Deterioration in peak systolic velocity is closely related to ischaemia during angioplasty: a vectorcardiographic and tissue Doppler imaging study

We tested the hypothesis that the extent of signs of ischaemia detected by vectorcardiography (VCG) during elective coronary angioplasty (percutaneous transluminal coronary angioplasty: PTCA) is related to systolic and diasto lic myocardial velocities, as determined by tissue Doppler echocardiography . A total of 15 patients undergoing PTCA (12 men/three women; age 61 +/- 9 years), without prior myocardial infarction and with an election fraction o f > 50%, were included. The balloon inflation was repeated three times, wit h minimum intervals of 2 min between inflations. Tissue Doppler echocardiog raphy was performed. in an apical two- or four-chamber view, before and at the end of each inflation. Peak systolic velocity, time-to-peak systolic ve locity (TTP), peak early (E-m) and late (A(m)) diastolic velocities, the E- m/A(m) ratio and jsovolumic relaxation time were measured in the basal segm ents of the left ventricle. VCG recordings were carried out during the whol e procedure. ST vector magnitude (ST-VM) and ST change vector magnitude (ST C-VM) were monitored. The total duration and area of each VCG change during inflation were calculated for each patient. Isovolumic relaxation time, pe ak E-m and A(m) values and the E-m/A(m) ratio did not change significantly during inflation. Peak systolic velocity decreased (6.7+/-2.0 to 5.3 +/- 1. 9 cm/s; P < 0.001) and TTP increased (157 +/- 60 to 192 +/- 60 ms; P<0.01) during inflation. Both STC-VM rime (r = -0.68, P<0.01) and STC-VM area (r = -0.68, P < 0.01) were related to peak systolic velocity during inflation. STC-VM time was also related (r = 0.55, P < 0.05) to the difference in peak systolic velocity during compared with before inflation. ST-VM was less cl osely related to peak systolic velocity. Thus the duration and degree of is chaemia, as measured by VCG, are related to peak systolic velocity in the b asal segments of the left ventricle.