Predictors of Mortality in Acute Myocardial Infarction Complicated by Cardiogenic Shock despite Intra-Aortic Balloon Pump: Opportunities for Advanced Mechanical Circulatory Support in Asia.

Introduction: Acute myocardial infarction complicated by cardiogenic shock (AMI-CS) mortality remains high despite revascularization and the use of the intra-aortic balloon pump (IABP). Advanced mechanical circulatory support (MCS) devices, such as catheter-based ventricular assist devices (cVAD), may impact mortality. We aim to identify predictors of mortality in AMI-CS implanted with IABP and the proportion eligible for advanced MCS in an Asian population. Methods: We retrospectively analyzed a cohort of Society for Cardiovascular Angiography and Intervention (SCAI) stage C and above AMI-CS patients with IABP implanted from 2017-2019. We excluded patients who had IABP implanted for indications other than AMI-CS. Primary outcome was 30-day mortality. Binary logistic regression was used to calculate adjusted odds ratios (aOR) for patient characteristics. Results: Over the 3-year period, 242 patients (mean age 64.1 ± 12.4 years, 88% males) with AMI-CS had IABP implanted. 30-day mortality was 55%. On univariate analysis, cardiac arrest (p < 0.001), inotrope/vasopressor use prior to IABP (p = 0.004) was more common in non-survivors. Non-survivors were less likely to be smokers (p = 0.001), had lower ejection fraction, higher creatinine/ lactate and lower pH (all p < 0.001). On multi-variate analysis, predictors of mortality were cardiac arrest prior to IABP (aOR 4.00, CI 2.28-7.03), inotrope/vasopressor prior to IABP (aOR 2.41, CI 1.18-4.96), lower arterial pH (aOR 0.02, CI 0.00-0.31), higher lactate (aOR 2.42, CI 1.00-1.19), and lower hemoglobin (aOR 0.83, CI 0.71-0.98). Using institutional MCS criteria, 106 patients (44%) would have qualified for advanced MCS. Conclusions: Early mortality in AMI-CS remains high despite IABP. Many patients would have qualified for higher degrees of MCS.

One-year outcomes of patients with ST-segment elevation myocardial infarction during the COVID-19 pandemic.

The pandemic has led to adverse short-term outcomes for patients with ST-segment elevation myocardial infarction (STEMI). It is unknown if this translates to poorer long-term outcomes. In Singapore, the escalation of the outbreak response on February 7, 2020 demanded adaptation of STEMI care to stringent infection control measures. A total of 321 patients presenting with STEMI and undergoing primary percutaneous coronary intervention at a tertiary hospital were enrolled and followed up over 1-year. They were allocated into three groups based on admission date-(1) Before outbreak response (BOR): December 1, 2019-February 6, 2020, (2) During outbreak response (DOR): February 7-March 31, 2020, and (3) control group: November 1-December 31, 2018. The incidence of cardiac-related mortality, cardiac-related readmissions, and recurrent coronary events were examined. Although in-hospital outcomes were worse in BOR and DOR groups compared to the control group, there were no differences in the 1-year cardiac-related mortality (BOR 8.7%, DOR 7.1%, control 4.8%, p = 0.563), cardiac-related readmissions (BOR 15.1%, DOR 11.6%, control 12.0%, p = 0.693), and recurrent coronary events (BOR 3.2%, DOR 1.8%, control 1.2%, p = 0.596). There were higher rates of additional PCI during the index admission in DOR, compared to BOR and control groups (p = 0.027). While patients admitted for STEMI during the pandemic may have poorer in-hospital outcomes, their long-term outcomes remain comparable to the pre-pandemic era.

Characteristics and outcomes of patients with coronary artery ectasia presenting with ST-segment elevation myocardial infarction undergoing primary percutaneous coronary intervention.

BACKGROUND: The clinical significance of coronary artery ectasia (CAE) is not yet fully understood. We aimed to examine differences in clinical and procedural characteristics, clinical management, and outcomes in patients with CAE undergoing primary percutaneous coronary intervention (PPCI) for ST-elevation myocardial infarction (STEMI). METHODS: This was a retrospective analysis of consecutive patients presenting with STEMI with a culprit native coronary artery from July 2015 to June 2019. Patients were divided into CAE and Non-CAE groups as detected on coronary angiography during PPCI. Comparison between groups was made for baseline clinical and procedural characteristics, as well as complications, pharmacological treatment, and follow-up outcomes. RESULTS: 36/1780 (2.0%) patients were found to have CAE. Patients with CAE had a median age of 57.1 ± 11.7 years and were more likely to be male 33/36 (91.7%). Diabetes was less commonly seen in the CAE group (11.1% vs 31.4%, p = 0.010), and there were no differences in the proportion of patients with hypertension and hyperlipidemia. Patients with CAE had more involvement of right coronary artery (RCA) culprit vessel (63.9% vs. 38.4%, p = 0.026), less coronary stenting (25.0% vs 87.2%, p < 0.001) and post-PPCI TIMI 3 flow (69.4% vs 95.5%, P < 0.001), and were more likely to be discharged with oral anticoagulants (36.1% vs 7.6%, p < 0.001). At 3-year follow-up, all-cause mortality rates were higher in the non-CAE group (0.0% vs 11.5%, p < 0.028), suggesting that CAE was not associated with unfavorable long-term outcome. On multivariate analysis, CAE was not an independent predictor of MACE. CONCLUSION: Despite lower rates of post-PPCI TIMI 3 flow, CAE was not associated with unfavorable long-term outcome.

Characteristics and outcomes of young patients with ST segment elevation myocardial infarction undergoing primary percutaneous coronary intervention: retrospective analysis in a multiethnic Asian population.

OBJECTIVE: ST segment elevation myocardial infarction (STEMI) is associated with significant mortality leading to loss of productive life years, especially in younger patients. This study aims to compare the characteristics and outcomes of young versus older patients with STEMI undergoing primary percutaneous coronary intervention (PPCI) to help focus public health efforts in STEMI prevention. METHODS: Data from the Coronary Care Unit database of the National University Hospital, Singapore from July 2015 to June 2019 were reviewed. Patients were divided into young (<50 years old) or older (≥50 years old) groups. RESULTS: Of the 1818 consecutive patients with STEMI who underwent PPCI, 465 (25.6%) were <50 years old. Young compared with older patients were more likely to be male, current smokers, of Indian ethnicity, have family history of ischaemic heart disease (IHD) and had lower 1 year mortality (3.4% vs 10.4%, p<0.0001). Although diabetes, hypertension or dyslipidaemia was less common among young patients, the prevalence of having any one of these risk factors was high in the range of 28% to 38%. Age was an independent predictor of mortality in the older but not younger patients with STEMI, and diabetes showed a trend towards mortality in both groups. CONCLUSION: Young patients with STEMI are more often smokers, of Indian ethnicity and had family history of IHD, although cardiometabolic risk factors are also prevalent. Mortality is lower, but not negligible, among the young patients with STEMI. Public health efforts are needed to reduce the prevalence of these risk factors among the constitutionally susceptible population.

Impact of the COVID-19 Pandemic on Door-to-Balloon Time for Primary Percutaneous Coronary Intervention　- Results From the Singapore Western STEMI Network.

BACKGROUND: Little is known about the effect of the coronavirus disease 2019 (COVID-19) pandemic and the outbreak response measures on door-to-balloon time (D2B). This study examined both D2B and clinical outcomes of patients with STEMI undergoing primary percutaneous coronary intervention (PPCI).Methods and Results:This was a retrospective study of 303 STEMI patients who presented directly or were transferred to a tertiary hospital in Singapore for PPCI from October 2019 to March 2020. We compared the clinical outcomes of patients admitted before (BOR) and during (DOR) the COVID-19 outbreak response. The study outcomes were in-hospital death, D2B, cardiogenic shock and 30-day readmission. For direct presentations, fewer patients in the DOR group achieved D2B time <90 min compared with the BOR group (71.4% vs. 80.9%, P=0.042). This was more apparent after exclusion of non-system delay cases (DOR 81.6% vs. BOR 95.9%, P=0.006). Prevalence of both out-of-hospital cardiac arrest (9.5% vs. 1.9%, P=0.003) and acute mitral regurgitation (31.6% vs. 17.5%, P=0.006) was higher in the DOR group. Mortality was similar between groups. Multivariable regression showed that longer D2B time was an independent predictor of death (odds ratio 1.005, 95% confidence interval 1.000-1.011, P=0.029). CONCLUSIONS: The COVID-19 pandemic and the outbreak response have had an adverse effect on PPCI service efficiency. The study reinforces the need to focus efforts on shortening D2B time, while maintaining infection control measures.