[Hemodynamic effects of diltiazem in the subacute stage of myocardial infarct treated by thrombolysis]

G Ital Cardiol. 1987 May;17(5):450-5.
[Article in Italian]

Abstract

Since Ca++-overloading is a major problem after myocardial reperfusion we studied the effects of Diltiazem on the left ventricular diastolic function in the early days following coronary thrombolysis. Twelve patients who had myocardial reperfusion by intracoronary urokinase in acute myocardial infarction were admitted to the study. Previous infarct, cardiogenic shock or late thrombolysis (greater than 4 h from symptoms onset) were exclusion criteria. All subjects were evaluated at control cardiac catheterization 5-8 days after the acute ischemia. Simultaneous left ventricular angiography and high-fidelity pressure recordings by means of a tip-micromanometer and angiographic catheter were performed at rest and after intravenous Diltiazem administration (16 mg over 2' + 0.008 mg/Kg/min). Indexes of myocardial relaxation and early ventricular filling were impaired at rest but improved significantly after Diltiazem (Tab. II). Isovolumic relaxation period fell from 92 +/- 8 msec to 77 +/- 12 msec (p less than .01), T constant of isovolumic pressure decay decreased from 61 +/- 7 msec to 55 +/- 7 msec (p = ns), first-third of filling rate increased from 64 +/- 7% to 79 +/- 6% (p less than .01). On the other hand, indexes of left ventricular compliance were altered after coronary reperfusion (left ventricular end-diastolic compliance 17 +/- 13 mmHg-1. 10(-3), modulus of chamber stiffness .045 +/- .008) but but did not change after calcium-blocker therapy. In conclusion, post-thrombolysis diastolic function is severely impaired at rest, probably because of raised intracellular Ca++ and delayed asynchronous relaxation. Diltiazem improves energy-dependent early diastole, but does not affect ventricular compliance.

Publication types

  • English Abstract

MeSH terms

  • Adult
  • Aged
  • Coronary Circulation*
  • Diastole / drug effects*
  • Diltiazem / pharmacology*
  • Fibrinolysis*
  • Humans
  • Male
  • Middle Aged
  • Myocardial Contraction / drug effects*
  • Myocardial Infarction / drug therapy*
  • Myocardial Infarction / physiopathology
  • Systole / drug effects

Substances

  • Diltiazem