PubMed Health⌕ Search

Biomedical subjects

C Chauvel

Publications and source records attributed to C Chauvel.

At least 19 recordsLinked to original sources
PubMed2000

Usefulness of three-dimensional echocardiography for the evaluation of mitral valve prolapse: an intraoperative study.

BACKGROUND AND AIM OF THE STUDY: The study aim was to evaluate the feasibility of intraoperative three-dimensional (3D) transesophageal echocardiography (TEE) in patients referred for mitral valve prolapse (MVP) repair and to compare two-dimensional (2D) TEE and 3D TEE and surgical findings. METHODS: Forty-six patients (mean age 67 +/- 11 years) underwent 3D TEE intraoperatively. Measurements were made of the posterior part of mitral annulus circumference (PMAC), and the width of mitral valve surgical resection on the mitral annulus (WMVR). Using 3D TEE, MVP topography was described, and PMAC in diastole and the width of implantation of MVP on the mitral annulus (WMVP) in systole were measured. RESULTS: 3D TEE was successful in 42 patients (91%). 2D and 3DTEE correctly predicted MVP localization in 38 (90%) and 36 (86%) patients, respectively (p = NS). 3D TEE and surgical PMAC were 89 +/- 13 and 93 +/- 21 mm, respectively (p = 0.01, R = 0.42). WMVR and WMVP were 28 +/- 11 mm and 26 +/- 11 mm, respectively (p <0.0001, R = 0.82). WMVR/anatomic PMAC (0.29 +/- 0.11) and WMVP/3D echo PMAC (0.32 +/- 0.11) were correlated (p <0.0001, R= 0.69). CONCLUSION: Intraoperative 3D TEE evaluation of MVP is feasible. MVP width and its ratio to the mitral annulus were assessed, and found to correlate with surgical findings. These 3D data may be of value to the surgeon when performing mitral valve repair.

Aged↗
PubMed1998

Usefulness of pulmonary regurgitation Doppler tracings in predicting in-hospital and long-term outcome in patients with inferior wall acute myocardial infarction.

Right ventricular (RV) involvement is frequent during inferior wall acute myocardial infarction (AMI) and has been reported as a risk factor for in-hospital morbidity and mortality. The objectives of the present study were: (1) to evaluate in-hospital events in patients with and without RV involvement as diagnosed by abnormal flow characteristics derived from pulmonary regurgitation (PR) analysis (pressure half-time of PR, PHT(PR) < or = 150 ms and the lowest mid-diastolic to peak early diastolic velocity ratio, Vmin/Vmax < or = 0.5); and (2) to determine the influence of RV involvement in complications at long-term follow-up. Among 126 consecutively admitted patients with inferior wall AMI (mean age, 58 +/- 13 years), 101 had PR. We determined the prognostic significance of in-hospital and long-term events for the following variables: age > or = 65 years, ST-segment elevation > or = 1 mm in lead V4R, RV dilation, PHT of PR < or = 150 ms and Vmin/Vmax < or = 0.5, thrombolytic therapy, 3-vessel disease, and diabetes mellitus. We found that the PR derived Doppler index (PHT of PR < or = 150 ms and Vmin/Vmax < or = 0.5) was the only predictor of overall in-hospital clinical events (hazards ratio, 2.7, 95% confidence interval, 1.2 to 6.1, p = 0.016). At long-term follow-up (mean: 20 +/- 12 months, range 12 to 69), event-free survival analysis showed that age > or = 65 years was the only predictor of any event (relative risk, 3.7, 95% confidence interval, 2.1 to 6.3, p < 0.0001). Thus, RV involvement diagnosed with the use of PR flow-derived variables is an accurate and independent predictor of in-hospital complications. However, RV involvement does not influence long-term prognosis.

Aged↗
PubMed1998

Systematic ultrasonography in asymptomatic dense breasts.

The purpose of this study was to evaluate the role of ultrasonography in breast cancer screening. 350 Bilateral ultrasound (US) were performed in 350 asymptomatic patients with dense breasts. 7.5, 10 And 13 MHz transducers were used (Esaote Biomedica, Italy). In 185/350 patients, sonograms were normal, abnormalities were seen in 165/350: cysts (117), solid nodules (44) and mixed echogenicity nodules (4). All but two solid lesions were benign. Both malignant lesions were invasive carcinomas, 18 and 11 mm in diameter. In retrospect, they were palpable, but not visible on mammograms. Retroprospective review revealed that 24.7 of cysts and 31% solid nodules could be seen on mammograms. In 4 patients with fibroadenomas, US made a false positive diagnosis of breast cancer. Follow-up was obtained for 6 to 18 months in 45% of patients. Routine supplemental US evaluation for patients with mammographically dense breasts does not appear to significantly contribute to the accuracy of the work-up.

Breast Neoplasms↗
PubMed1998

Effects of a selective A1-adenosine receptor agonist on heart rate and heart rate variability during permanent atrial fibrillation.

BACKGROUND: Mean heart rate and irregularity of the rate, i.e., heart rate variability (HRV), are two aspects of heart rate during atrial fibrillation (AF). An important goal of AF therapy is to control mean heart rate during exercise; the determinants of HRV during AF remain poorly known although its prognostic value has been established. OBJECTIVES: To investigate the effects of a stable, long-acting, selective A1-adenosine receptor agonist, SDZ WAG994, on heart rate during exercise and on HRV. METHODS: In a multicenter, double-blind, randomized, placebo-controlled, parallel group study, patients with permanent AF performed a symptom-limited exercise test and underwent 24-hour ECG monitoring on day 1 during treatment with placebo, and on day 2 during treatment with either placebo or 2 mg SDZWAG994 orally. Changes in mean heart rate during exercise and changes in HRV indices between day 1 and day 2 were compared between the two groups. RESULTS: Thirty-two patients (64 +/- 8 years; 81% male; 25% in NYHA Class II; 38% with no structural heart disease) were included in the study. During active treatments, heart rate remained unchanged at rest and increased significantly during exercise. A significant daytime increase in short-term HRV indices (DpNN50 = 4.5% P = 0.01; DrMSSD = 6% P = 0.03; DSDNN Index = 6% P = 0.02) occurred during active treatment. CONCLUSIONS: Selective A1-adenosine receptor agonism with SDZ/WAG994 limits the increase in mean heart rate during exercise in patients with AF. In addition, this agonist selectively increases short-term HRV indices, suggesting that pNN50, rMSSD, and SDNN reflect vagal influences during AF.

Adenosine↗
PubMed1997

Aortic plaque morphology and vascular events: a follow-up study in patients with ischemic stroke. FAPS Investigators. French Study of Aortic Plaques in Stroke.

BACKGROUND: Atherosclerotic disease of the aortic arch has been found to be associated with the risk of ischemic stroke. We have shown that atherosclerotic plaques > or = 4 mm in thickness in the ascending aorta and proximal arch detected by transesophageal echocardiography are a risk factor for ischemic stroke. The purpose of this study was to evaluate the impact, if any, of plaque morphology (ulceration, hypoechoic plaques or calcification) on the risk of subsequent vascular events. METHODS AND RESULTS: We followed for a period of 2 to 4 years, a cohort of 334 patients 60 years or older who were consecutively admitted with brain infarction and who had transesophageal echocardiography. The risk of vascular events in patients with plaques in the aortic arch according to the presence of surface ulceration, calcifications, and sessile or mobile thrombus was estimated during a total of 788 person-years of follow-up. Hypoechoic plaques, calcifications, and ulceration were more frequently found in patients with plaques > or = 4 mm as compared with those with plaques < 4 mm. The presence of ulceration did not increase the relative risk of vascular events in patients with plaque > or = 4 mm (the relative risk was 4.3 [P<.001] in those with ulceration and 5.7 [P<.001]) in those without ulceration. The lack of calcification did increase the risk of vascular events in patients with plaque > or = 4 mm. The highest relative risk of events was found among the patients with noncalcified plaques (relative risk, 10.3; 95% confidence interval, 4.2 to 25.2; P<.001). The risk of events was systematically higher in patients without calcifications than in patients with calcifications regardless of what other morphological features were considered. CONCLUSIONS: In patients with brain infarction, the risk associated with aortic plaque thickness (> or = 4 mm) is markedly increased by the absence of plaque calcifications. These findings are important for the design of therapeutic trials in such patients.

Aged↗
PubMed1997

Comparison of arbutamine and exercise echocardiography in diagnosing myocardial ischemia.

Arbutamine is a new catecholamine designed for use as a pharmacologic stress agent. This study compared the sensitivity of arbutamine with symptom-limited exercise to induce echocardiographic signs of ischemia. Arbutamine was administered by a computerized closed-loop delivery system that controls the infusion rate of arbutamine toward a predefined rate of heart rate increase and maximum heart rate limit. Beta blockers were stopped > or = 48 hours before both tests. Stress was stopped for intolerable symptoms, or clinical, electrocardiographic or echocardiographic signs of ischemia (new or worsening wall motion abnormality), target heart rate (> or = 85% age predicted maximum heart rate), or plateau of heart rate response. Thirty-seven patients were entered into the study (35 arbutamine and exercise, 1 arbutamine only, 1 exercise only), of which 30 had angiographic evidence of coronary artery disease (> or = 50% lumen diameter narrowing). Rate-pressure product increased significantly in response to both stress modalities (p < 0.001) and was significantly greater with exercise (11,308 +/- 2,443) than with arbutamine (9,486 +/- 2,479, p < 0.001). The time to maximum heart rate was longer during arbutamine stress echocardiography than during exercise testing (17.3 +/- 9.4 versus 9.3 +/- 4.2 minutes, respectively, p < 0.001). There were more patients with interpretable echo data for arbutamine (82%) than for exercise (67%). Sensitivity for recognition of myocardial ischemia was 94% (95% confidence interval 70% to 100%) and 88% (95% confidence interval 62% to 98%), respectively. The most frequent adverse events during arbutamine (n = 36) were dyspnea (5.6%) and tremor (5.6%). Two arbutamine stress tests were discontinued due to arrhythmias: 1 patient had premature atrial and ventricular beats, and the other had premature atrial contractions and atrial fibrillation. Arrhythmias were well tolerated and resolved without sequelae. In conclusion, the sensitivity of arbutamine to induce echocardiographic signs of ischemia was similar to that of exercise despite a lower rate-pressure product. Arbutamine was well tolerated and provides a reliable alternative to exercise echocardiography.

Adult↗
PubMed1997

Mitral valve strands and the risk of ischemic stroke in elderly patients. The French Study of Aortic Plaques in Stroke (FAPS) Investigators.

BACKGROUND AND PURPOSE: Strands are thin and filamentous attachments on the cardiac valves shown by transesophageal echocardiography. Their nature and their potential for embolization are largely unknown. The objective was to estimate the risk of brain infarction in patients with mitral valve strands. METHODS: Using transesophageal echocardiography, we compared the frequency of strands on native mitral valves in 284 consecutive patients admitted with brain infarction and 276 control patients, all older than 60 years. In a second part, case subjects were followed up over a 2- to 4-year period, and the risk of recurrence of brain infarction was estimated in patients with and without strands. RESULTS: In the case-control study, mitral valve strands were found in 22.5% of the case patients and in 12.1% of the control subjects. In case subjects, mitral valve strands were more frequent in those with mitral valve dystrophy (52.4% versus 37.4%; P = .03). Strands were not associated with mitral valve prolapse, annular calcifications, or left atrial spontaneous echocardiographic contrast. After adjustment for age, sex, and mitral valve dystrophy, the odds ratio for ischemic stroke among patients with mitral strands was 2.2 (95% confidence interval, 1.4 to 3.6; P = .005). The frequency of strands was not different in patients with a known cause of brain infarction (24.4%) from that in patients with no other apparent cause (20.9%). During 646 per 100 person-years of follow-up, the incidence of recurrent brain infarction was 6.0 person-years in patients with strands and 4.2 in those without. In the Cox analysis, including potential confounders and poststroke treatment, mitral valve strands did not appear as independent predictors of recurrent brain infarction (relative risk, 1.3; 95% confidence interval, 0.5 to 3.0; P = .54). CONCLUSIONS: The present study shows an independent association between mitral valve strands and the risk of brain infarction. However, the lack of an increased relative risk of recurrence raises doubts about the potential causal relation with brain infarction in patients aged 60 years or older.

Aged↗
PubMed1997

Is dobutamine stress echocardiography useful for noninvasive differentiation of ischemic from idiopathic dilated cardiomyopathy?

Dobutamine stress echocardiography was performed in 56 consecutive patients, mean age: sixty-two +/- twelve years. Twenty-two patients had an idiopathic dilated cardiomyopathy (group 1) and 34 had angiographically proven ischemic dilated cardiomyopathy (group 2). Wall motion score index and left ventricular ejection fraction were determined at baseline, 5 micrograms/kg/min, peak, and ten minutes after stepwise dobutamine infusion. Worsening or no change in global wall motion score was observed in 9 group 2 patients (26%) and 1 group 1 patient (5%, P = .07). No significant difference was observed with regard to wall motion score index decrease between baseline and peak dose. Left ventricular ejection fraction increase during dobutamine infusion was comparable in both groups. Thus, an ischemic response was observed more often in the coronary artery disease group, yielding a good specificity and positive predictive value although sensitivity was low. However, left ventricular function improvement did not help to discriminate patients with or without significant CAD.

Aged↗
PubMed1997

[Clinical, echocardiographic and Doppler outcome in ischemic right ventricular dysfunction associated with inferior wall infarction].

Right ventricular involvement during inferior wall myocardial infarction does not seem to alter long-term clinical prognosis but its specific outcome has not been clearly studied. We have previously demonstrated that pulmonary regurgitant (PR) flow tracings doppler analysis allows the accurate diagnosis of RV involvement, especially when the pressure half-time of PR was < or = 150 ms and the ratio of the minimal velocity to the maximal velocity was < or = 0.5. We studied 40 patients with acute inferior wall myocardial infarction and with PR flow. Doppler echocardiography was obtained during the first day, before discharge (early control) and between 12 and 24 months follow-up (late control). Among 22 patients with RV involvement defined with PR-derived doppler parameters (RVIPR). 8 had right ventricular enlargement and/or wall motion abnormalities, observed in 6 cases at early control and in 4 at late control. Doppler analysis showed remnant RVIPR parameters in 9 patients at early control and 8 among these at late contorl, with no relation with pulmonary artery pressure or other echocardiographic parameters. No clinical, angiographic or therapeutic data predicted these distinct echocardiographic and doppler patterns and the long-term prognosis was not different. At late control, among 12 RVIPR patients which PR-derived doppler parameters were normal at early control, two patients had still RVIPR pattern at late control and described ischemic recurrence. PR flow doppler analysis is a useful tool for diagnosis and outcome evaluation of RV involvement and shows a remnant diastolic dysfunction in half of the patients with acute RV involvement.

Aged↗
PubMed1997

[Dobutamine stress echocardiography; a monocentric experience on 600 consecutive patients. Effect of age].

The increasing indications of dobutamine stress echo in the investigation of myocardial ischaemia, viability and evaluation of the prognosis of coronary artery disease has made this technique a tool of everyday clinical practice. The authors reviewed the results of 600 investigations in consecutive unselected including patients aged over 75. No significant difference was observed with respect to the causes of interruption of the test between patients aged less than 75 (521 patients) and those older than 75 (79 patients). Attaining the target theoretical maximal heart rate was the commonest reason for stopping the test (47 and 48% respectively). Ventricular arrhythmias were not more common (12 and 10% respectively). Twelve cases of ventricular tachycardia were observed, 8 of which were non-sustained; 9 led to interruption of the test. No cases of ventricular fibrillation were observed. A previous history of cardiac arrhythmias was not associated with a higher frequency of arrhythmia during the test (8% in those with a previous history, 4% in those patients without). Supraventricular arrhythmias were significantly more common in patients over 75 years of age (15 versus 8%, p = 0.046). Dobutamine stress echocardiography' is feasible in a population of unselected patients, including those over 75. Therefore, age does not represent a limitation to the extension of this investigation.

Adult↗
PubMed1996

Safety of dobutamine stress echocardiography. A 24 h Holter monitoring study.

BACKGROUND: Dobutamine-atropine stress echocardiography is an efficient method in the evaluation of patients with coronary artery disease. However, because high-dose dobutamine is potentially arrhythmogenic, the safety of this stress modality has been questioned. METHODS: We performed a 24 h Holter monitoring, before and immediately after this test, in 73 consecutive patients (60 men and 13 women), mean age 60 +/- 12 years. Twenty-eight patients had had a recent myocardial infarction, 25 had stable chronic angina, 10 chronic ischaemic cardiomyopathy and 10 idiopathic dilated cardiomyopathy. Dobutamine was progressively increased (5-40 micrograms.kg-1.min-1) and atropine was injected in 30 patients. Arrhythmias and ST-segment deviation before and after the stress test were evaluated. RESULTS: The mean peak dobutamine dose was 32 +/- 11 micrograms.kg-1.min-1. The heart rate at rest and at peak dose was, respectively, 69 +/- 16 and 110 +/- 28 beats.min-1. Side effects during the injection of dobutamine were mainly ventricular (n = 14) or atrial (n = 4) premature contractions. Three patients had non-sustained ventricular tachycardia and five had hypotension during the test. No sustained episode of supraventricular or ventricular tachycardia was observed during the study. Non-sustained supraventricular and ventricular tachycardias were detected in 8 and 21 patients before and in 11 and 16 patients after dobutamine stress echocardiography (P = ns). Asymptomatic ST-segment deviation was observed in two patients before and four after dobutamine stress echocardiography. An increase in total ischaemic time (20 vs 102 mn) was observed after the test, but only five patients had ST modifications. A separate analysis of patients with and without beta-blocker did not alter these results. In addition, when the occurrence of significant arrhythmias was stratified according to a left ventricular ejection fraction threshold of 45%, we observed no difference in frequency and severity of cardiac arrhythmias. CONCLUSION: This study demonstrates that dobutamine stress echocardiography does not significantly increase arrhythmia during the following 24 h. Further studies are required to evaluate the influence of the test on ST-segment modification during the same period.

Aged↗
PubMed1995

Hemodynamic criteria for diagnosis of right ventricular ischemia associated with inferior wall left ventricular acute myocardial infarction.

To test the diagnostic value of different hemodynamic indexes for the diagnosis of acute right ventricular (RV) ischemic dysfunction, we studied 2 groups of consecutive patients admitted for an acute left ventricular inferior wall myocardial infarction: 51 patients with (group 1) and 32 patients without (group 2) RV ischemia as determined by coronary angiography. In both groups, we analyzed by right-sided cardiac catheterization right-sided heart pressures, pulmonary capillary wedge pressure, and cardiac index. We also calculated pressure ratios (mean right atrial pressure or RV end-diastolic over pulmonary capillary wedge pressures), pulmonary vascular resistance, and RV stroke work index. We found significant differences (p < 0.01) between the 2 groups when comparing mean right atrial pressure, RV end-diastolic pressure, ratio of these 2 pressures over pulmonary capillary wedge pressure, RV stroke work index, and right atrial and RV pressure waveforms. The best combined sensitivity, specificity, positive predictive value, negative predictive value, and diagnostic accuracy were found for the right atrial M or W waveform pattern, isolated or combined with a disproportionate elevation of RV end-diastolic over pulmonary capillary wedge pressures (respectively, 92%, 94%, 90%, 87%, and 89%). Volume loading was performed in 27 patients (18 with and 9 without RV ischemia). Right heart pressures and RV stroke work index increased significantly and similarly in both groups. Cardiac index increased significantly only in patients without RV ischemia (p = 0.02). However, volume loading did not significantly modify the diagnostic value of the different hemodynamic criteria studied.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1995

Relations between Doppler tracings of pulmonary regurgitation and invasive hemodynamics in acute right ventricular infarction complicating inferior wall left ventricular infarction.

To test the hypothesis that flow characteristics from pulmonary regurgitation (PR) can predict right ventricular (RV) involvement in patients with inferior wall acute myocardial infarction, we prospectively recorded continuous-wave Doppler tracings and right-sided cardiac hemodynamics in 48 consecutive patients with inferior wall acute myocardial infarction and PR. Right heart hemodynamics enabled the identification of 29 patients with (group 1) and 19 without (group 2) RV involvement. In patients with RV involvement, the pulmonary regurgitant flow pattern was characterized by a rapid rise in flow velocity to a peak level followed by an abrupt deceleration in mid-diastole, whereas in patients without RV involvement, the deceleration in mid-diastole was gradual. The pressure half-time of PR (PHTPR) and the lowest mid-diastolic to peak early diastolic velocity ratio were significantly lower in group 1 than in group 2 (91 +/- 31 vs 214 +/- 57 ms [p < 0.001], 0.35 +/- 0.08 vs 0.59 +/- 0.13 [p < 0.001], respectively). The best diagnostic accuracy (95%) was obtained with cut-off values of PHTPR < or = 150 ms and the lowest mid-diastolic to peak early diastolic velocity ratio < or = 0.5: sensitivity 100%, specificity 89%, positive predictive value 94%, and negative predictive value 100%. Using multiple logistic regression analysis, we found that PHTPR was the strongest predictor of RV involvement. Thus, these parameters, derived from pulmonary regurgitant tracings, are useful in the noninvasive bedside diagnosis of RV infarction.

Aged↗
PubMed1995

[Segmental myocarditis in Churg-Strauss syndrome. Review of the literature apropos of a case].

We describe a 25-year old man in whom segmental myocarditis and pericarditis was diagnosed using two-dimensional echocardiography. Churg-Strauss syndrome was suspected in the presence of asthma and evidence of hypereosinophilia. Early therapy with oral prednisone led to resolution of pericarditis but septal hypokinesia was still present after 4 years. The pathophysiology of segmental myocarditis in the Churg Strauss syndrome is discussed.

Adult↗