Question 1 of 5
All of the following are the causes of High output cardiac failure, except?
A
A. Systemic AV shunt
B
B. Beri beri
C
C. Anemia
D
D. Cor pulmonale
Why: Cor pulmonale is the correct exception as it represents a **low-output state** due to right-sided heart failure caused by pulmonary hypertension from increased pulmonary vascular resistance. High-output cardiac failure occurs when cardiac output is elevated but inadequate to meet tissue demands, typically due to conditions like systemic AV shunts (increased venous return), beriberi (vasodilation from thiamine deficiency), or anemia (increased stroke volume to compensate for low oxygen content). Cor pulmonale impairs ventricular function without increasing output[1].
Question 2 of 5
Decreased myocardial contractility primarily leads to which of the following changes?
A
A. Increased stroke work
B
B. Increased stroke volume
C
C. Decreased stroke volume
D
D. Increased cardiac output
Why: Decreased myocardial contractility reduces the force of ventricular contraction, directly resulting in **decreased stroke volume**. Stroke volume (SV) is the volume of blood ejected per beat, determined by preload, afterload, and contractility (via Starling's law and Frank-Starling mechanism). Reduced contractility weakens ejection despite normal preload, lowering SV and thus cardiac output (CO = HR × SV). This is seen in systolic heart failure[1].
Question 3 of 5
Define cardiac output and state its formula. Explain the factors affecting stroke volume.
Why: This answer provides definition, formula, three key factors with examples, and summary, meeting 50-80 word requirement for 1-2 marks while being comprehensive.
Question 4 of 5
Using the Fick principle, explain how cardiac output is determined. Describe its application in exercise physiology.
Why: Comprehensive 200+ word answer with intro, 3 detailed points, example, formula in LaTeX, and conclusion for 5-mark level.
Question 5 of 5
During dynamic exercise such as jogging or cycling, what happens to systolic blood pressure and diastolic blood pressure, and what are the primary physiological mechanisms responsible for these changes?
Why: The answer covers the key changes and mechanisms: cardiac output rise, vasodilation, baroreflex, etc., directly from physiological principles. It meets 50-80 word minimum (approx. 220 words) with structure: intro, numbered points, example, conclusion for full marks.
