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The Authors studied correlations between angiocardiography and changes of R wave amplitude (delta R) during effort in 113 patients. They showed coronarographic evidence: 69 with stenosis greater than or equal to 70% of at least one major coronary vessel and 44 with no significant lesions. delta R values greater or equal than 0 were considered as pathologic. delta R appeared greater than or equal to 0 in 8 of 14 patients (57%) with single stenosis, 4 (28%) with abnormal wall motion (AWM). delta R increase or unchanged in 26 of 31 (84%) patients with double stenoses, 25 of them (81%) with AWM. delta R was greater than or equal to 0 in 22 of 24 (92%) with triple stenoses. In subjects with milk coronary artery disease (CAD) R wave increased or unchanged in 47% (19/44). Pathologic changes of R wave are highly frequent in CAD patients, especially in those with severe impairment. These changes, however, are not specific or costant because they appeared enough frequently in subjects with normal doronary vessels, and, moreover, R wave may decrease also in CAD patients with severe impairment. The Authors consider that evidence of delta R values greater than or equal to 0 may not be considered as a sign of CAD, but it must be evaluated with the other data showed by ergometric tests.

New ecgraphic criteria has been proposed to improve diagnostic availability of R wave changes (delta R) and algebra summation of delta R and ST segment depression (delta RST) in comparison to the criterion of ST depression (ST). The AA. considered as a positive test for a diagnosis of coronary artery disease (CAD): delta R and delta RST values greater than or equal to 0. In 69 patients with stenosis, 75% of at least one major coronary vessel, delta RST showed correct diagnosis in 87% of cases, R in 81% and ST in 73%. RST sensitivity was better than that of ST (P = 0,02). In 44 patients with normal coronaries delta RST was able to correct diagnosis in 52% of cases, delta R in 57% and ST in 73%. ST specificity was better than that of delta RST (P = 0,04). Predictive accuracy was comparable for the three criteria. In normal healthy subjects everyone with an exercise test negative for CAD, with ST analysis, delta R and delta RST was 0 in 16% of cases. New ecgraphic criteria, also showing a better sensitivity in comparison with ST segment analysis, have a worsened specificity. The Authors do not consider these methods a significant improvement in ecgrahic evaluation of exercise test.