Basics
Description
Cardiac trauma is direct injury to the heart as the result of a violent injury. Injury can be classified as penetrating or nonpenetrating. This discussion will be limited to nonpenetrating injury.
- Nonpenetrating injury may involve:
- Contusion of myocardium
- Laceration of any cardiac structure
- Septal perforation
- Pericarditis
- Postpericardiotomy syndrome
- Pericardial laceration
- Hemorrhage with tamponade
- Cardiac herniation
- Rupture of a papillary muscle
- Rupture of chordae tendineae
- Rupture of atrioventricular and semilunar valves
- Coronary artery thrombosis
- Great vessel injury
- Electrical/rhythm disturbances
- Commotio cordis
Epidemiology
- In persons <40, violent or traumatic injury accounts for majority of deaths in the U.S.
- Injury is frequently secondary to a motor vehicle accident, fall, work related (eg, using heavy machinery), or as a result of acts of violence.
Incidence
Cardiac trauma accounts for 30-50% of 150,000 total annual deaths from trauma.
Risk Factors
- Young adult males are the most common sufferers of cardiac trauma because they are most likely to be involved in acts of violence.
- Predominant age: Young more affected than elderly.
- Predominant sex: Male > Female
General Prevention
Practical measures include protection during contact sports, seat belts while driving, and enforcing safety regulations in high-risk occupations.
Pathophysiology
- Direct force against the chest, either unidirectional or multidirectional, compresses the heart between the sternum and spine.
- Indirect forces produce increased intravascular hydrostatic pressure and predispose to rupture of fluid-filled cavities.
Etiology
- Deceleration forces, blast forces, and fractures of the ribs or sternum may lead to cardiac trauma.
- Commotio cordis refers to a fatal cardiac arrest without detectable structural cardiac damage as a result of blunt thoracic trauma during a period of electrical susceptibility. Ventricular fibrillation, among other mechanisms, has been postulated as the etiology.
Associated Conditions
Trauma to other parts of the body often influences surgical decisions and prognosis.
Diagnosis
History
- Recent blunt trauma to the chest wall, including vehicular impact, either directly or indirectly
- Direct blows to the chest wall, direct cardiac compression (eg, during cardiopulmonary resuscitation, kicks from animals, falls)
- Chest pain that is often similar to that of acute coronary syndromes, frequently precordial, and may have a pleuritic component
- Pain may be difficult to assess secondary to simultaneous musculoskeletal trauma, such as rib fractures.
Physical Exam
- Presentation can range from asymptomatic to cardiogenic shock with rapid progression to death.
- CHF, which may manifest acutely or over several days
- Hypovolemia, which may present as hypotension and tachycardia
- Pericardial involvement: Hypotension, oliguria, anuria, distant heart sounds, elevated jugular venous pressure, pulsus paradoxus, pericardial friction rub, narrow pulse pressure
- Myocardial contusion: Chest wall tenderness or traumatic lesions
- Other: Holosystolic murmur, which may represent mitral regurgitation or ventricular septal defect, 3rd heart sound (S3), rales
- EKG with nonspecific ST-T wave changes or classic findings of pericarditis; ST elevation in coronary thrombosis; pathologic Q waves may represent deep myocardial injury, conduction disorders, arrhythmias, most commonly sinus tachycardia or atrial fibrillation.
- CXR: May show an enlarged cardiac silhouette with pericardial effusion; evidence of CHF, pericardial tears with visceral herniation; may reveal air bubbles in the pericardium
Tests
Lab
Lab
- Serum enzymes: Creatinine kinase ( CK) and CK-MB fraction are elevated in patients with blunt cardiac trauma, but this is often related to skeletal muscle damage.
- Troponin I and T are more specific cardiac markers and may increase the sensitivity in detecting myocardial damage.
LabFollowup
Serial cardiac markers should be routinely drawn in patients admitted to the hospital with cardiac contusion or trauma.
Imaging
- Radionuclide imaging: Technetium pyrophosphate scan can label infarcted myocardium and can be useful in the diagnosis of myocardial necrosis:
- Not sufficiently sensitive to identify nontransmural and RV damage
- Echo can identify contused myocardium by the appearance of increased echogenicity, wall motion abnormality, myocardial edema, and impaired systolic function:
- The most common echo finding in cardiac contusion is a wall motion abnormality, often with some chamber dilation.
- A transesophageal echo is the modality of choice if visualization of the great vessels is necessary, if patients have painful chest wall injuries, or if surface transthoracic echo (TTE) is suboptimal.
- Echo can also be useful in identifying pericardial effusions in patients with pericarditis, postpericardiotomy syndrome, and pericardial tamponade.
- Angiography can be considered if the patient has evidence of coronary artery involvement or thrombosis:
- It is useful in defining LV function and coronary artery anatomy.
InitialImagingApproach
History, physical exam, and lab tests should direct approach.
ImagingFollowup
If EKG reveals specific abnormalities, if patient clinically deteriorates, or if there is a discrepancy between clinical status and clinical data, proceed to TTE or transesophageal echo (TEE).
Surgery
- Subxiphoid pericardial window, pericardiocentesis may be required to treat tamponade, and emergent surgical consultation.
- Finding a bloody effusion may confirm the diagnosis of traumatic cardiac/great vessel rupture.
Pathological Findings
Anatomic considerations:
- Anterior RV wall is most commonly involved, followed by the anterior interventricular septum and anterior apical LV.
- May also involve the conduction system, resulting in bundle branch block
Differential Diagnosis
Differential includes acute coronary syndromes, chest wall trauma, musculoskeletal pain, pericarditis, aortic injury, and CHF
Treatment
Medication
- Cardiac contusion:
- Chest pain is best treated with analgesics; NSAIDs are not advised because they interfere with myocardial healing and may contribute to increased bleeding.
- Pericardial effusion/postpericardiotomy syndrome:
- Pericarditis generally resolves spontaneously.
- Recurrent effusions with associated fever and chest pain are classified as the postpericardiotomy syndrome.
- Usually respond to aspirin or NSAIDs, but steroids are occasionally necessary. Colchicine may be an alternative:
- Treatment with anticoagulants and thrombolytics is generally contraindicated because it can predispose to bleeding and myocardial rupture.
Additional Treatment
General Measures
- Patients with suspected cardiac trauma are usually admitted to a monitored bed or ICU if at high risk for hemodynamic instability.
- If no abnormalities are detected and patient is mildly injured or asymptomatic, the patient can be observed in the emergency room for 12 hr and then discharged if the observation period is uneventful and patient has a normal follow-up EKG.
- If the EKG reveals nonspecific ST-T wave changes, the patient should be observed for 24 hr and be assessed for serial cardiac markers.
- If EKG reveals specific abnormalities, if patient clinically deteriorates, or if there is a discrepancy between clinical status and clinical data, proceed to TTE or TEE.
- Depending on the findings, patients should be monitored or have an urgent thoracotomy.
- If the CXR is abnormal, an echo should be performed.
- If other emergent surgery is indicated requiring general anesthesia, preoperative cardiac assessment including echo should be performed.
- Intraoperative hemodynamic monitoring is prudent. Patients with marked cardiac risk or known coronary/cardiac disease should be monitored closely.
Issues for Referral
Any patient with hemodynamic instability should be referred for emergent thoracotomy.
Additional Therapies
- Physical therapy
- Referral to cardiac rehabilitation is often useful, especially in the elderly population and those patients with other comorbidities.
Surgery
- Patients with rupture of the cardiac chamber, interventricular septum, or interatrial septum require emergent surgery.
- Myocardial rupture results in sudden death in most patients: Atria involved > ventricles, right-side chambers involved > left-sided chambers.
- Intracardiac fistulas include ventriculoseptal defects (VSDs), atrial septal defects, and atrioventricular fistulas. Patients with VSDs occasionally present late with heart failure and a holosystolic murmur:
- A small defect can be treated conservatively with supportive measures and subsequent repair if necessary.
- With myocardial rupture, there are often concurrent pericardial tears:
- Tears most often occur on the left.
- Tears also may involve the diaphragmatic pericardium, anterior pericardium, or left pleuropericardium.
- Any of these sites will predispose the patient to cardiac herniation and strangulation.
In-Patient Considerations
Initial-Stabilization
- ACLS protocol. If hypotension is present, rule out other causes of hypotension due to trauma before attributing to cardiac trauma.
- Any patient with hemodynamic instability should undergo emergent thoracotomy.
- On arrival, if hemodynamically stable, the patient should give a complete history and undergo a detailed physical exam, EKG, and CXR.
Admission Criteria
Patients with suspected cardiac trauma are usually admitted to a monitored bed or ICU if at high risk for hemodynamic instability. If the EKG reveals nonspecific ST-T wave changes, the patient should be observed for 24 hr and assessed for serial cardiac markers.
IV Fluids
May be necessary if patient is hypotensive and cause of hypotension is believed to be intravascular depletion.
Nursing
- Monitoring of patient's vitals, symptoms, and level of pain
- Bed rest until diagnosis and necessary surgery completed
Discharge Criteria
If no abnormalities are detected and patient is mildly injured or asymptomatic, the patient can be observed in the emergency room for 12 hr and then discharged if the observation period is uneventful and patient has a normal follow-up EKG.
Ongoing Care
Follow-Up Recommendations
Patient Monitoring
- If patients are evaluated and discharged, they should have follow-up within a week.
- Those admitted should have follow-up geared to the severity of their injuries.
Patient Education
- Young patients with minor blunt trauma/myocardial contusion should be treated similarly to those with MI with a similar amount of myocardium at risk.
- Patients with severe injury requiring surgery should undergo a recovery similar to that of a postoperative coronary bypass patient.
- Cardiac rehabilitation is often useful, especially in the elderly population and those patients with other comorbidities.
Prognosis
- Young patients who sustain myocardial contusion have an excellent prognosis.
- Although there are similarities between cardiac necrosis caused by trauma and that caused by coronary artery disease, the pathophysiology is different.
- Patients with coronary artery disease generally have other comorbidities and are much older. Both of these considerations markedly influence outcomes.
Complications
Late complications such as arrhythmia, heart failure, aneurysm, valvular regurgitation, pericardial constriction or tamponade, late VSD, or free wall rupture have been reported but are rare.
Additional Reading
1
Cook CC, Gleason TG.
Great vessel and cardiac trauma. Surg Clin North Am. 2009;89(4):797-820. [View Abstract] 2
Elie MC.
Blunt cardiac injury. Mt Sinai J Med. 2006;73(2):542-552. [View Abstract] 3
Sybrandy KC. Diagnosing cardiac contusion: Old wisdom and new insights. Heart. 2003;89:485. [View Abstract]
Codes
ICD9
- 861.00 Unspecified injury of heart without mention of open wound into thorax
- 861.01 Contusion of heart without mention of open wound into thorax
- 861.02 Laceration of heart without penetration of heart chambers or open wound into thorax
- 861.03 Laceration of heart with penetration of heart chambers, without mention of open wound into thorax
- 861.10 Unspecified injury of heart with open wound into thorax
- 861.11 Contusion of heart with open wound into thorax
- 861.12 Laceration of heart without penetration of heart chambers, with open wound into thorax
- 861.13 Laceration of heart with penetration of heart chambers and open wound into thorax
SNOMED
- 86175003 injury of heart (disorder)
- 17414004 contusion to heart (disorder)
- 40521006 contusion to heart with open wound into thorax (disorder)
- 11229008 laceration of heart without penetration of heart chambers (disorder)
- 84338002 laceration of heart with penetration of heart chambers (disorder)
- 210064002 heart laceration with open wound into thorax, with penetration of heart chambers (disorder)
- 210063008 heart laceration with open wound into thorax, without penetration of heart chambers (disorder)
Clinical Pearls
- Following chest-wall trauma, an echo should be obtained if there is hemodynamic compromise thought to be cardiac in origin, if the EKG reveals specific abnormalities, if the patient deteriorates clinically, or if there is a discrepancy between clinical status and clinical data.
- Surgery consultation should be obtained when there is hemodynamic compromise or when the EKG reveals new structural cardiac abnormalities such as intracardiac fistulas or pericardial tears.