Experimental models of complete heart block.

Methods of creating experimental complete heart block developed since 1883 are reviewed in detail. The three most commonly used techniques at present are: (I) Thoracotomy, atriotomy and ligation of the A-V bundle. (II) Thoracotomy and injection of a chemical into the A-V node or bundle. (III) Injection of a chemical through a transvenous catheter into the node or bundle. The results in different species, complications, and variations in procedure are discussed. The bibliography provides a comprehensive index of work performed in animals with experimental complete heart block. We produced complete heart block in sixteen pigs but subsequently eleven died during Stokes-Adams attacks. Pigs have not been used previously as models of heart block for experimental purposes and prophylactic pacing appears mandatory in this species.