Hervé Gastinne

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.

Diagnostic ability of hand-held echocardiography in ventilated critically ill patients

Study objectivesTo compare the diagnostic capability of recently available hand-held echocardiography (HHE) and of conventional transthoracic echocardiography (TTE) used as a gold standard in critically ill patients under mechanical ventilation.DesignA prospective and descriptive study.SettingThe general intensive care unit of a teaching hospital.PatientsAll mechanically ventilated patients requiring a TTE study with a full-feature echocardiographic platform (Sonos 5500®; Philips Medical Systems, Andover, MA, USA) also underwent an echocardiographic examination using a small battery-operated device (33 × 23 cm2, 3.5 kg) (Optigo®; Philips Medical Systems).InterventionsEach examination was performed independently by two intensivists experienced in echocardiography and was interpreted online. For each patient, the TTE videotape was reviewed by a cardiologist experienced in echocardiography and the final interpretation was used as a reference diagnosis.ResultsDuring the study period, 106 TTE procedures were performed in 103 consecutive patients (age, 59 ± 18 years; Simplified Acute Physiology Score, 46 ± 14; body mass index, 26 ± 9 kg/m2; positive end-expiratory pressure, 8 ± 4 cmH2O). The number of acoustic windows was comparable using HHE and TTE (233/318 versus 238/318, P = 0.72). HHE had a lower overall diagnostic capacity than TTE (199/251 versus 223/251 clinical questions solved, P = 0.005), mainly due to its lack of spectral Doppler capability. In contrast, diagnostic capacity based on two-dimensional imaging was comparable for both approaches (129/155 versus 135/155 clinical questions solved, P = 0.4). In addition, HHE and TTE had a similar therapeutic impact in 45 and 47 patients, respectively (44% versus 46%, P = 0.9).ConclusionsHHE appears to have a narrower diagnostic field when compared with conventional TTE, but promises to accurately identify diagnoses based on two-dimensional imaging in ventilated critically ill patients.

Comparison of Multiplane transesophageal echocardiography and contrast-enhanced helical CT in the diagnosis of blunt traumatic cardiovascular injuries

BackgroundMultiplane transesophageal echocardiography (TEE) and helical computed tomography (CT) of the chest have been validated separately against aortography for the diagnosis of acute traumatic aortic injuries (ATAI). However, their respective diagnostic accuracy in identifying blunt traumatic cardiovascular lesions has not been compared. MethodsDuring a 3-yr period, 110 consecutive patients with severe blunt chest trauma (age: 41 ± 17 yr; injury severity score: 34 ± 14) prospectively underwent TEE and chest CT as part of their initial evaluation. Results of both imaging methods were interpreted independently by experienced investigators and subsequently compared. All cases of subadventitial acute traumatic aortic injury were surgically confirmed. ResultsSeventeen patients had vascular injury and 11 had cardiac lesions. TEE and CT identified all subadventitial disruptions involving the aortic isthmus (n = 10) or the ascending aorta (n = 1) that necessitated surgical repair. In contrast, CT only depicted one disruption of the innominate artery. TEE detected injuries involving the intimal or medial layer, or both, of the aortic isthmus in four patients with apparently normal CT results who underwent successful conservative treatment. All cardiac injuries but two were identified only by TEE. ConclusionsIn patients with severe blunt chest trauma, TEE and CT have similar diagnostic accuracy for the identification of surgical acute traumatic aortic injuy. TEE also allows the diagnosis of associated cardiac injuries and is more sensitive than CT for the identification of intimal or medial lesions of the thoracic aorta.

Reactivation of Human Herpesvirus Type 6 in Multiple Organ Failure Syndrome

Human herpesvirus type 6 (HHV-6) and cytomegalovirus (CMV) are known to interact with the production of cytokines. In this study, we sought to determine the incidence of HHV-6 and CMV reactivation during multiple organ failure syndrome (MOFS) and to evaluate the potential effects of viral replication on both the morbidity and mortality associated with MOFS. Viral reactivation was assessed by use of specific polymerase chain reaction (PCR) analysis of the serum samples obtained from 48 consecutive patients with MOFS (the MOFS group) and from 48 sex- and age-matched patients with <2 organ failures (the control group). In addition, HHV-6 replication was assessed in 106 blood donors (the normal group). The incidence of HHV-6 replication was higher in the MOFS group than in the control and normal groups (26 [54%] of 48 vs. 7 [15%] of 48 and 5 [5%] of 106, respectively; P<.0001), with apparently no influence on morbidity and mortality rates. In contrast, reactivation of CMV was found in a single patient. Further studies are needed to evaluate the pathogenesis of HHV-6 replication in critically ill patients.

Routine transesophageal echocardiography for the diagnosis of aortic disruption in trauma patients without enlarged mediastinum

OBJECTIVE To assess the value of routine transesophageal echocardiography (TEE) in diagnosing traumatic disruption of the aorta (TDA) in trauma patients presenting without enlarged mediastinum on chest x-ray films. DESIGN Prospective study. MATERIALS AND METHODS TEE was routinely performed to exclude the presence of TDA in patients who sustained severe trauma secondary to abrupt deceleration collisions and presented with an upper mediastinum of fewer than 8 cm on supine chest x-ray films. Patients were divided into two groups according to the presence (group I) or absence (group II) of mediastinal hematoma diagnosed during TEE examination. Radiographic signs regarded as indicators of the presence of TDA were evaluated in both groups. RESULTS Among the 40 consecutive patients studied, TEE demonstrated two cases of TDA associated with a mediastinal hematoma that were confirmed by both aortography and surgery. One of the patients had a normal mediastinum on presentation chest x-ray films, and the other only exhibited a blurred aortic knob. Radiographic mediastinal abnormalities suggestive of TDA were observed in 13 patients, but chest x-ray films were unremarkable in 12 patients. Twenty patients had multiple rib fractures. The frequency of chest radiographic abnormalities was not significantly higher in group I (n = 6) when compared with group II patients (n = 34). TEE examination demonstrated a normal thoracic aorta in 35 patients and was nondiagnostic in 3 patients (normal aortography). CONCLUSION TEE should be routinely performed in victims of violent deceleration collisions, even in patients presenting apparently normal mediastinum on supine chest radiography.

Hand-held echocardiography with Doppler capability for the assessment of critically-ill patients: is it reliable?

ObjectiveTo evaluate the diagnostic capability of a hand-carried ultrasound device (HCU) in critically ill patients when using conventional transthoracic echocardiography (TTE) as a reference.DesignProspective, descriptive study.SettingMedical-surgical intensive care unit of a teaching hospital.PatientsAll patients requiring a TTE study were eligible.InterventionsEach patient underwent an echocardiographic examination using a full-feature echocardiographic platform (Sonos 5500, Philips Medical Systems, Andover, MA) and a small battery-operated device (SonoHeart Elite, SonoSite, Bothell, WA). The operators (level III training in echocardiography) were randomized (HCU vs. TTE) and they independently interpreted the echocardiograms at the patient bedside.ResultsDuring a 2-month period, 55 consecutive patients (age: 61±16 years, simplified acute physiology score 46±15, body mass index 26±7) were studied, 40 of them being mechanically ventilated (73%). The number of acoustic windows was comparable using HCU and TTE (2.3±0.8 vs. 2.4±0.8: P=0.24). The overall diagnostic accuracy of HCU was lower compared with conventional TTE (137/171 vs. 158/171 clinical questions solved: P=0.002), reaching 80% and 92%, respectively. Despite its spectral Doppler capability, HCU missed diagnoses that were adequately identified by TTE: elevated left ventricular pressure (n=2), relevant valvulopathy (n=2) and moderate (n=4) or severe (n=2) pulmonary hypertension. Acute management was altered by HCU and TTE findings in 27 patients (49%) and 28 patients (51%), respectively.ConclusionsIn this study, HCU had a lower diagnostic accuracy compared with conventional TTE, despite its spectral Doppler capability. Further studies are needed to validate these evolving diagnostic tools in critical care settings.

753-5 Role of Transesophageal Echocardiography in the Diagnosis and Management of Traumatic Rupture of the Aortic Isthmus

A comprehensive description of transesophageal echocardiographic (TEE) findings associated with traumatic aortic rupture (TAR) is still lacking. To correlate TEE and anatomic findings, a prospective study was conducted in 29 consecutive patients suffering from blunt chest trauma and suspected TAR. Confirmation of the diagnosis of TAR was obtained by either aortography, surgery, or necropsy in all patients. TEE studies were performed during the first day of admission using a monoplane probe. TEE studies and aortograms were reviewed by independent experienced observers. The diagnosis of subadventitial TAR was made in 9 patients and intimal tears in 2 patients (one confirmed and one missed by aortography). Subadventitial TAR appeared as an abnormal thick structure composed of intima and media, and mobile within the isthmus lumen. Color flow mapping revealed no differences in blood flow velocity on both sides of the disrupted aortic wall with turbulent flow surrounding the traumatic tear. Symmetric or asymmetric localized aortic enlargement reflecting the adventitia under tension was also noted. This type of lesion requires prompt surgical repair. In contrast. intimal aortic tears appeared as very mobile thin appendages of the aortic wall. Color flow mapping demonstrated a localized mosaic of colors reflecting blood flow turbulence around the intimal laceration, Aortic diameter remained unchanged, since the tear was too small and superficial to induce adventitial distention. Since these lesions appear to regress spontaneously, conservative management and TEE follow-up was undertaken. TEE failed to diagnose a two-millimeter long medial aortic rupture with integrity of the adventitia (demonstrated at necropsy). Aortography must be obtained when the TEE study is equivocal or when a laceration of the aortic arch and the brachiocephalic arteries is suspected. Conclusions In this study, transesophageal echocardiographic and anatomic findings in patients with traumatic aortic rupture were strongly correlated. In experienced hands, TEE can be considered as an accurate firstline imaging technique for the diagnosis and management of traumatic aortic rupture.