Cardiac Contusion (Blunt Cardiac Injury)

How a heart gets bruised

The heart sits in the middle of the chest, directly behind the breastbone, with the right ventricle closest to the front. Blunt force injures it in several ways:

• Direct compression between the sternum and the spine, as when the chest strikes a steering wheel
• Deceleration, when the body stops suddenly but the heart keeps moving, stretching it against its attachments
• Sudden pressure changes inside the chest and heart chambers during crush injuries
• Blast injury from explosions

Motor vehicle crashes cause most cases, followed by falls from height, crush injuries, assaults, sports and sometimes CPR. The right ventricle and right atrium are most often injured because of their position.

For a patient-focused overview of symptoms and recovery, see our page on heart contusion.

The spectrum of blunt cardiac injury

Bruised heart symptoms

Symptoms are often nonspecific and overlap with chest wall injury:

• chest pain, often behind the sternum
• palpitations or an irregular pulse
• fast heart rate not explained by pain or blood loss
• breathlessness
• lightheadedness, low blood pressure or fainting
• in severe injury: signs of cardiac tamponade (low blood pressure, distended neck veins, muffled heart sounds) or heart failure

Many people with confirmed contusions have no symptoms that point specifically to the heart, which is why screening tests are used.

Common associated injuries

• sternal fracture and rib fractures
• pulmonary contusion and pneumothorax
• injury to the aorta
• flail chest

Diagnosis

Trauma guidelines recommend a structured approach:

1. 12-lead ECG in all patients with suspected blunt cardiac injury. Abnormalities include sinus tachycardia, premature beats, atrial fibrillation, bundle branch block (especially right), ST changes and heart block.
2. Troponin blood test, often repeated. Combined with a normal ECG, a normal troponin effectively rules out significant blunt cardiac injury, and the patient does not need cardiac monitoring for this reason.
3. Echocardiogram for patients with an abnormal ECG or troponin, low blood pressure, or suspected structural injury. It shows wall motion problems, pericardial fluid, valve damage and septal defects.
4. Bedside ultrasound (FAST exam) in the emergency department to look quickly for fluid around the heart.
5. CT of the chest for associated injuries; cardiac MRI or coronary angiography in selected cases.

A sternal fracture on its own does not predict cardiac injury, but it signals a significant blow and prompts screening.

Treatment

Monitoring

Patients with an abnormal ECG or troponin are admitted for continuous cardiac monitoring, typically for 24 to 48 hours, because most dangerous arrhythmias appear in that window.

Treating complications

• Arrhythmias: correction of potassium and magnesium, antiarrhythmic medicines, electrical cardioversion, or temporary pacing for heart block.
• Pump failure: careful fluid management, medicines to support the heart, and sometimes mechanical support.
• Tamponade: urgent drainage of blood from around the heart (pericardiocentesis) or surgery.
• Valve, septal or wall rupture: surgical repair.
• Coronary injury: angiography and stenting where appropriate.

Anticoagulants are used cautiously in trauma patients because of bleeding risk.

Pain control and breathing

Good pain relief for associated rib and sternal fractures helps breathing and prevents pneumonia.

Complications and outlook

Most cardiac contusions recover fully within weeks. Possible complications include persistent arrhythmias, heart failure, ventricular aneurysm formation, pericarditis and delayed rupture, which is rare. Outcomes are mainly determined by associated injuries. Athletes are usually advised to avoid strenuous exercise until follow-up tests are normal.

Frequently asked questions

What is a cardiac contusion?

A cardiac contusion is a bruise of the heart muscle caused by blunt trauma to the chest, such as a car crash or fall. Bleeding and swelling within the muscle can disturb the heart's rhythm and pumping. Doctors now describe it as part of blunt cardiac injury.

What are the symptoms of a bruised heart?

Symptoms include chest pain, palpitations, a fast or irregular heartbeat, breathlessness, dizziness and, in severe cases, low blood pressure. Many people have no specific heart symptoms, so an ECG and troponin test are done after significant chest trauma.

How does a heart get bruised?

A heart is bruised when blunt force compresses it between the breastbone and spine, or when sudden deceleration jolts it inside the chest. Car crashes, falls from height, crush injuries, assaults, contact sports and sometimes CPR are common causes.

How is a cardiac contusion diagnosed?

Doctors start with an ECG and a troponin blood test. If both are normal, significant heart injury is very unlikely. If either is abnormal, the patient is monitored and has an echocardiogram to look for weak heart muscle, valve damage or fluid around the heart.

Can a cardiac contusion cause heart failure?

Occasionally. A large contusion can weaken the heart's pumping, especially the right ventricle, and valve injury can cause sudden heart failure. Most contusions are small and do not, but people with reduced function on an echocardiogram need follow-up.