A rational screening and treatment strategy based on the electrocardiogram alone for suspected cardiac contusion

Accuracy of diagnostic tests in cardiac injury after blunt chest trauma: a systematic review and meta-analysis

INTRODUCTION

The diagnosis of cardiac contusion, caused by blunt chest trauma, remains a challenge due to the non-specific symptoms it causes and the lack of ideal tests to diagnose myocardial damage. A cardiac contusion can be life-threatening if not diagnosed and treated promptly. Several diagnostic tests have been used to evaluate the risk of cardiac complications, but the challenge of identifying patients with contusions nevertheless remains.

AIM OF THE STUDY

To evaluate the accuracy of diagnostic tests for detecting blunt cardiac injury (BCI) and its complications, in patients with severe chest injuries, who are assessed in an emergency department or by any front-line emergency physician.

METHODS

A targeted search strategy was performed using Ovid MEDLINE and Embase databases from 1993 up to October 2022. Data on at least one of the following diagnostic tests: electrocardiogram (ECG), serum creatinine phosphokinase-MB level (CPK-MB), echocardiography (Echo), Cardiac troponin I (cTnI) or Cardiac troponin T (cTnT). Diagnostic tests for cardiac contusion were evaluated for their accuracy in meta-analysis. Heterogeneity was assessed using the I² and the QUADAS-2 tool was used to assess bias of the studies.

RESULTS

This systematic review yielded 51 studies (n = 5,359). The weighted mean incidence of myocardial injuries after sustaining a blunt force trauma stood at 18.3% of cases. Overall weighted mean mortality among patients with blunt cardiac injury was 7.6% (1.4-36.4%). Initial ECG, cTnI, cTnT and transthoracic echocardiography TTE all showed high specificity (> 80%), but lower sensitivity (< 70%). TEE had a specificity of 72.1% (range 35.8-98.2%) and sensitivity of 86.7% (range 40-99.2%) in diagnosing cardiac contusion. CK-MB had the lowest diagnostic odds ratio of 3.598 (95% CI: 1.832-7.068). Normal ECG accompanied by normal cTnI showed a high sensitivity of 85% in ruling out cardiac injuries.

CONCLUSION

Emergency physicians face great challenges in diagnosing cardiac injuries in patients following blunt trauma. In the majority of cases, joint use of ECG and cTnI was a pragmatic and cost-effective approach to rule out cardiac injuries. In addition, TEE may be highly accurate in identifying cardiac injuries in suspected cases.

Cardiac contusions in the acute care setting: Historical background, evaluation and management

INTRODUCTION

Albeit described since 1763, cardiac contusions is still an under-recognised clinical condition in the acute care setting. This evidence-based review aims to provide an overview of the topic by focusing on etiopathogenesis, classification and clinical presentation of patients with cardiac contusions, as well as on the diagnostic work-up and therapy options available for this subset population in the acute care setting.

METHODS

A targeted research strategy was performed using PubMed, MEDLINE, Embase and Cochrane Central databases up to June 2022. The literature search was conducted using the following keywords (in Title and/or Abstract): ("cardiac" OR "heart" OR "myocardial") AND ("contusion"). All available high-quality resources written in English and containing information on epidemiology, etiopathogenesis, clinical findings, diagnosis and management of cardiac contusions were included in our research.

RESULTS

Biochemical samples of cardiac troponins together with a 12‑lead ECG appear to be sufficient screening tools in hemodynamically stable subjects, while cardiac ultrasound provides a further diagnostic clue for patients with hemodynamic instability or those more likely to have a significant cardiac contusion.

CONCLUSIONS

The management of patients with suspected cardiac contusion remains a challenge in clinical practice. For this kind of patients a comprehensive diagnostic approach and a prompt emergency response are required, taking into consideration the degree of severity and clinical impairment of associated traumatic injuries.

Blunt Cardiac Injury in the Severely Injured - A Retrospective Multicentre Study

Background

Blunt cardiac injury is a rare trauma entity. Here, we sought to evaluate the relevance and prognostic significance of blunt cardiac injury in severely injured patients.

Methods

In a retrospective multicentre study, using data collected from 47,580 patients enrolled to TraumaRegister DGU (1993-2009), characteristics of trauma, prehospital / hospital trauma management, and outcome analysis were correlated to the severity of blunt cardiac injury. The severity of cardiac injury was assessed according to the abbreviated injury score (AIS score 1-6), the revised injury severity score (RISC) allowed comparison of expected outcome with injury severity-dependent outcome. N = 1.090 had blunt cardiac trauma (AIS 1-6) (2.3% of patients).

Results

Predictors of blunt cardiac injury could be identified. Sternal fractures indicate a high risk of the presence of blunt cardiac injury (AIS 0 [control]: 3.0%; AIS 1: 19.3%; AIS 2-6: 19.1%). The overall mortality rate was 13.9%, minor cardiac injury (AIS 1) and severe cardiac injury (AIS 2-6) are associated with higher rates. Severe blunt cardiac injury (AIS 4 and AIS 5-6) is associated with a higher mortality (OR 2.79 and 4.89, respectively) as compared to the predicted average mortality (OR 2.49) of the study collective.

Conclusion

Multiple injured patients with blunt cardiac trauma are at high risk to be underestimated. Careful evaluation of trauma patients is able to predict the presence of blunt cardiac injury. The severity of blunt cardiac injury needs to be stratified according to the AIS score, as the patients’ outcome is dependent on the severity of cardiac injury.

Diagnosis, work-up and management of blunt cardiac injuries

Blunt cardiac injury has a wide spectrum of clinical presentations, some of them quite severe. Its definition varies throughout the literature. The purpose of this review is to describe the epidemiology, screening, diagnosis and management of blunt cardiac injury. Blunt cardiac injury complicates up to 30% of severe blunt force trauma. It can be classified into electrical and structural abnormalities. Screening modalities include electrocardiogram and cardiac enzymes. Serial negative electrocardiograms and troponins can safely rule out blunt cardiac injury. A transthoracic echocardiogram should be performed if persistent dysrhythmia or hypotension. All dysrhythmias should be treated. Patients with structural abnormalities rarely survive. In conclusion, blunt cardiac injury is prevalent after significant blunt trauma. The appropriate screening modalities should be employed and any abnormality to be treated.

Initial management and resuscitation of severe chest trauma

Severe chest trauma, blunt or penetrating, is responsible for up to 25% of traumatic deaths in North America. Respiratory compromise is the most frequent dramatic presentation in blunt trauma, while injuries to the heart and great vessels pose the greatest risk of immediate death following penetrating trauma. More than 80% of patients will be managed with interventions that can be performed in the emergency department. This article reviews the presentation, diagnosis, and management of the most important thoracic injuries. A structured approach to the acutely unstable patient is proposed to guide resuscitation decisions.

Blunt cardiac injury in trauma patients with thoracic aortic injury

Trauma patients with thoracic aortic injury (TAI) suffer blunt cardiac injury (BCI) at variable frequencies. This investigation aimed to determine the frequency of BCI in trauma patients with TAI and compare with those without TAI. All trauma patients with TAI who had admission electrocardiography (ECG) and serum creatine kinase-MB (CK-MB) from January 1999 to May 2009 were included as a study group at a level I trauma center. BCI was diagnosed if there was a positive ECG with either an elevated CK-MB or abnormal echocardiography. There were 26 patients (19 men, mean age 45.1 years, mean ISS 34.4) in the study group; 20 had evidence of BCI. Of 52 patients in the control group (38 men, mean age 46.9 years, mean ISS 38.7), eighteen had evidence of BCI. There was a significantly higher rate of BCI in trauma patients with TAI versus those without TAI (77% versus 35%, P < 0.001).

Trauma Associated with Cardiac Conduction Abnormalities: Population-Based Perspective, Mechanism and Review of Literature

OBJECTIVES

Various cardiac conduction abnormalities have been described as being a result of trauma in many case reports. The aim of this research was to look at the association between trauma (thoracic and cardiac) and conduction abnormalities in a large hospitalized population.

METHODS

Cases diagnosed with trauma and various cardiac conduction disorders were identified based on ICD-9-CM discharge diagnoses from 986 acute general hospitals across 33 states in 2001.

RESULTS

Independent of potential confounding factors, discharge for blunt cardiac injury (BCI) was associated with a threefold increased risk for cardiac conduction abnormalities (95% confidence interval 2.45-4.51) during hospitalization in 2001. Both BCI and thoracic trauma had a significant association with right bundle branch block (RBBB) in this study (OR 6.04; 95% confidence interval (CI) 3.77-9.67 and OR 1.75; 95% CI 1.38-2.23 respectively).

CONCLUSIONS

The results of this study demonstrate the impact of trauma on cardiac conduction abnormalities. This study represents an attempt to consider a mechanism of a complex traumatic cardiac event from a population-based perspective, and may improve the prognosis for patients diagnosed with cardiac or thoracic injuries.

Challenges in the diagnosis of blunt cardiac injuries

INTRODUCTION

Blunt thoracic injuries (BTIs) are directly responsible for 20-25% of all deaths, worldwide. Involvement of heart in BTIs is largely underestimated and ignored, but reasonable estimate would be around 15%. This study was planned to emphasize on clinical-presentation and diagnosis of blunt cardiac injuries (BCIs).

RESULTS

Clinical presentation of BCIs, varied from mild chest discomfort to haemodynamic shock secondary to rapid exsanguinations. Non-specific presentation with associated injuries diverts physician's attention and delayed appearance of clinical features makes diagnosis further difficult. Cardiac markers and ECG are not specific, but high sensitivity of 100% could be reached using combination of elevated cardiactroponin levels and alterations in ECG. Transoesophageal or transthoracic echocardiography, angiography, intravascular ultrasound and nuclear scan have proven to detect cardiac injuries in BTIs, but lack specificity.

CONCLUSION

Patients with suspicious-ECG finding need cardiac-monitoring for at least 24 hours. Haemodynamically stable young (<55 years) subjects, without underlying cardiac diseases and with normal-ECG and cardiac marker, could be discharged safely.

Sternal fractures

Sternal fractures are relatively common and range from simple unicortical cracks to displaced fractures associated with life threatening injuries. This paper describes the relevant anatomy, biomechanics, mechanism of injury, clinical presentation, investigation, treatment and complications and also includes associated and concomitant injuries. A management flow chart including criteria for discharge from the emergency department is presented.

Pain control for sternal fracture using an ultrasound-guided hematoma block

In this case report, an ultrasound-guided hematoma block was performed in the Emergency Department (ED) for immediate and effective pain control in a patient suffering from a sternal fracture. This technique of anesthesia may allow safer and more effective analgesia and a more rapid discharge from the hospital or ED in selected cases.

Diagnostic Dilemmas and Current Controversies in Blunt Chest Trauma

Blunt chest injuries are common encounters in the emergency department. Instead of a comprehensive review of the management of all chest injuries, this review focuses on injuries that can be difficult to diagnose and manage, including blunt aortic injury, cardiac contusion, and blunt diaphragmatic injury. This review also discusses some recent controversies in the literature regarding the use of prophylactic antibiotics for tube thoracostomy and the optimal management of occult pneumothorax. The article concludes with a discussion of the management of rib fractures in the elderly.

The American Journal of Surgery

For the past 18 months we have been carrying the list of contents of the previous month's issue of The American Journal of Surgery, and that journal has carried our list Qf contents, In an attempt to increase awareness of each other's surgical literature, we are introducing a new venture in which we will exchange ‘digests’ on a quarterly basis. Below we publish the first such digest of The American Journal of Surgery prepared by Dr Hiram Polk, and that journal will carry a reciprocal digest of the last quarter's British Journal of Surgery prepared by our Editor, Professor John Farndon. Next month we will repeat the exercise with the German journal Der Chirurg. Comments specific to the content of individual papers in the digests should be addressed primarily to the source journal, but we would be glad to receive a copy.

Blunt cardiac injury associated with cardiac valve insufficiency: trauma links to chronic disease?

CONTEXT

Cardiac injury has been well recognised as a complication of blunt chest trauma. Its clinical spectrum ranges from blunt cardiac injury (BCI) to complete rupture of cardiac tissues, with cardiac valvular injury often being overlooked.

OBJECTIVE

To determine whether hospitalised BCI is associated with increased risk of cardiac valve insufficiency in a large multi-state hospitalised population.

METHODS

Cases with BCI and cardiac valve insufficiency were identified based on discharge diagnoses in 1997 statewide hospital discharge data from 19 states. Four valvular outcomes were studied: (1) mitral valve insufficiency, incompetence, regurgitation (MVIIR); (2) aortic valve insufficiency, incompetence, regurgitation, stenosis (AVIIRS); (3) tricuspid valve insufficiency, incompetence, regurgitation, stenosis (TVIIRS); and (4) pulmonary valve insufficiency, incompetence, regurgitation, stenosis (PVIIRS).

RESULTS

Among 1,051,081 injury discharges, 2709 (0.26%) people had BCI; 13,087 (1.25%) had MVIIR; 9811 (0.93%) had AVIIRS; 1338 (0.13%) had TVIIRS; 178 (0.02%) had PVIIRS. Independent of potential confounding factors, discharge for BCI was associated with a 12-fold increased risk for TVIIRS and a 3.4-fold increased risk for AVIIRS.

CONCLUSION

Cardiac valve insufficiency has been well recognised as an important risk factor for congestive heart failure. With the findings that BCI is associated with an increased risk of specific valvular disorders, it is possible that trauma may play an important and heretofore largely unrecognised role in a portion of the burden of cardiovascular morbidity and mortality.

Blunt cardiac injury

In summary, the incidence of BCI following blunt thoracic trauma patients has been reported between 20% and 76%, and no gold standard exists to diagnose BCI. Diagnostic tests should be limited to identify those patients who are at risk of developing cardiac complications as a result of BCI. Therapeutic interventions should be directed to treat the complications of BCI. Finally, the prognosis and outcome of BCI patients is encouraging

Diagnosing cardiac contusion: old wisdom and new insights

Cardiac contusion is usually caused by blunt chest trauma and therefore is frequently suspected in patients involved in car or motorcycle accidents. The diagnosis of a myocardial contusion is difficult because of non-specific symptoms and the lack of an ideal test to detect myocardial damage. Cardiac contusion can cause life threatening arrhythmias and cardiac failure. Many diagnostic methods, such as ECG, biochemical cardiac markers, transthoracic and transoesophageal echocardiography, and radionuclide imaging studies, have been investigated to determine their use in predicting such complications. Recently, cardiac troponin I and T were found to be highly sensitive for myocardial injury. Troponin I and T have also proved to be useful in the stratification of patients at risk for complications. Nevertheless, diagnosis of a cardiac contusion and identification of patients at risk remain a challenge. In this review the current diagnostic tests will be discussed. Also, based on these diagnostic tests, a screening strategy containing data from the latest studies is presented, with the intention of detecting patients at risk.

Chest pain in athletes

The symptom of chest pain in the athlete can represent anything from a nonspecific musculoskeletal strain to a life-threatening condition such as tension pneumothorax. For the physician charged with evaluating this patient population, a thorough knowledge of the possible etiologies, their usual diagnostic algorithms, available imaging modalities, and potential therapeutic options is essential. Although the vast majority of patients with traumatic chest pain will not harbor significant pathology, the clinician must be prepared for those few who do have such conditions, and be prepared to intervene in an appropriate, time-sensitive fashion.

Normal electrocardiography and serum troponin I levels preclude the presence of clinically significant blunt cardiac injury

BACKGROUND

Uncertainty about the definition and diagnosis of blunt cardiac injury (BCI) leads to unnecessary hospitalization and cost while trying to rule it out. The purpose of this study was to examine whether the combination of two simple tests, electrocardiography (ECG) and serum troponin I (TnI) level, may serve as reliable predictors of BCI or the absence of it.

METHODS

Over a period of 30 months (September 1999-February 2002), 333 consecutive patients with significant blunt thoracic trauma were followed prospectively. Serial ECG and TnI tests were performed routinely and echocardiography was performed selectively. Clinically significant BCI (SigBCI) was defined as the presence of cardiogenic shock, arrhythmias requiring treatment, or posttraumatic structural deficits.

RESULTS

SigBCI was diagnosed in 44 patients (13%). Of 80 patients with abnormal ECG and TnI, 27 (34%) developed SigBCI. Of 131 with normal serial ECG and TnI, none developed SigBCI. Of patients with abnormal ECG only or TnI only, 22% and 7%, respectively, developed SigBCI. The positive and negative predictive values were 29% and 98% for ECG, 21% and 94% for TnI, and 34% and 100% for the combination of ECG and TnI. The admission ECG or TnI was abnormal in 43 of 44 patients with SigBCI. Only one patient had initially normal ECG and TnI and developed abnormalities 8 hours after admission. Forty-one patients without other significant injuries stayed 1 to 3 days in the hospital only to rule out SigBCI and could have been discharged earlier. Besides ECG and TnI, other independent risk factors of SigBCI were an Injury Severity Score > 15, the presence of significant skeletal trauma, and history of cardiac disease.

CONCLUSION

The combination of normal ECG and TnI at admission and 8 hours later rules out the diagnosis of SigBCI. In the absence of other reasons for hospitalization, such patients can be safely discharged.

Acute and long-term clinical significance of myocardial contusion following blunt thoracic trauma: results of a prospective study

BACKGROUND

The clinical significance of myocardial contusion (MC) following blunt thoracic trauma is still unknown. Accordingly, in this prospective study in a regional trauma center we investigated the acute and long-term clinical significance of MC.

METHODS

One-hundred eighteen patients with manifest or suspected blunt thoracic trauma were evaluated for cardiac injury. Initial assessment was based on results of electrocardiographic, echocardiographic, and serial enzyme measurements. A follow-up (FU) assessment conducted at 3 and 12 months, respectively, was performed using electrocardiography, echocardiography, and a bicycle ergometry exercise test.

RESULTS

Of the 118 patients in the total sample, 67 (56.8%) required admission to the surgical intensive care unit (SICU) because of the severity of their noncardiac injuries. Fourteen patients of the total sample (11.8%) were diagnosed with MC and 13 of these (92.9%) belonged to the intensive care admissions, thus representing an incidence of 19.4% in this patient group. During the hospitalization period none of the patients with MC experienced acute cardiac complications. Eighty-six patients (72.0%) were assessed at FU. No new pathologies were found except in one patient. Exercise testing revealed no ECG abnormalities and none of the patients experienced limitations on the bicycle ergometer due to a cardiac cause.

CONCLUSIONS

The incidence of 19.7% of MC in our patients with blunt chest injury requiring intensive care treatment indicates that this condition is frequent in polytraumatized patients. Outcome and prognosis in patients with MC is favorable and, thus, routine cardiac work-up is not indicated. Specific diagnostic and therapeutic measures should be limited to cases where cardiac complications develop.

Use of V4R in patients who sustain blunt chest trauma

OBJECTIVE

In blunt chest trauma, the right ventricle is more vulnerable than the left. The purpose of this study was to determine whether recording V4R in patients with blunt chest trauma would provide additional useful information to that already obtained from the standard 12-lead electrocardiogram (ECG).

METHODS

Forty-five patients with blunt chest trauma and 40 unmatched control subjects without blunt chest trauma had standard 12-lead ECG and right precordial leads recorded. The ECGs were read blindly by three physicians.

RESULTS

Patients with chest trauma were distinguishable from controls on the basis of the left-sided ECGs (odds ratio, 2.9; 95% confidence interval, 1.71-4.90). This was not the case using V4R (odds ratio, 1.23; 95% confidence interval, 0.59-2.0).

CONCLUSION

Patients with a significant mechanism and physical findings of blunt chest trauma were more likely than controls to have an abnormal ECG. They were not more likely to have abnormalities in V4R. We recommend that a 12-lead ECG, but not V4R, be routinely obtained on these patients.

Clinically significant blunt cardiac trauma: role of serum troponin levels combined with electrocardiographic findings

BACKGROUND

The true importance of blunt cardiac trauma (BCT) is related to the cardiac complications arising from it. Diagnostic tests that can predict accurately if such complications will develop or not may allow early and aggressive monitoring or early discharge. We investigated the role of two simple and convenient tests, serum cardiac troponin I (cTnI) and electrocardiogram (ECG), when used to identify patients at risk of cardiac complications after BCT.

METHODS

Over a 10-month period, 115 patients with evidence of significant blunt thoracic trauma were prospectively followed to identify the presence of clinically significant BCT (Sig-BCT), defined as cardiogenic shock, arrhythmias requiring treatment, or structural cardiac abnormalities directly related to the cardiac trauma. An ECG was obtained at admission and at 8 hours. Cardiac troponin I was measured at admission, at 4 hours, and at 8 hours. Transthoracic echocardiography was performed when clinically indicated. The sensitivity, specificity, and positive and negative predictive values of ECG and cTnI to identify Sig-BCT were calculated. Clinical risk factors for Sig-BCT were examined by univariate and multivariate analysis.

RESULTS

Nineteen patients (16.5%) were diagnosed with Sig-BCT and, in 18 of them, symptoms presented within 24 hours of admission. Abnormal electrocardiographic findings were detected in 58 patients (50%) and elevated cTnI levels in 27 (23.5%). Electrocardiography and cTnI had positive predictive values of 28% and 48% and negative predictive values of 95% and 93%, respectively. However, when both tests were abnormal (positive) or normal (negative), the positive and negative predictive values increased to 62% and 100%, respectively. Other independent risk factors for Sig-BCT were head injury, spinal injury, history of preexisting cardiac disease, and a chest Abbreviated Injury Score greater than 2.

CONCLUSION

The combination of ECG and cTnI identifies reliably the presence or absence of Sig-BCT. Patients with an abnormal ECG and cTnI need close monitoring for at least 24 hours. Patients with a normal admission ECG and cTnI can be safely discharged in the absence of other injuries.

[Evaluation and treatment of cardiac injuries]

Cardiac injuries caused by a heart traumatism are not frequent but, of great importance given their high morbidity. Two different groups in terms of etiology, clinical picture, application of diagnostic techniques, treatment and prognosis can be considered. On one hand, there are cardiac injuries caused by a thoracal contusion, which provokes a contused lesion can affect the free wall, the interventricular septum, the valves, the subvalvular apparatus, the conduction system and the coronary vessels and, on the other hand, cardiac injuries caused by penetrating objects. Cardiac injury can lead to a life-threatening hemodynamic instability which mandates prompt and clear diagnostic and therapeutic approaches.

Advances in the diagnosis and treatment of thoracic trauma

With the exception of the use of ECG to screen patients for blunt cardiac injury, recent advances in the diagnosis of thoracic trauma involve new technology. Use of surgeon-performed pericardial and pleural ultrasound for the detection of tamponade or hemothorax, TEE or spiral CT to diagnose rupture of the thoracic aorta, and thoracoscopy to evaluate a hemothorax or the integrity of the left hemidiaphragm are all standard techniques in modern trauma centers. In terms of treatment, emergency center thoracotomy is performed more selectively and with the adjunct of staple closure for cardiac wounds. Pulmonotomy is used selectively to control deep lobar hemorrhage and to avoid the need for an emergent lobectomy. Finally, nonoperative management of an intimal tear of the thoracic aorta or delayed operative management of a full-thickness tear in the patient with multiple injuries, using beta-blocker-induced relative hypotension, is rapidly becoming the standard of care throughout the United States.

Evaluation of the patient with blunt chest trauma: an evidence based approach

The patient who has sustained blunt trauma to the chest can present a diagnostic challenge to the emergency physician. There are several diagnostic modalities available for treating life-threatening injuries to these patients. The authors review published studies to support the use of these tests in diagnosing injuries from blunt thoracic trauma. The article focuses chiefly on two current areas of controversy, the diagnosis of blunt aortic and blunt myocardial injury. Finally, the authors make recommendations for the use of various tests based on the available evidence.

Echocardiography in thoracic trauma

The availability of bedside ultrasonography can dramatically impact the care of patients with cardiac or aortic injuries. A focused, limited echocardiographic examination in the initial evaluation of victims with thoracic injuries can provide vital information the clinician needs to expedite the management of these patients. This article reviews the current use of transthoracic and transesophageal echocardiography in patients with thoracic trauma.

Trauma in pregnancy

Over the past 60 years, trauma has become the leading cause of morbidity and mortality in the pregnant patient. The emotional and physiological challenges of treating two patients simultaneously adds to an already stressful situation. Resuscitation of the pregnant trauma patient is discussed from the prehospital setting to disposition. Also discussed are non-invasive monitoring tools, such as tocodynanomometry and ultrasonography.

An evaluation of serum troponin T and signal-averaged electrocardiography in predicting electrocardiographic abnormalities after blunt chest trauma

OBJECTIVE

Despite multiple inquiries, there are no available tests to definitively detect blunt myocardial injury. The evaluation of patients with chest wall injuries without other indications for intensive care unit (ICU) admission has ranged from a single emergency department electrocardiogram (ECG) to 72 hours of continuous electrocardiographic monitoring. Recently, signal-averaged ECG and serum cardiac troponin T have demonstrated clinical utility in the evaluation of ischemic heart disease. The purpose of this study is to determine the ability of these diagnostic tests to predict the occurrence of significant electrocardiographic rhythm disturbances for patients with chest wall injuries and no other indication for ICU admission.

METHODS

We prospectively evaluated 71 consecutive adult patients admitted to a regional Level I trauma center with chest wall injuries not requiring ICU admission. We obtained admission signal-averaged ECG, serum troponin T level, standard ECG, and creatine phosphokinase (CPK-MB) level. Patients received continuous electrocardiographic monitoring, follow-up 12-lead electrocardiography, and serial monitoring of troponin and CPK-MB. Echocardiography was performed for patients with abnormal CPK-MB levels. Electrocardiographic events were graded as normal, abnormal but clinically insignificant, or clinically significant. Multiple stepwise logistic regression analysis was used to evaluate predictors for the development of clinically significant electrocardiographic events.

RESULTS

On admission, 17 of 71 patients (23.9%) had normal sinus rhythm; 13 (18.3%) had a clinically significant finding. For 50 patients, follow-up ECG was abnormal; for 26, the findings were clinically significant. Of 17 patients with normal initial ECGs, 7 (41%) developed a clinically significant abnormality. Six patients received intervention for ECG findings. Eleven of 71 patients (16%) had positive troponin T; 5 of 71 (7%) had positive CPK-MB; 15 of 71 (21%) had positive signal-averaged ECG; and 4 of 13 had positive echocardiograms. Initial electrocardiographic abnormalities and a troponin T level > 0.20 microg/L were the only variables found to predict clinically significant electrocardiographic events. Sensitivity and specificity of troponin T in predicting clinically significant abnormalities were 27 and 91%, respectively.

CONCLUSIONS

1. The best predictors for the development of significant electrocardiographic changes are an admission ECG abnormality and an elevated serum troponin T level. 2. Both tests have high specificity with low to moderate sensitivity. 3. Patients with normal ECGs may develop clinically significant events. 4. CPK-MB and echocardiograms continue to be poor predictors of significant electrocardiographic events.

Cardiac trauma. Diagnosis, management, and current therapy

In cardiac trauma the two main mechanisms of injury are blunt and penetrating trauma. Common cardiac effects of trauma include myocardial rupture, contusion, laceration, pericardial insult, coronary injury, valvular damage, arrhythmias, and conduction abnormalities. Hemodynamic instability can develop rapidly and pose marked risk to patient survival. An adequate level of clinical awareness and timely use of diagnostic techniques such as echocardiography, aortography, and cardiac angiography are essential for rapid identification of cardiac trauma. Once the diagnosis is made, prompt surgical intervention is often the key to survival.

Sternal fracture - regional experience

A retrospective analysis of 27 sternal fracture patients out of 267 patients with chest trauma was done in the period between March 1990 (9-1410) and April 1994 (11-1414) at Asir Central Hospital, giving an incidence of 10% in all chest trauma. There were 25 males and two females, giving a ratio of 12.5:1. The age range was 18-70, with a mean age of 37.5 years and a median age of 35 years. The mean hospital stay was 12.2 days, with a range of 3 to 53 days and a median of seven days. The mechanism of injury and the types of associated injuries are presented. Twenty-eight percent of the sternal fracture patients had abnormal electrocardiogram. Echocardiogram was done on only eight patients (32%); two were abnormal.

Cardiac enzymes are irrelevant in the patient with suspected myocardial contusion

BACKGROUND

Myocardial contusion is commonly diagnosed following blunt chest trauma, and has potentially lethal complications. Cost-effective case management in patients with suspected myocardial contusion is confounded by the low incidence of complications and the lack of a reliable test to predict them. The clinical usefulness of elevated cardiac enzyme levels is controversial.

METHODS

We analyzed a 4-year experience of 359 patients with high-risk blunt chest trauma who were assessed using an established practice guideline. Our multivariate statistical model evaluated all of the early risk factors included in the guideline, specifically focusing on cardiac enzyme levels.

RESULTS

Myocardial contusion was diagnosed in 30% of patients, and complications (dysrhythmias and cardiogenic shock) occurred in 5%. In no case was cardiac enzyme elevation the sole predictor of a complication. The cost of routine cardiac enzyme assay was substantial.

CONCLUSION

Cardiac enzyme determinations have no useful role in the evaluation of patients with suspected myocardial contusion. They should be eliminated from current practice guidelines.