Differential Diagnosis for Sudden Onset Tachycardia
- Single most likely diagnosis:
- Supraventricular Tachycardia (SVT) - This is a common cause of sudden onset tachycardia, especially in a young adult with no prior history of heart disease. The symptoms of SVT can include palpitations, shortness of breath, and sometimes dizziness or lightheadedness, which align with the patient's presentation.
- Other Likely diagnoses:
- Anxiety or Panic Attack - The onset of symptoms after lunch could be related to anxiety or a panic attack, which can cause tachycardia and feelings of wooziness.
- Dehydration or Electrolyte Imbalance - Especially if the patient had a large or heavy meal, dehydration or an electrolyte imbalance could contribute to tachycardia.
- Caffeine or Nicotine Intoxication - Recent consumption of caffeine or nicotine could lead to an increase in heart rate.
- Do Not Miss (ddxs that may not be likely, but would be deadly if missed.):
- Cardiac Tamponade - Although less likely, cardiac tamponade is a life-threatening condition that can cause tachycardia and should not be missed.
- Pulmonary Embolism (PE) - A PE can present with sudden onset tachycardia and should be considered, especially if there are other symptoms such as chest pain or shortness of breath.
- Hypovolemic Shock - Severe dehydration or blood loss could lead to tachycardia and should be promptly identified and treated.
- Rare diagnoses:
- Pheochromocytoma - A rare tumor of the adrenal gland that can cause episodic tachycardia and hypertension.
- Thyrotoxicosis - An excess of thyroid hormones can lead to tachycardia, among other symptoms.
- Arrhythmogenic Right Ventricular Cardiomyopathy (ARVC) - A rare heart condition that can cause life-threatening arrhythmias, including tachycardia.