Two successive electrocardiograms of an old male with acute myocardial infarction: What on earth was going on?

Abstract A 68‐year‐old male complained of a sudden 2‐h chest pain accompanied by dizziness and diaphoresis. His consciousness lost several times because of ventricular fibrillation attack. Emergent CAG showed proximal left anterior descending (LAD) occlusion, but two previous successive electrocardiograms established diagnoses of non‐ST‐elevation myocardial infarction (NSTEMI) and STEMI respectively, indicating that the patient had experienced acute subtotal occlusion of proximal LAD to total occlusion of the left main coronary trunk (LMT). It is vital to identify de Winter pattern associated with proximal LAD lesion in view of the potential circulatory collapse, fatal arrhythmias and sudden cardiac death from it.

A 68-year-old man complained of a sudden 2-h chest pain accompanied by dizziness and diaphoresis. The patient had a history of smoking. His consciousness lost upon arrival at the emergency room. Electrocardiogram (ECG) revealed ventricular fibrillation, which was immediately defibrillated. An urgent ECG was then performed (Figure 1), and his blood pressure was 77/51 mmHg. Ventricular fibrillation recurred a few minutes later, and another ECG was redone after defibrillation ( Figure 2). The second ECG was performed 9 min after the first. The patient was immediately given aspirin (300 mg), ticagrelor (180 mg) orally, and unfractionated heparin (4000 u) intravenously. Coronary angiography (CAG) was performed an hour after the second ECG, showing total occlusion of the proximal left anterior descending (LAD) (thrombolysis in myocardial infarction [TIMI] flow = 0) without collateral circulation (Figure 3).
A drug-eluted stent was deployed in the proximal LAD, and blood flow was restored (TIMI flow = 3). Two additional cardiac arrests occurred before CAG, both dealt with defibrillation. Emergency cardiac troponin I level was 0.029 ng/ml (normal, <0.04 ng/ml) and peaked at 12.289 ng/ml after percutaneous coronary intervention (PCI). 12-lead ECG (Figure 4) was performed on the first day after PCI. Subsequent echocardiogram showed an ejection fraction of 50%. The patient's condition was stable.
Based on the first two consecutive ECGs (Figures 1 and 2), what was the diagnosis?
Notably, in the absence of right bundle branch block (RBBB), the increased amplitude of R waves in leads V 1 , V 2 (R/S > 1 in V 2 ), as well as the disappearance of "septal Q waves" in leads V 5 , V 6 , demon- In 2008, de Winter et al. (2008 found that in a small number of patients, when the proximal LAD, as a culprit artery, presented either subtotal occlusion or total occlusion with well-developed collateral circulation, the ECG showed NSTEMI pattern with ST-segment showing a 1-to 3-mm upsloping depression at the J point in leads V 1 to V 6 , followed by tall, positive symmetrical T waves and with 1-to 2-mm ST-elevation in aVR. This ECG pattern is now referred to as de Winter pattern in which the ST-segment F I G U R E 1 ECG performed after the first defibrillation F I G U R E 2 ECG was performed 9 min later than the initial ECG usually slightly depresses in inferior leads. In the present case, the first ECG was consistent with de Winter pattern and resulted from the proximal LAD lesion. According to the comparison between the ECG in Figure 1 and that in Figure 4 involved. At the same time, it is rare that the ST-segment depression in V 1 and the ST-segment elevation in V 2 -V 6 exhibit beat-to-beat alternation. The evident electrical alternans reflects spatiotemporal heterogeneity in myocardial repolarization, predicting a higher risk of malignant ventricular arrhythmias (Narayan, 2006).
Although CAG showed total occlusion of proximal LAD, the ECG results indicated that the patient had experienced subtotal occlusion of proximal LAD to total occlusion of the LMT. The reason should be the thrombus increases rapidly within a short time. The lesson from this patient is that de Winter pattern is usually static and persisting, but sometimes, it could change into STEMI pattern associated with occluded proximal LAD and even occluded LMT. All of them are prone to cardiogenic shock and/or cardiac arrest. Therefore, it is vital to identify de Winter pattern accurately and perform PCI timely in view of the potential circulatory collapse, fatal arrhythmias, and sudden cardiac death from it.
The second ECG indicated total occlusion of the LMT, but only proximal LAD occlusion without LCX obstruction was shown in CAG. It may be explained by partial thrombus dissolution due to anti-platelet aggregation and anticoagulation treatments, or mechanical factors associated with multiple defibrillation that had led to the displacement of the thrombus from LMT near the LCX ostium deeply into the proximal LAD.
The large, dominant right coronary artery, restoring blood flow in the LCX, and timely PCI may contribute to the patient's survival and favorable prognosis.

CO N FLI C T O F I NTE R E S T
The authors declare no conflicts of interest.

E TH I C A L A PPROVA L
The study was approved by the Institutional Review Board Committee of The Third Affiliated Hospital of Soochow University, Changzhou City, China.

AUTH O R CO NTR I B UTI O N S
Dr Xiaoqing Wang was responsible for the design and writing of the article. Dr Yongjun Chen and Dr Xiaoyu Yang performed the CAG and PCI on the patient. Dr Ling Yang was responsible for reviewing the article.

DATA AVA I L A B I L I T Y S TAT E M E N T
No data are available.