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91.
This article reviews established as well as emerging fields in the application of transesophageal echocardiography (TEE) in the investigation of myocardial ischemia. TEE already has a well defined and established role in stress echocardiography in patients with poor transthoracic acoustic window, and in the detection of intraoperative myocardial ischemia in cardiac and noncardiac surgery. The evaluation of right ventricular ischemia and infarction and the assessment of coronary flow reserve (CFR) are relatively new fields in the application of TEE and the potential of this technique has not yet been fully evaluated. The evidence collected and reviewed in this article is still preliminary but it presupposes a significant role of TEE in the diagnosis and pathophysiological assessment of myocardial ischemia. 相似文献
92.
Oki T Fukuda N Iuchi A Tabata T Manabe K Kageji Y Sasaki M Yamada H Ito S 《Echocardiography (Mount Kisco, N.Y.)》1996,13(6):623-626
A patient of cardiac amyloidosis was found to have mid-to late diastolic retrograde flow from the left atrium (LA) to the pulmonary vein. Congo-red staining was positive for amyloid in the rectal tissue. M-mode and two-dimensional echocardiograms revealed symmetric hypertrophy and typical speckled pattern of the left ventricle (LV). The LV pressure curve showed a dip and plateau configuration during diastole, and end-diastolic pressure was 28 mmHg. In addition, the LV pressure was high at mid-diastole, surpassing the pulmonary capillary wedge pressure from mid-to late diastole. The transmitral flow velocity revealed "restrictive" pattern, and the pulmonary venous flow velocity showed retrograde flow from the LA to the pulmonary vein during mid-diastole and atrial systole. It is suggested that recording of the pulmonary venous flow velocity by transesophageal pulsed Doppler echocardiography is useful for understanding the mechanism of the development of pulmonary congestion or edema. 相似文献
93.
Hsu TL Hsiung MC Lin SL Chen CH Chen CC Wang SP Chang MS Chiang BN 《Echocardiography (Mount Kisco, N.Y.)》1992,9(1):1-7
To assess the diagnostic value of transesophageal two-dimensional echocardiography (TEE) as compared with transthoracic echocardiography (TTE), TTE and TEE were performed in eight consecutive patients (age range from 20 to 76 years, six male and two female) with clinical evidence of malignant tumors arising from the liver (n = 1), lung (n = 3), larynx (n = 1), osteogenic sarcoma (n = 1), lymphoma (n = 1), and yolk sac tumor in the anterior mediastinum (n = 1). In one case, the gastroscope could not be inserted because of tumor compression of the esophagus. Transesophageal echocardiography provided superior imaging in the detection of intracavitary metastatic lesions. In the case of right ventricular outflow tract tumor and greater vessel involvement, TTE may provide more imaging than TEE due to a blind area in this region by the transesophageal approach. In conclusion, TEE is complementary to TTE in the diagnosis of metastatic cardiac tumor. 相似文献
94.
Anne S. Chin Martin J. Willemink Aya Kino Virginia Hinostroza Anna M. Sailer Michael P. Fischbein R. Scott Mitchell Gerald J. Berry D. Craig Miller Dominik Fleischmann 《Journal of the American College of Cardiology》2018,71(24):2773-2785
Background
Limited intimal tears (LITs) of the aorta (Class 3 dissection variant) are the least common form of aortic pathology in patients presenting with acute aortic syndrome (AAS). LITs are difficult to detect on imaging and may be underappreciated.Objectives
This study sought to describe the frequency, pathology, treatment, and outcome of LITs compared with other AAS, and to demonstrate that LITs can be detected pre-operatively by contemporary imaging.Methods
The authors retrospectively reviewed 497 patients admitted for 513 AAS events at a single academic aortic center between 2003 and 2012. AAS were classified into classic dissection (AD), intramural hematoma, LIT, penetrating atherosclerotic ulcer, and rupturing thoracic aortic aneurysm. The prevalence, pertinent risk factors, and detailed imaging findings with surgical and pathological correlation of LITs are described. Management, early outcomes, and late mortality are reported.Results
Among 497 patients with AAS, the authors identified 24 LITs (4.8% of AAS) in 16 men and 8 women (17 type A, 7 type B). Patients with LITs were older than those with AD, and type A LITs had similarly dilated ascending aortas as type A AD. Three patients presented with rupture. Eleven patients underwent urgent surgical aortic replacement, and 2 patients underwent endovascular repair. Medial degeneration was present in all surgical specimens. In-hospital mortality was 4% (1 of 24), and in total, 5 patients with LIT died subsequently at 1.5 years (interquartile range [IQR]: 0.3 to 2.5 years). Computed tomography imaging detected all but 1 LIT, best visualized on volume-rendered images.Conclusions
LITs are rare acute aortic lesions within the dissection spectrum, with similar presentation, complications, and outcomes compared with AD and intramural hematoma. Awareness of this lesion allows pre-operative diagnosis using high-quality computed tomography angiography. 相似文献95.
Relation of transesophageal echocardiographic findings to subtypes of cerebral infarction in patients with atrial fibrillation 总被引:1,自引:0,他引:1
Shinokawa N Hirai T Takashima S Kameyama T Obata Y Nakagawa K Asanoi H Inoue H 《Clinical cardiology》2000,23(7):517-522
BACKGROUND: Transesophageal echocardiography (TEE) has been used to identify the potential risk for cardiogenic embolism in patients with atrial fibrillation (AF). However, ischemic stroke in patients with AF is not always attributable to embolism. Identification of the risk of embolic versus atherothrombotic stroke should lead to the optimal individualized management of patients with AF. HYPOTHESIS: The goal of the study was to determine the relation between cortical infarction and perforating infarction and TEE findings in patients with AF. METHODS: We investigated the clinical usefulness of TEE in the risk stratification of clinical subtyping of the cerebral infarctions which were divided into two territories of the cortical branch (cortical infarction due to embolism) and deep perforators (perforating infarction due to atherothrombosis). Left atrial spontaneous echo contrast, peak flow velocity in the left atrial appendage, and generalized atherosclerosis as estimated by the intima-media wall thickness of the thoracic aorta were assessed by TEE in 118 consecutive patients with either paroxysmal (n = 44) or chronic (n = 74) AF. All patients underwent either brain computed tomography or magnetic resonance imaging. RESULTS: Cortical and perforating infarction was found in 39 and 18% of patients, respectively. The grade of spontaneous echo contrast was higher in patients with than in those without cortical infarction (p < 0.05). In contrast, patients with perforating infarction showed significant increase in the aortic wall thickness when compared with patients without perforating infarction (p < 0.05). In addition, multivariate logistic analysis revealed that spontaneous echo contrast was an independent predictor of cortical infarction, while intima-media wall thickness of the aorta, hypertension, and age were useful in predicting the risk of perforating infarction. CONCLUSIONS: Transesophageal echocardiography has a potential role in the risk stratification for cortical and perforating infarction in patients with AF. 相似文献
96.
97.
98.
Hirofumi Habu Takeshi Sasaki Takeo Naito Hiroshi Ikawa Yutaka Hirano Kinji Ishikawa Ryo Katori 《The International Journal of Cardiac Imaging》1995,11(1):35-45
Although left ventricular (LV) inflow and pulmonary venous (PV) flow variables estimated by transesophageal Doppler echocardiography (TEE) reflect pulmonary capillary wedge pressure (PCWP), they are also affected by changes in cardiac function. The purpose of the present study was to detect the most appropriate variable for the estimation of PCWP by TEE in patients (pts) with ischemic heart disease. Several variables of LV inflow and left upper PV flow were compared with PCWP in 36 pts (six with angina pectoris and 30 with old myocardial infarction). Early diastolic flow (E) and atrial contraction flow (A) were used as LV inflow, while systolic forward flow (X), diastolic forward flow (Y) and atrial contractile reversal flow (z) were used as PV flow. The peak velocity of each flow wave (Ep, Ap, Xp, Yp, and Zp) and the time-velocity integral (Ei, Ai, Xi, Yi, and Zi) were measured. The ratio of Ep to Ap (Ep/Ap), Ei to Ai (Ei/Ai), Xp to Yp (Xp/Yp), Xi to Yi (Xi/Yi), Zp to Ap (Zp/Ap), Zi to Ai (Zi/Ai) and the systolic fraction of PV forward flow were calculated. Among these variables, the Zi/Ai ratio was most strongly correlated with PCWP (R=0.80). The Zi/Ai ratio may not be influeced by atrial function because the augmentation of atrial pump function increases Zi as well as Ai, and this may be one reason why the ratio correlated well with PCWP.Conclusion: The Zi/Ai ratio is a new useful variable for estimating PCWP by TEE.Abbreviations Ap
peak velocity of left ventricular inflow during atrial contraction
- Ep
peak velocity of left ventricular inflow during early diastole
- Yp
peak velocity of diastolic pulmonary venous forward flow
- Xp
peak velocity of systolic pulmonary venous forward flow
- Zp
peak velocity of pulmonary venous reversal flow during atrial contraction
- Ai
time-velocity integral of left ventricular inflow during atrial contraction
- Ei
timevelocity integral of left ventricular inflow during early diastole
- Yi
time-velocity integral of diastolic pulmonary venous forward flow
- Zi
time-velocity integral of pulmonary venous reversal flow during atrial contraction
- Xi
time-velocity integral of systolic pulmonary venous forward flow 相似文献
99.
Matthew S. Yong Pankaj Saxena Ammar M. Killu Sean Coffey Harold M. Burkhart Siu-Hin Wan Joseph F. Malouf 《Texas Heart Institute journal / from the Texas Heart Institute of St. Luke's Episcopal Hospital, Texas Children's Hospital》2015,42(4):372-376
Transesophageal echocardiography continues to have a central role in the diagnosis of infective endocarditis and its sequelae. Recent technological advances offer the option of 3-dimensional imaging in the evaluation of patients with infective endocarditis. We present an illustrative case and review the literature regarding the potential advantages and limitations of 3-dimensional transesophageal echocardiography in the diagnosis of complicated infective endocarditis.A 51-year-old man, an intravenous drug user who had undergone bioprosthetic aortic valve replacement 5 months earlier, presented with prosthetic valve endocarditis. Preoperative transesophageal echocardiography with 3D rendition revealed a large abscess involving the mitral aortic intervalvular fibrosa, together with a mycotic aneurysm that had ruptured into the left atrium, resulting in a left ventricle-to-left atrium fistula. Three-dimensional transesophageal echocardiography enabled superior preoperative anatomic delineation and surgical planning. We conclude that 3-dimensional transesophageal echocardiography can be a useful adjunct to traditional 2-dimensional transesophageal echocardiography as a tool in the diagnosis of infective endocarditis. 相似文献
100.
《Heart rhythm》2020,17(9):e242-e254
Coronavirus disease 2019 (COVID-19) has presented substantial challenges to patient care and impacted health care delivery, including cardiac electrophysiology practice throughout the globe. Based upon the undetermined course and regional variability of the pandemic, there is uncertainty as to how and when to resume and deliver electrophysiology services for arrhythmia patients. This joint document from representatives of the Heart Rhythm Society, American Heart Association, and American College of Cardiology seeks to provide guidance for clinicians and institutions reestablishing safe electrophysiological care. To achieve this aim, we address regional and local COVID-19 disease status, the role of viral screening and serologic testing, return-to-work considerations for exposed or infected health care workers, risk stratification and management strategies based on COVID-19 disease burden, institutional preparedness for resumption of elective procedures, patient preparation and communication, prioritization of procedures, and development of outpatient and periprocedural care pathways. 相似文献