STkäyrää

STkäyrää is a Finnish term that translates to "ST curve" or "ST segment curve." In the context of electrocardiography (ECG), it refers to the graphical representation of the ST segment, which is the portion of the ECG tracing between the end of the S wave and the beginning of the T wave. This segment represents the period when the ventricles are completely depolarized and before repolarization begins.

The shape and position of the ST segment are crucial in diagnosing various cardiac conditions. Deviations from the normal isoelectric line (the baseline) can indicate myocardial ischemia (reduced blood flow to the heart muscle) or injury. An elevated ST segment, often seen in acute myocardial infarction, suggests that the heart muscle is being damaged. Conversely, a depressed ST segment can be indicative of ischemia that is not causing infarction, or it can be a sign of other issues such as electrolyte imbalances or certain medications.

The analysis of the STkäyrä involves looking for elevation, depression, and specific morphology changes like concavity or convexity. These changes are interpreted by healthcare professionals in conjunction with other ECG findings and the patient's clinical presentation. Variations in the STkäyrä can be subtle or pronounced, and their significance is often determined by the lead in which they appear and the degree of deviation. Understanding the STkäyrä is a fundamental aspect of interpreting ECGs for a wide range of cardiovascular assessments.