What immediate action should be taken for a patient with symptomatic bradycardia from heart block?

Transcutaneous pacing is the correct action to take for a patient experiencing symptomatic bradycardia due to heart block. This intervention provides temporary support to restore an adequate heart rate and improve cardiac output when the heart cannot do so on its own. Symptomatic bradycardia can manifest as dizziness, fatigue, hypotension, or even syncope, and immediate pacing serves to stabilize the patient until a more permanent solution is arranged.

Other options involve more passive or longer-term management strategies that are not suitable for immediate response. For instance, referring the patient to cardiology is important for further evaluation and potential intervention, but it does not address the acute symptoms of bradycardia. Similarly, administering digoxin is not appropriate in this context, particularly as it can further slow heart rate in bradycardic patients and may complicate the heart block situation. Starting a cardiac stress test is also inappropriate, as it can provoke further complications in a patient already presenting with bradycardia. Therefore, transcutaneous pacing is the most effective and urgent intervention to manage the situation safely.