The Prognostic Yield of Admission Shock Index in Patients with ST-Segment Elevation Myocardial Infarction: SEMI-CI Study

Background

Early identification of high-risk patients presenting with ST-segment elevation myocardial infarction (STEMI) helps prevent complications. The shock index (SI) is a bedside risk-stratification tool used in emergency departments. In this study, we aimed to assess the SI's predictive value for prognosticating in-hospital and one-year mortality, as well as one-year major cardiovascular events (MACEs). As secondary endpoints, we assessed the age SI's performance and the influence of prehospital transport factors on SI's predictive value.

Methods

This prospective cohort study is named SEMI-CI and enrolled patients with STEMI who were referred to a cardiology hospital in Isfahan. We analyzed data on 867 patients with STEMI. Systolic blood pressure (SBP) and heart rate (HR) upon admission were used to calculate SI. Patients were divided into two groups based on SI, and 277 patients had SI > 0.7.

Results

In-hospital death, one-year mortality, and MACE were more prevalent in those patients presenting with SI ≥ 0.7. However, after multivariate adjustment, SI was an independent predictor of in-hospital mortality and MACE, but it was not associated with one-year mortality. Furthermore, mortality rates increased from lower to higher age groups. Among patients transferred by emergency medical services to our hospital, SI showed prognostic implications for in-hospital mortality but not for one-year mortality.

Conclusions

The current study showed that a positive SI and age SI are valuable risk-stratification tools to identify high-risk patients presenting with STEMI.

Association of Shock Index with Echocardiographic Parameters in Cardiac Intensive Care Unit

BACKGROUND

A high shock index (SI), the ratio of heart rate (HR) to systolic blood pressure (SBP), has been associated with unfavorable outcomes. We sought to determine the hemodynamic underpinnings of an elevated SI using 2-D and doppler Transthoracic Echocardiography (TTE) in unselected cardiac intensive care unit (CICU) patients.

METHODS

We included Mayo Clinic CICU admissions from 2007 to 2018 who were in sinus rhythm at the time of TTE. The SI was calculated using HR and SBP at the time of TTE. Patients were grouped according to SI: <0.7, 4012 (64%); 0.7-0.99, 1764 (28%); and ≥ 1.0, 513 (8%). Pearson's correlation coefficient was used to assess associations between continuous variables.

RESULTS

We included 6289 unique CICU patients, 58% of whom had acute coronary syndrome. The median age was 67.9 years old and 37.8% were females. The mean SI was 0.67 BPM/mmHg. As the SI increased, markers of left ventricular (LV) systolic function and forward flow decreased, including left ventricular ejection fraction (LVEF), fractional shortening, left ventricular outflow tract (LVOT) velocity time integral (VTI), stroke volume, LV stroke work index, and cardiac power output. Biventricular filling pressures increased, and markers of right ventricular function worsened with rising SI. Most TTE measurements reflecting LV function and forward flow were inversely correlated with SI, including LV stroke work index (r = -0.59) and LVOT VTI (r = -0.41), as were both systemic vascular resistance index (r = -0.43) and LVEF (r = -0.23).

CONCLUSION

CICU patients with elevated SI have worse biventricular function and systemic hemodynamics, particularly decreased stroke volume and related calculated TTE parameters. The SI is an easily available marker that can be used to identify CICU patients with unfavorable hemodynamics who may require further assessment.

Predictors of Mortality for Patients with ST-Elevation Myocardial Infraction after 2-Year Follow-Up: A ST-Elevation Myocardial Infarction Cohort in Isfahan Study

Background

Mortality of ST-elevation myocardial infarction (STEMI) patients is increasing in world. This study defines predictors of mortality in patients who have STEMI.

Materials and Methods

This study was a part of the ST-elevated myocardial infarction cohort study in Isfahan conducted on 876 acute myocardial infarction (MI) followed for 2 years that 781 patient entered. The effect of predictors of mortality includes demographic, physiological, and clinical characterizes compared in two groups alive and died patients. MACE was defined as nonfatal MI, nonfatal stroke, and atherosclerosis cardiovascular disease-related death was recorded. Univariate and multiple logistic regression analyses were performed. All analyses performed using SPSS 20.0. P < 0.05 considered statistically significant.

Results

A total 781 patients, 117 (13%) that 72 (8.5%) was in-hospital died. The mean (standard deviation) age of the patients was 60.92 (12.77) years and 705 (81.3%) patients were males. Significant factors that affected mortality on analysis of demographic and physiological parameters were age (P < 0.001), sex (P = 0.004), transfusion (P = 0.010), STEMI type (P < 0.001), number epicardial territories >50% (P = 0.001), ventilation options (P < 0.001), smoker (P = 0.003), and diabetes (P = 0.026). Significant clinical factors affected mortality were ejection fraction (EF) (P < 0.001), creatinine (P < 0.001), hemoglobin (P < 0.001), low-density lipoprotein-cholesterol (LDL-C) (P = 0.019), and systolic blood pressure (P < 0.001). Multiple logistics regression model definition significant predictors for mortality were age (P < 0.001), heart rate (HR) (P = 0.007), EF (0.039), LDL-C (P = 0.002), and preangia (P = 0.022).

Conclusion

The set of factors can increase or decrease mortality in these patients. Significant predictors of mortality STEMI patients by 2-year follow up were age, HR, EF, LDL-C, and preangia. It seems that more articles need to be done in different parts of Iran to confirm the results.

Shock index and modified shock index are predictors of long-term mortality not only in STEMI but also in NSTEMI patients

BACKGROUND

Shock index (SI) and modified shock index (mSI) are useful instruments for early risk stratification in acute myocardial infarction (AMI) patients. They are strong predictors for short-term mortality. Nevertheless, the association between SI or mSI and long-term mortality in AMI patients has not yet been sufficiently examined.

MATERIAL AND METHODS

For this study, a total of 10,174 patients with AMI was included. All cases were prospectively recorded by the population-based Augsburg Myocardial Infarction Registry from 2000 until 2017. Endpoint was all-cause mortality with a median observational time of 6.5 years [IQR: 3.5-7.4]. Using ROC analysis and calculating Youden-Index, the sample was dichotomized into a low and a high SI and mSI group, respectively. Moreover, multivariable adjusted COX regression models were calculated. All analyses were performed for the total sample as well as for STEMI and NSTEMI cases separately.

RESULTS

Optimal cut-off values were 0.580 for SI and 0.852 for mSI (total sample). AUC values were 0.6382 (95% CI: 0.6223-0.6549) for SI and 0.6552 (95% CI: 0.6397-0.6713) for mSI. Fully adjusted COX regression models revealed significantly higher long-term mortality for patients with high SI and high mSI compared to patients with low indices (high SI HR: 1.42 [1.32-1.52], high mSI HR: 1.46 [1.36-1.57]). Furthermore, the predictive ability was slightly better for mSI compared to SI and more reliable in NSTEMI cases compared to STEMI cases (for SI and mSI).

CONCLUSION

High SI and mSI are useful tools for early risk stratification including long-term outcome especially in NSTEMI cases, which can help physicians to make decision on therapy. NSTEMI patients with high SI and mSI might especially benefit from immediate invasive therapy.Key messagesShock index and modified shock index are predictors of long-term mortality after acute myocardial infarction.Both indices predict long-term mortality not only for STEMI cases, but even more so for NSTEMI cases.

Prognostic value of shock index in patients admitted with non-ST-segment elevation myocardial infarction: the ARIC study community surveillance

AIMS

Shock index (SI), defined as the ratio of heart rate (HR) to systolic blood pressure (SBP), is easily obtained and predictive of mortality in patients with ST-segment elevation myocardial infarction. However, large-scale evaluations of SI in patients with non-ST-segment elevation myocardial infarction (NSTEMI) are lacking.

METHODS AND RESULTS

Hospitalizations for acute myocardial infarction were sampled from four US areas by the Atherosclerosis Risk in Communities (ARIC) study and classified by physician review. Shock index was derived from the HR and SBP at first presentation and considered high when ≥0.7. From 2000 to 2014, 18 301 weighted hospitalizations for NSTEMI were sampled and had vitals successfully obtained. Of these, 5753 (31%) had high SI (≥0.7). Patients with high SI were more often female (46% vs. 39%) and had more prevalent chronic kidney disease (40% vs. 32%). TIMI (Thrombolysis in Myocardial Infarction) risk scores were similar between the groups (4.3 vs. 4.2), but GRACE (Global Registry of Acute Coronary Syndrome) score was higher with high SI (140 vs. 118). Angiography, revascularization, and guideline-directed medications were less often administered to patients with high SI, and the 28-day mortality was higher (13% vs. 5%). Prediction of 28-day mortality by SI as a continuous measurement [area under the curve (AUC): 0.68] was intermediate to that of the GRACE score (AUC: 0.87) and the TIMI score (AUC: 0.54). After adjustments, patients with high SI had twice the odds of 28-day mortality (odds ratio = 2.02; 95% confidence interval: 1.46-2.80).

CONCLUSION

The SI is easily obtainable, performs moderately well as a predictor of short-term mortality in patients hospitalized with NSTEMI, and may be useful for risk stratification in emergency settings.

Nomogram for the Prediction of Intrahospital Mortality Risk of Patients with ST-Segment Elevation Myocardial Infarction Complicated with Hyperuricemia: A Multicenter Retrospective Study

Purpose

This study aimed to establish an accurate and easy predictive model for ST-segment elevation myocardial infarction (STEMI) patients with hyperuricemia, using readily available features to estimate intrahospital mortality risk.

Patients and Methods

This was a multicenter retrospective study involving the development of risk prediction models for intrahospital mortality among all STEMI patients with hyperuricemia from Zunyi Medical University Chest Pain Center’s specialized alliance between January 1, 2016 and June 30, 2020. The primary outcome was intrahospital mortality. A total of 48 candidate variables were considered from demographic and clinical data. The least absolute shrinkage and selection operator (LASSO) was used to develop a nomogram. Concordance index values, decision curve analysis, the area under the curve (AUC), and clinical impact curves were examined. In this study, 489 patients with STEMI were included in the training dataset and an additional 209 patients from the 44 chest pain centers were included in the test cohort. B-type natriuretic peptides, α-hydroxybutyrate dehydrogenase (α-HBDH), cystatin C, out-of-hospital cardiac arrest (OHCA), shock index, and neutrophil-to-lymphocyte ratio were associated with intrahospital mortality and included in the nomogram.

Results

The model showed good discrimination power, and the AUC generated to predict survival in the training set was 0.875 (95% confidence interval, 0.825–0.925). In the validation set, the AUC of survival predictions was 0.87 (95% confidence interval, 0.792–0.947). Calibration plots and decision curve analysis showed good model performance in both datasets. A web-based calculator (https://bzxzmu.shinyapps.io/STEMI-with-Hyperuricemia-intrahospital-mortality/) was established based on the nomogram model, which was used to measure the levels of OHCA, neutrophil-to-lymphocyte ratio, shock index, α-HBDH, cystatin C, and B-type natriuretic peptides.

Conclusion

For practical applications, this model may prove clinically useful for personalized therapy management in patients with STEMI with hyperuricemia.

Development of a machine learning model to predict the risk of late cardiogenic shock in patients with ST-segment elevation myocardial infarction

Background

The in-hospital mortality of patients with ST-segment elevation myocardial infarction (STEMI) increases to more than 50% following a cardiogenic shock (CS) event. This study highlights the need to consider the risk of delayed calculation in developing in-hospital CS risk models. This report compared the performances of multiple machine learning models and established a late-CS risk nomogram for STEMI patients.

Methods

This study used logistic regression (LR) models, least absolute shrinkage and selection operator (LASSO), support vector regression (SVM), and tree-based ensemble machine learning models [light gradient boosting machine (LightGBM) and extreme gradient boosting (XGBoost)] to predict CS risk in STEMI patients. The models were developed based on 1,598 and 684 STEMI patients in the training and test datasets, respectively. The models were compared based on accuracy, the area under the curve (AUC), recall, precision, and Gini score, and the optimal model was used to develop a late CS risk nomogram. Discrimination, calibration, and the clinical usefulness of the predictive model were assessed using C-index, calibration plotd, and decision curve analyses.

Results

A total of 2282 STEMI patients recruited between January 1, 2016 and May 31, 2020, were included in the complete dataset. The linear models built using LASSO and LR showed the highest overall predictive power, with an average accuracy over 0.93 and an AUC above 0.82. With a C-index of 0.811 [95% confidence interval (CI): 0.769-0.853], the LASSO nomogram showed good differentiation and proper calibration. In internal validation tests, a high C-index value of 0.821 was achieved. Decision curve analysis (DCA) and clinical impact curve (CIC) examination showed that compared with the previous score-based models, the LASSO model showed superior clinical relevance.

Conclusions

In this study, five machine learning methods were developed for in-hospital CS prediction. The LASSO model showed the best predictive performance. This nomogram could provide an accurate prognostic prediction for CS risk in patients with STEMI.

ST-Segment Elevation Acute Myocardial Infarction Complicated by Cardiogenic Shock: Early Predictors of Very Long-Term Mortality

BACKGROUND

Cardiogenic shock (CS) is the leading cause of in-hospital mortality in ST-segment elevation myocardial infarction (STEMI). Only limited data are available on the long-term outcome of STEMI patients with CS undergoing contemporary treatment. We aimed to investigate long-term mortality and its predictors in STEMI patients with CS and to develop a risk score for long-term mortality prediction.

METHODS AND RESULTS

We retrospectively included 465 patients with STEMI complicated by CS and treated with primary angioplasty and intra-aortic balloon pump between 2005 and 2018. Long-term mortality, including both in-hospital mortality and all-cause mortality following discharge from the index hospitalization, was the primary endpoint. The long-term mortality (median follow-up 4 (2.0-5.2) years) was 60%, including in-hospital mortality (34%). At multivariate analysis, independent predictors of long-term mortality were age (HR 1.41, each 10-year increase), admission left ventricular ejection fraction (HR 1.51, each 10%-unit decrease) and creatinine (HR 1.28, each mg/dl increase), and acute kidney injury (HR 1.81). When these predictors were pooled together, the area under the curve (AUC) for long-term mortality was 0.80 (95% CI 0.75-0.84). Using the four variables, we developed a risk score with a mean (cross-validation analysis) AUC of 0.79. When the score was applied to in-hospital mortality, its AUC was 0.79, and 0.76 when the score was applied to all-cause mortality following discharge.

CONCLUSIONS

In STEMI patients with CS, the risk of death is still substantial in the years following the index event. A simple clinical score at the time of the index event accurately predicts long-term mortality risk.

Comparison of shock index-based risk indices for predicting in-hospital outcomes in patients with ST-segment elevation myocardial infarction undergoing percutaneous coronary intervention

Objective

We aimed to determine whether the prognostic value of the shock index (SI) and its derivatives is better than that of the Thrombolysis In Myocardial Infarction risk index (TRI) for predicting adverse outcomes in patients with ST-segment elevation myocardial infarction (STEMI) undergoing primary percutaneous coronary intervention (PCI).

Methods

A total of 257 patients with STEMI undergoing primary PCI from January 2018 to June 2019 were analyzed in a retrospective cohort study. The SI, modified shock index (MSI), age SI (age × the SI), age MSI (age × the MSI), and TRI at admission were calculated. Clinical endpoints were in-hospital complications, including all-cause mortality, acute heart failure, cardiac shock, mechanical complications, re-infarction, and life-threatening arrhythmia.

Results

Multivariate analyses showed that a high SI, MSI, age SI, age MSI, and TRI at admission were associated with a significantly higher rate of in-hospital complications. The predictive value of the age SI and age MSI was comparable with that of the TRI (area under the receiver operating characteristic curve: z = 1.313 and z = 0.882, respectively) for predicting in-hospital complications.

Conclusions

The age SI and age MSI appear to be similar to the TRI for predicting in-hospital complications in patients with STEMI undergoing primary PCI.

Peri-Procedural Blood Pressure Changes and Their Relationship with MACE in Patients Undergoing Percutaneous Coronary Intervention: A Cross-Sectional Study

Background

Peri-procedural blood-pressure (BP) changes were investigated and correlated to Major adverse cardiovascular events (MACE) as predictor of outcome for patients undergoing percutaneous coronary intervention (PCI); whether acute coronary syndrome (Unstable angina, or MI; STEMI or NSTEMI) or scheduled for elective PCI.

Methods

Resting BP in the 204 recruited patients undergoing PCI throughout 2018 was measured thrice – in the ward before transferring to the cardiac catheterization lab (cath lab), in the cath lab, and after transfer to the recovery room. Patients were categorized based on their systolic and diastolic BP peri-procedural difference as systolic (SBP): with a large difference (>20 mmHg, n=47), with a small difference (≤20 mmHg, n=157) (shock patients excluded); diastolic (DBP): with a large difference (>10 mmHg, n=65), and with a small difference (≤10 mmHg, n=139). The primary end-points were MACE including all-cause mortality, non-fatal myocardial infarction, and stroke during the hospital stay. The Mann–Whitney U and Chi-square tests were used to analyze the data accordingly (p<0.005).

Results

Within the category of MACE, cardiac mortality was the only adverse cardiac event encountered in the study sample. Cardiac mortality was significantly higher in both the large SBP-difference group versus the other group (10.6% vs 0.6%, p=0.003) and the large DBP-difference group versus the small-difference group (7.7% vs 0.7%, p=0.013).

Conclusion

Peri-procedural systolic and diastolic BP differences, greater than 20 mmHg and 10 mmHg, respectively, correlated with MACE in all patients undergoing PCI.

Effects of chronic beta-blocker treatment on admission haemodynamics in STEMI patients treated with primary angioplasty

Background:

The association between chronic beta-blocker treatment and haemodynamics at admission in patients with ST-segment elevation myocardial infarction treated by primary percutaneous coronary intervention is not well studied. We investigated the impact of chronic beta-blocker treatment on the risk of cardiogenic shock and pre-shock at admission in patients with ST-segment elevation myocardial infarction treated by primary percutaneous coronary intervention.

Methods and results:

A total of 4907 patients with ST-segment elevation myocardial infarction treated with primary percutaneous coronary intervention were included in the study. A total of 1148 patients (23.3%) were on chronic beta-blocker treatment. Cardiogenic shock was observed in 264 patients (5.3%). Pre-shock was defined as a shock index (the ratio of heart rate and systolic blood pressure) of 0.7 or greater, and was observed in 1022 patients (20.8%). The risk of cardiogenic shock in patients with chronic beta-blocker treatment was not increased (adjusted hazard ratio (HR) 0.97, 95% confidence interval (CI) 0.65–1.46, P=0.90). Chronic beta-blocker treatment was also not associated with an increased risk of pre-shock (adjusted HR 0.86, 95% CI 0.68–1.07, P=0.19). Also after propensity score matched analysis, there was no increased risk of cardiogenic shock or pre-shock in patients with chronic beta-blocker treatment (respectively HR 0.97, 95% CI 0.61–1.51, P=0.88 and HR 0.82, 95% CI 0.65–1.06, P=0.12).

Conclusion:

In ST-segment elevation myocardial infarction, chronic beta-blocker treatment is not associated with an increased risk of cardiogenic shock or pre-shock.

Prognostic Impact of Active Mechanical Circulatory Support in Cardiogenic Shock Complicating Acute Myocardial Infarction, Results from the Culprit-Shock Trial

OBJECTIVES

To analyze the use and prognostic impact of active mechanical circulatory support (MCS) devices in a large prospective contemporary cohort of patients with cardiogenic shock (CS) complicating acute myocardial infarction (AMI).

BACKGROUND

Although increasingly used in clinical practice, data on the efficacy and safety of active MCS devices in patients with CS complicating AMI are limited.

METHODS

This is a predefined subanalysis of the CULPRIT-SHOCK randomized trial and prospective registry. Patients with CS, AMI and multivessel coronary artery disease were categorized in two groups: (1) use of at least one active MCS device vs. (2) no active MCS or use of intra-aortic balloon pump (IABP) only. The primary endpoint was a composite of all-cause death or renal replacement therapy at 30 days.

RESULTS

Two hundred of 1055 (19%) patients received at least one active MCS device (n = 112 Impella^®; n = 95 extracorporeal membrane oxygenation (ECMO); n = 6 other devices). The primary endpoint occurred significantly more often in patients treated with active MCS devices compared with those without active MCS devices (142 of 197, 72% vs. 374 of 827, 45%; p < 0.001). All-cause mortality and bleeding rates were significantly higher in the active MCS group (all p < 0.001). After multivariable adjustment, the use of active MCS was significantly associated with the primary endpoint (odds ratio (OR) 4.0, 95% confidence interval (CI) 2.7-5.9; p < 0.001).

CONCLUSIONS

In the CULPRIT-SHOCK trial, active MCS devices were used in approximately one fifth of patients. Patients treated with active MCS devices showed worse outcome at 30 days and 1 year.

Shock index and TIMI risk index as valuable prognostic tools in patients with acute coronary syndrome complicated by cardiogenic shock

Background

The aim of the study was to evaluate the usefulness of the shock index (SI) and the TIMI risk index (TRI Thrombolysis in Myocardial Infarction Risk Index) one hour after successful primary percutaneous coronary intervention (pPCI) for predicting in-hospital mortality in patients with acute coronary syndrome complicated by cardiogenic shock (CS).

Methods

Forty-seven consecutive patients with acute myocardial infarction (AMI) complicated by CS were included in this prospective observational study. All patients underwent pPCI and obtained TIMI Grade Flow 3. SI and TRI were calculated one hour after pPCI.

Results

The primary endpoint—death from cardiovascular causes—occurred in 17 patients (36%). All calculated parameters were significantly higher in fatal CS than in the non-fatal CS group. A multivariate logistic regression model found only TRI to be an independent, significant predictor of death in the study group, with a proposed cut-off point of 66, with sensitivity 76.5% and specificity 83.3% (AUC 0.811, p = 0.00001).

Conclusions

The simple parameters of clinical assessment—SI and TRI—calculated one hour after a successful pPCI of infarct related artery are important predictors of death in AMI complicated by cardiogenic shock.

Utility of shock index in 24,636 patients presenting with acute coronary syndrome

BACKGROUND

Shock index is a bedside reflection of integrated response of the cardiovascular and nervous systems. We aimed to evaluate the utility of shock index (heart rate/systolic blood pressure) in patients presenting with acute coronary syndrome (ACS).

METHODS

We analyzed pooled data from seven Arabian Gulf registries; these ACS registries were carried out in seven countries (Qatar, Bahrain, Kuwait, UAE, Saudi Arabia, Oman and Yemen) between 2005 and 2017. A standard uniform coding strategy was used to recode each database using each registry protocol and clinical research form. Patients were categorized into two groups based on their initial shock index (low vs. high shock index). Optimal shock index cutoff was determined according to the receiver operating characteristic curve (ROC). Primary outcome was hospital mortality.

RESULTS

A total of 24,636 ACS patients met the inclusion criteria with a mean age 57±13 years. Based on ROC analysis, the optimal shock index was 0.80 (83.5% had shock index <0.80 and 16.5% had shock index ≥0.80). In patients with high shock index, 55% had ST-elevation myocardial infarction and 45% had non-ST-elevation myocardial infarction. Patients with high shock index were more likely to have diabetes mellitus, late presentation, door to electrocardiogram >10 min, symptom to Emergency Department > 3 h, anterior myocardial infarction, impaired left ventricular function, no reperfusion post-therapy, recurrent ischemia/myocardial infarction, tachyarrhythmia and stroke. However, high shock index was associated significantly with less chest pain, less thrombolytic therapy and less primary percutaneous coronary intervention. Shock index correlated significantly with pulse pressure (r= -0.52), mean arterial pressure (r= -0.48), Global Registry of Acute Coronary Events score (r =0.41) and Thrombolysis In Myocardial Infarction simple risk index (r= -0.59). Shock index ≥0.80 predicted mortality in ACS with 49% sensitivity, 85% specificity, 97.6% negative predictive value and 0.6 negative likelihood ratio. Multivariate regression analysis showed that shock index was an independent predictor for in-hospital mortality (adjusted odds ratio (aOR) 3.40, p<0.001), heart failure (aOR 1.67, p<0.001) and cardiogenic shock (aOR 3.70, p<0.001).

CONCLUSIONS

Although shock index is the least accurate of the ones tested, its simplicity may argue in favor of its use for early risk stratification in patients with ACS. The utility of shock index is equally good for ST-elevation myocardial infarction and non-ST-elevation acute coronary syndrome. High shock index identifies patients at increased risk of in-hospital mortality and urges physicians in the Emergency Department to use aggressive management.

Association of shock index with short-term and long-term prognosis after ST-segment elevation myocardial infarction

BACKGROUND

The association of shock index with long-term mortality after ST-segment elevation myocardial infarction (STEMI) remains poorly investigated. We aimed to assess the association between shock index and eight-year mortality after STEMI.

METHODS

The study included 1369 patients with STEMI undergoing primary percutaneous coronary intervention (PPCI). Patients were categorized into three groups: a group with shock index in the first tertile (shock index, 0.21 to 0.52; n = 458), a group with shock index in the second tertile (shock index > 0.52 to 0.67; n = 457) and a group with shock index in the third tertile (shock index > 0.67 to 2.80; n = 454). The primary outcome was eight-year mortality.

RESULTS

In patients with shock index in the first to third tertiles, inhospital cardiogenic shock (n = 153) occurred in 3.5, 3.9 and 26.2% of patients, respectively [adjusted odds ratio = 1.54, 95% confidence interval (CI) 1.40 to 1.69, P < 0.001]; 30-day deaths (n = 122) occurred in 2.8, 5.5 and 18.5% of patients, respectively [adjusted hazard ratio = 1.06 (1.01-1.12); P = 0.024]; eight-year deaths (n = 300) occurred in 22.9, 21.6 and 36.1% of patients, respectively [adjusted hazard ratio = 1.06 (1.02-1.11); P = 0.007] with all risk estimates calculated per 0.1 unit increment in shock index values. From 30 days to 8 years, deaths (n = 178) occurred in 20.7, 17.0 and 21.5% of patients in the first to third shock index tertiles, respectively (the difference was nonsignificant for all intertertile comparisons).

CONCLUSIONS

In patients with STEMI, elevated shock index is associated with the risk of inhospital cardiogenic shock and mortality up to 8 years after PPCI. The long-term adverse prognosis was almost entirely driven by events within the first 30 days.

Age shock index and age-modified shock index are strong predictors of outcomes in ST-segment elevation myocardial infarction patients undergoing emergency percutaneous coronary intervention

BACKGROUND

Early identification of high-risk patients provides clinicians with greater decision-making time and better informs strategies to cope with disease. The predictive values of age shock index (age SI) and age-modified shock index (age MSI) in ST-segment elevation myocardial infarction (STEMI) patients undergoing emergency percutaneous coronary intervention (PCI) have rarely been reported, especially compared with those for SI, MSI, and the Global Registry of Acute Coronary Events (GRACE) risk score.

PATIENTS AND METHODS

Nine hundred and eighty-three STEMI patients undergoing emergency PCI between January 2014 and September 2017 were analyzed in a retrospective cohort study. The primary outcomes were rates of in-hospital cardiovascular events, and 6-month and long-term all-cause mortality.

RESULTS

In multivariate analyses, the predictive values of age SI and age MSI were comparable to that of the GRACE score, but superior to those of SI and MSI for in-hospital cardiac mortality [age SI: odds ratio (OR) = 1.05, P < 0.001, area under the receiver operating characteristic (ROC-AUC) = 0.805, P < 0.001; age MSI: OR = 1.04, P < 0.001, ROC-AUC = 0.813, P < 0.001; GRACE score: OR = 1.03, P < 0.001, ROC-AUC = 0.827, P < 0.001], 6-month all-cause mortality (age SI: OR = 1.04, P < 0.001, ROC-AUC = 0.791, P < 0.001; age MSI: OR = 1.03, P < 0.001, ROC-AUC = 0.801, P < 0.001; GRACE score: ROC-AUC = 0.828, P < 0.001), long-term all-cause mortality [age SI: hazard ratio (HR) = 1.06, P < 0.001, ROC-AUC = 0.798, P < 0.001; age MSI: HR = 1.04, P < 0.001, ROC-AUC = 0.84, P < 0.001; GRACE score: ROC-AUC = 0.822, P < 0.001] and post-discharge all-cause mortality (age SI: HR = 1.05, P < 0.001, ROC-AUC = 0.78, P = 0.001; age MSI: HR = 1.05, P < 0.001, ROC-AUC = 0.789, P < 0.001; GRACE score: ROC-AUC = 0.812, P < 0.001).

CONCLUSION

Age SI and age MSI are stronger predictors than SI and MSI for in-hospital cardiovascular events, and 6-month and long-term all-cause mortality in STEMI patients undergoing emergency PCI. Age SI and age MSI appear to be convenient and simpler indicators than the GRACE score.

Shock Index in Patients Presenting With Acute Heart Failure: A Multicenter Multinational Observational Study

Shock index (SI) has a prognostic role in coronary heart disease; however, data on acute heart failure (AHF) are lacking. We evaluated the predictive values of SI in patients with AHF. Data were retrospectively analyzed from the Gulf Acute Heart Failure Registry. Patients were categorized into low SI versus high SI based on the receiver operating characteristic curves. Primary outcomes included cardiogenic shock (CS) and mortality. Among 4818 patients with AHF, 1143 had an SI ≥0.9. Compared with SI <0.9, patients with high SI were more likely males, younger, and having advanced New York Heart Association class, fewer cardiovascular risk factors and less prehospital β-blockers and angiotensin-converting enzyme inhibitor use. Shock index had significant negative correlations with age, pulse pressure, mean arterial pressure, and left ventricle ejection fraction and had positive correlation with hospital length of stay. Shock index ≥0.9 was significantly associated with higher composite end points, in-hospital, and 3-month mortality. Shock index ≥0.9 had 96% negative predictive value (NPV) and 3.5 relative risk for mortality. Multivariate regression analysis showed that SI was independent predictor of mortality and CS. With a high NPV, SI is a simple reliable bedside tool for risk stratification of patients with AHF. However, this conclusion needs further support.

The value of shock index in prediction of cardiogenic shock developed during primary percutaneous coronary intervention

BACKGROUND

Shock index(SI) is a conventional predictive marker for haemodynamic state. Its breakpoint varies by different conditions according to previous studies. The current study was performed to evaluate the capability of SI in prediction of cardiogenic shock(CS) developed during primary percutaneous coronary intervention (pPCI).

METHODS

Total 870 patients of ST segment elevation myocardial infarction(STEMI) who were haemodynamic stable before pPCI were involved in the study. In this cohort, 625 consecutive patients composed analysis series and 245 consecutive patients composed validation series. Multivariate regression analysis was used to evaluate whether SI was a significant predictor of developed CS and Hosmer-Lemeshow test was used to assess the goodness of model fitness. Receiver-operating characteristics (ROC) analysis was used to compare the predictive capability of SI with other predictors. The sensitivity, specificity, accuracy, positive and negative predictive values of SI at different cutoff values was compared to identify a best breakpoint.

RESULTS

In the analysis series, SI and Killips classification were identified as independent predictors. ROC analysis demonstrated the diagnostic capability of SI was superior to pre-procedural systolic blood pressure(SBP) or heart rate(HR) alone (0.8113 vs 0.7582, P = 0.04 and 0.8113 vs 0.7111, P < 0.001). The diagnostic capability of SI was equivalent to that of combination of SBP, HR and Killips claasification(0.8133 vs 0.8137, P = 0.97). SI had a high specificity and low sensitivity. When the cutoff value was set at 0.93, the positive predictive value, negative predictive value and diagnostic accuracy was 42.6%, 95.1% and 87.4% respectively. In validation series, the area under ROC curve was 0.8245, which was similar to that in the analysis series. The positive predictive value, negative predictive value and diagnostic accuracy at the cutoff value of 0.93 was 53.8%, 93.2% and 88.9% respectively.

CONCLUSIONS

SI has a high predictive accuracy for developing CS during pPCI in STEMI patients. It is an excellent exclusion diagnosis index rather than confirmative diagnosis index.

Management of postpartum hemorrhage: how to improve maternal outcomes?

Postpartum hemorrhage is the leading cause of maternal mortality and severe morbidity. Despite efforts to improve maternal outcomes, management of postpartum hemorrhage still faces at least four challenges, discussed in this review. First, current definitions for severe postpartum hemorrhage hamper early identification of women with a high risk of adverse outcomes. Adaptations to the definitions and the use of clinical tools such as shock index and early warning systems may facilitate this early identification. Second, surgical and radiological interventions to prevent hysterectomy are not always successful. More knowledge on the influence of patient and bleeding characteristics on the success rates of these interventions is necessary. Scarce data suggest that early timing of intrauterine balloon tamponade may improve maternal outcomes, whereas early timing of arterial embolization seems to be unrelated to maternal outcomes. Third, fluid resuscitation with crystalloids and colloids is unavoidable in the early phases of postpartum hemorrhage but may result in dilutional coagulopathy. Effects of different volumes of clear fluids on the occurrence of dilutional coagulopathy and maternal outcomes is unknown. Fourth, a better understanding of diagnosis and correction of coagulopathy during postpartum hemorrhage is needed. Low plasma fibrinogen levels at the start of postpartum hemorrhage predict progression to severe hemorrhage, but standard coagulation screens are time consuming. A solution may be point-of-care coagulation testing; however, clinical usefulness during postpartum hemorrhage has not been demonstrated. To date, early administration of tranexamic acid is the only hemostatic intervention that was proven to improve outcomes in women with postpartum hemorrhage.

Modified shock index: A bedside clinical index for risk assessment of ST-segment elevation myocardial infarction at presentation

INTRODUCTION

Prompt identification of higher-risk patients presenting with ST-segment elevation myocardial infarction (STEMI) is crucial to pursue a more aggressive approach.

OBJECTIVE

We aimed to assess whether the modified shock index (MSI), the ratio of heart rate to mean arterial pressure, could predict six-month mortality among patients admitted with STEMI.

METHODS

A retrospective observational cohort study was performed in a single center including 1158 patients diagnosed with STEMI, without cardiogenic shock on admission, between July 2009 and December 2014. They were divided into two groups: group 1 - patients with MSI<0.93 (72%); group 2 - patients with MSI≥0.93 (28%). The primary endpoint was six-month all-cause mortality.

RESULTS

MSI≥0.93 identified patients who were more likely to have signs of heart failure (p=0.002), anemia (p<0.001), renal insufficiency (p=0.014) and left ventricular systolic dysfunction (p=0.045). They more often required inotropic support (p<0.001), intra-aortic balloon pump (p<0.001) and mechanical ventilation (p<0.001). Regarding in-hospital adverse events, they had a higher prevalence of malignant arrhythmias (p=0.01) and mechanical complications (p=0.027). MSI≥0.93 was an independent predictor of overall six-month mortality (adjusted HR 2.00, 95% CI 1.20-3.34, p=0.008).

CONCLUSION

MSI was shown to be a valuable bedside tool which can rapidly identify high-risk STEMI patients at presentation.

Predictors of mortality in ST-elevation MI patients: A prospective study

We aimed to define factors predicting mortality in patients having ST elevation myocardial infarction (STEMI) who had Primary Percutaneous Coronary Intervention (PCI) in our setting.This is a prospective study on patients presenting to the emergency department with STEMI who underwent PCI during a 12-month period. Physiological parameters were calculated using the vital signs and age of patients. Time-based factors in the institutional protocol were collected. Univariate analysis was performed to define significant factors that affected mortality. Significant factors were then entered into a logistic regression model. Factors significantly affecting mortality were defined. Receiving operating characteristic curve was applied to define the best predictors of mortality.A total of 167 consecutive patients were studied; 128 (76.6%) were males. The mean (SD) age of the patients was 61.9 (12.8) years. The logistic regression model showed that significant factors were age (P = .002), Modified Shock Index, MSI (P = .028), systolic blood pressure (P = .028), and time between consultation and activation of catheter laboratory (P = .047). The cut-off points with best prediction of mortality were age of 71.5 years, systolic blood pressure of less than 95 mmHg, MSI of 0.85, and a time more than 3.5 minutes between consultation and activation of catheter laboratory.Our study shows that significant predictors of 30-days mortality of STEMI were age, systolic blood pressure on presentation, MSI, and the time between consultation and catheter laboratory activation. Improving prehospital resuscitation and activation of the catheter laboratory by emergency physicians may reduce mortality in our setting.

Derivation and Validation of Shock Index as a parameter for Predicting Long-term Prognosis in Patients with Acute Coronary Syndrome

The objective of this study was to examine whether shock index (SI), defined by ratio of heart rate and systolic blood pressure, can predict long-term prognosis of acute coronary syndrome (ACS) in patients undergoing percutaneous coronary intervention (PCI) and to compare prognostic accuracy of SI with the Global Registry of Acute Coronary Events (GRACE) risk score. This study included individuals from 2 independent cohorts: derivation cohort (n = 2631) and validation cohort (n = 963). In the derivation cohort, we derived that higher admission SI was associated with a greater risk of long-term all-cause mortality [HR = 4.104, 95% CI 1.553 to 10.845, p = 0.004] after adjusting for covariates. We validated this finding in the validation cohort [HR = 10.091, 95% CI 2.205 to 46.187, p = 0.003]. Moreover, admission SI had similar performance to the GRACE score in determining all-cause mortality risk in both cohorts (derivation cohort, admission SI vs. GRACE, z = 1.919, p = 0.055; validation cohort, admission SI vs. GRACE, z = 1.039, p = 0.299). In conclusion, admission SI is an independent predictor of adverse outcome in ACS patients undergoing PCI, and can identify patients at high risk of death. SI and the GRACE score showed similar performance in predicting all-cause mortality, and SI is more readily obtained than the GRACE score.

The prognostic value of shock index for the outcomes of acute myocardial infarction patients: A systematic review and meta-analysis

BACKGROUND

Several studies have revealed that high shock index (SI) is a risk factor for acute myocardial infarction (AMI) patients. These studies do not give a systematic review in this issue. Therefore, we conducted a systematic review and meta-analysis to determine the effect of high SI on the prognosis of AMI patients.

METHODS

We did a systematic search of PubMed, Embase, and the Cochrane Library, using various combinations of keywords such as "shock index," "shock-index," "acute myocardial infarction," "ST elevation myocardial infarction," "non-ST segment elevation myocardial infarction," "STEMI," "NSTEMI," "AMI," and "MI" for eligible studies published up to December 23, 2016. The 3 primary outcomes for this analysis were all-cause in-hospital mortality, short-term adverse outcomes, and long-term adverse outcomes.

RESULTS

Database searches retrieved 226 citations. Finally, 8 studies enrolling 20,404 patients were eventually included in the analysis. High SI was associated with an increased in-hospital mortality (pooled RR = 10.96, 95% CI: 2.00-59.94, P = .01). Adverse outcomes were significantly higher in the high SI group compared to the low SI group (pooled RR = 1.93, 95% CI: 1.10-3.39, P = .02; I = 95%). Individuals with high SI had an increased risk of long-term adverse outcomes (pooled RR = 2.31, 95% CI: 1.90-2.81, P < .001) compared to low SI.

CONCLUSION

High SI may increase the in-hospital mortality, short-term, and long-term adverse outcomes in AMI patients.

Risk factors of late cardiogenic shock and mortality in ST-segment elevation myocardial infarction patients

Background:

The incidence of cardiogenic shock (CS) in patients with ST-segment elevation myocardial infarction (STEMI) is as high as 10%. The majority of patients are thought to develop CS after admission (late CS), but the incidence in a contemporary STEMI cohort admitted for primary percutaneous intervention remains unknown.

Aim:

The aim of this study was to assess the incidence and time of CS onset in patients with suspected STEMI admitted in two high-volume tertiary heart centres and to assess the variables associated with the development of late CS.

Methods:

We included consecutive patients admitted for acute coronary angiography with suspected STEMI in a 1-year period. Cardiogenic shock was based on clinical criteria and subdivided into patients with shock on admission, patients developing shock during catheterisation and patients developing shock later during hospitalisation. Follow-up for all-cause mortality was done using registries.

Results:

A total of 2247 patients with suspected STEMI were included, whereof 225 (10%) developed CS. The majority (56%) had CS on admission, 16% developed CS in the catheterisation laboratory and 28% developed late CS. Thirty-day mortality was 3.1% versus 47% in non-CS versus CS patients ( plogrank < 0.0001). Age, stroke, time from symptom onset to intervention, anterior STEMI, heart rate/systolic blood pressure ratio and being comatose after resuscitation from cardiac arrest were independently associated with the development of late CS.

Conclusion:

In this study, 10% of patients admitted with suspected STEMI for acute coronary angiography presented with or developed CS. Most were in shock on admission. Irrespective of the timing of shock, mortality was high.

Shock Index More Sensitive Than Cardiogenic Shock in ST-Elevation Myocardial Infarction Treated by Primary Percutaneous Coronary Intervention

BACKGROUND

Cardiogenic shock (CS) is a strong predictor of mortality in patients with ST-elevation myocardial infarction (STEMI), but there is evidence that shock index (SI), taking into account both blood pressure and heart rate, is a more sensitive and powerful predictor. We investigated the independent impact of SI and CS on 30-day and 1-year mortality in patients with STEMI, treated by primary percutaneous coronary intervention (PCI).

METHODS AND RESULTS

In 7,412 consecutive patients with STEMI treated with primary PCI, the predictive value of either SI or CS on 1-year mortality was assessed. Best cut-off value of SI, determined using receiver operating characteristic (ROC) curve, was 0.7, with an ROC AUC of 0.66 (95% CI: 0.65-0.67), compared with an ROC AUC of 0.60 (95% CI: 0.59-0.61) for CS (P<0.001). At admission, 387 patients (5.2%) had CS and 1,567 patients (21.1%) had SI ≥0.7. The adjusted hazard ratio of mortality in patients with SI ≥0.7 and in CS patients was, respectively, 3.3 (95% CI: 2.4-4.6) and 3.1 (95% CI: 2.1-4.6) after 30 days, and 2.3 (95% CI: 1.8-2.9) and 3.1 (95% CI: 2.2-4.2) after 1 year.

CONCLUSIONS

SI identifies more patients with increased risk of mortality, and seems to be a more sensitive prognostic predictor than CS in patients with STEMI treated by primary PCI.

Cardiogenic Shock Predicts Long-term Mortality in Hospital Survivors of STEMI Treated With Primary Percutaneous Coronary Intervention

BACKGROUND

ST-segment elevation myocardial infarction (STEMI) complicated by cardiogenic shock (CS) has a poor prognosis. Recently published data suggested, however, that CS does not affect long-term mortality in hospital survivors of STEMI. We investigated whether this could be confirmed in a larger cohort.

HYPOTHESIS

STEMI complicated by CS leads to worse long-term survival.

METHODS

A prospective cohort study was performed in 7412 consecutive patients with STEMI treated by primary percutaneous coronary intervention (angioplasty). The predictive value of CS on long-term mortality was assessed in hospital survivors. Multivariate analysis, adjusting for differences in baseline variables, was performed to assess the independent prognostic value of CS.

RESULTS

Cardiogenic shock was observed in 387 patients (5.2%). The total in-hospital mortality was 254 (3.4%), and mortality was significantly higher in patients with CS (20.0% vs 2.6%; P < 0.001). The 1-year mortality in hospital survivors was 10.3% in patients with CS and 3.9% in patients without CS (P < 0.001). After multivariate analysis, CS was still a significant predictor of long-term mortality in hospital survivors (hazard ratio: 2.6, 95% confidence interval: 1.64-4.01).

CONCLUSIONS

Cardiogenic shock remains a strong predictor of long-term mortality in hospital survivors of STEMI treated by primary percutaneous coronary intervention.

Long-Term Prognostic Implications of the Admission Shock Index in Patients With Acute Myocardial Infarction Who Received Percutaneous Coronary Intervention

The admission shock index (SI) enables prediction of short-term prognosis. This study investigated the prognostic implications of admission SI for predicting long-term prognoses for acute myocardial infarction (AMI). The participants were 680 patients with AMI who received percutaneous coronary intervention. Shock index is the ratio of heart rate and systolic blood pressure. Patients were classified as admission SI <0.66 (normal) and ≥0.66 (elevated; 75th percentile). The end point was 5-year major adverse cardiac events (MACEs). Elevated admission SI was seen in 176 patients. Peak creatine kinase levels were significantly higher and left ventricular ejection fraction was lower in the elevated SI group, which had a worse MACEs. In multivariate Cox regression analysis, SI ≥0.66 was a risk factor for MACE. Elevated admission SI was associated with poorer long-term prognosis.