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41.
42.
Distinguishing between acute and subacute massive pulmonary embolism by conventional and Doppler echocardiography. 总被引:1,自引:1,他引:1 下载免费PDF全文
W Kasper A Geibel N Tiede D Bassenge E Kauder S Konstantinides T Meinertz H Just 《Heart (British Cardiac Society)》1993,70(4):352-356
OBJECTIVE--To determine the ability of conventional and Doppler echocardiography to distinguish between minor, acute massive, and subacute massive pulmonary embolism in patients with confirmed pulmonary embolism. DESIGN--Prospective study of a consecutive series of 47 patients with confirmed pulmonary embolism. SETTING--Department of internal medicine, university clinic. PATIENTS--11 patients (23%) had minor, 23 patients (49%) had acute massive, and 13 patients (28%) had subacute massive pulmonary embolism. RESULTS--Dilatation of the right ventricular cavity (33 (92%)) and asynergy of the right ventricular free wall (29 (81%)) were seen only in patients with acute and subacute massive pulmonary embolism (n = 36). 23 (64%) with pulmonary hypertension had tricuspid regurgitation. The velocity of the tricuspid regurgitant jet correlated with the pulmonary arterial pressure (r = 0.88, SEE = 11.6 mm Hg) and was significantly lower in patients with acute massive pulmonary embolism (3.0 (0.4) m/s, n = 12) than in patients with subacute massive pulmonary embolism (4.2 (0.6) m/s; n = 11) (p < 0.001). The use of predefined indices (right ventricular free wall thickness > 5 mm; tricuspid regurgitant jet velocity > 3.7 m/s; and the occurrence of both a dilated right ventricular cavity with normal interventricular septal motion, or an inspiratory collapse of the inferior vena cava, or both) correctly identified 11 of 13 patients (85%) with subacute massive pulmonary embolism. CONCLUSION--Conventional and Doppler echocardiography were successful in evaluating the haemodynamic consequences of pulmonary embolism. 相似文献
43.
Karola Kálló Sarolt Lehóczki Zsuzsanna Just Zita Gyurkovits György Pálfi Hajnalka Orvos 《The journal of maternal-fetal & neonatal medicine》2015,28(5):540-543
Objective: Records of metric data of birth, serve not only the medical needs of the newborn baby, but are also indicators to assess the status of public health.Methods: This is a retrospective study of 4946 newborns (singleton: 2508 boys and 2365 girls) born in 1989 and in 2009 at the Department of Obstetrics and Gynaecology of the University of Szeged. We aimed as to compare and map the metrical changes over 20 years, and to describe the averages of four body parameters of the normal birth weight (2500–4000?g) subgroup (3993 singleton babies) in both years. Statistical analysis was performed with SPSS 17.0.Results: In 1989, the mean birth weight was 3223.770?±?559.595?g, birth length 49.551?±?2.729?cm, chest circumference 32.181?±?2.231?cm, and head circumference 34.122?±?1.688?cm. In 2009, the birth weight was 3309.673?±?582.630?g, birth length 49.515?±?2.658?cm, chest circumference 32.736?±?2.392?cm and head circumference 33.854?±?1.768?cm. The mean birth weight, chest circumference and the maximum value of birth weight have thus increased. The mean maternal age shifted to 30.21?±?4.863 years, which is an increase of 3.57 years in 20 years.Conclusion: The body parameters of newborns changed significantly between 1989 and 2009. As underlying causes changes in eating habits and lifestyle of the mother are to be mentioned. 相似文献
44.
A 33 year old woman with Marfan's syndrome and aortic root dissection was studied with precordial and suprasternal echocardiography. The precordial approach revealed some typical features of aortic root dissection. With suprasternal echocardiography it was possible to visualize the characteristic diagnostic feature of this disease: within the aortic lumen an m-shaped pattern--the aortic intimal flap--moving downward to the posterior aortic wall during systole. The diagnosis was confirmed with aortic cineangiography and intraoperative findings. Thus, suprasternal echocardiography can be a useful method of detecting aortic root dissection, especially in patients with aortic arch dissection alone. 相似文献
45.
A simple and accurate noninvasive method to quantify the degree of mitral regurgitation (MR) is lacking. Therefore, the ratio of the aortic (AVO) to mitral valve opening area (MVO) from 2-dimensionally guided M-mode echocardiographic tracings was examined as an estimate for the presence and severity of MR. Seventy-two patients who had undergone catheterization were studied: 49 with idiopathic dilated cardiomyopathy, 7 with coronary artery disease and 16 with organic MR. Twenty-eight patients had no MR (group I), 23 had mild/moderate MR (group II) and 21 had severe MR (group III). The AVO/MVO ratio was 0.86 +/- 0.2 in group I, 0.53 +/- 0.1 in group II and 0.31 +/- 0.1 in group III (p less than 0.001). An AVO/MVO ratio of 0.65 or less predicted MR with a sensitivity of 98% and a specificity of 86%. Furthermore, a strong relation was found between the ratio and the angiographic severity of MR. Thus, the AVO/MVO ratio is a simple echocardiographic parameter for detecting the presence and severity of MR. 相似文献
46.
Marked decrease in sleepiness in patients with sleep apnea by etanercept, a tumor necrosis factor-alpha antagonist 总被引:9,自引:0,他引:9
Vgontzas AN Zoumakis E Lin HM Bixler EO Trakada G Chrousos GP 《The Journal of clinical endocrinology and metabolism》2004,89(9):4409-4413
The proinflammatory cytokines, TNFalpha and IL-6, are elevated in obstructive sleep apnea (OSA) and have been proposed as mediators of excessive daytime sleepiness in humans. We tested the effects of etanercept, a medication that neutralizes TNFalpha and is approved by the FDA for the treatment of rheumatoid arthritis, in eight obese male apneics. These patients participated in a pilot, placebo-controlled, double-blind study during which nighttime polysomnography, multiple sleep latency test, and fasting blood glucose and plasma levels of IL-6, C-reactive protein, insulin, and adiponectin were obtained. There was a significant and marked decrease in sleepiness by etanercept, which increased sleep latency during the multiple sleep latency test by 3.1 +/- 1.0 min (P < 0.05) compared with placebo. Also, the number of apneas/hypopneas per hour was reduced significantly by the drug compared with placebo (52.8 +/- 9.1 vs. 44.3 +/- 10.3; adjusted difference, -8.4 +/- 2.3; P < 0.05). Furthermore, IL-6 levels were significantly decreased after etanercept administration compared with placebo (3.8 +/- 0.9 vs. 1.9 +/- 0.4 pg/ml; adjusted difference, -1.9 +/- 0.5; P < 0.01). However, no differences were observed in etanercept vs. placebo in the levels of fasting blood glucose and plasma C-reactive protein, insulin, and adiponectin. We conclude that neutralizing TNFalpha activity is associated with a significant reduction of objective sleepiness in obese patients with OSA. This effect, which is about 3-fold higher than the reported effects of continuous positive airway pressure on objective sleepiness in patients with OSA (0.9 vs. 3.1 min), suggests that proinflammatory cytokines contribute to the pathogenesis of OSA/sleepiness. 相似文献
47.
Alterations of skeletal muscle in chronic heart failure. 总被引:28,自引:0,他引:28
BACKGROUND. The present study was designed to define the prevalence and characteristics of skeletal muscle alterations in patients with chronic heart failure (CHF) and their relation to exercise capacity. METHODS AND RESULTS. The ultrastructure of skeletal muscle was analyzed by ultrastructural morphometry in 57 patients with CHF and 18 healthy controls. The volume density of mitochondria (Vvm) and the surface density (Svmc) of mitochondrial cristae were evaluated as a structural correlate of oxidative capacity of skeletal muscle. Vvm and Svmc were reduced by approximately 20% in patients with severe CHF irrespective of age and etiology. The cytochrome oxidase activity in mitochondria as determined by cytochemistry and subsequent morphometry in a subset of patients (n = 10) was significantly decreased in heart failure (p less than 0.01). The capillary length density of skeletal muscle was reduced in CHF (n = 12, p less than 0.05), and the fiber type distribution was shifted to type II fibers (n = 15, p less than 0.05). Vvm and Svmc were significantly related to peak exercise VO2 (r = 0.56, p less than 0.001, n = 60) and to VO2 at anaerobic threshold (r = 0.535, p less than 0.0001, n = 60). In 16 patients with severe heart failure, Vvm was inversely related to the duration of heart failure (r = 0.545, p less than 0.03). In 11 patients who underwent repeat biopsies after 4 months, a correlation was observed between the change in Vvm and the change in peak exercise VO2 (r = 0.89, p less than 0.001). CONCLUSIONS. These findings indicate that patients with CHF develop significant ultrastructural abnormalities of skeletal muscle reflecting a depressed oxidative capacity of working muscle. It appears that these alterations of skeletal muscle contribute to the decreased exercise capacity of these patients but are, in principle, reversible by an effective treatment regimen. 相似文献
48.
M. Brunner T. S. Faber A. Jeron M. Zehender H. Just 《Intensivmedizin und Notfallmedizin》1998,35(1):66-76
Zusammenfassung Die ad?quate Versorgung von Patienten, die bereits einmal einen Herz-Kreislaufstillstand durch tachykarde Arrhythmien überlebt
haben, war lange Zeit auf eine Behandlung mit Antiarrhythmika beschr?nkt, wenn der Rhythmusst?rung keine behebbare orga-nische
Ursache zugrunde lag. Trotz optimierter Pharmakotherapie sterben 30% dieser Patienten innerhalb von drei Jahren durch eine
erneute maligne Arrhythmie. Deshalb wurde in den letzten Jahren die Implanta-tion von automatischen, implantierbaren Kardioverter-Defibrillatoren
(ICD) der Standard bei der Versorgung dieser Patienten. Zunehmend werden ICDs auch bei Patienten mit stark erh?htem Risiko
für einen pl?tzlichen Herztod ohne überlebten Kreislaufstillstand implantiert, ins-besondere bei Patienten mit Kardio-myopathie
oder angeborenen ar-rhythmogenen Anomalien des Herzens. In neuen klinischen Studien konnte bei selektierten Patienten ein
deutlicher überlebensvorteil gegen-über der Behandlung mit Anti-arrhythmika gezeigt werden [7].
Die Implantation von ICDs wird bei den neuen transven?sen Systemen ohne Thorakotomie durchgeführt, wodurch das Operationsrisiko
wesentlich verringert wurde. Moderne ICDs werden unter den linken M. pectoralis major implantiert, eine mehrpolige Elektrode
im rechten Ventrikel dient der Wahrnehmung, der Stimulation und der Schockab-gabe.
Die Ger?te sind in weiten Bereichen patientenspezifisch programmierbar und erlauben so eine differenzierte Erkennung und
mehrstufige Therapie von ventrikul?ren Tachykardien und Kammerflimmern. Neben der Defibrillation und der synchronisierten
Kardioversion stellt die antitachykarde Stimulation eine hocheffektive und für die Patienten angenehme Methode zur Beendigung
von langsamen ventrikul?ren Tachykardien dar. Der interne Speicher moderner ICDs dokumentiert nicht nur die Anzahl der Arrhythmien
und die abgegebene Therapie, auch intrakardiale EKGs vor und nach den Episoden k?nnen ausgelesen werden. Diese Eigenschaften
erlauben heute eine sehr spezifische und individuelle Anpassung der Therapie an die zugrundeliegende Arrhythmie.
Eingegangen: 3. September 1997 Akzeptiert: 4. Oktober 1997 相似文献
49.
Häfner HM Thomma SR Eichner M Steins A Jünger M 《Clinical hemorheology and microcirculation》2003,28(3):121-128
Emla cream is frequently used in surgical dermatology and in anesthesiology, for instance, during vascular surgery procedures. Because local anesthetics can have a vasoactive effect in addition to producing analgesia, we decided to document the effect of 5% Emla cream on cutaneous circulation in a prospective, placebo-controlled study. Skin circulation was monitored continuously under standardized conditions using video capillaroscopy, laser Doppler flowmetry and skin temperature. Recordings were made at the nailfold of the fourth finger (DIV) of the left hand of 12 volunteers with healthy veins over an observation period of 60 minutes under either Emla occlusive dressing or an occlusive dressing with placebo. Mean capillary red blood cell velocity changed only minimally under the Emla occlusive dressing, while placebo occlusive dressing led to a reduction of mean capillary red blood cell velocity from 0.21 mm/s to 0.12 mm/s (p<0.01). There was no statistically significant change of arterial capillary diameter under Emla or placebo occlusive dressing. Skin temperature dropped after 60 minutes of Emla cream occlusive dressing from an initial 26.7 to 24.0 degrees C (-10.1%; p<0.02). The same duration of placebo caused skin temperature to drop from 27.6 to 23.0 degrees C (-16.7%; p<0.001). Laser Doppler flux (543 nm) rose 13% with Emla (p=0.9) and dropped 41.9% under placebo occlusive dressing (p<0.03). Emla cream upregulated nutritive perfusion. No clinically relevant vasoconstrictive effects are expected from an application period of 60 minutes. 相似文献
50.