PoCUS may aid early diagnosis and revascularization of occult occlusive MI in ICU patients

USA: Cardiac PoCUS (point-of-care ultrasound) may help identify occult occlusive myocardial infarction (OOMI) earlier than standard evaluation and may expedite definitive management in patients in the emergency department, states the study results published in The American Journal of Emergency Medicine. PoCUS may be used as a rapid, reliable, diagnostic tool in ED.

A greater proportion of patients are receiving their initial care and diagnostic testing in emergency departments (EDs) With the ever-changing landscape of health care delivery globally. Expediting triage and time to diagnosis is crucial in decreasing morbidity and mortality in critically ill patients and significant efforts have been made for its achievement. Point-of-care ultrasound (PoCUS) in the ED is one of the point-of-care testing tools available to the emergency physician which answers specific clinical questions that narrow differentials, guide clinical therapy, and direct consultations and disposition.

Electrocardiographically occult occlusive myocardial infarction (OOMI) is a coronary artery occlusion requiring revascularization. Occlusive myocardial infarction diagnosis without ECG ST-elevation can take hours and delayed diagnosis is associated with increased mortality. Left ventricular (LV) wall motion abnormalities (WMA) visible on PoCUS can expedite OOMI diagnosis.

Curtis Xu, University of Connecticut School of Medicine, USA, and colleagues sought to determine whether PoCUS demonstrating WMA expedites revascularization time when performed on emergency department patients being evaluated for OOMI.

Researchers conducted a single-center, retrospective cohort study over a 38-month period that included adults aged ≥35 years who were presented to the ED with the potential acute coronary syndrome (n=234). Patients evaluated by the emergency physician with PoCUS for LV function, an ECG, and a standard troponin I biomarker assay were included. Patients with ST-segment elevation myocardial infarction (STEMI), prior LV dysfunction, fever ≥100.4 °F, or hypotension was excluded. Structured chart abstraction was performed for relevant demographic and clinical characteristics. The outcome was set as the time for revascularization.

Key findings of the study,

• 23 patients had OOMI; of those, 20 had elevated troponins and 14 had WMA.

• Median time, ED arrival to revascularization with WMA(n=14) was 432minutes ( IQR 209-1300) vs without WMA(n=9) was 2158 (IQR 552-3390) minutes.

• POCUS timing before:

o Troponin (n=234): 36 (IQR, 9-68) minutes.

o First elevated troponin (n=85): 39 (IQR, 23-96) minutes.

o First troponin elevation in patients with OOMI (n=20): 43 (IQR, 9-263) minutes.

The authors conclude that electrocardiographically occult occlusive myocardial infarction (OOMI) may be visible early on point-of-care ultrasound (POCUS) in the emergency department (ED). POCUS can detect wall motion abnormalities within minutes and expedites revascularization time

Curtis Xu, Andrew Melendez, Thuy Nguyen, Justin Ellenberg, Ambika Anand, João Delgado, Meghan Kelly Herbst, Point-of-care ultrasound may expedite diagnosis and revascularization of occult occlusive myocardial infarction, The American Journal of Emergency Medicine, 2022, https://doi.org/10.1016/j.ajem.2022.06.010