All of the following are normally involved in the pathogenesis of heart failure EXCEPT:

Correct Answer: C

Rationale: The correct answer is C: A decrease in preload. Preload refers to the volume of blood in the ventricles at the end of diastole, which affects the stretch of the myocardial fibers before contraction. In heart failure, preload is typically increased due to volume overload, not decreased. A cardiac lesion impairing cardiac output (A) is a common cause of heart failure. An increase in peripheral vascular resistance (B) can contribute to the pathogenesis by increasing afterload. An increase in sodium and water retention (D) is associated with volume overload and exacerbates heart failure symptoms. In summary, a decrease in preload is not normally involved in the pathogenesis of heart failure, making it the correct choice.

Correct Answer: B

Rationale: Rationale: Hydralazine is known to cause tachycardia as a side effect due to its vasodilatory properties. Lupus erythematosus can also be induced by hydralazine through its autoimmune effects. Seizures, extrapyramidal disturbances, acute hepatitis, and aplastic anemia are not typically associated with hydralazine use. Thus, option B is the correct choice.

Correct Answer: D

Rationale: The correct answer is D because oxytocin is indicated for all the mentioned conditions. A: Oxytocin helps induce labor and augment dysfunctional labor for early vaginal delivery. B: It can be used for incomplete abortion to help expel the remaining products of conception. C: Oxytocin is also used to control postpartum uterine hemorrhage by promoting uterine contractions. Therefore, all the options are valid indications for oxytocin use.

Correct Answer: D

Rationale: Rationale: The major synthetic estrogens are Dienestrol, Diethylstilbestrol, and Benzestrol, but not Estradiol. Estradiol is a natural estrogen produced by the ovaries. Therefore, D is the correct answer. Dienestrol, Diethylstilbestrol, and Benzestrol are synthetic estrogens used in hormone replacement therapy.

Correct Answer: A

Rationale: The correct answer is A. Metamizole use is associated with serious side effects such as agranulocytosis and aplastic anemia. Agranulocytosis is a severe decrease in white blood cells, leading to increased risk of infections. Aplastic anemia is a condition where the bone marrow does not produce enough blood cells. Choices B and C are incorrect as they are not known side effects of metamizole. Salicylism is associated with aspirin toxicity, while iatrogenic Cushing's syndrome is typically caused by prolonged use of glucocorticoids, not metamizole. Therefore, the correct choice is A as it accurately reflects the serious side effects of metamizole.