Computers and the Internet in cardiac care: Will cardiology rise to this extraordinary opportunity?

Aktuelle Komplikationsrate der perkutanen transluminalen Koronarangioplastie bei stabiler und unstabiler Angina

During a four-year period (1983-1986) percutaneous transluminal coronary angioplasty (PTCA) was performed on 930 patients with stable or unstable angina with a mortality rate of 0.4%. A transmural myocardial infarct developed in 1.1% and 1.0% of patients required an urgent aorto-coronary bypass. Thus the total rate of severe cardiac complications was 2.5%. Compared with the years 1983-1985, there was in 1986 a significant fall in the number of deaths and of myocardial infarcts from 2.2% to 0.5% (P less than 0.05), while there was a nonsignificant increase in emergency coronary bypass surgery from 0.7 to 1.3%. Patients with unstable angina compared with those with stable angina had a signifi…

American College of Cardiology/ European Society of Cardiology international study of angiographic data compression phase III. Measurement of image quality differences at varying levels of data compression

Objectives We sought to investigate up to which level of Joint Photographic Experts Group (JPEG) data compression the perceived image quality and the detection of diagnostic features remain equivalent to the quality and detectability found in uncompressed coronary angiograms. Background Digital coronary angiograms represent an enormous amount of data and therefore require costly computerized communication and archiving systems. Earlier studies on the viability of medical image compression were not fully conclusive. Methods Twenty-one raters evaluated sets of 91 cine runs. Uncompressed and compressed versions of the images were presented side by side on one monitor, and image quality differe…

Linksventrikuläre Funktionsanalyse: Kritische Wertung der Stellung der Echokardiographie

Mit Hilfe der M-mode-Echokardiographie last sich das Myokard des linken Ventrikels mit Endo- und Epikard abgrenzen. Die zeitliche Auflosung der M-mode-Echokardiographie ubertrifft dabei alle anderen zur Verfugung stehenden Methoden. Aus den diastolischen und systolischen Werten wird die Verkurzungsfraktion und die Wanddickenanderung bestimmt. Liegt keine Wandbewegungsstorung vor, kann die globale Ventrikelfunktion uber die Durchmesserbestimmung (Abb. 1) sicher abgeschatzt werden [13]. Der enddiastolische Durchmesser wurde dabei zu Beginn von QRS, der endsystolische Durchmesser zum Zeitpunkt der Inzisur der Septumbewegung bestimmt [13]. Nur fur wenige Patienten konnte eine fehlerhafte Klassi…

Coronary Angioplasty in Unstable Angina

When Gruntzig introduced the revolutionary method of percutaneous transluminal coronary angioplasty (PTCA) for the treatment of coronary artery stenoses, he initially devoted this technique only to patients with stable angina pectoris [8]. Very soon, however, it was discovered simultaneously by Williams et al. [19] and by our group [12] that this method can also be used in patients with unstable angina pectoris. The earliest experiences with PTCA in 1980 were published by our two groups (Table 1). In these series the average degree of stenosis was somewhat lower than that today, while the residual stenosis after treatment was slightly higher. The very rough balloons and guiding catheters av…

Image Processors for Digital Angiography Algorithms and Architectures

After a period of experimental and clinical development,(1–9) digital processing of angiographic X-ray video image sequences is now routinely applied in clinical and research work. The clinical advantages offered by this approach have been discussed in several reports.(10–12) The primary application is the improved visualization of regions of the heart and circulation opacified by X-ray contrast material during angiographic and angiocardiographic examinations. More complex techniques are being developed for improved functional analysis based on digitized angiograms. Technically, the digital techniques also potentially offer improved means of acquiring, storing, and handling images when comp…

Digital Acquisition and Processing of Video Angiocardiograms

Angiocardiographic diagnosis is still mainly based on the visual assessment of radiographic projection images recorded on photographic film. Considerable amounts of contrast material have to be selectively injected into the circulation in order to make the regions of diagnostic relevance visible in the superposition of the shadows of tissue and bone structures displayed in these transmission images. In addition, selective angiocardiography requires exact positioning of the catheter, a time-consuming procedure which is not without risk. The processing of the angiographie films obtained is difficult to maintain at a constant high quality level, and this introduces an disadvantageous delay bet…

A Bottleneck Model of Imaging Systems for Digital Angiocardiography

Some ten years ago, the performance of real-time digital subtraction angiocardiography was demonstrated for the first time [1]. Subtraction became in the years after 1980 nearly synonymous with digital angiography [2–4]. This image enhancement technique was certainly very efficient in paving the way for the digital approach to imaging. Relatively simple processors and memory structures could perform subtraction methods with some degree of success. However, even in that early stage, it was clear to many of those involved in the technical developments and in early clinical evaluations that subtraction was only one of many features that would motivate the change from traditional film technique…

American College of Cardiology/ European Society of Cardiology international study of angiographic data compression phase III

AbstractOBJECTIVESWe sought to investigate up to which level of Joint Photographic Experts Group (JPEG) data compression the perceived image quality and the detection of diagnostic features remain ...

Langzeitverlauf über 10 Jahre nach Ballondilatation bei stabiler und instabiler Angina pectoris

OBJECTIVE To assess the cardiac status of patients ten years after percutaneous transluminal coronary artery angioplasty (PTCA). PATIENTS AND METHODS Data of 534 patients (436 men, 98 women; mean age 53.2 +/- 8 years) in whom a PTCA had been performed between 1983 and 1986 were analysed, based on a questionnaire answered 121 +/- 11 months after the initial procedure. At the time of PTCA 184 patients (35%) had unstable angina, 350 (65%) stable angina. RESULTS 116 patients (63%) with unstable angina and 164 (47%) with stable angina had at least one cardiac event after the initial PTCA (repeat PTCA, bypass operation, myocardial infarction, death). None of these events occurred in 68 patients (…

Short-and long-term outcome after PTCA in patients with stable and unstable angina

Acute results and follow-up data over a period of 36 months after attempted PTCA in 406 patients with stable angina and 202 patients with unstable angina are reported. The rate of acute complications (death, myocardial infarction and bypass grafting (CABG) amounted to 1.5% in stable and 6.4% in unstable patients (P less than 0.005). Within the first week after PTCA a significantly lower percentage (1.7% vs 10.4%) of cardiac events (death, myocardial infarction, CABG and repeat PTCA) was observed in the stable group (P less than 0.001). During a 12-month follow-up period, another 16.3% of the patients in the stable group and 30.7% of unstable patients suffered a new cardiac event (P less tha…