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81.
PICANO E.; MARRACCINI P.; Lattanzi F.; Levantesi D.; Masini M.; Vacche M.Dalle; DlSTANTE A.; 'ABBATE A. 《European heart journal》1987,8(1):38-44
Twenty-four patients with a history of effort angina, a positiveexercise stress test (EST) and coronary artery disease wereenrolled in the study; 12 patientshada positive dipyridamole-echocardiographytest (DET) and 12 had a negative DET. Each patient performeda total of 4 ESTs in the absence of therapy on two successivedays; for each test the rate-pressure product (RPP), an establishedindex of my ocardial oxygen demand, was measured at the onsetof ischaemia (ST depression >015mV) or at the peakof maximal exercise (if a repeated EST was negative). Taking into account the lowest of the 4 RPP values ( x 1/100)in each patient, there was no significant difference betweenDET-negatives and DET-positives (185.2±49.3 vs 157.4±32.4).Conversely, when considering the highest of the 4 RPP valuesin each patient, there was a significant difference betweenDET-negatives and DET-positives (280.3 ± 63.9 vs 183.3± 37.0; p < 0.01). Thus, DET may provide a clinically useful tool for assessingin the individual the organic ceiling of coronaryreserve, by eliminating the variability in coronary tone, whichmay affect EST reproducibility and the correct evaluation ofthe impairment of organic coronary reserve. 相似文献
82.
目的:探讨和鉴别心电图短P-R间期的产生原因,为临床诊断、治疗提供依据。方法:检测115例受检者的常规导联心电图(RLECG)、头胸导联心电图(HCECG)、食管导联心电图(ELECG),对其中55例临床可疑心律失常和RLECG示短P-R间期者行食管心房调搏电生理检查。结果:①P波出现率和振幅均值比较ELECG>HCECG>RLECG(P<0.01),出现率分别为100%、95%、91%。②HCECGP-R段均值(P<0.01)及变异系数<RLECG。③RLECG波幅低、图形多变是产生心电图短P-R间期的主要原因。结论:作为无创伤性检查方法,HCECG和ELECG可以对短P-R间期者进行初步筛选,而经食管心房调搏能检测ECG短P-R间期的电生理特性,对鉴别诊断有肯定价值。 相似文献
83.
W. N. HABRE E. F. VAN GESSEL CH. MAMIE R. CANTIENI P. M. SUTER 《Acta anaesthesiologica Scandinavica》1994,38(6):612-614
Severe aortic regurgitation was discovered in a young man 21 days after blunt chest trauma and after a prolonged febrile state with positive blood cultures. Using transoesophageal echocardiography (TEE), it was possible to make the differential diagnosis between traumatic rupture and endocarditis as the cause of valvular insufficiency. The use of TEE in the initial evaluation of severe thoracic trauma with an unclear clinical picture is recommended. This method is easy to use at the bedside and gives precise information on the aortic valve and the ascending aorta. 相似文献
84.
The purpose of this study was to evaluate whether the baseline stress-shortening data reflect the contractile state adequately and give results comparable to the evaluation of the end-systolic stress-shortening relationships using pharmacological manipulation of afterload. Five groups were studied (total 152 patients): a control group of 30 healthy volunteers, 32 patients after surgical correction of infantile tetralogy of Fallot, 50 patients treated for childhood malignancies with doxorubicin, 17 patients with left ventricular hypertrophy due to systemic hypertension, and 23 patients with congestive cardiomyopathy. In all patients except those with congestive cardiomyopathy, afterload was altered pharmacologically to evaluate the individual stress-shortening relationship. In all patients the baseline stress-shortening data were evaluated, as well as their relative positions to two predefined normal ranges for the relationship between end-systolic stress and shortening. Additionally, a slope value was calculated from the baseline data of the five groups studied and compared with the data obtained by pharmacological afterload increment. Our data show that the comparison of individual baseline data of end-systolic wall stress and fractional shortening with predefined normal ranges for the relationship between end-systolic stress and shortening is inadequate. The appropriate normal range to compare with is the 95% confidence interval of baseline stress-shortening data in normal subjects. Also the calculation of a slope value from the baseline stress-shortening data of a group of patients seems to be inappropriate. Such a slope value does not necessarily reflect the contractile state, as the specific conditions leading to variations of end-systolic wall stress are undefined and not standardized, and the correlation between baseline stress-shortening data depends largely on the influence of the end-systolic dimension on both parameters. 相似文献
85.
Effects of posture and pneumoperitoneum during anaesthesia on the indices of left ventricular filling 总被引:6,自引:0,他引:6
P. Gannedahl S. Odeberg L.-Å. Brodin A. Sollevi 《Acta anaesthesiologica Scandinavica》1996,40(2):160-166
Background. Laparoscopic surgery requires the use of pneumoperitoneum (PP). When combined with positional changes, pneumoperitoneum may cause marked circulatory alterations.
Methods. Eight anaesthetized cardiovascularly healthy patients, scheduled for laparoscopic cholecystectomy, were studied before and during pneumoperitoneum in three different postures (supine, Trendelenburg and reversed Trendelenburg), employing transesophageal echocardiography and pulmonary artery pressure monitoring.
Results. PP significantly increased end-diastolic area (EDA) and pulmonary capillary wedge pressure (PCWP) irrespective of posture. PCWP was significantly influenced by postural changes, whereas EDA was not. Further, changes in EDA and PCWP covaried during the investigation, but showed no linear correlation. Systolic function, measured as end-systolic area (ESA) and fractional area shortening (FAS), was not altered. Diastolic function, as assessed by the velocity rate of the trans-mitral flow during the early filling phase (E) and the atrial contraction (A), showed no change of the E/A ratio, whereas after the induction of PP there was a significant reduction of the E component.
Conclusions. In cardiovascularly healthy patients, the left ventricular volume is increased during pneumoperitoneum. Further, changes in invasive pressure determinations (PCWP) do not correlate linearly with changes in volume indices of left ventricular filling (EDA). 相似文献
Methods. Eight anaesthetized cardiovascularly healthy patients, scheduled for laparoscopic cholecystectomy, were studied before and during pneumoperitoneum in three different postures (supine, Trendelenburg and reversed Trendelenburg), employing transesophageal echocardiography and pulmonary artery pressure monitoring.
Results. PP significantly increased end-diastolic area (EDA) and pulmonary capillary wedge pressure (PCWP) irrespective of posture. PCWP was significantly influenced by postural changes, whereas EDA was not. Further, changes in EDA and PCWP covaried during the investigation, but showed no linear correlation. Systolic function, measured as end-systolic area (ESA) and fractional area shortening (FAS), was not altered. Diastolic function, as assessed by the velocity rate of the trans-mitral flow during the early filling phase (E) and the atrial contraction (A), showed no change of the E/A ratio, whereas after the induction of PP there was a significant reduction of the E component.
Conclusions. In cardiovascularly healthy patients, the left ventricular volume is increased during pneumoperitoneum. Further, changes in invasive pressure determinations (PCWP) do not correlate linearly with changes in volume indices of left ventricular filling (EDA). 相似文献
86.
Delineation of arch abnormalities is difficult by conventional 2-D echocardiography and MRI has been the investigation of choice. 3-D echocardiography is increasingly used in congenital heart disease for both functional anatomy and morphology. This case report demonstrates that 3-D echocardiography can be used in delineating arch anomalies, which can avoid further imaging that needs a general anaesthetic. 相似文献
87.
Acute thoracic aortic dissection has a high mortality if untreated, so the diagnosis must be rapidly made if mortality is to be lowered significantly. Multiple imaging techniques are often used. This retrospective study from 1988 to 1993 assesses the usefulness in diagnosis of chest X-rays, computed tomography (CT) scanning, aortography, magnetic resonance imaging (MRI), trans-thoracic (TTE) and trans-oesophageal (TOE) echocardiography. Forty-two patients with a final clinical diagnosis of dissection were studied. The diagnosis was confirmed in 16 (13 at surgery and three at autopsy). Three died with dissection given as the only cause for death. Chest X-ray abnormalities were seen in all 19 patients with surgery or death from dissection, with a widened mediastinum and/or dilated aorta being present in 17. In the group of 16 patients with surgery or autopsy proof, CT scans found dissections in 9 of 12 patients studied and correctly classified the type in only five. Aortography was performed in five, with accurate depiction of dissection and type in all. TTE found dissections in three of eight patients imaged by this method. MRI and TOE were performed each on two patients, with accurate depiction of dissection and type in each. Because of the relatively low sensitivity of CT scanning in defining aortic dissections Westmead Hospital is currently assessing the use of TOE as the prime imaging modality prior to surgical intervention. 相似文献
88.
KEVIN RYAN M.D. RAJAT S. SANYAL M.D. LUIZ PINHEIRO M.D. NAVIN C. NANDA M.D. 《Echocardiography (Mount Kisco, N.Y.)》1992,9(3):277-285
Our experience in using biplane transesophageal echocardiography in the assessment of coarctation of the aorta is described. 相似文献
89.
Lincoln C. L. Lee Ian W. Black rew Hopkins Warren F. Walsh 《Internal medicine journal》1992,22(5):527-531
Cardiac ultrasound and upper gastrointestinal endoscopy are relatively old technologies. With the introduction of new ultrasound probes and by incorporating ultrasound technology into conventional endoscopes, ‘new tricks’ in cardiac imaging were discovered. Posterior structures of the heart are now able to be imaged clearly by the ultrasound probe from the oesophagus. Consequently, better resolution of cardiac anatomy allows more accurate diagnosis of cardiac pathologies which is not possible using conventional transthoracic (TT) approach. Over a period of two years, 1200 cases of transoesophageal echocardiography (TOE) were undertaken in our institution. The major indications were diseases of the aorta (10%), source of cardioembolism (28%), assessment of native and prosthetic valve function (20%), suspected endocarditis and its complication (17%), pre and post percutaneous transluminal mitral valvotomy (PTMV [13%], congenital heart disease (2%) and others (10%). The greatest impact with TOE is in the diagnosis of aortic dissection and transection, TOE is superior to conventional TT approach in detecting potential source of embolism, valvular vegetations and its complication, native and prosthetic valve dysfunction and LA thrombus prior to PTMV. Observations by TOE such as spontaneous echo contrast (SEC) in the left atrium open new challenges for further research in its role in the pathogenesis of LA thrombus and its association with cardioembolic event. Other areas of interest include; reclassification of distal aortic dissection and the use of TOE in intra-operative work. 相似文献
90.
C Joseph Muniz Arthur C Fleischer Edwin F Donnelly Murray J Mazer 《Journal of ultrasound in medicine》2002,21(2):129-133
OBJECTIVE: To assess the accuracy of three-dimensional color Doppler sonography and uterine artery arteriography in depicting changes in fibroid vascularity before and after embolization. METHODS: Preembolization and postembolization three-dimensional color Doppler sonography and selective uterine artery arteriography were retrospectively compared in 15 patients who underwent uterine artery embolization for treatment of symptomatic fibroids. Three-dimensional color Doppler sonography was performed by using a scanner with color power angiographic imaging capability. Vascularity was quantified by using an estimation of power-weighted pixel density as described by our group in previously published studies. Uterine artery arteriography was performed by using a standard selective microcatheter embolization technique. For purposes of comparison, fibroids were classified as either hypervascular or hypovascular relative to myometrial vascularity before and minutes to several hours after uterine artery embolization. Changes in fibroid vascularity (i.e., from hypervascular to hypovascular) as depicted by three-dimensional color Doppler sonography were compared with those shown on uterine artery arteriography and classified as being in agreement or disagreement. RESULTS: In 13 (87%) of 15 patients there was agreement; in 2 (13%) of 15 there was disagreement. In both cases of disagreement, three-dimensional color Doppler sonography showed collateral flow not depicted by uterine artery arteriography The mean reduction in quantitated vascularity after uterine artery embolization was 44% (range, 19%-78%). CONCLUSIONS: Three-dimensional color Doppler sonography accurately depicts fibroid vascularity and in some cases can reveal collateral flow not depicted by uterine artery arteriography. 相似文献