What main etiology would we be concerned about with pleuritic cp and tachycardia?

Pulmonary Embolism (PE)

Explanation:

A pulmonary embolism is a condition where one of the main arteries in the lungs is blocked by a substance that has moved from elsewhere in the body through the bloodstream.

This would be a cause for concern for patients with pleuritic CP because patients with PE's usually present with shortness of breath, chest pain particularly upon breathing in and coughing up blood and due to its position in the lungs, it can also be life-threatening. This symptoms are also very similar and can result in a PE being missed completely on examination causing it to be a high risk

weathering is the answer.