JM, a 62-year-old male with an unknown past medical history, is brought to the emergency department (ED) by emergency medical services (EMS) personnel for sudden onset of palpitations. His vital signs on admission are: blood pressure 110/60 mm Hg, heart rate 155 beats/minute with a rhythm of atrial fibrillation with rapid ventricular response, respiratory rate 26 breaths/minute, and temperature 37.8°C. The bedside TEE displays an LVEF of 30% and no visible thrombus in the atria. The patient has no allergies, takes no medications, and has a history of heart failure. The decision is made to utilize a rate control therapy for this patient. What is the most appropriate treatment strategy for rate control in this patient with non-valvular atrial fibrillation?

A 48-year-old female patient weighing 70 kg, with a history of Supraventricular Tachycardia (SVT), arrives at the Emergency Department (ED) complaining of chest pains and a rapid heart rate. She is currently not on medication. Her vital statistics show a Blood Pressure of 130/80 mmHg, a Heart Rate of 220 beats per minute, an O2 saturation of 100% on room air, and a Respiratory Rate of 12 breaths per minute. The patient’s last SVT episode occurred two years ago. The attending physician decides to administer adenosine to regulate her heart rate. What is the right initial dose of adenosine to give her?

A 32-year-old man with a known history of palpitations and dizziness presents to the emergency department. Despite his efforts to control these symptoms with deep breaths and neck massages, they have escalated in severity over several hours. His current vital signs indicate a blood pressure of 60/30 mmHg and a heart rate of 220 beats per minute. An EKG reveals regular narrow-complex tachycardia (SVT). Based on his hemodynamic status and current symptoms, what is the most appropriate intervention?

A 31-year-old woman without any notable medical history reports to the emergency department. She is experiencing shortness of breath and palpitations that began rapidly when she bent down to pick up her son. She self-reported daily multivitamin and oral contraceptive use. On examination, her vital stats are: blood pressure – 128/82 mmHg, pulse – 161/min, and respirations – 16/min. An ECG reveals a regular narrow-complex tachyarrhythmia, indicative of AV nodal reentrant tachycardia (AVNRT). Carotid sinus massage and Valsalva maneuvers are performed; however, symptoms persist. What is the appropriate next step in management?

A 65-year-old male with a past medical history of hypertension, currently on amlodipine, presents to the emergency department with complaints of shortness of breath and new onset palpitations. On arrival, his vitals are as follows: BP 90/62 mm Hg, HR 165 beats/min, RR 26 breaths/min, and temperature 38.9oC. A 12-lead ECG indicates a narrow complex tachycardia with a regular rhythm, diagnosed as AV nodal reentrant tachycardia (AVNRT). Despite unsuccessful attempts with adenosine 6 mg and 12 mg (given twice) and vagal maneuvers, he continues to be symptomatic with persistent hypotension. What is the most appropriate next step in the management of this patient’s condition?