Establishment of a prognostic model based on the Sequential Organ Failure Assessment score for patients with first-time acute myocardial infarction

Abstract

Objective: This study aimed to identify the prognostic factors of patients with first-time acute myocardial infarction (AMI) and to establish a nomogram for prognostic modeling.

Methods: We studied 985 patients with first-time AMI using data from the Multi-parameter Intelligent Monitoring for Intensive Care database and extracted their demographic data. Cox proportional hazards regression was used to examine outcome-related variables. We also tested a new predictive model that includes the Sequential Organ Failure Assessment (SOFA) score and compared it with the SOFA-only model.

Results: An older age, higher SOFA score, and higher Acute Physiology III score were risk factors for the prognosis of AMI. The risk of further cardiovascular events was 1.54-fold higher in women than in men. Patients in the cardiac surgery intensive care unit had a better prognosis than those in the coronary heart disease intensive care unit. Pressurized drug use was a protective factor and the risk of further cardiovascular events was 1.36-fold higher in nonusers.

Conclusion: The prognosis of AMI is affected by age, the SOFA score, the Acute Physiology III score, sex, admission location, type of care unit, and vasopressin use. Our new predictive model for AMI has better performance than the SOFA model alone.

Keywords: Acute myocardial infarction; Sequential Organ Failure Assessment score; intensive care; intensive care unit; prognosis; vasopressin.

Figure 1.

Inclusion and exclusion process of the study sample. MIMIC, Multi-parameter Intelligent Monitoring for Intensive Care; AMI, acute myocardial infarction.

Figure 2.

Nomogram for predicting 30-, 60-, and 90-day probability of survival from acute myocardial infarction. SOFA, Sequential Organ Failure Assessment; APSIII, Acute Physiology Score III; vaso, vasopressin; CCU, coronary heart disease intensive care unit; CSRU, cardiac surgery intensive care unit; MICU, medical intensive care unit; SICU, stroke intensive care unit; TSICU, surgical intensive care unit.

Figure 3.

ROC curves. The area under the ROC was used to evaluate the performance of the new nomogram. (a–c) Results of the training cohort. (d–f) Results of the test cohort. ROC, receiver operating characteristic; AUC, area under the curve; SOFA, Sequential Organ Failure Assessment.

Figure 4.

Calibration curves. Calibration curves for 30-, 60-, and 90-day probability of survival from acute myocardial infarction show calibration of each model in terms of the agreement between the predicted probabilities and observed outcomes of the training cohort (a–c) and validation cohort (d–f).

Figure 5.

Decision curves for a nomogram for 30-, 60-, and 90-day prediction of mortality of acute myocardial infarction in the training set (a) and validation set (b). All of the red lines in the figure are above the green lines, and therefore, the area under the curve is larger for the new model than for the Sequential Organ Failure Assessment model.