Dominique Musset

Diagnostic strategy for patients with suspected pulmonary embolism: a prospective multicentre outcome study

BACKGROUND We designed a prospective multicentre outcome study to evaluate a diagnostic strategy based on clinical probability, spiral CT, and venous compression ultrasonography of the legs in patients with suspected pulmonary embolism (PE). The main aim was to assess the safety of withholding anticoagulant treatment in patients with low or intermediate clinical probability of PE and negative findings on spiral CT and ultrasonography. METHODS 1041 consecutive inpatients and outpatients with suspected PE were included. Patients with negative spiral CT and ultrasonography and clinically assessed as having a low or intermediate clinical probability were left untreated. Those with high clinical probability underwent lung scanning, pulmonary angiography, or both. All patients were followed up for 3 months. FINDINGS PE was diagnosed in 360 (34.6%) patients; 55 had positive ultrasonography despite negative spiral CT. Of 601 patients with negative spiral CT and ultrasonography, 76 were clinically assessed as having a high probability of PE; lung scanning or angiography showed PE in four (5.3% [95% CI 1.5-13.1]). The remaining 525 patients were assessed as having low or intermediate clinical probability, and 507 of them were not treated. Of these patients, nine experienced venous thromboembolism during follow-up (1.8% [0.8-3.3]). The diagnostic strategy proved inconclusive in 95 (9.1%) patients, and pulmonary angiography was done in 74 (7.1%). INTERPRETATION Withholding of anticoagulant therapy is safe when the clinical probability of PE is assessed as low or intermediate and spiral CT and ultrasonography are negative.

Pulmonary Veno-Occlusive Disease Clinical, Functional, Radiologic, and Hemodynamic Characteristics and Outcome of 24 Cases Confirmed by Histology

Pulmonary veno-occlusive disease (PVOD) is defined by specific pathologic changes of the pulmonary veins. A definite diagnosis of PVOD thus requires a lung biopsy or pathologic examination of pulmonary explants or postmortem lung samples. However, lung biopsy is hazardous in patients with severe pulmonary hypertension, and there is a need for noninvasive diagnostic tools in this patient population. Patients with PVOD may be refractory to pulmonary arterial hypertension (PAH)-specific therapy and may even deteriorate with it. It is important to identify such patients as soon as possible, because they should be treated cautiously and considered for lung transplantation if eligible. High-resolution computed tomography of the chest can suggest PVOD in the setting of pulmonary hypertension when it shows nodular ground-glass opacities, septal lines, lymph node enlargement, and pleural effusion. Similarly, occult alveolar hemorrhage found on bronchoalveolar lavage in patients with pulmonary hypertension is associated with PVOD. We conducted the current study to identify additional clinical, functional, and hemodynamic characteristics of PVOD. We retrospectively reviewed 48 cases of severe pulmonary hypertension: 24 patients with histologic evidence of PVOD and 24 randomly selected patients with idiopathic, familial, or anorexigen-associated PAH and no evidence of PVOD after meticulous lung pathologic evaluation. We compared clinical and radiologic findings, pulmonary function, and hemodynamics at presentation, as well as outcomes after the initiation of PAH therapy in both groups. Compared to PAH, PVOD was characterized by a higher male:female ratio and higher tobacco exposure (p < 0.01). Clinical presentation was similar except for a lower body mass index (p < 0.02) in patients with PVOD. At baseline, PVOD patients had significantly lower partial pressure of arterial oxygen (PaO2), diffusing lung capacity of carbon monoxide/alveolar volume (DLCO/VA), and oxygen saturation nadir during the 6-minute walk test (all p < 0.01). Hemodynamic parameters showed a lower mean systemic arterial pressure (p < 0.01) and right atrial pressure (p < 0.05), but no difference in pulmonary capillary wedge pressure. Four bone morphogenetic protein receptor II (BMPR2) mutations have been previously described in PVOD patients; in the current study we describe 2 additional cases of BMPR2 mutation in PVOD. Computed tomography of the chest revealed nodular and ground-glass opacities, septal lines, and lymph node enlargement more frequently in patients with PVOD compared with patients with PAH (all p < 0.05). Among the 16 PVOD patients who received PAH-specific therapy, 7 (43.8%) developed pulmonary edema (mostly with continuous intravenous epoprostenol, but also with oral bosentan and oral calcium channel blockers) at a median of 9 days after treatment initiation. Acute vasodilator testing with nitric oxide and clinical, functional, or hemodynamic characteristics were not predictive of the subsequent occurrence of pulmonary edema on treatment. Clinical outcomes of PVOD patients were worse than those of PAH patients. Abbreviations: BMPR2 = bone morphogenetic protein receptor II, CI = cardiac index, CT = computed tomography, DLCO = diffusing lung capacity of carbon monoxide, DLCO/VA = diffusing lung capacity of carbon monoxide/alveolar volume, FEV1 = forced expiratory volume in 1 second, HIV = human immunodeficiency virus, mPAP = mean pulmonary arterial pressure, mSAP = mean systolic arterial pressure, NO = nitric oxide, NYHA = New York Heart Association, PaCO2 = partial pressure of arterial carbon dioxide, PAH = pulmonary arterial hypertension, PaO2 = partial pressure of arterial oxygen, PCWP = pulmonary capillary wedge pressure, PVOD = pulmonary venoocclusive disease, PVRi = indexed pulmonary vascular resistance, SpO2 = pulse arterial oxygen saturation, TLC = total lung capacity, TPRi = indexed total pulmonary resistance, VC = vital capacity.

Management in intractable obstetric haemorrhage: an audit study on 61 cases.

OBJECTIVE To refine the indications of bilateral hypogastric artery ligation (BHAL) and angiographic selective embolisation (ASE) in intractable obstetric haemorrhage. DESIGN an audit study. SETTING Tertiary care university hospital. POPULATION AND METHODS Retrospective analysis of 61 cases of obstetric intractable post partum haemorrhage (PPH) initially managed either by hysterectomy or a conservative approach in a tertiary referral centre between 1983 and 1998. Procedures were reviewed as a primary (P) or secondary (S) attempt to arrest the haemorrhagic process. RESULTS Ten hysterectomies (5 P, 5 S), 49 BHAL (48 P, 1 S) and 9 ASE (8 P, 1S) were successfully performed in arresting the haemorrhagic process. There were 7 maternal deaths, 5 following hysterectomy and 2 following a conservative approach. Atony of the uterus was the main cause of haemorrhage (n=21) and genital tract laceration was associated with the worst prognosis. Time-elapse between delivery and surgery appears to be the main prognostic factor. Nine patients became pregnant 1 to 4 years later following a conservative approach. CONCLUSIONS ASE seems to be indicated in haemodynamically stable patients with birth canal trauma or uterine atony and clotting anomalies. BHAL is indicated when haemorrhage occurs after a cesarean section or when the patient is haemodynamically unstable. BHAL should be taught to Junior doctors in an attempt to decrease the number of patients transferred in tertiary referral centers for intractable PPH. This might also decrease the number of hysterectomies in intractable PPH.

Role of CT in chronic pulmonary embolism: comparison with pulmonary angiography.

To assess the value of CT in chronic pulmonary embolism (CPE), CT scans and pulmonary angiograms of 21 consecutive patients were reviewed. Computed tomography was better than angiography in assessing proximal clots (three thrombi not seen by angiography, three angiographic false-positives confirmed by surgery). Furthermore, CT was able to analyze pulmonary arteries distal to angiographic amputations. Computed tomography was less sensitive than angiography for vascular distortions (38 vs. 50%) and stenosis (35 vs. 71.8%). Pulmonary infarctions were better detected and characterized by CT than by angiography. Isolated parenchymal ground-glass opacities were seen by CT in 18 patients, especially in those with right cardiomegaly. High resolution CT delineated them better than did standard CT. Computed tomography may be a useful adjunct to angiography in the assessment of CPE.

Quantification of elasticity changes in the myometrium during labor using Supersonic Shear Imaging: A feasibility study

Very little is known about the myometriums physiology in terms of its elasticity but shear wave elastography could be an efficient tool to better understand it. This could considerably help the prevention of difficult births, the consequences of which are tremendous for neonate morbidity and pathologies. The purpose of this paper is to show the feasibility of the in vivo monitoring of myometrial stiffness changes in contraction and relaxation during pregnancy. In this study, Supersonic Shear Wave Imaging, a real-time and quantitative imaging technique that has been proven efficient for the investigation of tissue elasticity, was used to quantify the uterus shear-wave speed and stiffness in 6 patients, through the abdomen, using an 8-MHz linear ultrasound probe. Changes in shear wave speed were tracked in real time during the uterine contraction and were well correlated with the uterine pressure, which is currently considered to be a gold standard. These results open a new way to better understand the myometrium contraction during labour.

Effect of age on the performance of a diagnostic strategy based on clinical probability, spiral computed tomography and venous compression ultrasonography: the ESSEP study.

As the prevalence of PE increases with age, the effect of age on the diagnostic work-up in front of a clinical suspicion of PE deserves exploration. In this retrospective analysis, we used the data from 1041 consecutive suspected PE patients. The patients were divided into three groups according to tertiles of age: under 54 years, 54 to 73 years and above 73 years. The prevalence of PE in patients with respectively low, intermediate and high pretest clinical probability was expressed within each age group. We studied the effect of age on the results observed in three main groups of patients, after performing CT scan and ultrasonography (CUS): (1) patients with inconclusive results; (2) patients with negative findings on both exams and non high pretest clinical probability; (3) patients with positive findings.The prevalence of PE increased significantly with age, in overall, as well as in patients with low or intermediate pretest clinical probability. An analysis according to the three main diagnostic groups showed that: (1) the distribution of inconclusive spiral CT or CUS examinations was not different between age groups; (2) no thromboembolic event occurred in untreated patients with low or intermediate clinical probability aged under 54 years of age, whereas 7 events were diagnosed in patients aged over 73 years (p<0.001); (3) a higher proportion of older patients had a positive result at both spiral CT and CUS examinations. The percentage of positive CT scans in the case of negative or inconclusive CUS results was not different between age groups; conversely, in the case of a negative or inconclusive CT scan, the percentage of positive CUS was higher in older patients. In conclusion, management of elderly suspected PE patients appears to be different from both the work-up and the outcome perspectives.

CT imaging of peripheral pulmonary vessel disease

The diseases concerning the small pulmonary vessels are difficult to diagnose. Pathologic findings are rarely limited to the small vessels, and a continuum between the involvement of small and large vessels is frequent. Moreover, small vessels can be affected by various disease entities with overlapping radiologic features and a wide spectrum of clinical manifestations. Nevertheless, these various entities can be easily separated into two different groups by imaging techniques, particularly by computed tomography: obstructive and inflammatory diseases. Radiologic findings of obstructive diseases are relatively constant, dominated by the manifestation of pulmonary hypertension. In contrast, radiologic manifestations of inflammatory diseases are often florid and nonspecific. After a recall of the classification of small vessel diseases and the imaging techniques, we show the computed tomography features of the principal diseases involving the small pulmonary vessels by classifying them in these two principal groups.

Multidetector CT Scan Findings of a Right Aberrant Retroesophageal Vertebral Artery With an Anomalous Origin From a Cervical Aortic Arch

Various malformations of the aortic arch and great vessels have been reported in the literature, which reflects the complexity of their embryologic development. Most of them are of incidental finding and remain asymptomatic but can be responsible for respiratory or digestive symptoms and be associated with congenital cardiac diseases. We report the case of a patient presenting a right retroesophageal vertebral artery. This malformation was associated with multiple anomalies of the aortic arch. We report a classification of the most common aortic arch abnormalities by recalling Edwards double aortic arch model and embryologic variants. Here, we report on the rare case of a right retroesophageal vertebral artery. We assimilate this malformation to a vertebral arteria lusoria and attribute it to the lack of caudal migration of the fourth branchial arch, responsible for a left cervical aortic arch with an interruption between the right subclavian and vertebral arteries.

Intravenous digital subtraction angiography and lung imaging: compared value in the diagnosis of pulmonary embolism.

In a prospective study, 42 consecutive patients with clinically suspected pulmonary embolism underwent ventilation-perfuston (V-Q) lung Imaging and digital subtraction anglography (DSA) concurrently with selective conventional pulmonary anglography (CPA). Thirty-eight studies achieved within 24 hours were reviewed independently by two pairs of observers. The findings were compared using CPA as the gold standard. V-Q lung Imaging had a high percentage of indeterminate results, but none were false negative nor false positive. DSA had a lower percentage of indeterminate results but missed four of the 25 positive cases and erroneously affirmed the presence of pulmonary embolism In three cases. Therefore, the authors think that V-Q lung imaging should remain the screening examination of choice for evaluating patients with suspected pulmonary embollsm.

Shear wave elastography in obstetrics: Quantification of cervix elasticity and uterine contraction

Supersonic Shear Imaging (SSI) is a real-time and quantitative imaging technique that has been proved efficient for tissue elasticity investigation. Very little is known about the physiology of cervix and uterus and SSI could be an efficient tool for a deeper understanding of uterine mechanisms. This could considerably help prevention of premature birth, which consequences on neonate morbidity and pathologies are tremendous. The purpose of this paper is to investigate in vivo the elasticity of the cervix and uterus during pregnancy using SSI with three objectives: the quantification of cervix elasticity, the follow up of uterine elasticity during contraction, and the investigation of uterine anisotropy. In this study, remote palpation using radiation force and ultrafast imaging sequences were adapted on the Aixplorer for the investigation of uterine contraction, as well as for uterine anisotropy estimation. Cervix elasticity was quantified in 20 gravid women using a 7 MHz endocavitary probe. Uterus elasticity was quantified externally on 5 patients, through the abdomen, using an 8 MHz linear probe. Changes of elasticity were tracked in real time during uterus contraction. Shear wave tractography (imaging of fiber orientation) was performed with the same probe by assessing shear wave speed variations with respect to probe angle. This allowed the investigation of uterine anisotropy at different depths. Elasticity values during contraction were correlated to uterine pressure data, which is the gold standard for contraction monitoring. Finally, uterine fiber orientation was observed at different depths.