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

Association between the shock index on admission and in-hospital mortality in the cardiac intensive care unit

BACKGROUND

An elevated shock index (SI) predicts worse outcomes in multiple clinical arenas. We aimed to determine whether the SI can aid in mortality risk stratification in unselected cardiac intensive care unit patients.

METHODS

We included admissions to the Mayo Clinic from 2007 to 2015 and stratified them based on admission SI. The primary outcome was in-hospital mortality, and predictors of in-hospital mortality were analyzed using multivariable logistic regression.

RESULTS

We included 9,939 unique cardiac intensive care unit patients with available data for SI. Patients were grouped by SI as follows: < 0.6, 3,973 (40%); 0.6-0.99, 4,810 (48%); and ≥ 1.0, 1,156 (12%). After multivariable adjustment, both heart rate (adjusted OR 1.06 per 10 beats per minute higher; CI 1.02-1.10; p-value 0.005) and systolic blood pressure (adjusted OR 0.94 per 10 mmHg higher; CI 0.90-0.97; p-value < 0.001) remained associated with higher in-hospital mortality. As SI increased there was an incremental increase in in-hospital mortality (adjusted OR 1.07 per 0.1 beats per minute/mmHg higher, CI 1.04-1.10, p-Value < 0.001). A higher SI was associated with increased mortality across all examined admission diagnoses.

CONCLUSION

The SI is a simple and universally available bedside marker that can be used at the time of admission to predict in-hospital mortality in cardiac intensive care unit patients.

Factors Associated With Hospital Mortality in Acute Myocardial Infarction

Aim    To determine clinical and laboratory parameters associated with in-hospital mortality in patients with acute myocardial infarction and to develop a multifactorial prognostic model of in-hospital mortality.Material and methods    This was a study based on the 2019-2020 Registry of acute coronary syndrome of the Tyumen Cardiology Research Center, a branch of the Tomsk National Research Medical Center. The study included 477 patients with ST-segment elevation acute myocardial infarction (AMI), 617 patients with non-ST segment elevation AMI, and 26 patients with unspecified AMI. In-hospital mortality was 6.0 % (n=67). Clinical and laboratory parameters were assessed on the day of admission. The separation power of indicators associated with in-hospital mortality was determined using a ROC analysis. The data array of each quantitative parameter was converted into a binary variable according to the obtained cut-off thresholds, followed by creation of a multifactorial model for predicting in-hospital mortality using a stepwise analysis with backward inclusion (Wald). The null hypothesis was rejected at p<0.05.Results    The multivariate model for prediction of in-hospital mortality included age (cut-off, 72 years), OR 3.0 (95 % CI: 1.5-5.6); modified shock index (cut-off threshold, 0.87), OR 1.5 (95 % CI: 1.1-2.0); creatine phosphokinase-MB (cut-off threshold, 32.8 U / L), OR 4.1 (95 % CI: 2.2-7.7); hemoglobin (121.5 g / l), OR 1.7 (95 % CI: 1.2-2.3); leukocytes (11.5×109 / l), OR 1.9 (95 % CI: 1.3-2.6); glomerular filtration rate (60.9 ml / min), OR 1.7 (95 % CI: 1.2-2.2); left ventricular ejection fraction (42.5 %), OR 4.1 (95 % CI: 2.0-8.3); and size of myocardial asynergy (32.5 %), OR 2.6 (95 % CI: 1.4-5.0).Conclusions    Independent predictors of in-hospital mortality in AMI are age, modified shock index, creatine phosphokinase-MB, peripheral blood leukocyte count, hemoglobin concentration, left ventricular ejection fraction, size of myocardial asynergy, and glomerular filtration rate. The in-hospital mortality model had a high predictive potential: AUC 0.930 (95 % CI: 0.905-0.954; p <0.001) with a cutoff threshold of 0.15; sensitivity 0.851, and specificity 0.850.

Comparative analysis of four established risk scores for prediction of in-hospital mortality in patients undergoing primary percutaneous coronary intervention

OBJECTIVE

This study was conducted to compare the predictive power of Shock Index (SI), TIMI Risk Index (TRI), LASH Score, and ACEF Score for the prediction of in-hospital mortality in a contemporary cohort of ST-segment elevation myocardial infarction (STEMI) patients undergoing primary percutaneous coronary intervention (PCI) at a tertiary care cardiac center of a developing country.

METHODS

Consecutive patients diagnosed with STEMI and undergoing primary PCI were included in this study. SI, TRI, LASH, and ACEF were computed and their predictive power was assessed as the area under the curve (AUC) on the receiver operating characteristics (ROC) curve analysis for in-hospital mortality.

RESULTS

We included 977 patients, 780 (79.8%) of which were male, and the mean age was 55.6 ± 11.5 years. The in-hospital mortality rate was 4.3% (42). AUC for TRI was 0.669 (optimal cutoff: ≥17.5, sensitivity: 76.2%, specificity: 45.6%). AUC for SI was 0.595 (optimal cutoff: ≥0.9, sensitivity: 21.4%, specificity: 89.8%). AUC for LASH score was 0.745 (optimal cutoff: ≥0, sensitivity: 76.2%, specificity: 66.9%). AUC for the ACEF score was 0.786 (optimal cutoff: ≥1.66, sensitivity: 71.4%, specificity: 73.5%).

CONCLUSION

In conclusion, ACEF showed sufficiently high predictive power with good sensitivity and specificity compared to other three scores. These simplified indices based on readily available hemodynamic parameters can be reliable alternatives to the computational complex scoring systems for the risk stratification of STEMI patients.

Modified Shock Index as Simple Clinical Independent Predictor of In-Hospital Mortality in Acute Coronary Syndrome Patients: A Retrospective Cohort Study

Introduction

Despite being the current most accurate risk scoring system for predicting in-hospital mortality for patients with acute coronary syndrome (ACS), the Global Registry of Acute Coronary Events (GRACE) risk score is time consuming due to the requirement for electrocardiography and laboratory examinations. This study is aimed to evaluate the association between modified shock index (MSI), as a simple and convenient index, with in-hospital mortality and revascularization in hospitalized patients with ACS.

Methods

A single-centered, retrospective cohort study, involving 1,393 patients with ACS aged ≥ 18 years old, was conducted between January 2018 and January 2022. Study subjects were allocated into two cohorts: high MSI ≥ 1 (n = 423) and low MSI < 1 group (n = 970). The outcome was in-hospital mortality and revascularization. The association between MSI score and interest outcomes was evaluated using binary logistic regression analysis. The area under the curve (AUC) between MSI and GRACE score was compared using De Long’s method.

Results

Modified shock index ≥ 1 had 61.1% sensitivity and 73.7% specificity. A high MSI score was significantly and independently associated with in-hospital mortality in patients with ACS [odds ratio (OR) = 2.72(1.6–4.58), p < 0.001]. However, ST-segment elevation myocardial infarction (STEMI) and non-STEMI (NSTEMI) patients with high MSI did not significantly increase the probability of revascularization procedures. Receiver operating characteristic (ROC) analysis demonstrated that although MSI and GRACE scores were both good predictors of in-hospital mortality with the AUC values of 0.715 (0.666–0.764) and 0.815 (0.775–0.855), respectively, MSI was still inferior as compared to GRACE scores in predicting mortality risk in patients with ACS (p < 0.001).

Conclusion

Modified shock index, particularly with a score ≥ 1, was a useful and simple parameter for predicting in-hospital mortality in patients presenting with ACS.

Shock index as a predictor for short-term mortality in helicopter emergency medical services: A registry study

BACKGROUND

The value of shock-index has been demonstrated in hospital triage, but few studies have evaluated its prehospital use. The aim of our study was to evaluate the association between shock-index in prehospital critical care and short-term mortality.

METHODS

We analyzed data from the national helicopter emergency medical services database and the Population Register Centre. The shock-index was calculated from the patients' first measured parameters. The primary outcome measure was 1- and 30-day mortality.

RESULTS

A total of 22 433 patients were included. The 1-day mortality was 7.5% and 30-day mortality was 16%. The median shock-index was 0.68 (0.55/0.84) for survivors and 0.67 (0.49/0.93) for non-survivors (P = .316) at 30-days. Association between shock-index and mortality followed a U-shaped curve in trauma (shock-index < 0.5: odds ratio 2.5 [95% confidence interval 1.8-3.4], shock-index > 1.3: odds ratio 4.4 [2.7-7.2] at 30 days). Patients with neurological emergencies with a low shock-index had an increased risk of mortality (shock-index < 0.5: odds ratio 1.8 [1.5-2.3]) whereas patients treated after successful resuscitation from out-of-hospital cardiac arrest, a higher shock-index was associated with higher mortality (shock-index > 1.3: odds ratio 3.5 [2.3-5.4). The association was similar for all ages, but older patients had higher mortality in each shock-index category.

CONCLUSION

The shock-index is associated with short time mortality in most critical patient categories in the prehospital setting. However, the marked overlap of shock-index in survivors and non-survivors in all patient categories limits its predictive value.

The FASILA Score: A Novel Bio-Clinical Score to Predict Massive Blood Transfusion in Patients with Abdominal Trauma

Background

Early identification of patients who may need massive blood transfusion remains a major challenge in trauma care. This study proposed a novel and easy-to-calculate prediction score using clinical and point of care laboratory findings in patients with abdominal trauma (AT).

Methods

Patients with AT admitted to a trauma center in Qatar between 2014 and 2017 were retrospectively analyzed. The FASILA score was proposed and calculated using focused assessment with sonography in trauma (0 = negative, 1 = positive), Shock Index (SI) (0 = 0.50–0.69, 1 = 0.70–0.79, 2 = 0.80–0.89, and 3 ≥ 0.90), and initial serum lactate (0 ≤ 2.0, 1 = 2.0–4.0, and 2 ≥ 4.0 mmol/l). Outcome variables included mortality, laparotomy, and massive blood transfusion (MT). FASILA was compared to other prediction scores using receiver operating characteristics and areas under the curves. Bootstrap procedure was employed for internal validation.

Results

In 1199 patients with a mean age of 31 ± 13.5 years, MT, MT protocol (MTP) activation, exploratory laparotomy (ExLap), and hospital mortality were related linearly with the FASILA score, Injury Severity Score, and total length of hospital stay. Initial hemoglobin, Revised Trauma Score (RTS), and Trauma Injury Severity Score (TRISS) were inversely proportional. FASILA scores correlated significantly with the Assessment of Blood Consumption (ABC) (r = 0.65), Revised Assessment of Bleeding and Transfusion (RABT) (r = 0.63), SI (r = 0.72), RTS (r = − 0.34), and Glasgow Coma Scale (r = − 0.32) and outperformed other predictive systems (RABT, ABC, and SI) in predicting MT, MTP, ExLap, and mortality.

Conclusions

The novel FASILA score performs well in patients with abdominal trauma and offers advantages over other scores.

Electronic supplementary material

The online version of this article (10.1007/s00268-019-05289-0) contains supplementary material, which is available to authorized users.

Prognostic performance of peripheral perfusion index and shock index combined with ESI to predict hospital outcome

INTRODUCTION

Peripheral perfusion index (PPI) and shock index (SI) are considered valuable predictors of hospital outcome and mortality in various operative and intensive care settings. In the present study, we evaluated the prognostic capabilities of these parameters for performing emergency department (ED) triage, as represented by the emergency severity index (ESI).

METHODS

This prospective cross-sectional study included 367 patients aged older than 18 years who visited the ED of a tertiary referral hospital. The ESI triage levels with PPI, SI, and other basic vital sign parameters were recorded for each patient. The hospital outcome of the patients at the end of the ED period, such as discharge, admission to the hospital and death were recorded.

RESULTS

A total of 367 patients (M/F: 178/189) admitted to the ED were categorized according to ESI and included in the study. A decrease in diastolic BP, SpO2 and PPI increased the likelihood of hospitalization and 30-day mortality. Based on univariate analysis, a significant improvement in performance was found by using age, diastolic BP, mean arterial pressure, SpO2, SI and PPI in terms of predicting high acuity level patients (ESI < 3). In the multivariable analysis only SpO2 and PPI were found to predict ESI < 3 patients.

CONCLUSION

Peripheral perfusion index and SI as novel triage instruments might provide useful information for predicting hospital admission and mortality in ED patients. The addition of these parameters to existing triage instruments such as ESI could enhance the triage specificity in unselected patients admitted to ED.

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.

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.

Association between mild thyroid dysfunction and clinical outcome in acute coronary syndrome undergoing percutaneous coronary intervention

BACKGROUND

Thyroid hormones profoundly influence the cardiovascular system, but the effects of mild thyroid dysfunction on the clinical outcome of acute coronary syndrome (ACS) patients undergoing percutaneous coronary intervention (PCI) are not well defined. This study aimed to determine the effect of mild thyroid dysfunction on 12-month prognosis in ACS patients undergoing PCI.

METHODS

In this prospective cohort study with a 12-month follow-up, 1560 individuals were divided into four groups based on thyroid hormone levels upon admission: euthyroidism (used as a reference group), subclinical hypothyroidism, subclinical hyperthyroidism, and low triiodothyronine syndrome (low T3 syndrome). The outcomes measured were all-cause mortality, cardiac mortality, nonfatal rein-farction, and unplanned repeat revascularization.

RESULTS

In this study, the prevalence of mild thyroid dysfunction was 10.8%. Multivariate analysis showed that low T3 syndrome, but not subclinical hypothyroidism or subclinical hyperthyroidism, was associated with a higher rate of all-cause (HR 2.553, 95% CI 1.093-5.964, p = 0.030) and cardiac mortality (HR 2.594, 95% CI 1.026-6.559, p = 0.034), compared with the euthyroidism group.

CONCLUSIONS

Mild thyroid dysfunction was frequent in patients with ACS undergoing PCI. Low T3 syndrome was the predominant feature and was associated with 12-month adverse outcomes in these patients.

MicroRNA-150 restores endothelial cell function and attenuates vascular remodeling by targeting PTX3 through the NF-κB signaling pathway in mice with acute coronary syndrome

MicroRNAs (miRNAs) have been known to function as important regulators in the vascular system, with various physiopathological effects such as vascular remodeling and hypertension modulation. We aimed to explore whether microRNA-150 (miR-150) regulates endothelial cell function and vascular remodeling in acute coronary syndrome (ACS), and the involvement of PTX3 and NF-κB signaling pathway. Ten normal mice and sixty ApoE^-/- mice were chosen, and their coronary artery tissues and endothelial cells were extracted. ApoE^-/- mice were injected with a series of inhibitor or mimic for miR-150, or siRNA against PTX3. The miR-150 expression, NF-κB1, RELA, and PTX3 mRNA expression were assessed by reverse transcription quantitative polymerase chain reaction, and pentraxin-3, p-P50, and p-P65 protein expression by Western blot analysis. Cell viability and migration were assessed by MTT assay and scratch test. Matrigel tube formation assay was employed to determine vascular remodeling of endothelial cells. The dual-luciferase reporter assay verified that PTX3 was a target of miR-150. Mice with ACS presented with decreased miR-150 but increased PTX3. It was observed that the miR-150 mimic and siRNA against PTX3 reduced levels of PTX3, NF-κB1, and RELA in mice, and the miR-150 inhibitor reversed the tendency. The in vitro cell experimentation proved that miR-150 might facilitate endothelial cell proliferation, migration, and restrain vascular remodeling via inhibiting PTX3 expression. On the basis of the results of this study, it was hypothesized that miR-150 could possibly maintain endothelial cell function and suppress vascular remodeling by inhibiting PTX3 through the NF-κB signaling pathway in mice with ACS.