Cardiovascular Dynamics in Complete Heart Block at Various Heart Rates

Thirteen patients with complete atrioventricular block resulting from coronary disease were studied. In seven the diagnosis of coronary disease was established by the presence of typical history and electrocardiographic and enzymatic findings compatible with an acute infarction. Of the remaining six cases, three had a typical history of angina pectoris. In three cases there was no history of myocardial infarction or angina pectoris, and the diagnosis of coronary disease was suspected by the appearance of heart block above age 60 in the absence of any other possible etiologic factor that might be responsible for the establishment of the block. Exercise studies were performed in eight cases. Right heart catheterization was performed under local anesthesia prior to implantation of a permanent cardiac pacemaker. A no.-6 bipolar electrode catheter * 1 was introduced into the antecubital vein and advanced to the apex of the right ventricle. Another no.-7 Lehman catheter was introduced into the cephalic vein and advanced to the right atrium and right ventricle. Cardiac output was determined by the indicator-dilution technic with indocyanine t (Cardio-