Optimal door-to-balloon time for primary percutaneous coronary intervention for ST-elevation myocardial infarction.

BACKGROUND: Door-to-balloon time (DTBT) for ST-elevation myocardial infarction (STEMI) is a performance metric by which primary percutaneous coronary intervention (PPCI) services are assessed. METHODS: Consecutive patients presenting with STEMI undergoing PPCI between January 2007 to December 2019 from the Singapore Myocardial Infarction Registry were included. Patients were stratified based on DTBT (≤60 min, 61-90 min, 91-180 min) and Killip status (I-III vs. IV). Outcomes assessed included all-cause mortality and major adverse cardiovascular events (MACE) at 30-days and 1-year. RESULTS: In total, 13,823 patients were included, with 82.59% achieving DTBT ≤90 min and 49.77% achieving DTBT ≤60 min. For Killip I-III (n = 11,591,83.85%), the median DTBT was 60[46-78]min. The 30-day all-cause mortality for DTBT of ≤60 min, 61-90 min and 91-180 min was 1.08%, 2.17% and 4.33% respectively (p < 0.001). On multivariate analysis, however, there was no significant difference for 30-day and 1-year outcomes across all DTBT (p > 0.05). For Killip IV, the median DTBT was 68[51-91]min. The 30-day all-cause mortality for DTBT of ≤60 min, 61-90 min and 91-180 min was 11.74%, 20.48% and 35.06% respectively (p < 0.001). On multivariate analysis for 30-day and 1-year outcomes, DTBT 91-180 min was an independent predictor of worse outcomes (p < 0.05), but there was no significant difference between DTBT of ≤60 min and 61-90 min (p > 0.05). CONCLUSION: In Killip I-III patients, DTBT had no significant impact on outcomes upon adjustment for confounders. Conversely, for Killip IV patients, a DTBT of >90 min was associated with significantly higher adverse outcomes, with no differences between a DTBT of ≤60 min vs. 61-90 min. Outcomes in STEMI involve a complex interplay of factors and recommendations of a lowered DTBT of ≤60 min will require further evaluation.

Impact of COVID-19 pandemic early response measures on myocardial infarctions and acute cardiac care in Singapore.

The COVID -19 pandemic impacted acute myocardial infarction (AMI) attendances, ST-elevation myocardial infarction (STEMI) treatments, 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'. We collected aggregate numbers of weekly elective PCI from four centres and AMI admissions, PPCI, and in-hospital mortality from five centres. Exact door-to-balloon (DTB) times were recorded for one centre; another two reported proportions of DTB times exceeding targets. 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 non-STEMI (NSTEMI) admissions decreased significantly from 'Before DORSCON Orange' to 'DORSCON Orange to start of CB' (59 vs 48, P = 0.005) and were sustained during CB (39 cases). Exact DTB times reported by one centre showed no significant change in the median. Out of three centres, two reported significant increases in the proportion that exceeded DTB targets. In-hospital mortality rates remained static. In Singapore, STEMI and PPCI rates remained stable, while NSTEMI rates decreased during DORSCON Orange and CB. The severe acute respiratory syndrome (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.

Direct Oral Anticoagulation Versus Warfarin in Left Ventricular Thrombus: Pooled Analysis of Randomized Controlled Trials.

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.

Clinical outcomes in end stage renal disease on dialysis and severe coronary artery disease: A real-world study.

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.

Pericarditis and myocarditis after COVID-19 mRNA vaccination in a nationwide setting.

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.

Coronary Intravascular Lithotripsy Versus Rotational Atherectomy in an Asian Population: Clinical Outcomes in Real-World Patients.

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.

Early Coronary Angiography Is Associated with Improved 30-Day Outcomes among Patients with Out-of-Hospital Cardiac Arrest.

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.

Age and diabetes mellitus associated with worse outcomes after percutaneous coronary intervention in a multi-ethnic Asian dialysis patient population.

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.

Building a Longitudinal National Integrated Cardiovascular Database　- Lessons Learnt From SingCLOUD.

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".

First Medical Contact-to-Device Time and Heart Failure Outcomes Among Patients Undergoing Primary Percutaneous Coronary Intervention.

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 admission increased from 12.2% in 2007 to 18.4% in 2013, P=0.020, whereas postadmission in-hospital HF decreased from 12.8% in 2007 to 7.1% in 2013, P=0.030. HF rehospitalization increased from 1.2% in 2007 to 2.6% in 2013 ( P=0.003), for 30-day HF rehospitalization, and 3.8% in 2007 to 5.6% in 2013 ( P=0.037), for 1-year HF rehospitalization. At the individual level, among patients with HF at admission (N=1191), longer FTD time was associated with more 30-day HF rehospitalization (compared with ≤60 minutes, adjusted hazard ratio, 1.68 [0.73-3.86] for 60-90 minutes, 2.88 [1.19-6.92], for 90-120 minutes, and 2.84 [1.08-7.44] for >120 minutes). Longer FTD time was associated with a greater risk of postadmission in-hospital HF (compared with ≤60 minutes, adjusted hazard ratio, 1.18 [0.96-1.44] for 60-90 minutes, 1.59 [1.25-2.03] for 90-120 minutes, and 1.67 [1.26-2.21] for >120 minutes). Conclusions: Temporal reductions in FTD time were associated with decrease in postadmission in-hospital HF. Among patients presenting with HF at admission, delays in FTD beyond 90 minutes were associated with more 30-day HF rehospitalization.

Impact of aortic root size on left ventricular afterload and stroke volume.

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.

Myocardial contractile dysfunction associated with increased 3-month and 1-year mortality in hospitalized patients with heart failure and preserved ejection fraction.

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.