Which of the following is a contraindication for using Adenosine?

Adenosine is primarily used in the treatment of certain types of supraventricular tachycardia (SVT), but there are specific contraindications that must be considered before administration. The correct contraindication in this case is the presence of second-degree or third-degree A-V block.

In patients with A-V block, adenosine can exacerbate the condition by further interrupting the conduction through the atrioventricular node. This can lead to prolonged asystole or severe bradycardia, which could be dangerous to the patient. Therefore, adenosine should be avoided in these patients to prevent potentially life-threatening arrhythmias.

While uncontrolled hypertension, asthma, and acute coronary syndrome may pose risks associated with adenosine use, they are not absolute contraindications. Uncontrolled hypertension can be monitored and managed without adenosine, and while adenosine can cause bronchospasm in asthmatic patients, it is not an absolute contraindication. In acute coronary syndrome, the use of adenosine requires caution but is not contraindicated as long as there is careful monitoring and appropriate clinical judgment.