Clinical Outcomes of Early Repatriation for Patients With ST-Segment Elevation Myocardial Infarction: A Propensity-Matched Analysis

Defining and validating comorbidities and procedures in ICD-10 health data in ST-elevation myocardial infarction patients

Administrative health databases are used in research to define comorbid conditions, diagnosis, and procedures. Our objectives were to validate a diagnosis of ST-elevation myocardial infarction (STEMI) and invasive cardiac procedure coding against a comprehensive registry of STEMI patients and determine an optimal algorithm for defining comorbidities using administrative hospitalization and ambulatory databases, but without using a physician claims database, which is unavailable for use in many jurisdictions.A registry of consecutive STEMI patients was used to define a reference cohort and linked to the hospitalization and ambulatory databases. Four administrative case definitions for defining comorbidities, as well as STEMI diagnosis and in-hospital procedures using the International Classification of Diseases, 10th Revision (ICD-10) and the Canadian Classification of Health Interventions (CCI) were evaluated. Metrics were used to evaluate algorithm performance and compare discriminative ability using the C statistic.The 3236 patients had median age of 60 years (interquartile range 52-71) and 75.7% were male. A diagnosis of STEMI was correctly identified in the administrative records for 3043 (94.0%) patients. In-hospital procedures (coronary artery bypass grafting, percutaneous coronary intervention, and angiogram) were well identified using administrative definitions (Kappa statistic 0.83-1.00). Validation of comorbidities varied by condition but an algorithm using 2 inpatient/ambulatory visits in the previous 2 years maximized PPV, ranging from 28.6% for previous heart failure to 95.7% for previous MI. The c statistic was similar for each of the methods, ranging from 0.76 to 0.80.ICD-10 and CCI codes can identify hospitalized STEMI patients with high sensitivity and accurately define in-hospital cardiac procedures. Comorbidities can be defined with high PPV using a definition of 2 inpatient/ambulatory visits in the previous 2 years.

Repatriation to referral hospital after reperfusion of STEMI patients transferred for primary percutaneous coronary intervention: Insights of a Canadian regional STEMI care system

BACKGROUND

In regional systems of ST-segment elevation myocardial infarction (STEMI) care, patients presenting to hospitals without percutaneous coronary intervention (PCI) are transferred to PCI-capable hospitals for primary PCI. Repatriation, a practice whereby such patients are transferred back to non-PCI referral hospitals after reperfusion is prevalent in many jurisdictions, yet little is known of this practice and its safety.

METHODS

We studied 979 consecutive STEMI patients transported from the emergency department and catchment area of two non-PCI hospitals in Ontario, Canada to a regional PCI-hospital for primary PCI between January 2008 and June 2014. Logistic regression modeling was performed to determine factors associated with delayed repatriation beyond 24 hours and to evaluate the association between repatriation and index-admission mortality.

RESULTS

Eight hundred and fifteen (83.2%) patients were repatriated with 524 (65.2%) patients repatriated within 24 hours. Factors independently associated with delayed repatriation included systolic blood pressure (OR 1.03 per 5 mmHg decrease, 95% CI 1.01-1.06, P= .04), requirement for mechanical ventilation (OR 24.9, 95% CI 5.4-115.3, P< .0001), ventricular arrhythmia (OR 3.0, 95% CI 1.3-6.6, P= .01), infarct-related artery (P= .03), final TIMI flow grade (P= .01) and access-site complications (OR 2.36, 95% CI 1.04-5.4, P= .04). After repatriation, 9 (1.3%) patients returned to the PCI-hospital for urgent care, and 16 (2.0%) died during index-admission. After adjustment, repatriation was not associated with increase in index-admission mortality (adjusted OR 0.46, 95% CI 0.16-1.32, P= .15).

CONCLUSIONS

In a regional STEMI care system in Ontario, Canada, patients are routinely repatriated to non-PCI hospitals after primary PCI. This practice was associated with very low and acceptable rate of return to the PCI-hospital during index-admission without an adverse impact on short-term outcomes.