Most Frequent Manifestation of Blunt Myocardial Contusion

Premature ventricular contractions (PVCs) are the most frequent manifestation of blunt myocardial contusion.

Pathophysiology and Clinical Manifestations

Blunt myocardial contusion encompasses a spectrum of injuries from minor contusion to fatal cardiac rupture, with arrhythmias being a common manifestation 1, 2
When myocardial contusion occurs, it stretches the cell membrane, leading to activation of ion channels through mechanical-electrical coupling that triggers ventricular arrhythmias 1
Premature ventricular contractions are the most commonly observed arrhythmia in patients with blunt myocardial contusion 1

In a prospective study involving 125 patients with blunt chest trauma, serious arrhythmias such as premature ventricular beats were among the most common cardiac complications observed 1
Another prospective study of 147 patients with major blunt chest injury found that 10 patients developed ectopic rhythms, with ventricular arrhythmias being predominant 3
The European Association of Cardiovascular Imaging specifically notes that persistent arrhythmias, particularly premature ventricular contractions, raise suspicion of cardiac trauma and indicate the need for rapid echocardiographic evaluation 1

Initial evaluation should include ECG, cardiac troponin measurement, and echocardiography in patients with suspected cardiac injury 4
Transthoracic echocardiography (TTE) is the first-line imaging modality for evaluating patients with suspected blunt cardiac trauma presenting with abnormal ECG and elevated cardiac troponin levels 1
When wall motion abnormality is present in the absence of elevated high-sensitivity cardiac troponins, a diagnosis of myocardial concussion can be made, which commonly manifests as ventricular arrhythmias 1

Premature ventricular contractions: Most common arrhythmia, directly related to myocardial contusion 1
Atrial fibrillation: Less common than PVCs but can occur in severe cases 1
Atrioventricular block: Can occur but is less frequent than ventricular arrhythmias 1
Atrial flutter and premature atrial contractions: Relatively uncommon manifestations compared to ventricular arrhythmias 1

Patients with myocardial contusion should be observed for 24 to 48 hours for arrhythmias, particularly PVCs 5
Hemodynamically unstable patients with ECG changes and elevated cardiac troponins should be managed with advanced cardiac life support followed by echocardiography evaluation 1
Treatment typically involves monitoring and addressing symptomatic dysrhythmias rather than extensive diagnostic testing 3

Despite the frequency of arrhythmias, particularly PVCs, the long-term prognosis for patients with myocardial contusion is generally favorable 6
A prospective study found that none of the patients with myocardial contusion experienced acute cardiac complications during hospitalization, and follow-up assessments revealed no new pathologies in most patients 6