title: Alterations in calcium levels of coronary sinus blood during coronary arteriography in the dog.
abstract: Intracoronary administration of contrast materials causes myocardial depression which is related to serveral physiochemical properties of the contrast solution. The role of variations in ambient calcium ions (Ca++) in mediating this effect was evaluated in 19 anesthetized dogs. Sodium meglumine diatrizoate caused decreases in left ventricular peak systolic pressure (LVPSP),-12.6 +/- 3.2%, and dp/dt at a left ventricular pressure (LVP) of 40 mm Hg, -14.3 +/- 4.1%. The total calcium (Cat) decreased from 10.2 +/- 0.2 to 6.5 +/- 0.2 mg%, while Ca++ decreased from 4.6 +/- 0.1 mg% to 2.3 +/- 0.7 mg%. In the presence of systemic hypocalcemia the myocardial depressant actions of this contrast materials were accentuated. Intracoronary administration of contrast material with added Ca++, calcium sodium meglumine metrizoate, caused no myocardial depression. Total calcium decreased only slightly (10.2 +/- 0.2 to 9.1 +/- 0.2 mg%), while Ca++ increased (4.8 +/- 0.1 to 5.1 +/- 0.2 mg%. During systemic hypocalcemia, the calcium metrizoate compound induced increases in LVPSP and dp/dt/LBP40. Thus, contrast materials caused myocardial depression which, at least in part, was related to reduction of ambient calcium through a dilutional and binding action. The addition of Ca++ to monomeric contrast materials reversed the myocardial depressant action and produced a transient rise in ambient Ca++.
mesh_terms: D000818:Animals; D002118:Calcium / Q000097:blood*; D017023:Coronary Angiography; D003974:Diatrizoate Meglumine; D004285:Dogs; D004492:Edetic Acid; D006333:Heart Failure / Q000209:etiology; D006439:Hemodynamics / Q000187:drug effects; D006996:Hypocalcemia / Q000209:etiology; D009200:Myocardial Contraction; D010424:Pentobarbital
chemical_list: D003974:Diatrizoate Meglumine; D004492:Edetic Acid; D010424:Pentobarbital; D002118:Calcium