xiv INTISARI Interval Tpeak-Tend sebagai Prediktor

INTISARI
Interval Tpeak-Tend sebagai Prediktor Kejadian Kardiovaskular Mayor pada Infark
Miokardium Akut dengan Elevasi Segmen ST selama
Perawatan di Rumah Sakit
Latar Belakang: Infark miokardium akut dengan elevasi segmen ST (IMA-EST) merupakan
kondisi gangguan perfusi regional akibat oklusi total arteri koroner yang mengakibatkan
perubahan potensial aksi miokardium. Kondisi ini terjadi secara inhomogen antara lapisan
epikardial, endokardial, dan sel M sehingga terjadi peningkatan dispersi repolarisasi transmural.
Dispersi repolarisasi dapat menyebabkan aritmia dan disfungsi ventrikel kiri berupa gagal
jantung dan syok, yang akhirnya berakibat kematian. Dispersi repolarisasi secara noninvasif
dapat diukur dengan interval Tpeak-Tend (Tp-Te) pada elektrokardiografi (EKG) yang
menggambarkan perbedaan akhir repolarisasi epikardium dan akhir repolarisasi sel M.
Penelitian ini bertujuan untuk mengetahui apakah interval Tp-Te dapat memprediksi kejadian
kardiovaskular mayor (KKM) yang terdiri atas aritmia ventrikel, kematian, gagal jantung, dan
syok kardiogenik selama perawatan di rumah sakit.
Metode Penelitian: Studi kohort retrospektif dilakukan untuk mengambil data EKG pasien
IMA-EST saat admisi di UGD RSUP Dr. Sardjito sejak Januari hingga Juli 2016. Interval TpTe dihitung dari durasi antara puncak gelombang T hingga perpotongan garis tangensial
gelombang T dan isoelektris. Interval Tp-Te dibagi 2 kelompok berdasarkan nilai potong kurva
sensitivitas-spesifisitas. Luaran KKM dan faktor yang mempengaruhinya dicatat. Uji chi
square dipakai untuk menganalisi hubungan interval Tp-Te dan KKM, sedangkan uji regresi
logistik dipakai untuk uji multivariat.
Hasil: Dari 172 pasien, terdapat 79 subjek memiliki interval Tp-Te>120 mdet dan 93 subjek
dengan interval Tp-Te<=120 mdet. Subjek yang mengalami KKM pada kelompok dengan
interval Tp-Te>120 dibandingkan <=120 adalah 23 vs 13 (RR 2,08, IK95% 1,13-3,85,
p=0,025). Uji multivariat menunjukkan interval Tp-Te konsisten meningkatkan risiko KKM
dgn OR 2,83 (IK95% 1,26-6,36, p=0,012).
Simpulan: Pemanjangan interval Tp-Te meningkatkan risiko kejadian kardiovaskular mayor
secara independen pada pasien IMA-EST selama perawatan di rumah sakit.
Kata kunci: interval Tpeak-Tend, infark miokardium akut dengan elevasi segmen ST, kejadian
kardiovaskular mayor
xiv
ABSTRACT
Tpeak-Tend Interval as a Predictor of Inhospital Major Cardiovascular Events in STElevation Myocardial Infarction
Background: ST-Elevation Myocardial Infarction (STEMI) occurs when there is a disturbance
in the regional perfusion due to total occlusion of coronary artery which electrophysiologically
causes changes in myocardial action potential. This condition occurs heterogenously between
epicardium, endocardium, and M-cell which then cause an increased dispersion of transmural
repolarization. Repolarization dispersion may cause arrhythmia and left ventricle dysfunction
in the form of heart failure or shock, which ultimately may lead to death. Repolarization
dispersion can be measured non-invasively with Tpeak-Tend (Tp-Te) interval from
electrocardiography (ECG) examination which shows differences between the end of
epicardium and M-cell repolarization. This study was aimed to describe whether Tp-Te interval
can predict inhospital major cardiovascular events (MACE) consists of ventricular arrhythmia,
death, heart failure, and cardiogenic shock.
Methods: Retrospective cohort study was conducted to collect ECG records of patients with
STEMI when admitted to emergency department of RSUP Dr.Sardjito in January - July 2016.
Tp-Te interval was measured from duration between the peak of T-wave and the intersection
of tangential line of T-wave and isoelectric. Tp-Te interval was divided by two groups based
on cut off value of sensitivity-specificity curve. Major cardiovascular events as an outcome and
confounding factors were recorded. The chi-square test was used to analyze the association
between Tp-Te interval and MACE, while logistic regression was used for multivariate
analysis.
Results: From 172 patients, we gathered 79 subjects who have Tp-Te interval >120 msec and
93 subjects who have Tp-Te interval <120 msec. Subjects with MACE in group of Tp-Te
interval >120 compared to <120 are 23 vs 13 (RR 2.08, 95% CI 1.13-.3.85, p=0.0.25). The
multivariate analysis showed that Tp-Te interval consistently increased the risk of inhospital
MACE with OR 2.83 (95%CI 1,26-6,36, p=0,012).
Conclusion: Prolonged Tp-Te interval increased the risk of inhospital major cardiovascular
events independently in patients with STEMI.
Keywords: Tpeak-Tend, ST elevation myocardial infarction, major cardiovascular events
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