ST segment elevations with straight (horizontal, upsloping, or downsloping) or convex ST segment strongly suggest acute transmural ischemia (Figure 1 A). Concave ST segment elevations, on the other hand, are much less likely to be caused by ischemia (Figure 1 B). This is noted in both North American and European guidelines.

The ST segment may be displaced upwards (ST segment elevation) or downwards (ST segment depression). The term ST segment deviation refers to elevation and depression of the ST segment. The magnitude of ST segment deviation is measured as the height difference (in millimeters) between the J point and the PR segment. Refer to Figure 13 for examples.

Concave ST segment elevations, on the other hand, are less likely to be caused by ischemia (Figure 6B). This is noted in both North American and European guidelines. However, a concave ST segment does not rule out STEMI, it only reduces the probability of STEMI. Figure 6. Differential diagnosis of ST elevations. Other causes of ST segment ...

The ST segment may be either elevated or depressed (in relation to the PR segment). This is referred to as ST segment elevation and ST segment depression. The T-wave may diminish in amplitude ( flat T-waves ), become negative ( T-wave inversion ) or even increase markedly in amplitude ( hyperacute T-wave ).

The straight ST segment can be either upsloping, horizontal or (rarely) downsloping. Non-ischemic ST segment elevations are typically concave (Figure 16, panel B). Concave ST segment elevations are extremely common in any population; e.g ST segment elevation in leads V2–V3 occurs in 70% of all men under the age of 70.

2025年1月18日 · 2017 ESC Guidelines for the management of acute myocardial infarction in patients presenting with ST-segment elevation: The Task Force for the management of acute myocardial infarction in patients presenting with ST-segment elevation of the European Society of Cardiology (ESC) Borja Ibanez, Stefan James, Stefan Agewall, Manuel J Antunes, Chiara ...

ST segment elevation may occur in V1–V3. ECG in severe hyperkalemia (Potassium >7,5 mmol/L) Previously mentioned ECG changes become more pronounced. The QRS complex becomes wider. Refer to Figure 1. If the hyperkalemia is very severe, the QRS complex may fuse with the T-wave and form a so-called sine wave. This is certainly alarming because ...

Normal (physiological) ST segment depressions occur during physical exercise. These ST segment depressions have an upsloping ST segment. The depression in the J 60 point is usually <1 mm and it resolves rapidly once the exercise is stopped. Some experts believe that these ST segment depressions represent a benign form of subendocardial ischemia.

Figure 2. Measurement of ST segment depression during exercise stress testing. Types of ST segment depressions. ST segment depressions may be characterized as (1) J point depressions, (2) upsloping ST depressions, (3) horizontal ST depressions, or (4) downsloping ST depressions. These types are illustrated in Figures 3 and 4.

As in adults, ST-depression with horizontal or downsloping ST-segment is more alarming than upward sloping ST depressions. Upward sloping ST-depressions are normal at high heart rates. ST-elevations may occur in children, especially adolescents. ST-elevations are most common in precordial leads (V2-V6) and may reach 2 mm (measured in the J point).