[Effects of the new cardiotonic agent TA-064: serial computer-assisted analyses of pressure-volume relations and online myocardial 02 consumption].
According to investigations conducted in Japan, TA-064 is a new cardiotonic agent, which is also effective orally. We analyzed computer-assisted alterations of pressure-volume relations serially and of MVO2 online (Bretschneider) during TA-064 influence in 16 patients with congestive cardiomyopathy: LV-function of 7 patients was only moderately decreased (group A) and in 9 patients massively (group B).


RESULTS
1) TA-064, 8 micrograms/kg/min, i.v. had positive inotropic effects in both groups and induced mean maximal delta% changes at about the 5th minute of infusion as follows: LVSWI + 65% and 47%; DP/DTmax + 61% and 59%; LV-efficiency + 62% and 53%; MVO2 + 31% and + 11% (p less than 0.05). 2) TA-064, 20 mg p.o. induced serum levels (A: 23.8 +/- 12 and B: 26.4 +/- 20 ng/ml) corresponding to the effects with the dosages 1-2 micrograms/kg/min, i.v. (p greater than 0.05), thus implying that significant changes in LV-function require higher p.o. dosages. 3) TA-064 i.v. on the 6th day of exposure to the medication produced less LV-function improvement than on day 1 (p greater than 0.05).


CONCLUSIONS
In both groups A and B TA-064 improves LV-function primarily via increased contractility, without toxic side effects. For a more complex definition of the efficiency and mechanism of cardiotonic agents, the validity and importance of using on-line MVO2 assessment and analysis of serial pressure-volume relations is stressed.
D000328:Adult; D001794:Blood Pressure / Q000187:drug effects*; D001810:Blood Volume / Q000187:drug effects*; D002302:Cardiac Output / Q000187:drug effects; D002311:Cardiomyopathy, Dilated / Q000188:drug therapy*; D002316:Cardiotonic Agents / Q000097:blood / Q000627:therapeutic use*; D003201:Computers; D004305:Dose-Response Relationship, Drug; D004983:Ethanolamines / Q000097:blood / Q000627:therapeutic use*; D006333:Heart Failure / Q000188:drug therapy*; D006339:Heart Rate / Q000187:drug effects; D006801:Humans; D008297:Male; D008875:Middle Aged; D009200:Myocardial Contraction / Q000187:drug effects; D009206:Myocardium / Q000378:metabolism; D009862:Online Systems / Q000295:instrumentation; D010101:Oxygen Consumption / Q000187:drug effects*
D002316:Cardiotonic Agents; D004983:Ethanolamines; C037293:denopamine
Wirkungen des neuen Kardiotonikums TA-064: Serielle computerassistierte Analyse von Druck-Volumen-Beziehung und on-line MVO2-Bestimmung.