Diagnostic Approach to Cough, Palpitations, Flushing, and Tachycardia
Critical Life-Threatening Diagnoses to Exclude First
- The American College of Cardiology recommends considering supraventricular tachycardia (SVT) in patients with regular paroxysmal palpitations with abrupt onset and termination, which may be diagnosed with a 12-lead ECG during tachycardia 2
- The American College of Cardiology suggests that SVT alone does not explain cough or flushing, making this an incomplete diagnosis for the full symptom complex 4, 3
Secondary Considerations After Excluding Neuroendocrine Causes
- Pertussis infection causes prolonged paroxysmal cough lasting 4-6 weeks or longer, often called "the hundred day cough", and diagnosis requires PCR or culture during catarrhal phase (first 2 weeks); serologic testing for IgG/IgA antibodies if presenting later 1
- Upper Airway Cough Syndrome (UACS) can cause chronic cough with sensation of postnasal drip, though "silent" UACS exists without typical symptoms, and trial of first-generation antihistamine plus decongestant for 1-2 weeks is diagnostic and therapeutic 5, 6
- Gastroesophageal Reflux Disease (GERD) causes chronic cough and can mimic upper airway symptoms, and empiric proton pump inhibitor therapy for 8-12 weeks is appropriate if reflux symptoms present 6
Diagnostic Algorithm
- If patient is on ACE inhibitor, discontinue immediately as this causes chronic cough in up to 20% of patients; resolution typically occurs within 1-4 weeks 6
- The American College of Cardiology recommends obtaining 12-lead ECG to capture rhythm during palpitations if possible, and look for pre-excitation (delta waves) suggesting accessory pathway 3, 2
- Avoid treating isolated symptoms (antitussives for cough, beta-blockers for tachycardia) before establishing underlying diagnosis, and do not assume SVT explains all symptoms—the combination with flushing demands broader investigation 6, 4, 3