to assess the mechanisms underlying the beneficial action of nitrates , we further investigated 13 patients with increased coronary reserve ( group 1 ) and five with fixed coronary reserve ( group 2 ) by the exercise response to isdn and verapamil , the changes in left ventricular volumes after isdn and verapamil , the ecg response to intravenous ergonovine , and the changes in coronary stenosis severity following intravenous ergonovine and intracoronary nitrates .
C0022252
isdn
C0028125
nitrates