Comparison of three methods of measuring liver blood flow.

Liver blood flow was measured by dynamic 99Tcm-sulfur colloid accumulation and indocyanine green disappearance in 5 subjects, and by 99Tcm-sulfur colloid accumulation and 133Xe-wash-out in 7 subjects. Results obtained by the 99Tcm-sulfur colloid and indocyanine green methods were closely comparable, whereas the flow values estimated by the two isotope methods did not correlate well.

Tests for ischaemia and left ventricular function in young patients with effort-induced chest pain.

The type of angina pectoris was determined in 47 women and 27 men aged 40 or less who then underwent quantitative left cineventriculography, coronary arteriography and atrial pacing test with determination of lactate concentrations from arterial and coronary sinus blood samples. The 29/74 patients with atypical angina and no narrowings on coronary arteriography (Group I) gave no pathological atrial pacing tests but 9 had pathological lactate tests. Group II consisted of 27/74 patients with typical angina but normal coronary arteriography. In these the atrial pacing test was pathological in 20 and the lactate test in 11. Coronary narrowings of 50% or more were found in 18/74 patients (Group III), who all had pathological pacing tests but only 9 pathological lactate tests. No statistical differences could be elicited between diagnostic groups in the quantitative evaluation of left ventricular function and it could be regarded as normal in 42/74 patients. The left ventricular mass index exceeded the control level in 6 patients in Group I and in 10 patients in Group II who all had a net lactate production upon pacing. The end-diastolic volume index was above control level in 11 patients in Group II, in whom the ST depression in pacing test was the only finding indicating ischemia. The hoop stress values exceeded the control level in both of these subgroups. In Group III 7 patients had a high left ventricular mass index and 4 a billowing mitral leaflet. The changes observed suggest disturbed functioning of left ventricle.

Effect of aortic valve replacement on the left ventricle. A ciné-angiographic evaluation.

Heart catheterization and quantitative left ventricular ciné-angiography data on thirty patients with aortic vlave disease were analyzed pre-operatively and 12 months after insertion of a Björk-Shiley tilting disc valve. The pre-operative and postoperative data were compared and also with a control group of 22 patients with no organic heart disease. According to the functional NYHA classification, 14 patients had improved, 14 were unchanged and 2 had deteriorated. Regurgitation had been totally corrected in 27 patients, and the high or moderate pressure gradient between the left ventricle and aorta had been reduced, but the valve itself caused a gradient of 5 to 35 mmHg. The pre-operatively abnormal pump function, hypertrophy, dilatation and impaired myocardial function had all become markedly more normal. The most obvious changes were an improvement in stroke work relative to end-diastolic volume and myocardial mass (p less than 0.001) and reductions in end-diastolic volume (p less than 0.001), pump power (p less than 0.001) and myocardial mass (p less than 0.001). Aortic valve replacement seems to be an appropriate procedure in cases where the left ventricular performance and haemodynamics are sufficiently disturbed.

[Ejection as index of left ventricle function]. / Le travail d'éjection comme indicateur de la fonction du ventricule gauche.

Quantative left ventricular cineangiography performed 1 year post operatively in 24 patients with prosthetic aortic valves demonstrated significant reductions in the end diastolic volume and myocardial mass. Cardiac work was only slightly reduced. When cardiac work was compared to the end diastolic volume or myocardial mass results suggestive of myocardial hypercontractility were obtained. However when cardiac work was normalised simultaneously with the end diastolic volume and myocardial mass, the index so obtained was lowered pre operatively but did not differ significantly from normal values after operation. This index with seems to reflect the clinical evolution appears to be of greater value than the other indices used for determining left ventricular function. The reducted function of the hypertrophied myocardium was shown to be reversible during the 1 year post operative period.

Ergospirometry and coronary arteriography in young patients with angina pectoris or atypical chest pain.

A bicycle ergospirometric test was performed on 57 women and 26 men of age 40 or less in combination with coronary arteriography for angina pectoris or chest pain atypical for ischaemia severe enough to affect their working capacity. Nine men and 14 women had angina pectoris with coronary artery narrowings of 50% or more (Group I) and 5 men and 22 women had angina pectoris without obvious coronary artery narrowings (Group II). This means an incidence for coronary changes of 64% for men and 38% for women for angina pectoris. Group III consisted of 12 men and 21 women with a chest pain atypical for ischaemia and without coronary artery narrowings. Minor changes were found on angiographic examination in some patients. Four men and 11 women could not do the ergospirometry adequately. The patients with coronary artery narrowings had a lower maximal oxygen consumption than the others, even though only the mean values for the women showed a statistically significant difference. They also had lower maximal heart rates and their total work and maximum load were lower. The highest proportion of ST segment depressions of 0.5 mm or more was also found in the same patients. The pressure rate product did not show any clear difference with regard to the patient groups or the ST segment changes. As a purely diagnostic tool ergospirometry does not give more information about possible ischaemia in cases of chest pain than a routine upright bicycle test, but for following up patients with angina pectoris and evaluating treatment it gives valuable data about working capacity.

Angina pectoris in young patients: clinical appraisal and evaluation by exercise, atrial pacing, and myocardial lactate metabolism.

Young patients with a symptom complex of angina pectoris constitute a problematic group in medicine. Many of them require a detailed investigation. By combining electrophysiologic and metabolic measurements with dynamic clinical experiments, one can distinguish with great probability between normal and pathological findings. Exercise ECG, atrial pacing and simultaneous sampling of blood from artery and coronary sinus were undertaken in 57 patients aged 40 or less. Although the patients were selected according to a history of effort angina, results were normal in four and in seven other only one test was pathological. The sensitivity was highest in atrial pacing (78%) and somewhat lower in exercise ECG (75%) and lactate extraction (67%). The specificity of the tests in series was about 53%. Concordant results made a diagnosis of ischemic heart disease highly probable. Discrepancies and probably false negative results in individual cases are evident. The need for angiographic evaluation of coronary arteries and left ventricular function is clear. The stepwise advance from the usual physical examination to more demanding investigations provides a possibility of classifying the patients according to the needs of an accurate medical appraisal.

Lactate dehydrogenase isozymes of chick embryo: response to variations of ambient oxygen tension.

Incubation of chick embryos in an hypoxic environment causes an ncrease in the proportion of tissue lactate dehydrogenase (LDH) made up of subunit M, whereas incubation in aerobic conditions decreases the proportional amount of subunit M. The variation of ambient oxygen tension does not change the total LDH activity. These results support the hypothesis that oxygen or oxidative metabolites have an effect on the synthesis of the subunit peptides.