The de Winter Pattern as Pre-Anterior ST-Elevation-Myocardial-Infarction. “An Evolution Sequence”: A Case Report

Introduction: The de Winter pattern (dWP) was first described by de Winter and colleagues in 2008 as static pattern associated with anterior myocardial infarction. A recent study showed the evolution sequence of this pattern into typical ST-elevation myocardial infarction (STEMI). This case discussed dWP who present as pre-anterior STEMI. Case Illustration: A-56-year old Male arrived in the emergency room complained chest pain about 3 hours. The patient also complained of diaphoresis, nausea, and fatigue. The patient has a previous history of hypertension. The vital signs were stable with an unremarkable physical examination. The initial electrocardiogram (ECG) revealed sinus rhythm with j-point depression followed by prominent T wave in precordial leads, slight ST-segment elevation in aVR, and loss of precordial R-wave progression. The initial-troponin-T was 31 pg/mL. Follow-up 1-hour after initial ECG showed typical ST-segment-elevation in V1-V4. The patient undergoing thrombolytic, followed by angiography that showed subtotal occlusion in the proximal left anterior descending (LAD) artery, occlusion in the proximal circumflex artery and stenosis in proximal right coronary artery, echocardiography revealed regional wall motion abnormality in the septal and anterior segments and preserved ejection fraction 58%, the patient was discharged after 8-days treated in intensive cardiac care unit. Conclusion: dWP has been shown as static and dynamic pattern in some conditions and associated with acute LAD occlusion. In this case, we showed dWP as early anterior STEMI, recognition of this pattern lead to early reperfusion and better myocardial salvage as anterior STEMI has a poor outcome.

Macro- and microfeatures of Early Cambrian dolomitic microbialites from Tarim Basin, China

The fabrics of microbialites preserved in limestones are generally better than in dolostones. What are the fabrics of the microbialites preserved in heavily dolomitized dolostones? This paper presents an example of a strongly dolomitized Cambrian microbialite profile. The Xiaoerblak Formation (Cambrian Series 2 Stage 3 and lower Stage 4) of the Sugaitblak section in Aksu, Xinjiang Uygur Autonomous Region, China is mainly composed of microbial dolostones. Due to strong alteration by diagenesis, their features, formation and environments have not been fully understood. Here, based on detailed observation on outcrops and thin sections, we show that this formation comprises four kinds of microbialites: laminite, thrombolite, thrombolitic laminite, and Renalcis framestone, in five intervals (Interval I to Interval V). We identified three main types of microbialite fabrics, i.e., clotted fabric, laminated fabric and skeletal fabric, and established a high-resolution vertical evolution sequence of the microbialites. The clotted fabric and the laminated fabric were further divided into subtypes. We found that the original fabrics were mainly affected by dolomitization, recrystallization and dissolution, and the alteration degree of the microbialite fabric is stronger in the lower part of this formation. The laminated fabric has the strongest resistance to diagenesis, followed by the clotted fabric. Based on studies of different rock types and sedimentary structures, we concluded that the sedimentary environment of Xiaoerblak Formation consists of three settings: a) Intervals I to III formed in restricted tidal flat environments, b) Interval IV and the lower part of Interval V in restricted deep subtidal environments, and c) upper part of Interval V in shallowing-up open subtidal environments.