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P Vignon

Publications and source records attributed to P Vignon.

At least 19 recordsLinked to original sources
PubMed2003

[Portable echocardiographs: useful or futile?].

Echocardiographic systems which are the size of a laptop computer are currently available. These hand-held ultrasound units are very easy to use at patient bedside in various clinical settings. According to the miniaturized devices, spectral Doppler may not be available and power Doppler may replace true color Doppler. Validation studies of hand-held echocardiography have been conducted in critically ill patients, in patients hospitalized in ward, but also in outpatients and as a screening tool for the detection of cardiac abnormalities in the community. Hand-held echocardiography appears to have important limitations in specific clinical settings, such as shock, pulmonary hypertension, assessment of valvulopathy or valvular prosthesis, dynamic left outflow tract obstruction, left ventricular restriction or construction. The miniaturized system with spectral Doppler capability has not yet been properly validated in these indications. At its present stage of development, hand-carried ultrasound units do not allow to perform a comprehensive examination which relies on the use of a full-feature system, especially when a precise hemodynamic evaluation is required. Diagnostic ability of hand-held echocardiography is similar to that of upper-end platforms for diagnoses based on two-dimensional imaging: left ventricular systolic function, detection of wall motion abnormalities, size of cardiac chambers, identification of pericardial or pleural effusions. Hand-carried ultrasound devices may be considered as a "visual stethoscope" which provides an extension of the physical examination, but not as a potential alternative to standard transthoracic echocardiography. Its large potential clinical field of use raises the concern of taylored training programs to intensivists which could be focused on goal-directed echocardiographic examinations.

Clinical Trials as Topic↗
PubMed2001

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.

Adolescent↗
PubMed2001

[Hemophagocytosis during multiple organ failure: M-CSF overproduction or viral reactivation?].

OBJECTIVE: This study was aimed to assess the potential role of M-CSF and viral reactivation in the genesis of haemophagocytosis during the multiple organ failure (MOF) syndrome. METHODS: Twenty-five patients (mean age: 60 +/- 16 years; Apache II: 23 +/- 5) sustaining MOF with an unexplained thrombocytopenia were studied. In each patient, a bone marrow aspirate, serum M-CSF concentration, and a virological examination (Herpes viruses) were obtained on admission. In addition, 20 patients (mean age: 57 +/- 15 years; Apache II: 24 +/- 7) with at least two organ failures but no thrombocytopenia constituted the control group. Circulating M-CSF levels and the frequency of virus reactivation were compared between groups. RESULTS: Haemophagocytosis was diagnosed in 11/25 patients (44%). No viral reactivation was found. Serum M-CSF concentrations were higher in the presence of haemophagocytosis (699 +/- 242 vs 438 +/- 157 IU.mL-1; p < 0.05). Ferritin levels were also increased in the presence of a macrophage activation (3,258 +/- 2,807 vs. 520 +/- 280 mg.L-1; p < 0.0001). In contrast, both circulating M-CSF and ferritin levels were similar between thrombocytopenic patients with no hemophagocytosis and controls. CONCLUSIONS: This study confirmed the high incidence of haemophagocytosis in critically ill patients sustaining MOF. In this setting, circulating M-CSF levels were markedly elevated, whereas no Herpes viruses reactivation was found.

Aged↗
PubMed2001

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

BACKGROUND: Multiplane 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. METHODS: During 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. RESULTS: Seventeen 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. CONCLUSIONS: In 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.

Adult↗
PubMed2001

Intrathecal baclofen after traumatic brain injury: early treatment using a new technique to prevent spasticity.

BACKGROUND: In the early course of severe head trauma, the clinical value of intrathecal administration of baclofen to reduce autonomic disorders and spasticity has not been established. METHODS: We studied four patients (Glasgow Coma Scale score 3 or 4) with autonomic disorders and spasticity who failed to respond to conventional treatment during the early course of head injury. Baclofen (25 microg/mL) was infused continuously through an intrathecal catheter inserted at patient bedside and subcutaneously tunneled. When this treatment was successful, the spinal catheter was removed and surgically replaced by another catheter connected to a subcutaneous pump. Clinical follow-up was obtained at 6 months after the head injury. RESULTS: Mean delay for the initiation of intrathecal baclofen was 25 days (range, 21 to 31 days), and optimal dose was 385 +/- 185 microg/day. In all patients, the Ashworth score was consistently reduced (3.5 +/- 0.5 vs. 4.5 +/- 0.5 for upper limbs and 2 +/- 0.5 vs. 4.5 +/- 0.5 for lower limbs), as were both the frequency and intensity of autonomic disorders. The spinal catheters were used during a mean period of 9.5 +/- 1.7 days without complications. All three survivors were equipped with a programmable pump and had a lower Ashworth score at 6 months. Autonomic disorders had disappeared in two patients and remained modest in the remaining patient. CONCLUSION: Continuous administration of baclofen via the intrathecal route using this new technique seems to reduce autonomic disorders and spasticity during the early course of severe traumatic head injury.

Adult↗
PubMed2001

Differential transesophageal echocardiographic diagnosis between linear artifacts and intraluminal flap of aortic dissection or disruption.

BACKGROUND: The relatively low specificity of transesophageal echocardiography (TEE) for the diagnosis of aortic dissection (AD) or traumatic disruption of the aorta (TDA) has been attributed to linear artifacts. We sought to determine the incidence of intra-aortic linear artifacts in a cohort of patients with suspected AD or TDA, to establish the differential TEE diagnostic criteria between these artifacts and true aortic flaps, and to evaluate their impact on TEE diagnostic accuracy. METHODS AND RESULTS: During an 8-year period, patients at high risk of AD (n = 261) or TDA (n = 90) who underwent a TEE study and had confirmed final diagnoses were studied. In an initial retrospective series, linear artifacts were observed within the ascending and descending aorta in 59 of 230 patients (26%) and 17 of 230 patients (7%), respectively. TEE findings associated with linear artifacts in the ascending aorta were as follows: displacement parallel to aortic walls; similar blood flow velocities on both sides; angle with the aortic wall > 85 degrees; and thickness > 2.5 mm. Diagnostic criteria of reverberant images in the descending aorta were as follows: displacement parallel to aortic walls, overimposition of blood flow, and similar blood flow velocities on both sides of the image. In a subsequent prospective series (n = 121), systematic use of these diagnostic criteria resulted in improved TEE specificity for the identification of true intra-aortic flaps. CONCLUSIONS: Misleading intra-aortic linear artifacts are frequently observed in patients undergoing a TEE study for suspected AD or TDA. Routine use of the herein-proposed diagnostic criteria promises to further improve TEE diagnostic accuracy in the setting of severely ill patients with potential need for prompt surgery.

Adolescent↗
PubMed2001

Extrapericardial cardiac tamponade caused by traumatic retrosternal hematoma.

Cardiac tamponade is an uncommon complication of blunt chest trauma, resulting typically from hemorrhage into the pericardial space. We report a case of hemodynamic compromise secondary to an extrapericardial compression caused by the acute formation of a retrosternal hematoma associated with a sternal fracture. The patient was involved in a violent deceleration accident. Initially, he only complained of an anterior thoracic pain, but subsequently became restless, pale, and dyspneic. A severe hypotension associated with sinus bradycardia (45 bpm) rapidly occurred. Both jugular veins became markedly turgescent, but no significant pulsus paradoxus was noted. Echocardiography disclosed a large hematoma, compressing anteriorly both the right ventricular cavity and outflow tract. Surgical evacuation of the retrosternal hematoma related to a bifocal fracture of the manubrium was followed by instantaneous hemodynamic improvement. Regional extrapericardial tamponade secondary to the acute formation of compressive retrosternal hematoma is an unusual cause of circulatory failure after severe blunt chest trauma. Since conventional clinical signs associated with typical tamponade physiology may be lacking in this setting, echocardiography is ideally suited for early recognition of this unusual condition.

Accidents, Traffic↗
PubMed2000

[Refractory shock after converting enzyme inhibitor administration. Usefulness of angiotensin II].

BACKGROUND: Angiotensin-converting enzyme (ACE) inhibitors are commonly used during the early phase after myocardial infarction but severe hypotension and shock have been described. CASE REPORT: A 42-year old woman underwent a conservative management for an anterior acute myocardial infarction, initially associated with a pulmonary edema. Two hours after the initiation of a treatment with ACE inhibitor administered orally (lisinopril, Zestril), a circulatory failure in conjunction with an acute renal insufficiency occurred. Right heart catheterization disclosed markedly decreased systemic vascular resistance in the presence of a preserved cardiac index. Repeated fluid challenges and intravenous administration of norepinephrine failed to improve the hemodynamic status. The refractoriness of shock raised the hypothesis of a dysregulation of the renin-angiotensin system, secondary to the treatment by ACE inhibitor. Accordingly, the patient was given angiotensin II intravenously (Hypertension) which markedly raised systemic vascular resistance, and result in subsequent regression of shock. The patient was discharged after an otherwise uneventful course. DISCUSSION: We reported a refractory shock to fluid challenges and norepinephrine after the first dose of ACE inhibitor during acute myocardial infarction. Regression of shock was possible only with angiotensin II.

Adult↗
PubMed2000

Platelet-activating factor acetylhydrolase and haemophagocytosis in the sepsis syndrome.

Sepsis syndrome (SS) is associated with depressed PAF acetylhydrolase, the enzyme responsible for the degradation of platelet activating factor. PAF acetylhydrolase is in a large part produced by macrophages, whose inadequate activation with haemophagocytosis is frequent in patients with SS. The aim of this study was to test the hypothesis that PAF acetylhydrolase levels could be affected in these critically ill patients, because of the large amounts produced by activated macrophages in vitro and in vivo in animal models. The levels of serum PAF acetylhydrolase were assessed in 90 SS patients, who were divided into three groups: patients with (n = 34) or without haemophagocytosis (n = 31), and patients without thrombocytopenia (n = 25) who were used as a control group. The number of organ dysfunctions was matched between patients with haemophagocytosis and controls. Normal reference values were obtained in 59 randomly selected blood donors. Circulating levels of PAF acetylhydrolase were significantly (p = 0.0001) decreased in patients with SS (57+/-3 nmol/ml/min, n = 90) when compared with healthy subjects (69+/-3 nmol/ml/min, n = 59). PAF acetylhydrolase levels were greater in the presence of a haemophagocytosis but without statistical significance (64.2+/-6.5 vs. 50.1+/-2.8:p = 0.25). Despite the fact that macrophagic activation stimulates the in vitro release of PAF acetylhydrolase, no difference was found between patients with or without haemophagocytosis. The mechanism and the role of the PAF acetylhydrolase reduction in SS patients remain to be determined.

1-Alkyl-2-acetylglycerophosphocholine Esterase↗
PubMed1999

[A rare cause of sudden death in young adults with "normal" heart: the Brugada syndrome].

BACKGROUND: Brugada syndrome is a rare condition causing sudden death in young adults due to unexpected sudden-onset ventricular fibrillation. Diagnosis is based on the presence of an ST depression in the anteroseptal territory and a right branch block. No underlying dysrhythmic condition or arrhythmogenic heart disease can be detected. CASE REPORT: A 15-year old boy with an uneventful past history experienced cardiocirculatory failure due to ventricular fibrillation during a sports competition. Cardiac arrest developed and resuscitation was initially successful but death ensued due to cerebral anoxia. Characteristic electrocardiographic signs and the presence of similar anomalies in a brother and an aunt led to the diagnosis of Brugada syndrome. DISCUSSION: Brugada syndrome is a recently discovered hereditary condition with a probably underestimated prevalence. Systematic family studies have demonstrated autosomal dominant inheritance. The characteristic electrocardiographic anomalies can be transitory and may be unmasked by sensitivization tests. The only currently effective treatment is the implantable defibrillator programmed to prevent sudden death by ventricular fibrillation.

Adolescent↗
PubMed1999

Quantitative assessment of regional right ventricular function with color kinesis.

We used color kinesis, a recent echocardiographic technique that provides regional information on the magnitude and timing of endocardial wall motion, to quantitatively assess regional right ventricular (RV) systolic and diastolic properties in 76 subjects who were divided into five groups, as follows: normal (n = 20), heart failure (n = 15), pressure/volume overload (n = 14), pressure overload (n = 12), and RV hypertrophy (n = 15). Quantitative segmental analysis of color kinesis images was used to obtain regional fractional area change (RFAC), which was displayed in the form of stacked histograms to determine patterns of endocardial wall motion. Time curves of integrated RFAC were used to objectively identify asynchrony of diastolic endocardial motion. When compared with normal subjects, patients with pressure overload or heart failure exhibited significantly decreased endocardial motion along the RV free wall. In the presence of mixed pressure/volume overload, the markedly increased ventricular septal motion compensated for decreased RV free wall motion. Diastolic endocardial wall motion was delayed in 17 of 72 segments (24%) in patients with RV pressure overload, and in 31 of 90 segments (34%) in patients with RV hypertrophy. Asynchrony of diastolic endocardial wall motion was greater in the latter group than in normal subjects (16% versus 10%: p < 0.01). Segmental analysis of color kinesis images allows quantitative assessment of regional RV systolic and diastolic properties.

Adult↗
PubMed1998

Quantitative evaluation of global and regional left ventricular diastolic function with color kinesis.

BACKGROUND: Diastolic wall motion asynchrony is a major determinant of impaired left ventricular (LV) filling in patients with concentric hypertrophy and coronary artery disease. We evaluated the ability of Color Kinesis, a new echocardiographic technique that color-encodes endocardial motion, to quantitatively assess global and regional LV filling properties. METHODS AND RESULTS: Color Kinesis images and mitral and pulmonary vein flow Doppler data were acquired in 29 patients with LV hypertrophy and 29 age-matched control subjects. In addition, Color Kinesis data were correlated to coronary angiographic findings in 15 patients with suspected coronary artery disease. Segmental analysis of Color Kinesis images was used to obtain time histograms of regional diastolic fractional area change, wherein early and late peaks (peaks 1 and 2) reflected rapid LV filling and atrial contraction, respectively. Regional mean LV filling time and filling curves were used to objectively identify diastolic endocardial motion asynchrony in patients with LV hypertrophy and coronary artery disease. None of the mitral and pulmonary vein Doppler indices differentiated patients with normalized mitral Doppler profile (n=13) from control subjects, whereas reduced peak1/peak2 ratio and prolonged mean filling time indicated augmented contribution of atrial contraction toward LV filling (P<.05). In 22 of 25 patients with LV hypertrophy and preserved systolic function and in all patients with coronary artery disease, delayed diastolic endocardial motion was observed in at least one segment. CONCLUSIONS: Analysis of Color Kinesis images provides objective assessment of global and regional LV filling properties and allows identification of both diastolic dysfunction in patients with normalized Doppler indices and wall motion asynchrony.

Adult↗
PubMed1998

Use of color kinesis for evaluation of left ventricular filling in patients with dilated cardiomyopathy and mitral regurgitation.

OBJECTIVES: We tested the feasibility of using analysis of color kinesis images to objectively assess global and regional left ventricular (LV) diastolic function in patients with dilated cardiomyopathy (DCM). In addition, the ability of this technique to track drug-induced changes on LV diastolic properties was studied. BACKGROUND: Diastolic dysfunction contributes to symptomatology in patients with DCM. The assessment of LV diastolic function using conventional Doppler echocardiography is indirect and is confounded by multiple variables. Moreover, the noninvasive evaluation of regional diastolic properties is difficult. In contrast, color kinesis directly tracks and color-encodes regional diastolic endocardial motion. METHODS: We studied 24 patients with DCM and mitral regurgitation (MR) and 24 age-matched normal subjects. Transmitral and pulmonary vein flow velocities were measured using pulsed Doppler echocardiography. Diastolic color kinesis images were used to calculate indexes of magnitude and timing of global and regional diastolic function. Diastolic asynchrony was evaluated in different subgroups of patients with DCM. The effects of drug infusions (nitroprusside and dobutamine) were also studied. RESULTS: Color kinesis indexes of global diastolic function showed significant differences between patients with DCM and normal subjects. Compared with Doppler indexes, color kinesis was less confounded by MR and was capable of differentiating between drug-induced lusitropic and vasodilator effects. Diastolic asynchrony was increased in patients with DCM and severe MR. CONCLUSIONS: Quantitative analysis of global and regional LV diastolic function in patients with DCM using color kinesis is feasible.

Adult↗
PubMed1998

[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.

Adult↗
PubMed1998

Acoustic quantification indexes of left ventricular size and function: effects of signal averaging.

BACKGROUND: The aim of this study was to evaluate the clinical utility of using signal-averaged acoustic quantification (SAAQ) waveforms for improved assessment of left ventricular (LV) size and function. METHODS AND RESULTS: Four separate protocols were performed in 47 subjects. SAAQ waveforms were used to assess alterations in LV function induced by dobutamine (15 microg/kg per minute) and esmolol (200 microg/kg per minute) in eight normal subjects. Subsequently, we analyzed SAAQ waveforms obtained in 12 patients with LV dysfunction secondary to dilated cardiomyopathy and 12 age-matched normal subjects. Finally, we developed computer software for monitoring of LV function on the basis of continuous acquisition and repeated analysis of SAAQ waveforms. We compared the interbeat variability in indexes of LV function obtained from raw AQ and SAAQ during 10 minutes of steady-state monitoring in eight patients undergoing transesophageal echocardiography. The feasibility of long-term monitoring in the intensive care setting was then studied in seven patients undergoing abdominal surgery. Our analysis tracked variations in LV function induced by dobutamine and esmolol. Significant differences in all measured indexes were found between normal subjects and patients with dilated cadiomyopathy. Signal averaging during steady-state monitoring significantly reduced the interbeat variability of all indexes (21% to 42%). In the operating room, the SAAQ monitoring system tracked hemodynamic changes in close agreement with invasive measurements. CONCLUSIONS: SAAQ allows fast and easy quantification of LV function and can track hemodynamic trends in the operating room setting.

Adrenergic beta-Agonists↗
PubMed1998

Age dependency of left atrial and left ventricular acoustic quantification waveforms for the evaluation of diastolic performance in left ventricular hypertrophy.

We evaluated diastolic performance in 50 normal subjects and 50 patients with concentric left ventricular (LV) hypertrophy. Age-dependent normal values were determined for LV and left atrial (LA) acoustic quantification parameters. Pulsed wave Doppler echocardiography was also performed on all subjects. Patients with LV hypertrophy had higher peak velocities of atrial contraction and atrial contributions to filling. The acoustic quantification waveforms revealed lower rapid filling percentage of total filling and lower peak rapid filling rates. The LA acoustic quantification analysis confirmed the dependence on active atrial emptying in the patients with LV hypertrophy. There were significant correlations with age for most of the LV and LA acoustic quantification parameters. Acoustic quantification provided confirmatory results in subjects with an abnormal relaxation or restrictive Doppler pattern. In subjects with a normal Doppler pattern, the acoustic quantification was of added diagnostic value, identifying abnormalities in 77% to 80% of the patients.

Adult↗