Effect of submaximal exercise on fibrinolytic activity in ischaemic heart disease.

Abstract

Fibrinolytic activity and platelet adhesiveness are normal in cases of angina pectoris and healed myocardial infarction, whereas fibrinolytic activity is diminished in acute myocardial infarction. Exercise increases fibrinolytic activity in normal people but the effect on it of submaximal exercise in patients with ischaemic heart disease is not known. Resting platelet adhesiveness and fibrinolytic activity were determined in 20 patients suffering from ischaemic heart disease and eight healthy controls. Both groups were then subjected to submaximal exercise on a motor-driven treadmill. The ST segment of the electrocardiogram and the heart rate were monitored during exercise by an on-line digital computer. Fibrinolytic activity determinations were repeated immediately after exercise. There was a significant increase in fibrinolytic response in both groups but it was significantly less in the ischaemic groups (36.2%) compared with the controls (55.9%) (P < 0.01).The ST segment depression was 2-3 mm in the ischaemic group and 0-52 mm in controls-also a significant difference (P <0O01). There was no correlation, however, between the ST change and thefibrinolytic response. A diminished response in the ischaemic group may favour their predisposition to thrombotic episodes.

The Effect of Exercise on Thrombin and Plasmin Generation in Middle-Aged Men

“…The use of the euglobulin clot lysis time, treadmill exercise, and greater fibrinolytic responses may in part explain the discrep ancy in the results between the present study and that of Khanna et al [8],…”

“…Dynamic tests of ex vivo plasma fibrino lytic potential using venous occlusion (fibrin plate) and submaximal exercise (euglobulin lysis time) have revealed that abnormalities of fibrinolysis occur more commonly in men with coronary artery disease [5,8], However, we have been unable to show any differences in such ex vivo fibrinolytic potential be tween men with and without coronary dis ease in the present study, and a similar study on the plasma fibrinolytic responses to bicy cle exercise has confirmed our results [11]. The use of the euglobulin clot lysis time, treadmill exercise, and greater fibrinolytic responses may in part explain the discrep ancy in the results between the present study and that of Khanna et al [8],…”

“…Although factor VIII and fibrinogen are the two coagulation factors most closely associ ated with coronary disease [1,6,7], abnor malities of fibrinolysis have also been de scribed in such patients [5,[8][9][10][11], Fibrino lytic potential ex vivo is known to increase with exercise [12], Fibrinolytic activity in vivo can now be measured by radioimmu noassay (RIA) of fibrin(ogen) fragment Bp15_ 42 (a product of plasmin digestion) in plas ma, while RIA of fibrinopeptide A (FPA) gives a sensitive measure of thrombin gener ation. By measurement of these small pep tides simultaneously the balance between fi brinolysis and coagulation can be evaluated [13].…”

Severity of Coronary Artery Disease and Basal Fibrinolysis

“…Our study, therefore, fails to provide any support for the association of basal fibrinolysis with established coronary artery disease. We did not study the fibrinolytic capacity which may be impaired in coronary artery disease [5][6][7][8][9], due in part of increased levels of tissue plasminogen activator inhibitor [4,5,9].…”

“…While abnormalities of fibrinolysis, both at rest [1][2][3][4][5] and following exercise or venous occlusion [5][6][7][8][9], have been recorded in pa tients with coronary artery disease, the large epidemiological, prospective studies of fibri nolysis in middle-aged men have so far failed to show a relationship between defective fi brinolysis and the development of cardio vascular events [10,11 ]. A role for fibrinoly sis in the development of coronary artery disease is, therefore, unproven.…”