Importance of early recanalization of the occluded coronary artery in acute myocardial infarction for preservation of left ventricular function.
Ninety-two patients with acute myocardial infarction, treated with intracoronary thrombolysis within 3 h from the onset of ischemic symptoms, were studied with coronary arteriography and left ventriculography. These examinations were repeated after 2 to 4 weeks to assess the importance of duration of ischemia on recovery of regional and global left ventricular pump function. Patency was achieved acutely and maintained at control angiography in 73 patients (87%), who were subdivided into three groups according to duration of ischemia before reperfusion: group 1 (29 patients): revascularized within 3 h; group 2 (22 patients): revascularized between 3 and 4 h; group 3 (22 patients): revascularized after 4 h. Patency was acutely achieved, but not maintained at control angiography in 11 patients (group 4), while thrombolysis was unsuccessful in eight patients (group 5). In group 1 there was a significant reduction in the number of hypokinetic segments (P less than 0.001) and a significant increase in mean percentual area change of hypokinetic segments (P less than 0.001) and in global ejection fraction (P less than 0.001). A still significant, but less evident improvement in these parameters was also seen in group 2 (P less than 0.05, P less than 0.01, P less than 0.01 respectively). Insignificant changes, with only occasional improvements were observed on group 3, while a tendency toward deterioration was found in group 4. A clear and significant (P less than 0.001) worsening of local and global ventricular function was detected in group 5. Our results indicate a significant inverse relationship between duration of ischemia and left ventricular functional improvement. Particularly, the first 3 to 4 h after onset of ischemic symptoms are critical for preservation of left ventricular function (group 1 and 2). Reperfusion after 4 h (group 3) is only rarely associated with improvement of ventricular motion. The importance of very early pharmacological thrombolysis and of maintenance of coronary patency is stressed.
Valente
M
M
Divisione di Cardiologia, Università di Trieste, Italy.
Klugman
S
S
Niccoli
L
L
Ferrari
R
R
Terrosu
P
P
Camerini
F
F
Ibba
G V
GV
Visioli
O
O
D000368:Aged; D000792:Angiography; D006328:Cardiac Catheterization; D003327:Coronary Disease / Q000188:drug therapy*; D003328:Coronary Thrombosis / Q000150:complications / Q000188:drug therapy*; D005260:Female; D005343:Fibrinolytic Agents / Q000627:therapeutic use*; D006352:Heart Ventricles / Q000503:physiopathology; D006801:Humans; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000209:etiology / Q000503:physiopathology*; D013997:Time Factors
D005343:Fibrinolytic Agents