factors of hypertension (53.2%) and hyperlipidaemia (42.3%). Only 23% of referrals had significant cardiac abnormalities. Referrals for typical chest pain derived the highest yield whereas referrals for atypical chest pain, non-cardiac chest pain derived the lowest yield. Referrals for asymptomatic electrocardiogram (ECG) changes (except for atrial flutter/fibrillation) did not yield cardiac abnormalities. Multivariate analysis of chest pain referrals showed typical chest pain and hyperlipidaemia to be statistically significant predictors for coronary artery disease., Conclusion: Referrals to cardiology outpatient specialist clinics should be based on the presence of patient symptoms, particularly that of typical chest pain. In asymptomatic patients, routine ECG screening did not appear to yield significant cardiac abnormalities.

Introduction: The treatment and outcome of acute myocardial infarction (AMI) has evolved greatly over the past few decades. We compared the mortality and complication rates of patients with AMI admitted to the Coronary Care Unit (CCU) in 2002 to previously reported data., Materials and Methods: All data for AMI patients admitted to National Heart Centre CCU in 2002 were collected through the Singapore Cardiac Data Bank, including demographics, in hospital complications and mortality. These were compared to previous reports from the same institution in 1988, 1975 and 1967., Results: A total of 516 cases with AMI were identified. A higher proportion of patients were aged >or=70 years in 2002 (31.8%) compared to 1988 (25%), 1975 (11%) and 1967 (5.6%). Acute percutaneous transluminal coronary angioplasty (PTCA) was performed in 250 of 516 (48%) patients in 2002. The overall in-patient and age-standardised mortality was 14.7% and 10% respectively, compared to 20.6% and 17% respectively in 1988 (P = 0.06). For the 250 patients who underwent acute PTCA, overall mortality was 5.2% compared to 24% in those who did not (P <0.001). Common in-hospital complications included heart failure (38%), non-sustained ventricular tachycardia (8%), atrial fibrillation (8%) and complete heart block (6%). Age, heart failure, bundle branch block and sustained ventricular tachycardia were associated with higher mortality by univariate analysis. On multivariate analysis, older age, heart failure and the absence of percutaneous intervention were independently associated with higher mortality., Conclusion: In-hospital mortality for AMI patients admitted to the CCU declined from 1988 to 2002 despite a higher proportion of elderly patients. The introduction of new therapies including drugs and percutaneous intervention may have contributed to this decline.

This study develops contractility indices in terms of the left ventricular (LV) ellipsoidal geometrical shape-factor. The contractility index (CONT1) is given by the maximum value dsigma(*)/dt wherein sigma(*)=sigma/P, sigma is the wall stress, and sigma(*) is expressed in terms of the shape factor S (the ratio of the minor axis and major axis, B/A, of the instantaneous LV ellipsoidal model). Another contractility index (CONT2) is also developed based on how far apart the in vivo S at the start of ejection is from its optimized value, CONT2=(S(se)-S(se)(op))/S(se)(op), where S(se) refers to the value of S at the start of ejection, S(se)(op) is the derived optimal value of S(se) for which sigma* is maximum. The values of S(=B/A) were calculated from cineventriculographically monitored LV volume, myocardial volume and wall-thickness. Then both the contractility indices were evaluated in normal subjects, as well as in patients with mild heart failure and in patients with severe heart failure. The normal values of CONT1 and CONT2 are 8.75+/-2.30s(-1) and 0.09+/-0.07, respectively. CONT1 decreased in patients with mild and severe heart failures to 5.78+/-1.30 and 3.90+/-1.30, respectively. CONT2 increased in patients with mild and severe heart failures to 0.11+/-0.09 and 0.23+/-0.12, respectively. This implies that a non-optimal and less ellipsoidal shape is associated with decreased contractility (and poor systolic function) of the LV. CONT1 and CONT2 are useful as non-invasively determinable quantitative indices of LV contractility, to distinguish between normal and pathologic LVs.

Background: In this paper, the left ventricle (LV) is modeled as a cylinder with myocardial fibers located helically within its wall. A fiber is modeled into myocardial structural units (MSUs); the core entity of each MSU is the sarcomeric contractile element. The relationship between the sarcomere unit's contractile force and shortening velocity is expressed in terms of the LV model's wall stress and deformation, and hence in terms of the monitored LV pressure and volume. Then, the LV systolic performance is investigated in terms of a mechatronic (excitation-contraction) model of the sarcomere unit located within the LV cylindrical model wall., Methods: The governing equation of dynamics of the LV myocardial structural unit (MSU) is developed, involving the parameters of the series-elastic element (SE), the viscous element (VE) and the contractile element (CE). We then relate the MSU's force and displacement variables (in terms of SE, VE and CE parameters) to the LV pressure and volume, using the patient's catheterization-ventriculogram data. We thereby evaluate the MSU elements' parameters., Results: We then determine the sarcomere (CE) 'force vs. shortening-velocity' characteristics as well as the power generated by the sarcomere (or CE) element. These are deemed to be important LV functional indices. When our computed sarcomeric peak-power is compared against the traditional LV contractility indices (by linear regression), a high degree of correlation is obtained., Conclusions: We have provided herein, a LV systolic-phase (cylindrical geometry) model whose wall contains the myocardial fibers having sarcomere units. We have expressed the LV myocardial sarcomere's CE (force vs. shortening-velocity) characteristics in terms of the LV pressure-volume data. These CE properties express the intrinsic performance capacity of the LV. Hence, indices containing these properties are deemed to reflect LV performance. In this regard, our new LV contractility index correlates very well with the traditional LV contractility index dP/dt(max).