Relationship between myocardial viability and the predischarge electrocardiographic pattern in patients with first anterior wall acute myocardial infarction.
BACKGROUND
The assessment of residual viability in the infarcted area after an acute myocardial infarction is relevant to subsequent management and prognosis.


OBJECTIVE
The aim of this study was to investigate the correlation between myocardial viability after an acute anterior myocardial infarction (AMI) as assessed by low dose dobutamine stress echocardiography (LDDSE) and the electrocardiographic patterns of ST segment and T wave abnormalities at the end of the first week of the acute event.


METHODS
Sixty-nine consecutive patients (51 men, 18 women, mean age+/-standard deviation=57+/-11 years) who admitted to our clinic due to a first episode of transmural AMI were included in this study. Two-dimensional echocardiography was performed to all patients during rest and low dose dobutamine administration at the end of the first week of admission (7+/-2 days). Patients were classified into four groups according to ST segment and T wave morphology: group A, ST elevation < or =0.1 mV and negative T waves; group B, ST elevation < or =0.1 mV and positive T waves; group C, ST elevation > or =0.1 mV and negative T waves and group D, ST elevation > or =0.1 mV and positive T waves.


RESULTS
Myocardial viability was detected more often in patients with isoelectric ST segments (22/24, 92%) than those with elevated ST segments (21/45, 47%) (P<0.001). Similarly patients with negative T waves had myocardial viability more frequently compared to those with positive T waves (32/45, 71% vs. 11/24, 46%, P<0.01). Seventeen (94%) of 18 patients in group A and 5 (83%) of six patients in group B had viable myocardium (P>0.05). Myocardial viability was found in 15 (56%) of 27 patients in group C and six (33%) of 18 patients in group D (P<0.01). As a marker of viable myocardium, isoelectricity of ST segment was specific (92%) but only moderately sensitive (51%), with a 92% positive predictive accuracy and a poor (53%) negative predictive value. T wave negativity was less specific but more sensitive than isoelectricity of ST segment for myocardial viability.


CONCLUSIONS
The presence of isoelectric ST segment and negative T wave indicates a high probability of myocardial viability. However, absence of these electrocardiographic patterns does not exclude the presence of viable myocardium.
Atak
Ramazan
R
Turkiye Yuksek Ihtisas Hospital, Department of Cardiology, Ankara, Turkey. hratak@yahoo.com
Turhan
Hasan
H
Senen
Kubilay
K
Ileri
Mehmet
M
Yetkin
Ertan
E
Ozbakir
Cemal
C
Demirkan
Deniz
D
D000368:Aged; D025401:Echocardiography, Stress; D004560:Electricity; D004562:Electrocardiography; D005260:Female; D006352:Heart Ventricles / Q000000981:diagnostic imaging / Q000503:physiopathology; D006801:Humans; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000000981:diagnostic imaging / Q000503:physiopathology*; D009206:Myocardium / Q000473:pathology*; D010351:Patient Discharge; D011237:Predictive Value of Tests; D012680:Sensitivity and Specificity; D013223:Statistics as Topic; D013318:Stroke Volume / Q000502:physiology