How does digitalis toxicity present on an EKG?

Digitalis toxicity is commonly associated with specific changes on an EKG that reflect its effects on cardiac electrical activity. One of the hallmark signs of digitalis toxicity is the presence of a characteristic "scooped" appearance of the ST segment, often described as a "hockey stick" configuration. This alteration occurs due to the drug's influence on the myocardial action potential and results in the downsloping of the ST segment after the T wave, which can significantly affect the overall assessment of cardiac rhythm.

Recognizing this EKG change is crucial for clinicians as it can prompt the consideration of digitalis toxicity in a patient who presents with symptoms of toxicity, such as nausea, vomiting, blurred vision, or altered mental status. The "scooped" ST segments are often accompanied by other signs such as bradycardia or a PR interval prolongation, but the unique appearance of the ST segment is a defining feature indicative of digitalis effects.

This understanding allows for a more informed diagnosis and management plan for patients at risk of or exhibiting signs of digitalis toxicity.