Traumatic rupture of the aorta

Transesophageal echocardiography in the diagnosis of diseases of the thoracic aorta: part II-atherosclerotic and traumatic diseases of the aorta

Transesophageal echocardiography (TEE) has provided an accurate new window for the evaluation of diseases of the thoracic aorta. Experience with TEE has led to an increased recognition of atherosclerosis of the thoracic aorta as a source of cerebral and systemic embolism. Certain features of aortic plaque morphology detected by TEE may prove to have prognostic and therapeutic significance. The intraoperative assessment of thoracic aortic atherosclerosis by TEE may guide modifications in surgical techniques and aortic manipulations that reduce the incidence of perioperative neurologic complications. TEE has also become a valuable tool for the diagnostic evaluation of patients with blunt chest trauma. The precise role of TEE in the management of these disorders is currently under investigation.

Use of Transesophageal Echocardiography for the Assessment of Traumatic Aortic Injuries

Acute traumatic lesions of the thoracic aorta or its branches (TLA) constitute highly lethal yet treatable injuries that are increasingly diagnosed in surviving patients. Traumatic disruptions are limited to the region of the aortic isthmus in approximately 90% of cases. Unlike aortography, usually referred as the gold standard diagnostic technique, transesophageal echocardiography (TEE) is a noninvasive imaging modality that can be rapidly performed at the patient bedside. Accordingly, TEE is being increasingly used as a first-line screening test for the evaluation of patients with suspected TLA. The TEE signs associated with TLA depend on the anatomic type of aortic disruption. After a period of validation, multiplane TEE allows accurate diagnosis of traumatic disruptions of the aortic isthmus, with a sensitivity of 88% (range, 57%-100%) and a specificity of 96% (range, 84%-100%). False-negative TEE results have been mainly attributed to lacerations of aortic branches. Accordingly, aortography must be routinely performed when a traumatic injury to brachiocephalic arteries is suspected. False-positive TEE findings have been associated with the presence of ultrasound artifacts or atherosclerotic changes that mimic TLA. Accurate determination of the depth of aortic wall tears and diagnosis of blunt cardiac injuries during the TEE study are crucial to guide patient management. The presence of TEE signs associated with imminent risk of adventitial rupture should lead to prompt surgery. The use of TEE as a first-line imaging modality simplifies the initial assessment of patients at high risk for TLA and helps guide acute management.

[Transesophageal echocardiography for diagnosis of traumatic injuries to the major intrathoracic vessels in 150 patients: the effect of the learning curve]

OBJECTIVES

To evaluate the role of transoesophageal echocardiography (TOE) in the management of patients with suspected traumatic lesions of the thoracic aorta (TLA) and its branches; to assess the influence of the learning curve on the diagnostic accuracy of TOE for the identification of TLA.

STUDY DESIGN

Retrospective study.

PATIENTS

The study included 150 patients (age: 41 +/- 17; Injury Severity Scale score: 31 +/- 17) who were admitted during a 4-year period for severe blunt chest trauma and who underwent a TOE study.

METHODS

TOE were performed with either a monoplane (n = 54) or a multiplane probe (n = 96). In all cases, TLA were confirmed by angiography, computed tomography, surgery, or necropsy. Initially performed routinely, angiography was subsequently indicated when the TOE study was inconclusive or when a disruption of supraaortic arteries was suspected. Echocardiographic studies were reviewed by an experienced reader who was unaware of the medical history and initial conclusions. To evaluate the influence of the learning curve on the diagnostic accuracy of TOE, these conclusions were compared with the initial interpretations.

RESULTS

A TLA was recognized in 25 patients out of 150 (17%), and evidenced using TOE in 22 of them. Three false negative and two false positive TOE results (needless thoracotomy) were recorded. After a learning period, the rate of inconclusive TOE studies decreased (18/150 vs 7/150: P < 0.05) and no false positive finding was recorded. The sensitivity and specificity of TOE for the diagnosis of TLA were 88 and 100%, and positive and negative predictive values were 100 and 97%, respectively.

CONCLUSIONS

TOE is an accurate imaging technique for the diagnosis of TLA located at the aortic isthmus. However aortography becomes essential when injuries of the aorta branches are suspected. A learning period is required to improve the specificity of TOE for this indication.

Five frequent polymorphisms of the PAI-1 gene: lack of association between genotypes, PAI activity, and triglyceride levels in a healthy population

The main function of plasminogen activator inhibitor type 1 (PAI-1) is to decrease fibrinolysis, which leads to fibrin accumulation. An elevated plasma PAI-1 concentration has been identified as a risk factor for the development of myocardial infarction, and an association between 1 polymorphism of the PAI-1 promoter and plasma PAI-1 levels has been described. Our aim was to identify new polymorphisms in the PAI-1 gene and to further examine the relationship between PAI-1 genotypes and circulating PAI-1 levels. We report the presence of 4 new polymorphisms that were identified by non-isotopic single-strand conformational polymorphism analysis followed by sequencing. These polymorphisms were investigated in relation to PAI-1 levels in a sample of 256 healthy men, aged 50-59 years, from France and Northern Ireland. Two G/A substitutions were detected at positions -844 and +9785. The former is in strong positive linkage disequilibrium with the previously described 4G/5G polymorphism at position -675. Two polymorphisms in the 3' untranslated region were identified. One corresponds to a T/G substitution at position +11,053 and is in negative linkage disequilibrium with the G/A substitution (+9785). The other is a 9-nucleotide insertion/deletion located between nucleotides +11,320 and +11,345 in a threefold-repeated sequence. This polymorphism is in strong positive linkage disequilibrium with the G/A substitution (+9785). The overall heterozygosity provided by the 5 PAI-1 polymorphisms (including the 4 new variants and the 4G/5G polymorphism) was .77. No significant association was found between PAI activity and genotypes; furthermore, the well known associations between PAI activity and body mass index, serum triglycerides, or insulin were homogeneous according to PAI-1 genotypes.

Chest trauma: the role of transesophageal echocardiography

Aortic and cardiac injury is commonly seen with severe chest trauma and contributes to the morbidity and mortality of automobile accidents. Transesophageal echocardiography is emerging as an important diagnostic tool for the evaluation of cardiovascular injury in the setting of acute chest trauma, and anesthesiologists should be familiar with the echocardiographic features of these traumatic lesions.

Fibrinolytic factors and the risk of myocardial infarction or sudden death in patients with angina pectoris. ECAT Study Group. European Concerted Action on Thrombosis and Disabilities

BACKGROUND

Disturbances of the fibrinolytic system that lead to decreased removal of fibrin deposits may be important risk factors for coronary thrombosis. There is as yet no consensus on the prognostic value of fibrinolytic parameters, which may be attributed in part to the choice of confounding variables controlled for.

METHODS AND RESULTS

The ECAT study is a prospective multicenter study of 3043 patients with angina pectoris followed for 2 years. Baseline measurements included 10 fibrinolytic variables. The results were analyzed in relation to the subsequent incidence of myocardial infarction or sudden coronary death. They are presented before and after adjustment for clusters of confounding variables that are markers of different mechanisms: insulin resistance (body mass index, triglyceride, and HDL cholesterol), inflammation (fibrinogen and C-reactive protein), and endothelial cell damage (von Willebrand factor). An increased incidence of events was associated with higher baseline concentrations of tissue plasminogen activator (TPA) antigen (P = .0002), plasminogen activator inhibitor-1 (PAI-1) activity (P = .02), and PAI-1 antigen (P = .001). The associations of PAI-1 activity and PAI-1 antigen with risk of events disappeared after adjustment for parameters reflecting insulin resistance but were not affected by other adjustments. TPA antigen was affected to a similar extent by adjustment for parameters reflecting insulin resistance. Inflammation, or endothelial cell damage, but the risk association disappeared only after combined adjustments.

CONCLUSIONS

The prognostic role of PAI-1 in predicting coronary events is related principally to insulin resistance, whereas that of TPA antigen could be explained only by its relationship with different mechanisms, including insulin resistance, inflammation and endothelial cell damage.

Usefulness of transthoracic and transoesophageal echocardiography in recognition and management of cardiovascular injuries after blunt chest trauma

OBJECTIVE

To assess the diagnostic potential of transthoracic and transoesophageal echocardiography for the detection of traumatic cardiovascular injuries in patients suffering from severe blunt chest trauma.

DESIGN

Prospective study over a three year period.

SETTING

A regional cardiothoracic centre.

PATIENTS

134 consecutive patients (94 M/40 F; mean age 38 (SD 14) years) suffering from severe blunt chest trauma (injury severity score 33.5 (18.2)). Most patients (89%) were victims of motor vehicle accidents.

EVALUATION

All patients underwent transthoracic and transoesophageal echocardiography within 8 h of admission. Aortography was performed in the first 20 patients and in a further five equivocal cases.

RESULTS

Transthoracic echocardiography provided suboptimal images in 83 patients, detecting three aortic ruptures, 28 pericardial effusions (one cardiac tamponade), 35 left pleural effusions, and 15 myocardial contusions. Transoesophageal echocardiography was feasible in 131 patients and detected 14 aortic ruptures (13 at the isthmus), 40 pericardial effusions, 51 left pleural effusions, 34 periaortic haematomas, 45 myocardial contusions, right atrial laceration in one patient with cardiac tamponade, one tricuspid valve rupture, and one severe mitral regurgitation caused by annular disruption. For the detection of aortic rupture transoesophageal echocardiography showed 93% sensitivity, 98% specificity, and 98% accuracy. Time to surgery was significantly shorter (30 (12) v 71 (21) min; P < 0.05) for patients operated on only on the basis of transoesophageal echocardiographic findings.

CONCLUSIONS

Transthoracic echocardiography has low diagnostic yield in severe blunt chest trauma, while transoesophageal echocardiography provides accurate diagnosis in a short time at the bedside, is inexpensive, minimally invasive, and does not interfere with other diagnostic or therapeutic procedures.

Role of transesophageal echocardiography in the diagnosis and management of traumatic aortic disruption

BACKGROUND

Traumatic disruption of the aorta (TDA) is a life-threatening injury that requires rapid diagnosis and treatment. Emergency aortography, which is the current standard diagnostic imaging modality, is invasive, time-consuming, and difficult to perform in hemodynamically unstable patients with multiple trauma. We performed transesophageal echocardiography (TEE) in patients with suspected TDA to determine the diagnostic accuracy and impact on patient management of this alternative, portable imaging modality.

METHODS AND RESULTS

Thirty-two consecutive trauma patients (mean age, 40 +/- 16 years) with suspected TDA (violent deceleration accident and mediastinum > 8 cm on admission chest x-ray) prospectively underwent a TEE examination in the emergency room. Findings during TEE were compared with those encountered during aortography, surgery, or necropsy. Two subsets of traumatic aortic injuries with distinct echocardiographic signs were observed: (1) subadventitial TDA (n = 10) and (2) traumatic intimal tears (n = 3). Eighteen patients had normal TEE confirmed by aortography. One 2-mm medial tear was missed by TEE (necropsy). The sensitivity and specificity of TEE for the diagnosis of subadventitial TDA were 91% and 100%, respectively. Patients with subadventitial TDA were taken to surgery immediately, whereas patients with intimal aortic tears were treated conservatively. Eighteen patients (mean age, 57 +/- 15 years) with confirmed acute aortic dissection involving the aortic isthmus were also included to establish the echocardiographic differential diagnostic criteria between this entity and TDA.

CONCLUSIONS

TEE should be considered the first-line imaging modality for the evaluation of trauma patients with suspected injuries of the thoracic aorta because of its portability, safety, diagnostic accuracy, and potential impact on patient management.