Anaphylactic reactions affecting the human heart.

We have investigated a large number of patients, most of whom suffered from severe systemic anaphylactic or anaphylactoid reactions during the induction of anaesthesia; the term 'anaphylactoid' was restricted to patients who had no history of prior exposure. Cardiac dysrhythmia (including severe bradydysrhythmia), which was documented by electrocardiography, was one of the principal manifestations, and in one case there was evidence of myocardial ischemia as well.