[Chronic intermittent urokinase therapy: anti-ischemic and hemodynamic effects]

Long-term intermittent urokinase therapy has been developed for patients with severe coronary artery disease and refractory angina pectoris. This therapeutic approach is predominantly effective at the microcirculatory level based on a combination of rheologic and fibrinolytic effects; furthermore, plaque regression seems to be a possible mechanism. Patients with refractory angina pectoris are characterized by severe coronary artery disease without a therapeutic option for conventional revascularization procedures, only slight impairment of left ventricular systolic function and hyperfibrinogenemia, which results in further enhancement of myocardial ischemia due to microcirculatory impairment of blood flow. In this article data on the anti-ischemic effectiveness as well as first results on the impact of this therapeutic approach on hemodynamics are described. A dose-response study, which compared 3 x 50,000 IU with 3 x 500,000 IU urokinase three times a week over a treatment period of 12 weeks demonstrated subjective as well as objective antiischemic effectiveness. Only patients who were treated with 500,000 IU per injection achieved marked increases in exercise capacity, while some patients in the low-dose group presented even with a deterioration of exercise performance. First hemodynamic studies could not show marked changes of systolic parameters, either at rest or during exercise. But a decrease of pulmonary capillary wedge pressure at rest after treatment with 500,000 IU per injection indicates an improvement of diastolic function as a result of enhanced myocardial perfusion. Echocardiographic measurements of transmitral Doppler flow in 21 patients with end-stage coronary artery disease demonstrated normalization of early and late diastolic filling rates in most cases. These changes were accompanied by a reduction of clinical signs of heart failure. Long-term intermittent urokinase therapy is a valuable approach as it not only improves quality of life during the actual treatment period but by the persistence of therapeutic effects following the cessation of therapy.