A 30-year-old female is admitted with fever, elevated WBC, diarrhea, and abdominal pain and found to have C. difficile colitis. The patient complains of palpitations associated with anxiety. The nurse reports the patient's BP is 130/70 with a heart rate of 150 bpm. The EKG is shown in Figure 11-1.
1. What is the best next step?
The EKG reveals SVT with a HR of 150 bpm. The best step to perform next is carotid sinus massage. If there is no response, try intravenous adenosine. Continue to treat the underlying infection as well.
SVT refers to paroxysmal tachyarrhythmias that involve the atria, the atrioventricular (AV) junction, or both. It should be noted that while all of the above terms are technically causes of SVT, clinicians should use the specific diagnosis, when possible, such as atrial flutter and atrial fibrillation with rapid ventricular response.
Most SVTs have a narrow QRS complex on ECG, but SVT with aberrant conduction can produce a wide complex tachycardia that may mimic ventricular tachycardia (VT). These tachycardias commonly occur as a result of a precipitating illness or drug interaction.
Managing SVT is relatively straightforward. If the patient is hemodynamically unstable, proceed to cardioversion. If the patient is hemodynamically stable, treatment includes carotid massage, IV adenosine, beta-blockers, and/or calcium channel blockers.
- Quick recognition of arrhythmias is important and comes with practice and experience.
- Anticoagulation with warfarin has significant risks, so should be reserved for patients with high CHADS2 scores.
- Mortality outcomes are similar for patients with atrial fibrillation who are treated with rhythm control compared with those treated with rate control.
Ahya SN, Flood K, Paranjothi S. Cardiac Arrhythmias. The Washington Manual of Medical Therapeutics. 30th ed. Philadelphia: Lippincott Williams & Wilkins; 2001:153–167.
Cheng A, Kumar K. Overview of atrial fibrillation. In: Zimetbaum P, Saperia G, eds. UpToDate. 2012.
Phang R. Overview of the evaluation and management of atrial flutter. In: Zimetbaum P, Saperia G, eds. UpToDate. 2012.