What is the common cause of infective carditis?

A. A 79-year-old lifetime smoker who is complaining of shortness of breath and pain on deep inspiration: Chronic obstructive pulmonary disease (COPD) is most commonly seen in individuals with a significant smoking history. Progressive shortness of breath is a hallmark symptom of COPD, resulting from chronic airway inflammation and airflow limitation. While pain on deep inspiration is not a classic COPD symptom, it could indicate pleuritic involvement or hyperinflation-related chest discomfort.

B. An 88-year-old female who experiences acute shortness of breath and airway constriction when exposed to tobacco smoke: Acute shortness of breath and airway constriction in response to tobacco smoke suggests an asthma-like reaction rather than COPD. COPD symptoms tend to be persistent and progressive rather than episodic.

C. An 81-year-old smoker who has increased exercise intolerance, a fever, and increased white blood cells: Fever and increased white blood cells indicate an acute infection rather than chronic lung disease. While COPD exacerbations can cause worsening symptoms, an isolated fever and elevated white blood cells suggest pneumonia or another infectious process rather than COPD alone.

D. An 81-year-old male who has a productive cough and recurrent respiratory infections: A productive cough and recurrent respiratory infections are common in chronic bronchitis, a component of COPD. However, this presentation alone is not specific to COPD, as other conditions, such as bronchiectasis, can also cause these symptoms.

A. Increase peripheral resistance: An increase in peripheral resistance contributes to hypertension by raising the pressure in the arteries. This condition often results from vasoconstriction or structural changes in the blood vessels, leading to higher overall blood pressure.

B. Decrease in cardiac output: A decrease in cardiac output typically does not cause hypertension. In fact, low cardiac output may lead to hypotension (low blood pressure) since there is less blood being pumped into the circulatory system. This option is the exception when discussing physiological causes of hypertension.

C. Both increased cardiac output and peripheral resistance: Both increased cardiac output and peripheral resistance can lead to hypertension. An increase in either factor can elevate blood pressure, and their combined effect can significantly contribute to the development of hypertension.

D. Increased cardiac output: Increased cardiac output raises blood pressure by delivering more blood to the arteries with each heartbeat. This can occur due to various factors such as increased fluid volume, increased heart rate, or heightened contractility of the heart.