[Effect of sodium nitroprusside and nitroglycerin on the resistance and capacitance system in cardiac surgery interventions]. / Die Wirkung von Natriumnitroprussid und Nitroglycerin auf das Widerstands- und Kapazitätssystem bei kardiochirurgischen Eingriffen.

The whole-body arterial and venous dilating properties of nitroglycerin (NTG) and sodium nitroprusside (SNP) were investigated during extracorporeal circulation and normal circulation in patients undergoing coronary bypass surgery. SNP was found to lower preload and afterload for the time of drug administration. During extracorporeal circulation and normal circulation, an average volume of 340 ml was stored in the capacitance vessels when the mean arterial pressure was lowered for 20 mm Hg. When the reduction in preload was compensated by a volume load (blood transfusions), this resulted in a pure impedance reduction by SNP. NTG showed more complex effects. Even with the continuous infusion of NTG only a short-termed, self-limiting afterload reduction occurred during extracorporeal circulation. During normal circulation, the reduction in preload was more extensive with NTG than with SNP, an average volume of 600 ml was stored in the capacitance vessels when the mean arterial pressure was lowered for 20 mm Hg by NTG. While the volume storage by SNP was reversible after termination of the infusion, this was not the case with NTG, where the volume was stored for 1-2 hours. The volume storage by NTG became smaller with an increased filling of the capacitance system. Additionally, the venous resistance of the cardiopulmonary bypass showed different effects on the volume storage by SNP and NTG. In conclusion, the different effects of NTG and SNP cannot be explained by a single, homogenous compartment model of the peripheral circulation but by affecting two different compartments of the capacitance system.

[Preoperative localization of myocardial areas requiring revascularization in coronary artery disease (author's transl)]. / Zur präoperativen Lokalisation bypass-bedürftiger Myokardregionen bei der koronaren Herzkrankheit.

At the time of preoperative coronary angiography in 44 patients left ventricular angiograms immediately after high frequency stimulation and after administration of nitroglycerin were performed. For interpretation we used the shortening (in percentage) of 8 vertical semi-diameters and of longitudinal axis in biplane angiograms. The data found in 15 healthy persons were used for comparison. Looking at the rate of shortening after high frequency stimulation myocardial areas endangered by hypoxia could be unmasked. By giving nitroglycerin thereafter we were able to differentiate between reversibly and irreversibly damaged areas. In 7 patients this has already been proven by postoperative examination. In preoperatively reversibly damaged myocardial areas no hypokinesis could be observed any more after successful revascularization. In contrast there was no improvement seen in preoperatively irreversibly damaged areas in spite of graft patency. The described preoperative angiography-test allows: 1. to unmask myocardial areas endangered by hypoxia. 2. to differentiate preoperatively between reversibly and irreversibly damaged areas. 3. more precise indication as well as better control of the results of revascularization.

[The regulation of the circulatory system in the early postoperative period after open-heart surgery during physical therapy and orthostatic exercise (author's transl)]. / Postoperatives Verhalten der Herz- und Kreislaufregulation nach Herzoperationen unter Muskelarbeit und orthostatischer Belastung.

17 patients, who underwent open heart procedures, were examined during and after standardized exercises at the first, second and third postoperative day. At 10 defined time intervals the following parameters were measured: arterial blood pressure, right and left atrial pressure and in the pulmonary artery, arterial and venous blood gases and cardiac output by thermodilution. Oxygen consumption and cardiac index were calculated. The results show that the majority of patients after open heart surgery are well able to adjust to additional work load even early postoperatively.

[Effect of isosorbide dinitrate in relation to posture and age]. / Die Wirkung von Isosorbitdinitrat in Abhängigkeit von Körperlage und Lebensalter

Rapid tilting into the 90 degrees upright position after 20 mg ISDN sublingually demonstrates a better orthostatic tolerance of the older group (in spite of a lower cardiac output) in comparison to the younger one. This can be explained by a higher tone of the resistance vessels and a stronger stretch resistance of the arteries of the elastic type (and probably of the veins), which are opposing the hydrostatic effects of orthostasis and guarantee a minor shifting of blood to the lower extremities. The increase of rigidity of the blood vessels with aging declares the better drug resistance of the older group but also points - on the other hand - to the borders of ISDN therapy.

[Reaction of peripheral veins and arteries following administration of beta-active agents. Studies on isoproterenol, propranolol, and practolol]. / Die Reaktion der arteriellen und venösen Gefässperipherie auf beta-aktive Substanzen. Untersuchungen mit Isoproterenol, Propranolol und Practolol

The local effect on veins and arteries of isoprenaline, propranolol and practolol was investigated in the human after intra-arterial application at the forearm. The injection of isoprenaline was followed by a dilatation of the arteries and veins. This effect was inhibited by propranolol, but not by practolol. The results demonstrate, that the peripheral vasoactive beta-stimulatory effect is mediated by so-called beta2-receptors, which were not influenced by a selective beta1-blocking agent like practolol. The results were discussed in respect to their clinical relevance.

[Isosorbide dinitrate in coronary heart disease. Effects of a delayed-action preparation during acute load and in chronic use]. / Zur Wirkung von Isosorbiddinitrat bei der koronaren Herzkrankheit. Effekte einer Langzeitpräparation während akuter Belastung und chronischer Anwendung

The antianginal effectivity of a sustained release isosorbiddinitrate Sorbidilat Retard drug was examined by the number of spontaneous attacks and by ergometry with a constant work load in a double blind trial with cross over technique. An effect on the stress duration, on the ST segment depression, on the "double product", on heart rate, and blood pressure could be proved, which is interpreted as an therapeutic advantage of serum against placebo. The number of spontaneous attacks could be reduced in the verum period significantly. Ergometry every 2 hour after drug adminstration shows an oral effectivity of about 10 hours.

[The effect of oxyfedrine on cardiac performance in coronary patients. Tests using electrocardiographic and metabolic parameters in atrial stimulation]. / Die Wirkung von Oxyfedrin auf die kardiale Belastungstoleranz bei Koronarpatienten

In 17 patients with coronary heart disease the effects of the beta-active agent L-3-(beta-hydroxy-alpha-methyl-phenethyl-amino)-3'-methoxy-propiophenone (oxyfedrine, Ildamen) were proved at rest and during atrial pacing by measurements of coronary venous O2-saturation, myocardial lactate extraction, angina threshold and ST-segment depression. In 88% oxyfedrine had antianginal effectivity with rise in angina threshold (+11%), reduction of ST-segment depression (--48%) and reduction of lactate production(--63%). The rise in coronary venous O2-saturation ("35%) and the electrocardiographic and metabolic reduction of hypoxic reaction indicate the improvement of nutritional coronary flow. Therefore improvement of myocardial O2-balance is derived from the reduced energy requirement by decrease of heart size and ventricular wall tension and the rise of myocardial O2-supply by coronary dilation in spite of the increased energy requirement by ascending contractility. Conclusively the application of oxyfedrine is preferred in coronary heart disease with simultaneous congestive heart failure.

[Electrode problems in pacemaker wearers (experiences with three electrode types) (author's transl)]. / Elektrodenprobleme bei Schrittmacherträgern (Erfahrungen mit 3 Elektrodentypen)

3 types of electrodes (Medtronic 6903, EMT 588, MIP 2000) of 123 patients are examined by following criterial 1. rate of dislocation, 2. development of threshold, 3. time of application. We found: The Medtronic has the smallest rate of dislocation, the lowest range of threshold and is quickly placed in the right ventricle. The rate of dislocation of the EMT 588 is still just acceptable and it also has a sufficient low threshold, but in comparison to the other helical-wire electrodes the disadvantage of being rather difficult to place in the right ventricle. The MIP 2000 has not proved to be useful due to its large rate of dislocation.

[Course of coronary disease. Evaluation of prognosis and progression of coronary insufficiency with atrial pacing and ergometry]. / Verlauf der koronaren Herzkrankheit. Beurteilung der Prognose und Progredienz der Koronarinsuffizienz mit Vorhofstimulation und Ergometrie

Significant reduction of angina threshold (145 Imp./min to 134 Imp./min) and increase of ST-segment depression (0.13 to 0.17 mV) indicating progression of coronary artery disease was seen in 34 subjects studied by atrial pacing at intervals betion (0.22 mV to 0.12 mV) during exercise, which correlated significantly with decrease of heart rate (121 to 110 beats/min), is interpreted as consequence of diminished sympathetic activity and myocardial O(2)-demand. The change of hemodynamic parameters during controlled exercise does not allow evaluation concerning the progress of coronary artery disease, whereas cardiac stress test with atrial pacing is reproducible. There was no difference in relation to reduction of angina threshold between the group after combined longterm medication with nitrate and ss-blocking agent and the control group. Plasma lipid abnormalities were predictive of subsequent reduction of angina threshold. Severe 2 and 3 vessel obstruction was seen more frequently in patients exhibiting reduction of angina threshold. Level of uric acid, obesity, hypertension, age, combination of risk factors, the initially studied myocardial lactate production and angina threshold during exercise and atrial pacing had no predictive value concerning reduction of angina threshold.