What is the amount of tension the ventricle must develop during contraction to eject blood from the left ventricle into the aorta?

Correct Answer: A

Rationale: The correct answer is A: Afterload. Afterload refers to the amount of tension the ventricle must develop during contraction to eject blood into the aorta. It is the resistance the heart must overcome to eject blood. Preload (B) is the stretch on the heart muscle before contraction. Automaticity (C) refers to the heart's ability to generate electrical impulses. Ejection fraction (D) is the percentage of blood pumped out of the ventricle with each heartbeat.

Correct Answer: A

Rationale: Step 1: Heart failure is characterized by the heart's inability to effectively pump blood, leading to fluid buildup and swelling. Step 2: Cardiomyopathy is a disease of the heart muscle, which may contribute to heart failure but is not the direct cause of fluid buildup. Step 3: Angina is chest pain due to reduced blood flow to the heart, not directly related to fluid buildup. Step 4: Myocarditis is inflammation of the heart muscle, which can lead to heart failure but is not the primary cause of fluid accumulation. Summary: Heart failure is the correct answer as it directly relates to the inability of the heart to pump blood effectively, leading to fluid accumulation. Cardiomyopathy, angina, and myocarditis are related to heart health but do not directly cause fluid buildup in the body.

Correct Answer: A

Rationale: The correct answer is A: Cardiac output. Cardiac output is the total amount of blood pumped by the heart in a minute. It is calculated by multiplying the heart rate (beats per minute) by the stroke volume (amount of blood pumped per beat). This measurement gives an indication of how effectively the heart is functioning in delivering oxygenated blood to the body. B: Stroke volume is the amount of blood pumped by the heart in each beat, not the total amount in a minute. C: End-diastolic volume is the amount of blood in the ventricles before contraction, not the total amount pumped in a minute. D: Ejection fraction is the percentage of blood pumped out of the ventricles with each contraction, not the total amount in a minute.

Correct Answer: A

Rationale: The correct answer is A: Cardiac arrest. Cardiac arrest is a life-threatening emergency where the heart stops beating suddenly. This leads to the cessation of blood flow to vital organs, causing loss of consciousness and death if not treated immediately with CPR and defibrillation. Myocardial infarction (B) is a heart attack where blood flow to the heart muscle is blocked, leading to tissue damage. Heart failure (C) is a chronic condition where the heart is unable to pump blood effectively. Atrial fibrillation (D) is an irregular heartbeat that can increase the risk of stroke but is not the same as cardiac arrest.

Correct Answer: A

Rationale: Step-by-step rationale: 1. Hypertrophic cardiomyopathy (A) is the correct answer. 2. In this condition, the heart muscle thickens, leading to decreased blood pumping ability. 3. This thickening can obstruct blood flow and increase the risk of abnormal heart rhythms. 4. Dilated cardiomyopathy (B) involves the heart enlarging and weakening, not thickening. 5. Restrictive cardiomyopathy (C) involves stiffening of the heart muscle, not thickening. 6. Ischemic cardiomyopathy (D) results from reduced blood flow to the heart, not thickening.