Repolarization parameters in patients with acute ST segment elevation myocardial infarction treated with primary percutaneous coronary intervention with respect to predischarge ST-T pattern: a preliminary study.
BACKGROUND
Negative T wave and lack of ST segment elevation in predischarge ECG in ST-segment elevation myocardial infraction (STEMI) patients are given as markers of good prognosis. Repolarization duration, especially its late part (TpeakTend - TpTe), likewise ST-T patterns, is related to local post-myocardial infarction myocardial attributes. We analyzed the differences in QT parameters in STEMI patients with negative or not-negative T wave pattern in predischarge ECG.


METHODS
The data from 83 STEMI patients (LVEF > 45%, first MI, one-vessel disease) who underwent successful percutaneous coronary intervention of infarct-related coronary artery (TIMI 3 flow) were collected. According to ST-T patterns in predischarge ECG, the cohort was divided into two groups: 38 patients with persistent ST elevation and/or non-negative T wave pattern (STT+), and 45 patients with negative T wave, without ST elevation (STT-). QT, QTpeak, and TpTe intervals were obtained from 5 consecutive beats of sinus rhythm 60-70 bpm between 6 a.m. and 8 a.m. from Holter recording, corrected to the heart rate (HR) with Bazett's formula.


RESULTS
The study groups did not differ in gender, age, or treatment. No true antiarrhythmics were given. Both QTc and TpTec were longer in STT+ patients: 459 +/- 26 ms vs. 440 +/- 25 ms, p = 0.01 and 108 +/- 10 ms vs. 96 +/- 11 ms, p = 0.000015, respectively. Prolongation of late repolarization was found both in anterior and inferior infarction.


CONCLUSIONS
STEMI patients who underwent successful percutaneous coronary intervention of infarct-related coronary arteries and demonstrated persistent ST elevation, without negative T wave at hospital discharge, had a longer repolarization duration, especially the late phase of it. Further studies are necessary to assess the prognostic value of this finding.
Szydło
Krzysztof
K
1st Department of Cardiology, Medical University of Silesia, Katowice, Poland. krzysztofszydlo@onet.eu
Wita
Krystian
K
Trusz-Gluza
Maria
M
Zawada
Karolina
K
Piecuch
Anna
A
Kulach
Anna
A
Kucz
Ewa
E
Tyrka
Anna
A
Kornacka
Iga
I
Trams-Stawowska
Patrycja
P
Pieda
Grzegorz
G
D000200:Action Potentials; D000368:Aged; D015906:Angioplasty, Balloon, Coronary; D003324:Coronary Artery Disease / Q000150:complications / Q000503:physiopathology / Q000628:therapy*; D015716:Electrocardiography, Ambulatory; D005260:Female; D006329:Heart Conduction System / Q000503:physiopathology*; D006339:Heart Rate; D006801:Humans; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000209:etiology / Q000503:physiopathology / Q000628:therapy*; D010351:Patient Discharge; D010865:Pilot Projects; D011237:Predictive Value of Tests; D013318:Stroke Volume; D013997:Time Factors; D016896:Treatment Outcome; D016277:Ventricular Function, Left