Raimund Erbel

Percutaneous transluminal coronary angioplasty in patients with stable and unstable angina pectoris: Analysis of early and late results

Percutaneous transluminal coronary angioplasty (PTCA) was performed in 50 patients with stable and in 50 patients with unstable angina pectoris, each patient showing an isolated stenosis of more than 80% of the cross-sectional area of a single coronary artery. The technical success rate was 66% in the stable groups (26 of 37 patients [70%] with left anterior descending artery [LAD], 7 of 12 patients [58%] with right coronary artery [RCA]) and 74% in the unstable group (27 of 34 patients [79%] with LAD, 10 of 15 patients [67%] with (RCA). The increase in stenotic area in the unstable group exceeding that in the stable group for LAD stenoses (41.5 +/- 15.1% vs 32.3 +/- 14.5%, p less than 0.03), while in RCA stenoses the results in the stable group were better (45.1 +/- 17.6% vs 32.7 +/- 12.3%, n.s.). One acute vessel occlusion necessitating an emergency bypass operation occurred in each group (2%). The patient in the stable group died (total mortality rate 1%). Sixty-three of the successfully treated patients were routinely restudied 6 months later. According to clinical symptoms, 23% of the stable and 36% of the unstable group were in functional classes III and IV. From the anatomical viewpoint, a restenosis (greater than 85%) was found in 17% of the stable and in 24% of the unstable group. A further spontaneous decrease (greater than 10%) of the vessel obstruction was found in 47% of the stable group and in 12% of the unstable group.(ABSTRACT TRUNCATED AT 250 WORDS)

Advances in Noninvasive Cardiology

Digital imaging is being increasingly applied in diagnostic medicine. New digital image modalities are extending the range of diagnostic techniques, and it is anticipated that novel imaging technologies will gradually replace the traditional photographic X-ray process. They all produce digital data sets which are far beyond those data volumes handled by conventional computer systems. New technologies are, therefore, required to build distributed picture information systems which support the user during acquisition and evaluation of all the types of pictures. Key components of such systems are storage modalities. Storage systems to store millions of pictures which are needed for background storage, i.e. picture archives, will be feasible by the application of the Digital Optical Recording (DOR) technology. Digital optical disks of 30 cm in diameter will store 1.6 . 1010 bit of data which is equivalent to some 10.000 digital pictures such as CT or some 1000 digitized large format X-rays. Digital Picture Archiving and Communication Systems based on this technology will probably have an essential impact on the way of operating with pictorial information in diagnostic medicine.

Left ventricular contrast echocardiography — echoventriculography

Echographic contrast agents were first used for structure identification [1, 2]. Pooled data analysis revealed a high safety [3]. Special agents have been developed in order to standardize right heart opacification [4] and to enhance echocardiographic Doppler signals [5–9]. The latter effect was not expected [9]. All agents contain air as reported by others between 12 and 35 µl/ml [9]. The stability reaches more than 5 min. Injections of up to 20 ml are necessary. The osmolality is between 345 and 1740 mosm/kg H2O [9].

Acute changes of myocardial function by PTCA. Evaluation by two-dimensional echocardiography

Two-dimensional echocardiography allows a detailed analysis of global and regional left ventricular function [1]. The aim of our study was to analyse continuously the left ventricular function during percutaneous transluminal coronary angioplasty (PTCA) by two-dimensional echocardiography.

Left ventricular contrast echocardiography — echoventriculography — stress echocardiography

Echographic contrast agents were first used for structure identification [1, 2], and pooled data analysis revealed a high level of safety [3]. Special agents have been developed in order to standardize right heart opacification [4] and to enhance echocardiographic Doppler signals [5-9]. The latter effect was not expected [9]. All agents contain between 12 and 35 μl/ml air, as reported by others [9]. The stability lasts for more than 5 min. Injections of up to 20 ml are necessary. The osmolality is between 345 and 1740mOsm/kg H2O [9].

Evaluation of the Effect of Thrombolytic Therapy on Left and Right Ventricular Function by Two-Dimensional Echocardiography and Cineventriculography

Infarct size is the main predictor of prognosis in patients with acute myocardial infarction [1–3]. Depending on infarct size, regional and global left ventricular functions are depressed, leading to cardiogenic shock, when more than 40% of the myocardium is involved [4].

Improved tolerance of intracoronary balloon inflation with a modified Grüntzig balloon angioplasty catheter

A modified Gruntzig coronary angioplasty catheter, designed to permit continuous antegrade perfusion during dilatation was evaluated. During in-vitro tests with blood, flow rates between 12 and 28ml/min were measured at effective pressures between 50 and 100 mmHg. During in vivo tests in five dogs this catheter was compared with conventional catheter types which prevent antegrade flow during balloon inflation.

Quantification of Left Ventricular Function by Two-Dimensional Echocardiography

Two-dimensional echocardiography has overcome some of the major methodological limitations of M-mode echocardiography [1]. In addition the introduction of apical echocardiography by Silverman and Schiller [2] has opened up the possibility of imaging the left ventricle in long-axis in multiple projections. Usually the apical four- and two-chamber views are scanned. In these two cross sections of the left ventricle, aortic and mitral valves represent landmarks. Images of the left ventricle in the two-chamber view are very similar to cineventriculograms in the 30° right anterior oblique (RAO) projection. Therefore this scan plane was called “RAO-equivalent view”.