Biomedical subjects

M Gwechenberger

Publications and source records attributed to M Gwechenberger.

22 records · Page 2Linked to original sources

PubMed1996

Assessing coronary stenosis. Quantitative coronary angiography versus visual estimation from cine-film or pharmacological stress perfusion images.

UNLABELLED: Visual judgment of stenosis severity from cine-film or single-photon emission computed tomographic dipyridamole perfusion images was compared to assessment of stenosis severity as measured with digital quantitative coronary angiography. Thirty patients with angiographically verified single-vessel disease underwent dipyridamole thallium stress testing within 90 days of angiography. RESULTS: A percent diameter stenosis of > or = 50%, a percent area stenosis of > or = 75%, and a stenotic flow reserve of < 3.75 measured by quantitative coronary angiography (CMS, version 1.1, Medis Inc.) corresponded to haemodynamically significant stenosis as evaluated by visual estimates from cine-film or perfusion images. Quantitative coronary angiography percent diameter stenosis (51.2% +/- 12.6%) correlated closely (r = 0.74) but underestimated significantly visual assessment of stenosis severity from cine-film (69.3% +/- 21.2%; P = 0.0001). However, quantitative coronary angiography percent area stenosis (74.7% +/- 11.7%) more closely reflected visual estimates from cine-film (P = 0.19). Quantitative coronary angiography stenotic flow reserve showed the highest positive and negative predictive value regarding visual estimates from cine-film (88%, 86%) or perfusion images (88%, 64%) followed by percent diameter stenosis (86%, 75% 86%, 56%) and percent area stenosis (87%, 80%, 87%, 60%), respectively. CONCLUSION: Evaluation of coronary lesions by quantitative coronary angiography corresponds closely with visual estimates from cine-film and haemodynamic significance as evaluated by dipyridamole perfusion images.

Adult↗

PubMed1995

Does dyspnoea during dipyridamole cardiac stress testing indicate bronchospasm and is the pretest clinical history predictive of this side-effect?

This study investigates the acute effects of intravenous dipyridamole (0.7mg/kg) on pulmonary airflow in relation to clinical parameters suggestive of chronic obstructive pulmonary disease (COPD) in order to assess predictive and causative factors of dyspnoea during cardiac stress testing. Mild pulmonary airflow obstruction was noted in all patients, but reached statistical significance only in small airways (FEF75-85%: -7%; P=0.034). The changes in pulmonary function parameters were independent of the clinical history. Dyspnoea under dipyridamole stress testing occurred in parallel with angina, yet was not associated with ischaemic or non-ischaemic left ventricular dysfunction. These data do not support the use of dipyridamole stress testing in asthmatics, but show that (1) the acute effects of a diagnostic dose of dipyridamole on pulmonary airflow are mild even in patients with a history suggestive of COPD and (2) dyspnoea during dipyridamole testing is not necessarily indicative of bronchospasm.

Adult↗

PubMed1995

[Change in the patient profile in coronary heart disease at the time of initial evaluation with coronary angiography between 1975 and 1989].

BACKGROUND AND METHOD: After the introduction of coronary angioplasty in the late 1970s, diagnostic coronary angiography has been performed for reasons other than to evaluate patients for bypass surgery. The aim of this study was to evaluate the change of the patient-profile at the time of the first angiographic evaluation of coronary artery disease. Therefore, 6456 patients in the period from 1975 to 1989 were included. RESULTS: The observation period of 15 years was divided into three parts of 5 years each (group 1 1975-79, N = 1130); group 2 1980-84, N = 2412; and group 3 1984-89, N = 2914). The mean age (53.3 +/- 7.4 vs. 54.4 +/- 8.4 vs. 57.8 +/- 9.3; p < 0,0001) as well as the number of patients of age > 64 years (6.4% vs. 9.6% vs. 25.9%, p < 0.0001) increased significantly over the 15 years. Women were found twice as often in group 3 vs. group 1 (10% vs. 16% vs. 19%; p < 0.0001). In the observation period the left ventricular ejection fraction (51.1 +/- 15.9 vs. 53.8 +/- 14.4 vs. 55.4 +/- 16.2) and one-vessel disease (37.2% vs. 38.2% vs. 42.4%) increased significantly (p < 0.0001), whereas multi-vessel disease decreased (57.7% vs. 56.6% vs. 52.6%). CONCLUSION: Between 1975 and 1989 significantly more women, more patients over 64 years of age, and more patients with lower degree of coronary disease were first evaluated with coronary angiography. The change of patient-profile may have been influenced by increased risk-factors among women and the possibility to offer patients an alternative therapy to bypass surgery.

Adult↗

PubMed1994

Severe complications following thrombolytic therapy of an acute thrombosis of a prosthetic mitral valve.

Thrombosis of prosthetic cardiac valves is a rare but potentially lethal complication. As emergency surgical intervention of thrombotic prosthetic cardiac valves is correlated with high mortality, fibrinolytic therapy has been recently recommended as a therapy with high efficacy and no severe side effects. We report on a patient with thrombosis of a prosthetic mitral valve who developed severe embolic complications following the administration of the thrombolytic agent. On admission the patient showed signs of incipient cardiogenic shock. The diagnosis of thrombotic obstruction of the prosthetic mitral valve was confirmed by transesophageal echocardiography. The effective valve area was 0.41 cm2. Pulmonary arterial blood pressure and wedge pressure were significantly elevated. A fibrinolytic therapy with recombinant tissue-type plasminogen activator according to the Neuhaus scheme was attempted. Within 60 min after start of treatment the effective valve area increased (1.41 cm2), and the pulmonary capillary wedge pressure decreased. However, peripheral and cerebral embolism occurred. Occlusion of the right brachial and right femoral artery was ascertained by Doppler ultrasound. Embolism into the right leg made an embolectomy with a Fogarty catheter necessary. Computed tomography revealed two lesions located in the occipital and left temporal area of the brain. Correlated with the lesions evaluated in computed tomography, right hemiplegia and complete aphasia was observed. The neurological status of the patient has only slightly improved to the present. To our knowledge no severe persistent neurological deficits following thrombolytic therapy have been reported. We therefore assume that the risk of severe neurological complications is underestimated.(ABSTRACT TRUNCATED AT 250 WORDS)

Acute Disease↗