Differential Diagnosis for 61-year-old Female with Chest Pain and Breathlessness

Single Most Likely Diagnosis

• Acute Myocardial Infarction (MI): The patient presents with acute onset chest pain and breathlessness, which are classic symptoms of a heart attack. The elevated blood pressure (200/110 mmHg) and high random blood glucose (over 400) further increase the risk of MI. The fact that she is not responding to sarbotrate (likely a vasodilator or nitrates, commonly used for angina) suggests a more severe cardiac event.

Other Likely Diagnoses

• Hypertensive Emergency: Given the significantly elevated blood pressure, this could be contributing to or causing the chest pain and breathlessness, possibly leading to hypertensive heart disease or aortic dissection.
• Diabetic Ketoacidosis (DKA) or Hyperosmolar Hyperglycemic State (HHS): With a random blood glucose over 400 and the patient being on "sugar medicine" (zoryl M2, likely a metformin combination), DKA or HHS should be considered, especially if there are symptoms like polyuria, polydipsia, or altered mental status.
• Pulmonary Embolism (PE): Although less likely given the information, PE can cause acute onset chest pain and breathlessness. The lack of response to initial treatment could suggest a need to consider other diagnoses like PE.

Do Not Miss Diagnoses

• Aortic Dissection: This is a life-threatening condition that can present with sudden onset chest pain and is associated with hypertension. It's crucial to consider this diagnosis due to its high mortality rate if missed.
• Pulmonary Edema: Given the high blood pressure and potential for heart failure, pulmonary edema could be a cause of the symptoms, especially if there's evidence of fluid overload.
• Cardiac Tamponade: Although less common, cardiac tamponade can cause chest pain and breathlessness and is a medical emergency.

Rare Diagnoses

• Thyroid Storm: This condition can cause chest pain, breathlessness, and significant hypertension, among other symptoms. It's rare but should be considered in the differential diagnosis of a patient with these symptoms, especially if there's a history of thyroid disease.
• Pheochromocytoma: A rare tumor of the adrenal gland that can cause episodes of hypertension, chest pain, and breathlessness. It's unlikely but should be considered in cases of resistant hypertension.

Each of these diagnoses requires specific management and treatment. The patient's lack of response to initial treatment with sarbotrate suggests the need for immediate further evaluation and possibly more aggressive management in a monitored setting.