Background It is unclear whether fibrinogen predicts cardiovascular events independently of echocardiographic cardiovascular abnormalities and traditional risk factors., Methods We studied 2671 American Indians who pa...
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Background It is unclear whether fibrinogen predicts cardiovascular events independently of echocardiographic cardiovascular abnormalities and traditional risk factors., Methods We studied 2671 American Indians who participated in the second Strong Heart Study examination (19931995) and were observed for an average of 50 - 6 months. Participants with baseline overt coronary artery disease or. a plasma creatinine level greater than or equal ***/dL were excluded. Left ventricular hypertrophy, elevated arterial stiffness, and subnormal myocardial contractility were assessed by echocardiography. Results Prevalences of echocardiographic abnormalities and cardiovascular event rates were higher with higher fibrinogen levels. Incident cardiovascular events (n = 158) and deaths (n = 64) were more frequent in participants with elevated fibrinogen levels (>400 mg/dL) than in participants with lower fibrinogen levels, as was the prevalence of echocardiographic abnormalities (both P < .01). Incident cardiovascular fatal and nonfatal events and cardiovascular deaths were 4 and 8 times higher, respectively, in participants with both elevated fibrinogen levels and echocardiographic abnormalities than in participants with neither echocardiographic abnormalities nor elevated fibrinogen levels. However, participants with fibrinogen levels >400 mg/dL had a 2 times greater relative risk of cardiovascular events or mortality, independent of both risk factors and echocardiographic abnormalities. Conclusions in a population-based sample of adults without clinical evidence of coronary artery disease at, baseline, fibrinogen levels predicted cardiovascular events independent of traditional risk factors, left ventricular hypertrophy, elevated arterial stiffness, and subnormal myocardial. systolic function.
Background Contrast echocardiography (CE) has not gained widespread use despite numerous studies, demonstrating its efficacy in the assessment of left ventricular (LV) function. Methods We sought to determine whether ...
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Background Contrast echocardiography (CE) has not gained widespread use despite numerous studies, demonstrating its efficacy in the assessment of left ventricular (LV) function. Methods We sought to determine whether CE could be used in a high-volume echocardiography laboratory in a clinically effective and time efficient manner. We implemented a protocol with a feasibility phase and an established phase. Cost-benefit analyses were done on the basis of time use. Results During the feasibility and established phases, data on 119 and 672 patients, respectively, were obtained. After a "sonographer-driven" protocol, contrast studies represented 7% to 8% of the total number of routine transthoracic and stress studies: Stress studies accounted for only 15% of the total number of contrast studies. Obesity was the most common indication for contrast use. LV visualization indices and wall thickening assessment, as evaluated by 2 blinded readers, were significantly improved with CE compared with second harmonic imaging alone. The time to make the decision to use CE and the time taken to administer contrast decreased significantly from the feasibility phase to the established phase (8.3 +/- 5 vs 7.6 +/- 5 min, P < .01, and 13.4 +/- 10 vs 10.2 +/- 5 min, P < .001, respectively). On the basis of,time use only, a cost analysis indicated that savings were obtained at a 10-minute reduction in study time. Conclusions A "sonographer-driven" CE protocol for LV assessment is feasible in high-volume echocardiography laboratories. It is clinically effective because it significantly improves LV global and regional wall motion visualization. A "sonographer-driven" CE protocol can reduce decision and administration times substantially, thus making CE time-efficient.
Background Limited resources;managed care, and advances in technology have led to the suggestion that physicians other than cardiologists be further empowered to perform the initial cardiac evaluation in children with...
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Background Limited resources;managed care, and advances in technology have led to the suggestion that physicians other than cardiologists be further empowered to perform the initial cardiac evaluation in children with suspected heart disease. To study this strategy, we compared the management decisions of pediatricians with the recommendations of pediatric cardiologists who reviewed the records of the same patients. Methods Sixty-nine patients aged <23 years with suspected heart disease were referred by pediatricians (n = 40) on the inpatient service at Boston Medical Center, for either a cardiology consultation or echocardiography. Two pediatric cardiologists who were blinded to the management decisions and clinical outcomes later reviewed the patient records. Recommendations between the 2 pediatric cardiologist reviewers and the managing pediatricians were compared. Results Pediatricians scheduled significantly fewer cardiology follow-up visits, instituted cardiac medications significantly less often, arranged significantly fewer family meetings to review cardiac findings, and ordered significantly fewer additional cardiac procedures than the pediatric cardiologists. This result was consistent regardless of whether the pediatrician's management decisions were made on the basis of the echocardiogram results only or on the recommendations of a cardiology consultant. The 2 pediatric cardiologist reviewers agreed more often with each. other than either did with the managing pediatricians. Conclusions Pediatricians have different management styles than-pediatric cardiologists for patients with suspected cardiac disease. The effect of these differences on outcome is unknown, and further investigation is warranted.
Background In patients with heart failure, biventricular pacing (BIV) improves left ventricular (LV) performance by counteracting LV unsynchronized contraction caused by the presence of left bundle branch block (LBBB)...
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Background In patients with heart failure, biventricular pacing (BIV) improves left ventricular (LV) performance by counteracting LV unsynchronized contraction caused by the presence of left bundle branch block (LBBB). However, no data are yet available on regional long-axis function in patients with LBBB or on BIV effectiveness in improving such a function in patients with heart failure and LBBB. Methods and Results We studied with standard 2D echocardiography and tissue Doppler imaging (TDI) 21 nonischemic patients in New York Heart Association (NYHA) class III-IV, with LBBB and QRS greater than or equal to 120 ms, receiving BIV. To assess long-axis function, TDI qualitative analysis at the basal level of each LV wall was performed in M-mode color and pulsed wave Doppler modalities before and after BIV. By analysis of the interventricular septum, the inferior, posterior, lateral, and anterior walls, of 105 basal segments, the following electromechanical patterns were identified: normal (pattern I), mildly unsynchronized (pattern IIA), severely unsynchronized (pattern IIB), reversed early in systole (pattern IIIA);reversed late in systole (pattern IIIB), and reversed throughout all the systole (pattern IV). After BIV, (1) 49 (46.7%) of 105 segments showed unsynchronized contraction of the same degree as before;(2) 36 (34.3%) of 105 and 20 (19%) of 105 showed unsynchronized contraction of lesser and greater degree, respectively, than before;and (3) a preexcitation pattern was found in 1 1 (10.5%) of 105, but no segment with pattern IV was observed. According to TDI analysis, patients were divided into group 1 (10 of 21), with less severe LV asynchrony than before BIV, and group 2 (11 of 21), with no change or more severe LV asynchrony than before BIV. In group 1, (1) the LV ejection fraction increased significantly (P = .01);(2) the exercise tolerance, expressed as time and work capacity on the bicycle stress testing, increased significantly (P = .01, P = .003, resp
Background The study evaluates whether Optison used during dobutamine stress echocardiography (DSE) will improve endocardial border definition and whether this will translate to an improvement in sensitivity and speci...
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Background The study evaluates whether Optison used during dobutamine stress echocardiography (DSE) will improve endocardial border definition and whether this will translate to an improvement in sensitivity and specificity of the test in patients with poor echocardiographic windows. DSE is extremely valuable in the workup of patients with coronary artery disease. The test is limited in patients with suboptimal endocardial border visualization. Frequent studies have demonstrated improved endocardial border visualization with intravenous contrast agents at rest. Methods and Results We studied 229 patients: 112 had good rest echocardiography with no contrast and 117 had poor rest echocardiography with Optison injection during DSE. Percentage of endocardial border visualization, wall thickening, sensitivity, and specificity were compared in both groups, as was interobserver variability. Both groups were matched with respect to age, percentage of previous myocardial infarctions, resting wall motion abnormality, percentage of coronary stenosis, and number of diseased coronary arteries. Optison significantly improved endocardial border visualization, especially at peak stress. The ability to measure wall thickening was significantly higher in the contrast DSE group with suboptimal images versus the noncontrast group with optimal images (89% ability to measure wall thickening vs 71%, P = .01). This resulted in a comparable sensitivity (79% vs 71%, P = not significant [NS]), specificity (76% vs 82%, P = NS), and diagnostic accuracy (80% vs 76%, P = NS). Agreement on test interpretation was higher among 3 observers in contrast DSE versus noncontrast DSE groups (79% vs 69%, P = .01). Conclusions In patients with poor echocardiographic windows, the use of Optison during DSE improves endocardial border visualization, which translates to a comparable sensitivity and specificity to noncontrast DSE tests in patients with good echocardiographic windows.
Accurate left ventricular (LV) volume and mass estimation is a strong predictor of cardiovascular morbidity and mortality. We propose that our technique of 3D echocardiography provides an accurate quantification of LV...
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Accurate left ventricular (LV) volume and mass estimation is a strong predictor of cardiovascular morbidity and mortality. We propose that our technique of 3D echocardiography provides an accurate quantification of LV volume and mass by the reconstruction of 2D images into 3D volumes, thus avoiding the need for geometric assumptions. We compared the accuracy and variability in LV volume and mass measurement using 3D echocardiography with 2D echocardiography, using in vitro studies. Six operators measured the LV volume and mass of seven porcine hearts, using both 3D and 2D techniques. Regression analysis was used to test the accuracy of results and an ANOVA lest was used to compute variability in measurement. LV volume measurement accuracy was 9.8% (3D) and 18.4% (2D);LV mass measurement accuracy was 5% (3D) and 9.2% (2D). Variability in LV volume quantification with 3D echocardiography was %SEMinter = 13.5%, %SEMintra = 11.4%, and for 2D echocardiography was %SEMinter = 21.5%, %SEMintra, = 19.1%. We derived an equation to predict uncertainty in measurement of LV volume and mass using 3D echocardiography, the results of which agreed with our experimental results to within 13%. 3D echocardiography provided twice the accuracy for LV volume and mass measurement and half the variability for LV volume measurement as compared with 2D echocardiography.
In two-dimensional echocardiography the sonographer must synthesize multiple tomographic slices into a mental three-dimensional (3D) model of the heart. Computer graphics and virtual reality environments are ideal to ...
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In two-dimensional echocardiography the sonographer must synthesize multiple tomographic slices into a mental three-dimensional (3D) model of the heart. Computer graphics and virtual reality environments are ideal to visualize complex 3D spatial relationships. In augmented reality (AR) applications, real and virtual image data are linked, to increase the information content. In the presented AR simulator a 3D surface model of the human heart is linked with echocardiographic volume data sets. The 3D echocardiographic data sets are registered with the heart model to establish spatial and temporal congruence. The heart model, together with an animated ultrasound sector represents a reference scenario, which displays the currently selected two-dimensional echocardiographic cutting plane calculated from the volume data set. Modifications of the cutting plane within the echocardiographic data are transferred and visualized simultaneously and in real time within the reference scenario. The trainee can interactively explore the 3D heart model and the registered 3D echocardiographic data sets by an animated ultrasound probe, whose position is controlled by an electromagnetic tracking system. The tracking system is attached to a dummy transducer and placed on a plastic puppet to give a realistic impression of a two-dimensional echocardiographic examination. (C) 2000 Academic Press.
OBJECTIVES This study was done to determine whether electrocardiographic (ECG) isolated ST-segment elevation (ST up arrow) in posterior chest leads can establish the diagnosis of acute posterior infarction in patients...
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OBJECTIVES This study was done to determine whether electrocardiographic (ECG) isolated ST-segment elevation (ST up arrow) in posterior chest leads can establish the diagnosis of acute posterior infarction in patients with ischemic chest pain and to describe the clinical and echocardiographic characteristics of these patients. BACKGROUND The absence of ST up arrow on the standard 12-lead ECG in many patients with acute posterior infarction hampers the early diagnosis of these infarcts and thus may result in inadequate triage and treatment. Although 4% of all acute myocardial infarction (AMI) patients reveal the presence of isolated ST up arrow in posterior chest leads, the significance of this finding has not yet been determined. METHODS We studied 33 consecutive patients with ischemic chest pain suggestive of AMI without ST up arrow in the standard ECG who had isolated ST up arrow in posterior chest leads V-7 through V-9. All patients had echocardiographic imaging within 48 h of admission, and 20 patients underwent coronary angiography. RESULTS Acute myocardial infarction was confirmed enzymatically in all patients and on discharge ECG pathologic Q-waves appeared in leads V-7 through V-9 in 75% of the patients. On echocardiography, posterior wall-motion abnormality was visible in 97% of the patients, and 69% had evidence of mitral regurgitation (MR), which was moderate or severe in one-third of the patients. Four patients (12%), all with significant MR, had heart failure, and one died from free-wall rupture. The circumflex coronary artery was the infarct related artery in all catheterized patients. CONCLUSIONS Isolated ST up arrow in leads V-7 through V-9 identify patients with acute posterior wall myocardial infarction. Early identification of those patients is important for adequate triage and treatment of patients with ischemic chest pain without ST up arrow on standard 12-lead ECG. (J Am Coll Cardiol 1999;34:748-53) (C) 1999 by the American College of Cardiolog
OBJECTIVES This study was performed to assess the prognostic implications of myocardial contractile reserve (MCR) in patients with coronary artery disease (CAD) and left ventricular (LV) dysfunction. BACKGROUND MCR du...
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OBJECTIVES This study was performed to assess the prognostic implications of myocardial contractile reserve (MCR) in patients with coronary artery disease (CAD) and left ventricular (LV) dysfunction. BACKGROUND MCR during dobutamine stress echocardiography (DSE) identifies viable myocardium that may improve in function after revascularization. Whether revascularization influences prognosis of patients with MCR has not been determined. METHODS We performed DSE in 80 patients with CAD and LV dysfunction (ejection fraction less than or equal to 40%). Viable myocardium was defined in dysfunctional myocardial segments as enhanced thickening and contraction during low-dose dobutamine (5 to 10 mcg/kg/min). Serial prospective follow-up was obtained in all patients (mean follow-up 2.2 +/- 1.1 years). RESULTS Among 52 patients treated medically, there were 20 cardiac deaths. By multivariate analysis, the number of dysfunctional segments demonstrating MCR was the strongest predictor of survival (p < 0.03). Patients with MCR had better initial survival during medical therapy than did those without MCR, but this survival advantage was not maintained beyond three years. In contrast, survival was excellent in patients with MCR who underwent myocardial revascularization. Among 58 patients with MCR in greater than or equal to 5 myocardial segments, survival at three years was 93 +/- 6% in the 24 patients who were revascularized but only 49 +/- 15% in the 34 treated medically (p < 0.02). CONCLUSIONS Myocardial contractile reserve is a significant predictor of survival in patients with CAD and LV dysfunction undergoing medical therapy. Although patients with MCR have an initial survival advantage, this advantage is lost over the course of three years. In contrast, survival in patients with significant MCR is enhanced by revascularization. (J Am Coll Cardiol 1999;34:730-8) (C) 1999 by the American College of Cardiology.
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