Myocardial contusion refers to a bruising of the heart. It is usually due to an injury to the chest wall.
What is going on in the body?
Injuries to the chest wall can be placed into two general groups. Penetrating injuries are wounds in which the chest cavity is pierced. Two examples are knife stabbings and gunshot wounds.
Nonpenetrating injuries involve crush injuries, or compression of the chest. This type of injury is often a result of motor vehicle or motorcycle crashes or explosions.
Alone or in combination, these forces can cause a myocardial contusion.
A myocardial contusion may have the following effects:
- bleeding into the pericardial sac (the membrane that surrounds the heart), which can cause cardiac tamponade
- bleeding within the heart muscle
- abnormalities in the transmission of the electrical impulses that control the heartbeat
- congestive heart failure, a condition in which the heart's decreased pumping ability causes fluid to back up into the lungs
- damage or rupture of the heart valves
- death of areas of heart muscle
- rupture of the heart chamber walls and nearby structures
- weakening of the heart muscle
What are the causes and risks of the condition?
Motor vehicle crashes are a common cause of myocardial contusion. The injury can occur when the driver bangs into the steering wheel. Falls and crush injuries can also cause a contusion. The sudden deceleration caused by these injuries creates sudden tearing forces on the body that contribute to the damage.
What can be done to prevent the condition?
Motor vehicle crashes can not always be prevented. However, seat belts used alone or with air bags can help to prevent injury. Also, the right safety equipment should be used for other types of tasks that could result in chest injury. Driving and other potentially dangerous tasks should never be done under the influence of alcohol or drugs. Following sports safety guidelines for children, adolescents, and adults may prevent some injuries.
How is the condition diagnosed?
Diagnosis of myocardial contusion begins with a medical history and physical exam. Any chest injury, even if it appears to be minor, should be reported to the healthcare provider. Diagnosing myocardial contusion can be very difficult. Many times, problems do not appear for days or even weeks after an injury.
The healthcare provider may order these tests:
- blood tests, including serial troponin (a cardiac protein that is not normally seen in the bloodstream unless there is cardiac damage) and creatine phosphokinase, or CPK, levels
- an echocardiogram, (ultrasound of the heart), or if available, cardiac MRI to check the structure and function of the heart
- an electrocardiogram, or ECG, to look for arrhythmias and conduction problems
Long Term Effects
What are the long-term effects of the condition?
A person who survives the initial trauma may develop complications in the weeks that follow. These can include:
- arrhythmias that can be fatal if left untreated
- cardiac tamponade (collection of fluid within the sac that prevents the heart from filing and contracting)
- congestive heart failure
- pericardial effusion
- traumatic aneurysm (a tear in the aorta)
What are the risks to others?
A myocardial contusion is not contagious. It poses no risk to others.
What are the treatments for the condition?
The goal of treatment is to control the symptoms. Treatments vary depending on how the heart has been damaged. Following are some common treatments:
- medicines to correct arrhythmias
- medicines to relieve pain and inflammation
- placement of a temporary pacemaker to correct conduction problems
- a procedure to drain blood and fluid from the pericardium to relieve pressure
- surgery to repair aneurysms, or tears in the heart muscle
What are the side effects of the treatments?
All medicines may have associated side effects. Some may worsen arrhythmias and conduction problems. Surgery may cause bleeding, infection, or allergic reaction to anesthesia.
What happens after treatment for the condition?
Most people who have a myocardial contusion are able to return gradually to their normal activities after a period of bed rest.
How is the condition monitored?
A person who has a myocardial contusion will need follow-up visits to the healthcare provider because complications can appear weeks after the injury. Any new or worsening symptoms should be reported to the healthcare provider.
Merck Manual 1999
Harrison's Principles of Internal Medicine 1991
Heart Disease: A Textbook of Cardiovascular Medicine, 1980