Acute Coronary Syndrome (ACS): This is often the first consideration for acute chest pain, especially in patients with risk factors such as hypertension, diabetes, high cholesterol, or a family history of heart disease. The pain is typically described as a pressure or heaviness in the chest that may radiate to the arm, neck, or jaw.

Pulmonary Embolism (PE): Sudden onset of chest pain, especially if it worsens with deep breathing (pleuritic chest pain), should raise suspicion for a pulmonary embolism. Risk factors include recent surgery, immobilization, cancer, or a history of deep vein thrombosis.
Pneumonia: Chest pain associated with fever, cough, and shortness of breath could indicate pneumonia. The pain is often sharp and worsens with deep breathing or coughing.
Gastroesophageal Reflux Disease (GERD): GERD can cause chest pain that mimics cardiac issues, often described as a burning sensation that may radiate to the neck or arms, typically after eating or at night.
Musculoskeletal Pain: Strain or inflammation of the muscles or bones in the chest wall can cause sharp pains, especially with movement or palpation.

Aortic Dissection: Although less common, aortic dissection is a medical emergency that presents with severe, tearing chest pain that radiates to the back. It is crucial to consider this diagnosis, especially in patients with hypertension or a history of aortic aneurysm.
Pneumothorax: Sudden onset of sharp chest pain and shortness of breath could indicate a pneumothorax, especially in tall, thin males or those with underlying lung disease.
Pericarditis: Inflammation of the pericardium can cause sharp, stabbing chest pain that improves with sitting up and leaning forward. It's often accompanied by a pericardial friction rub.

Esophageal Rupture: Severe, constant chest pain that worsens with swallowing, along with vomiting or fever, could indicate an esophageal rupture, which is a surgical emergency.
Spontaneous Hematoma of the Chest Wall: Rarely, a spontaneous hematoma in the chest wall can cause acute chest pain, often without a clear history of trauma.
Chest Wall Tumors: Although rare, tumors of the chest wall, such as osteosarcomas or chondrosarcomas, can cause localized pain and should be considered in the differential diagnosis, especially with a palpable mass.