Late (one month) reversible ischaemia after primary coronary occlusion treated with recombinant tissue plasminogen activator (rTPA)

Abstract

The incidence of reversible ischaemia was assessed four weeks after primary coronary occlusion in 36 patients who had not required earlier revascularisation after randomisation to receive rTPA (n = 19) or placebo (n = 17). Coronary arteriography was performed at three weeks and thallium scintigraphy with dynamic stress testing at four weeks. Patients were followed for one year without planned intervention in the absence of symptoms. Managing physicians remained blinded to thrombolytic therapy. Patency rate of the infarct related artery at three weeks was greater after rTPA (rTPA 16, placebo 9; p = 0.04). Reversible perfusion defects within infarct related artery territory occurred with similar frequency in both treatment groups (rTPA 7, placebo 8). Multivessel disease was frequent (rTPA 11, placebo 12) but associated with a low incidence of reversible perfusion defects outside infarct related artery territory (rTPA 3, placebo 2). Thallium scintigraphy identified six of seven patients requiring subsequent revascularisation (sensitivity 86%, specificity 59%, negative predictive value 94%). Dynamic stress testing was positive for reversible ischaemia in 28% (rTPA 6, placebo 4) and identified two patients requiring revascularisation (sensitivity 29%, specificity 72%, negative predictive value 81%). The greater patency rate achieved with rTPA at three weeks after primary coronary occlusion was not associated with a significantly greater incidence of reversible perfusion defects at four weeks in patients who had not required prior revascularisation. The absence of reversible perfusion defects at four weeks was associated with a low incidence of revascularisation procedures during one year follow-up.