24-hour Telemetry Monitoring May Not be Necessary for Patients With an Isolated Sternal Fracture and Minor ECG Abnormalities or Troponin Elevation: A Southern California Multicenter Study.

Background: Current guidelines recommend 24-hour telemetry monitoring for isolated sternal fractures (ISFs) with electrocardiogram (ECG) abnormalities or troponin elevation. However, a single-center study suggested ISF patients with minor ECG abnormalities (sinus tachycardia/bradycardia, nonspecific arrhythmia/ST-changes, and bundle branch block) may not require 24-hour telemetry monitoring. This study sought to corroborate this, hypothesizing ISF patients would not develop blunt cardiac injury (BCI).

Materials & Methods: A retrospective study was performed at 8 trauma centers (1/2018-8/2020). Patients with ISF (abbreviated injury scale <2 for the head/neck/face/abdomen/extremities) and minor ECG abnormalities or troponin elevations were included. Patients with multiple rib fractures or hemothorax/pneumothorax were excluded. The primary outcome was an echocardiogram confirmed BCI. The secondary outcome was significant BCI defined as cardiogenic shock, dysrhythmia requiring treatment, post-traumatic cardiac structural defects, unexplained hypotension, or cardiac-related procedures. Descriptive statistics were performed.

Results: Of 124 ISF patients with minor ECG abnormalities or troponin elevation, 90% were admitted with a mean stay of 35 hours. Echocardiogram was performed for 31.5% of patients, 10 (25.6%) of which had abnormalities. However, no patient had BCI diagnosed on echocardiography. In total, 2 patients (1.6%) had a significant BCI (atrial fibrillation and supraventricular tachycardia at 10 and 82 hours after injury). No patient died.

Conclusions: Following ISF with minor ECG changes or troponin elevation, <2% suffered significant BCI, and none had an echocardiogram diagnosed BCI, despite >30% receiving echocardiogram. These findings challenge the dogma of mandatory observation periods following ISF with associated ECG abnormalities and support the lack of utility for routine echocardiography in these patients.