Cardiac Effects in Poisoning: Matching Agents

This question requires evaluating the accuracy of four pairs linking specific agents to their cardiac effects during overdose or poisoning.

Agent-Effect Pair Analysis

• 1. Prolonged PR interval - Lithium: This is a correctly matched pair. Lithium toxicity can manifest with various cardiac conduction abnormalities, including a prolonged PR interval on an electrocardiogram (ECG).
• 2. Prolonged QTc interval - Amiodarone: This is also a correctly matched pair. Amiodarone, an antiarrhythmic medication, is known to prolong the QTc interval, increasing the risk of potentially fatal arrhythmias like Torsades de Pointes.
• 3. Wide QRS complex - Kerosene ingestion: This pair is incorrectly matched. While kerosene ingestion can cause serious systemic effects and cardiac issues like metabolic acidosis or arrhythmias, a wide QRS complex is not its most characteristic or direct cardiovascular finding.
• 4. Tachycardia - Organophosphates: This pair is incorrectly matched. Organophosphate poisoning typically leads to cholinergic crisis, characterized by significant bradycardia due to increased vagal tone. Tachycardia is not the primary cardiac effect.

Conclusion

Based on the analysis, only pairs 1 and 2 are correctly matched. Therefore, there are exactly two correct pairs.