Utility of hand-held ultrasound performed by cardiology fellows in patients presenting with suspected ST elevation myocardial infarction

Background: In academic hospitals, cardiology fellows may be the first point of contact for patients presenting with suspected STE elevation myocardial infarction (STEMI) or acute coronary syndrome (ACS). In this study, we sought to determine the role of handheld ultrasound (HHU) in patients with suspected acute MI (AMI) when used by fellows in training, its association with year of training in cardiology fellowship, and its influence on clinical care. Methods: This prospective study’s sample population was comprised of patients who presented to Loma Linda University Medical Center Emergency Department with suspected acute STEMI. On call cardiology fellows performed bedside cardiac HHU at time of AMI activation. All patients subsequently underwent standard TTE. The impact of the detection of WMA on HHU in regards to clinical decision making, including whether the patient would undergo urgent invasive angiography, was also evaluated. Results: 82 patients (mean age 65 years, 70% male) were included. The use of HHU by cardiology fellows resulted in a concordance correlation coefficient of 0.71 (95% confidence interval: 0.58 - 0.81) between HHU and TTE for LVEF, and a concordance correlation coefficient of 0.76 (0.65 - 0.84) for wall motion score index (WMSI). Patients with WMA on HHU were more likely to undergo invasive angiogram during hospitalization (96% vs 75%, p<0.01). The time interval between performance of HHU to initiation of cardiac catheterization (time-to-cath) was shorter in patients with abnormal vs normal HHU exams (58 ± 32 minutes versus 218 ± 388 min, p=0.06). Lastly, among patients who underwent angiography, those with WMA were more likely to undergo angiography within 90 minutes of presentation (96% vs 66%, p<0.001). Conclusion: HHU can be reliably used by cardiology fellows in training for measurement of LVEF and assessment of wall motion abnormalities, with good correlation to findings obtained via standard TTE. HHU-identified WMA at first contact were associated with higher rates of angiography as well as sooner angiography compared to patients without WMA.