In left bundle branch block (LBBB) thallium-201 myocardial scintigraphy frequently reveals septal abnormalities in the absence of coronary artery disease (CAD) and gives rise to "false-positive" results in patients with suspected CAD. It has not yet been clarified which pathophysiological mechanism is responsible for these perfusion abnormalities. A total of 66 patients with constant LBBB were investigated with 201Tl or technetium-99m-hexakis-methoxyisobutylisonitrile (MIBI), 62 underwent coronary angiography. Of 12 patients without left anterior descending artery (LAD) or right coronary artery (RCA) stenoses, 11 had a reversible septal activity deficit after 201Tl stress injection, whereas 20 of 22 patients without relevant CAD showed a constant stress/rest septal deficit using MIBI. Regarding patients with significant LAD and/or RCA stenoses, both radio-pharmaceuticals almost always showed a "reversible" septal deficit: with 201Tl in 15 of 16 individuals and with MIBI in 14 of 15. In 12 patients 201Tl was reinjected at rest. In those who had LAD or RCA stenoses (n = 5), early septal activity uptake after stress injection was poorer than that after rest injection; in the absence of CAD (n = 7), septal stress uptake corresponded with that of rest injection. It is concluded that septal perfusion abnormalities in LBBB and the absence of CAD are characterized by an exercise-independent reduction of septal blood flow per mass of viable myocardium and that stress/rest injection protocols of myocardial perfusion tracers are able to differentiate between LBBB with and without CAD.

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In 52 patients with exercise angiography (12 normals, 31 with coronary heart disease, 9 with congestive cardiomyopathy) exercise ECGs were examined for R-wave changes. An increasing R-wave amplitude was found an insensitive sign of ischemia in patients with coronary heart disease (sensitivity 29%, specificity 81%). Sensitivity and specificity of the observed ST depression in this study were 83% and 71%, respectively, as reported by others. There was no positive correlation between the changes in the R-wave amplitude and left ventricular end-diastolic volume during exercise, thus there was no proof of the existence of the so-called Brody effect in humans.

In 1975/76 the risk of hepatitis from human clotting preparations (fibrinogen, prothrombin complex) prepared from pooled plasma was studied prospectively in patients who had undergone open-heart surgery with cardiopulmonary bypass. Of 247 patients 25 (10%) developed hepatitis postoperatively, while of 17 recipients of plasma-fraction concentrates 12 developed hepatitis (71%). Even taking into account other potential risk factors this rate of hepatitis is statistically significant. It demonstrates that even with the most modern screening methods it is not possible to produce clotting preparations from "large pool" human plasma which is free of hepatitis risk, unless additional virus-inactivating measures are taken.

A history of exercise-induced chest pain or even typical angina pectoris combined with normal coronary arteries is usually described with terms like small vessel disease or syndrome X [2, 5]. The aim of this paper is to study the hemodynamics at rest, and with exercise, and the outcome of patients with this syndrome.