Effects of angiographic contrast media on sino-atrial nodal function.
Injection of meglumine diatrizoate (Renografin-76) into the selectively perfused sinus node artery of the dog produces bradycardia which is unaltered by autonomic blockade or by changes in sinus node artery pressure. Contrast agents and other hyperosmolar substances prolong the R-R interval in proportion to their osmolarity. Selective injection of contrast media into other cannulated segments of the coronary tree produces no change in heart rate. Transfemoral arteriography, however, produces bradycardia with both right and left coronary injections. Both direct and reflex sinus node depression occur with coronary arteriography in the dog. Direct effects are mediated by hyperosmolarity.
D000319:Adrenergic beta-Antagonists / Q000494:pharmacology; D000818:Animals; D001285:Atropine / Q000494:pharmacology; D001794:Blood Pressure / Q000187:drug effects; D003973:Diatrizoate / Q000031:analogs & derivatives*; D003974:Diatrizoate Meglumine / Q000494:pharmacology*; D004285:Dogs; D005260:Female; D006339:Heart Rate / Q000187:drug effects*; D008297:Male; D009994:Osmolar Concentration; D010276:Parasympatholytics / Q000494:pharmacology; D012849:Sinoatrial Node / Q000187:drug effects*; D012965:Sodium Chloride; D014783:Viscosity
D000319:Adrenergic beta-Antagonists; D010276:Parasympatholytics; D003973:Diatrizoate; D003974:Diatrizoate Meglumine; D012965:Sodium Chloride; D001285:Atropine