Question

A middle-aged woman is admitted to the coronary care unit with a diagnosis of left ventricular failure resulting from a myocardial infarction. Her history indicated that she was aroused in the middle of the night by severe chest pain. Her skin is pale and cold, and moist sounds are heard over the lower regions of both lungs. Explain how failure of the left ventricle can cause these signs and symptoms.

Answer 1

Left ventricular failure caused by a myocardial infarction can lead to pulmonary edema, resulting in symptoms such as dyspnea, angina pectoris, and cold, pale skin due to inadequate blood flow and oxygenation.

Step-by-step explanation:

When a patient is diagnosed with left ventricular failure as a result of a myocardial infarction (MI), the symptoms described can be directly attributed to the heart's reduced ability to pump blood effectively. Because the left ventricle is responsible for pumping oxygenated blood to the entire body, its failure leads to a buildup of fluid in the lungs, known as pulmonary edema. This is the cause of the moist sounds heard over the lower regions of both lungs, also referred to as hypoxemia. The pallor of the skin and its coldness is due to poor circulation, and the severe chest pain that awakened the woman is consistent with angina pectoris, a typical manifestation of an MI in its acute form.

Furthermore, left ventricular failure can lead to backup of blood into the lungs, causing shortness of breath or dyspnea, and other signs of poor oxygenation such as fainting (syncope), anxiety, sweating (diaphoresis), and irregular heartbeat (palpitations). The failure of the left ventricle means it can't maintain adequate pressure to propel blood through the arterial system, which has cascading effects on the entire body, precipitating the array of symptoms described.

Answer 2

1. The oxygen deprived cardiac muscles caused chest pain.

2. Unavailability of oxygen and blood supply to skin cells made them pale and cold.

3. Accumulation of blood in pulmonary circuit caused moist sounds.

Step-by-step explanation:

The left ventricle receives oxygenated blood from the left atrium. Oxygenated blood from the lungs is carried to the left atrium by pulmonary veins. The left ventricle pumps the oxygenated blood to all body parts through the aorta. Failure of the left ventricle deprived the skin cells of oxygenated blood. Oxygen deficiency stopped energy production by cellular respiration. The result was pale and cold skin.

Failure of the left ventricle led to the accumulation of blood in the pulmonary circuit since the blood was not delivered to body tissues. The build-up of blood and resultant higher blood pressure caused moist sounds in the lower lungs.

The blockage of the coronary artery by a blood clot and death of a part of the heart due to lack of oxygen leads to a heart attack. The dead heart tissue is known as infarct and the resultant heart attack is myocardial infarction. Chest pain is caused due to the dead heart tissue or infarct.