NSTEMI Hastalarında Perkütan Koroner Girişim Öncesi ve Sonrası QTc Aralığı, Elektriksel Aks ve ST-T Değişikliklerinin Tanısal Değeri

Abstract

Giriş: Elektrokardiyografi, kardiyovasküler semptomların değerlendirilmesinde esastır. ST yükselmesiz miyokart enfarktüsünde (NSTEMİ) dinamik EKG değişiklikleri klinik kararlara yardımcı olabilir. Bu prospektif çalışma, NSTEMI hastalarında perkütan koroner girişim öncesi ve sonrasında QTc aralığı, elektriksel aks, ST segment çökmesi ve T dalga morfolojisindeki değişikliklerin tanısal ve prognostik değerini değerlendirmiştir. Yöntemler: Bu çalışmaya NSTEMI tanılı 100 yetişkin hasta prospektif olarak dahil edildi. Demografik veriler, tedaviler ve seri EKG'ler (başvuru anında ve PKI sonrası) analiz edildi. QTc aralığı, QRS aksı, ST segment çökmesi ve T dalga negatifliği karşılaştırıldı. İstatistiksel analizlerde parametrik ve non-parametrik testler kullanıldı. Bulgular: Tüm hastalarda PKG öncesi, PKG sonrasına kıyasla anlamlı bir QTc aralığı uzaması tespit edildi (p<0,001). Koroner tutulum lokalizasyonuna göre: LAD (%34), Cx (%17) ve RCA (%14) en sık etkilenen damarlar olurken, olguların %21'inde anjiyografik olarak anlamlı bir lezyon saptanmadı. Medikal tedavi uygulanan grupta QTc değişikliği 0-20 msn aralığında sınırlı kalırken, koroner obstrüksiyonu olan grupta belirgin bir QTc uzaması (>20 msn) gözlemlendi (p<0,001). Aks değişiklikleri lezyon lokalizasyonu ile korele idi: RCA tutulumunda sağa deviyasyon (p<0,01), LAD/Cx tutulumunda sola deviyasyon (p<0,01). ST segment çökmesinde anlamlı bir fark bulundu (p<0,05). Sonuç: Bu çalışma, NSTEMI'de QTc aralığı ve elektriksel aks değişikliklerinin tanısal değerini doğrulamaktadır. İlk EKG'de 20 msn'yi aşan bir QTc uzaması, kritik koroner patolojiye işaret edebilir. Aks deviasyon paterni de etkilenen damarın belirlenmesine yardımcı olabilir. Bu parametreler atipik olgularda tanı sürecini hızlandırabilir.

Keywords

• NSTEMI
• QTc Aralığı
• Perkütan Koroner Girişim
• Kalp Aksı

Diagnostic value of QTc interval, electrical axis, and ST-T changes before and after percutaneous coronary intervention in NSTEMI patients

Abstract

Electrocardiography (ECG) is a fundamental tool in the evaluation of patients presenting with suspected acute coronary syndrome. In non-ST-elevation myocardial infarction (NSTEMI), dynamic ECG changes may provide additional information regarding ischemia-related electrical alterations. This study aimed to evaluate the association of changes in QTc interval, electrical axis, ST-segment depression, and T-wave morphology with coronary angiographic findings. A total of 100 adult patients diagnosed with NSTEMI were prospectively included. Demographic characteristics, treatment strategies, and serial 12-lead ECGs obtained at presentation and approximately 4 hours after coronary angiography were analyzed. QTc interval, QRS axis, ST-segment depression, and T-wave negativity were assessed. Appropriate parametric and non-parametric statistical tests were used. Percutaneous coronary intervention (PCI) was performed in patients with significant lesions. QTc interval was significantly shorter after angiography compared with baseline (461.2±55.5 ms vs. 404.4±24.9 ms, p<0.001). Coronary angiography revealed obstructive disease in 79% of patients. All medically managed patients demonstrated ΔQTc ≤20 ms, whereas all PCI patients demonstrated ΔQTc >20 ms. ROC analysis yielded an AUC of 1.00, although this finding was interpreted cautiously due to complete separation. A significant reduction in ST-segment depression was observed after angiography (p<0.05), whereas no significant change was found in T-wave negativity. Dynamic QTc changes may be associated with angiographically significant coronary artery disease in NSTEMI patients. Since ΔQTc requires both pre- and post-procedural ECG measurements, it should not be considered a pre-procedural diagnostic marker for identifying obstructive coronary artery disease. The observed QTc shortening may reflect post-revascularization electrical recovery in NSTEMI patients. Although ΔQTc showed complete separation in this cohort, the >20 ms threshold was identified post hoc and should be considered exploratory rather than clinically validated.

Keywords

• NSTEMI
• QTc Interval
• Percutaneous Coronary Intervention
• Cardiac Axis

References

1. Čulić V, Eterović D, Mirić D, Silić N. Symptom presentation of acute myocardial infarction: influence of sex, age, and risk factors. Am Heart J. 2002;144(6):1012-7.
2. Mackay MH, Ratner PA, Johnson JL, Humphries KH, Buller CE. Gender differences in symptoms of myocardial ischaemia. Eur Heart J. 2011;32(24):3107-14.
3. Patel MR, Li S, Lopes RD, Jones WS, Pacheco CM, Al-Khalidi HR, et al. Global variation in ST depression patterns and outcomes in acute coronary syndromes. J Am Coll Cardiol. 2020;75(12):1455-67.
4. Zhang L, Wang Y, Chen X, Ding H, Liu Y, Li J, et al. Global prevalence and prognostic significance of ST-segment depression. Heart. 2021;107(14):1153-61.
5. Bonnemeier H, Hartmann F, Wiegand UK, Bode F, Katus HA, Richardt G, et al. Course and prognostic implications of QT interval and QT interval variability after primary coronary angioplasty in acute myocardial infarction. J Am Coll Cardiol. 2001;37(1):44-50.
6. Cruz-Aragón G, Márquez MF, Cueva-Parra A, Rodríguez DA, Matadamas Zárate P. Corrected QT interval and GRACE score relationship in patients with non-ST-segment elevation myocardial infarction. Arch Peru Cardiol Cir Cardiovasc. 2022;3(3):132-8.
7. Gadaleta FL, Llois SC, Sinisi VA, Lapuente AR, Raimondi EC, Tajer CD, et al. Corrected QT interval prolongation: a predictor of cardiovascular risk in non-ST elevation acute coronary syndrome patients. Rev Esp Cardiol. 2008;61(6):572-8.
8. Gadaleta FL, Llois SC, Lapuente AR, Batchvarov VN, Kaski JC. Prognostic value of corrected QT interval prolongation in patients with unstable angina pectoris. Am J Cardiol. 2003;92(2):203-5.

9. Mann T, Moses A, Yesaulov A, Shapira A, Finkelstein A, Halkin A, et al. QT interval dynamics in patients with ST-elevation myocardial infarction. Front Cardiovasc Med. 2023;10:103676.
10. Ogino K, Fukugi M, Hirai S, Iwasaka T, Inada M. The usefulness of exercise-induced QRS axis shift as a predictor of coronary artery disease. Clin Cardiol. 1988;11(2):101-4.
11. Hegge AA, Tuna N, Burchell HB. Electrocardiographic changes in selective coronary arteriography. Circulation. 1966;33(4):585-94.
12. Collet JP, Thiele H, Barbato E, Barthélémy O, Bauersachs J, Bhatt DL, et al. 2020 ESC Guidelines for the management of acute coronary syndromes in patients presenting without persistent ST-segment elevation. Eur Heart J. 2021;42(14):1289-367.
13. García-Lledó A, Rodríguez-Martín S, Tobías A, et al. Prognostic value of QTc prolongation in patients with acute coronary syndrome: a systematic review and meta-analysis. Rev Esp Cardiol (Engl Ed). 2022;75(6):482-491.
14. Bazett HC. An analysis of the time-relations of electrocardiograms. Heart. 1920;7:353-370. Kenigsberg DN, Khanal S, Kowalski M, Krishnan SC. Prolongation of the QTc interval is seen uniformly during early transmural ischemia. J Am Coll Cardiol. 2007;49(12):1299-1305.
15. Fridericia LS. Die Systolendauer im Elektrokardiogramm bei normalen Menschen und bei Herzkranken. Acta Med Scand. 1920;53:469-486.
16. Thygesen K, Alpert JS, Jaffe AS, Chaitman BR, Bax JJ, Morrow DA, et al. Fourth Universal Definition of Myocardial Infarction. Eur Heart J. 2019;40(3):237-269.