[Indirect criteria of coronary reperfusion and permeability in patients with acute myocardial infarction who have received thrombolytic therapy].

OBJECTIVE

To evaluate the value of some indirect reperfusion signs (IRS) as markers of coronary artery patency in patients (PTS) with acute myocardial infarction (AMI) submitted to intravenous (IV) thrombolytic therapy (TT).

DESIGN

Retrospective study, with analysis of the sensibility (S), specificity (SP) and predictive value (PV) of three IRS: 1. Pain and ST resolution in the first three hours; 2. Peak CK in the first 13 hours; 3. accelerated idioventricular rhythm (AIVR) in the first three hours.

SETTING

Coronary Care Unit (CCU) of the Santo António Hospital and Hemodynamic Laboratory of the S. João Hospital, Oporto.

PATIENTS

Sixty seven PTS (mean age 53.4 +/- 10.6 years) with confirmed AMI, 62 male and five female, 34 with anterior and 33 with inferior infarction, TT started in the first three hours of the beginning of symptoms in 34 PTS and from three to six hours in 33 PTS, all submitted to coronary angiography in the hospital setting (7.6 +/- 5.9 days after AMI).

INTERVENTIONS

IV administration of 1,500,000 U of streptokinase (SK) in 47 PTS and 30 U of APSAC in 20 PTS, preceded by 200 mg IV prednisolone and oral 100 mg acetilsalicylic acid, and followed by IV heparin therapy. Continuous electrocardiographic monitoring, and serial 12 leads ECG and enzymatic assays (at start and 1, 3, 7, 13 and 25 hours of TT). Analysis of the correlation of the three IRS (isolated and in association) with coronary artery patency (TIMI 2 or 3).

MEASUREMENTS AND RESULTS

The total patency rate was 79.1%; there was no statistically significant difference with regard to AMI location, time of symptoms onset (0-3 vs 3-6 hours) or thrombolytic agent (SK vs APSAC). The first and second IRS had a high S and a low SP; together S = 79.2%, SP = 64.3% and PV = 89.4%. The third IRS with the first and/or the second one had a low S (about 25%) but SP and PV of 100%. The coronary patency rate of PTS without IRS was always greater than 50%.

CONCLUSIONS

The analysed IRS although not very reliable are useful when considered in association. It is possible to assess PTA with high probability of reperfusion if AIVR is present. The absence of IRS does not exclude coronary artery patency. There is still missing more reliable no-invasive reperfusion markers.