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A von Hehn

Publications and source records attributed to A von Hehn.

7 recordsLinked to original sources
PubMed1995

[3-D echocardiography reconstruction of the thoracic aorta].

Since the beginning of the nineties the combination of echocardiography equipment with a computer algorithm for 3-D reconstruction is commercially available. The initial experiences with this unit (TomTec-system, Munich, Germany) in clinical and intraoperative settings are reported. The described unit consisted of a specially constructed transesophageal echo probe, in which the transducer (5 MHz) is mounted on a sliding carriage allowing free up and down movement in axial directions. The transducer obtains digitally dynamic 3-D information by automated pull-back of the transducer in 0.67 mm slices, gated to ECG and respiration. The information is stored on a hard disk and in the computer RAM. The acquisition time--depending on different trigger intervals--ranges from 5 to 10 minutes, usually not longer than for conventional TEE. The images are stored in special 4-D (that is 3-D in motion) data sets, allowing the calculation of any desired plane in real-time at a triggered ECG phase or dynamically. Thus this technique gives the capability of retrospective reconstruction of any view into the aorta in contrast to the omniplane TEE examination, the so-called anyplane echocardiography. In the clinical management of patients with thoracic aortic diseases transesophageal echocardiography (TEE) has become the central diagnostic tool as well as for the follow-up. This is caused by its high sensitivity and specificity comparable with that obtained by MRI. Nevertheless in a small percentage of cases there remains a questionable situation concerning the morphology of the distal ascending aorta and the aortic arch illuminated by the use of 3-D reconstruction.

Aged↗
PubMed1994

[Initial experiences with echocardiography 3D reconstruction of the thoracic aorta].

Although the transesophageal echocardiography (TEE) has become the method of choice for the diagnosis as well as for the follow-up of patients with thoracic aortic aneurysms and aortic dissections, there are still some uncertainties concerning the morphology, especially that of the aorta ascendens and the aortic arch. The introduction of the 3D reconstruction now allows an exact volumetry, especially in the follow-up of aortic aneurysms, and may be helpful in better timing of the surgical intervention which is not only influenced by the horizontal diameter. Thus the 3D reconstruction of the thoracic aorta opens up a wide new field of TEE allowing a more detailed guidance preoperatively as well as a better definition of postoperative morphology.

Adult↗
PubMed1993

Diagnosis of heart tumours by transoesophageal echocardiography: a multicentre study in 154 patients. European Cooperative Study Group.

In a retrospective multicentre study, the diagnostic potential of transoesophageal 2D-echocardiography (TEE) as compared to precordial 2D-echocardiography (TTE) was determined in 154 patients with primary or secondary tumours of the heart. Additionally, the value of standard diagnostic parameters, such as symptoms, X-ray of the chest and electrocardiogram were evaluated. In 84 patients (24 male, 60 female; age 20-85, mean 56.6 years) intracardial tumours were present, and 70 patients (37 male, 33 female; age 18-79, mean 44.3 years) presented with peri- or paracardial tumours. The main symptoms of patients with intracardial tumours were dyspnoea (60.7%), vena cava syndrome (22.2%) and chest pain (20.2%). Embolization was found in 11.9%. Left or right atrial enlargement was observed on chest X-ray in 23 patients, and echocardiographic abnormalities in 17 cases. The patients with peri- or paracardial tumours presented with dyspnoea in 51.4% of cases, loss in body weight in 20.0% and with vena cava syndrome and chest pain in 17.1%. The chest X-ray was abnormal in 56 patients. Unspecific ST segment changes in the electrocardiogram were observed in five, and arrhythmias in seven cases. Diagnosis of atrial myxomas was achieved by TTE in 95.2%, by TEE in 100%, by angiography in 78.4%, by computed tomography (CT) or magnetic resonance tomography (NMR) in 70%. Identification of the attachment point was made by angiography in 8.1%, by TTE in 64.5% and by TEE in 95.2%. In 22 patients with intracardial tumours (myxomas excepted) diagnosis was achieved by TTE in 90.9%, by TEE in 100%, by CT or NMR in 88.9% and by angiography in 50%.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1991

[Marfan syndrome and pregnancy, complicated by dissecting aneurysm].

Pregnant women with a Marfan syndrome carry a risk of developing an aortic arc dissection. As the developing aneurism may be diagnosed by echocardiography, this method should be applied repeatedly during pregnancy. We report the case of a Marfan patient, who developed an acute aortic dissection during the third trimester of her pregnancy and discuss the guidance and surveillance of Marfan patients who are or wish to become pregnant.

Aortic Dissection↗
PubMed1987

Ventricular arrhythmias in hypertensive heart disease with and without heart failure.

Forty-two patients with hypertensive heart disease but without coronary macroangiopathy were examined for ventricular arrhythmias by means of 24-h, long-term electrocardiograms (ECG). They were divided into two groups according to specific criteria. Group 1 was composed of 30 patients with left ventricular hypertrophy but normal ventricular volumes, as determined by ventriculography. Group 2 comprised 12 patients with left ventricular hypertrophy and dilated left ventricles. By means of two 24-h, long-term ECGs, the mean absolute number of ventricular extrasystoles was ascertained and severity was determined according to the classification of Ryan et al. On average, patients in group 2 showed 7.830 +/- 6.579 extrasystoles, a significantly higher (p less than 0.001) number than in patients in group 1 who had 1.132 +/- 2.639 extrasystoles/24 h. Moreover, 67% of patients in group 2 had Ryan's class 4a ventricular arrhythmias (couplets) or 4b disorders (ventricular tachycardia). However, corresponding rhythm disorders could be found in only 7% of the patients in group 1. A comparison of hemodynamic parameters and ventricular arrhythmias showed that a decreasing left ventricular ejection fraction (EF, expressed in %), a decreasing mass/volume ratio (LVMM/EDV), and an increasing systolic wall stress of the left ventricle (Tsyst) are accompanied by a nearly linear increase in ventricular extrasystoles and in the severity of the ventricular arrhythmias. During long-term ECGs, nine of 10 patients with systolic wall stress of greater than or equal to 300 dyn x 10(3)/m2 showed Ryan's class 4a or 4b ventricular arrhythmias or ventricular tachycardia during programmed ventricular stimulation. However, 12 patients with normal systolic wall stress (less than or equal to 200 dyn x 10(3)/m2) showed no or only Ryan's class 1 ventricular arrhythmias. Our investigations have shown that cardiac ventricular rhythm disorders frequently occur during decompensated hypertensive heart disease, but to a lesser extent in left ventricular hypertrophy without dilation. Further investigations are needed to demonstrate whether regression of left ventricular hypertrophy is accompanied by a reduction in the incidence of ventricular arrhythmias.

Adult↗