Differential Diagnosis

The patient's symptoms of chest tightness, restlessness, inability to sit still, and lightheadedness, in the context of ADHD and anxiety, suggest a complex interplay of factors. Here's a categorized differential diagnosis:

• Single Most Likely Diagnosis
  • Anxiety Disorder with Somatic Symptoms: The patient's symptoms of chest tightness, restlessness, and lightheadedness are consistent with anxiety-related somatic symptoms. The absence of chest pain, normal echocardiograms, and ECGs, along with the patient's history of anxiety, support this diagnosis. The fact that these symptoms occur in the absence of physical exertion and are not relieved by rest suggests a non-cardiac origin.
• Other Likely Diagnoses
  • Caffeine-Induced Anxiety: The patient's high caffeine intake (24 oz of coffee per day) could exacerbate anxiety symptoms, contributing to the sensations of chest tightness and restlessness.
  • Nicotine Withdrawal or Dependence: The patient's use of nicotine vapes and difficulty stopping could contribute to symptoms of restlessness, anxiety, and potentially chest discomfort.
  • Hyperventilation Syndrome: The feeling of lightheadedness and chest tightness could be related to hyperventilation, which is often seen in individuals with anxiety disorders.
• Do Not Miss Diagnoses
  • Cardiac Arrhythmias: Although the patient has had normal ECGs, it's essential to consider cardiac arrhythmias, such as supraventricular tachycardia (SVT) or atrial fibrillation, which can cause palpitations, lightheadedness, and chest discomfort.
  • Pulmonary Embolism: Although less likely, given the patient's age and lack of other risk factors, pulmonary embolism can cause sudden onset of chest discomfort, shortness of breath, and lightheadedness.
  • Hyperthyroidism: This condition can cause anxiety, restlessness, palpitations, and chest discomfort, making it a crucial diagnosis not to miss.
• Rare Diagnoses
  • Panic Disorder with Cardiophobic Focus: A subtype of panic disorder where individuals experience panic attacks with a focus on cardiac symptoms, such as chest tightness and fear of having a heart attack.
  • Mitral Valve Prolapse: A condition where the mitral valve does not close properly, potentially causing chest discomfort, palpitations, and anxiety symptoms.
  • Costochondritis: Inflammation of the cartilage that connects the ribs to the breastbone, which can cause chest pain and discomfort, although this would typically be more localized and painful.