Differential Diagnosis for Chest Tightness and Shortness of Breath

• Single Most Likely Diagnosis
  • Exercise-induced asthma: This is the most likely diagnosis given the patient's symptoms of chest tightness, shortness of breath, and coughing during and after exercise, along with a decrease in FEV1 after exercise. The spirometry results showing a decrease in FEV1 after exercise also support this diagnosis.
• Other Likely Diagnoses
  • COPD (Chronic Obstructive Pulmonary Disease): Although the patient is an ex-smoker, which increases the risk for COPD, the spirometry results do not show a significant obstructive pattern at rest. However, the symptoms and history could still suggest early or mild COPD.
  • GERD (Gastroesophageal Reflux Disease): GERD can cause symptoms of chest tightness and shortness of breath, especially if the patient has reflux during exercise or at night, which could explain the nocturnal shortness of breath.
• Do Not Miss Diagnoses
  • CAD (Coronary Artery Disease): Although less likely given the patient's age and the nature of the symptoms, CAD must be considered, especially in a patient with a history of smoking. The symptoms of chest tightness and shortness of breath could be indicative of angina or a myocardial infarction, which would be life-threatening if missed.
• Rare Diagnoses
  • Vocal Cord Dysfunction: This condition can mimic asthma and cause symptoms of shortness of breath and wheezing, especially during exercise. However, it is less common and would require further evaluation to diagnose.
  • Cardiac Conditions Other Than CAD: Conditions such as hypertrophic cardiomyopathy or arrhythmias could cause exertional symptoms and must be considered, especially if there's a family history or other suggestive findings.