# A client with atrial fibrillation and a mechanical mitral valve asks which oral anticoagulant is expected for long-term stroke and valve-thrombosis prevention. Which response is best?

> source: MyMerci (mymerci.kr)  
> url: https://mymerci.kr/pages/nclex_q.php?qn_id=522060&lang=en  
> language: en  
> subject: Adverse Effects/Contraindications/Interactions  
> category: PPT

## Question

A client with atrial fibrillation and a mechanical mitral valve asks which oral anticoagulant is expected for long-term stroke and valve-thrombosis prevention. Which response is best?

## Option

1. Aspirin alone because atrial fibrillation is intermittent
2. Warfarin with valve-specific INR monitoring **✔ Correct answer**
3. Apixaban without laboratory or valve review
4. Clopidogrel alone because it acts on platelets

**Correct answer: 2**

## Explanation

Vitamin K antagonist therapy is recommended for mechanical valves; direct oral anticoagulants are not used as substitutes in this setting.

## In-depth explanation

Quick answer
Expect warfarin with valve-specific INR monitoring.

Why this is correct
ACC/AHA guidance excludes mechanical valves from the usual preference for DOACs in atrial fibrillation. The valve type and thromboembolic risk determine the VKA target and monitoring plan.

Easy analogy or mental picture
A mechanical valve requires the anticoagulant lane with established valve evidence, not a convenient shortcut.

Memory hook
Mechanical valve means VKA, not DOAC substitution.

NCLEX decision rule
Identify the valve before applying the general atrial-fibrillation anticoagulant rule.

Why the other choices are wrong
Aspirin or clopidogrel alone does not replace anticoagulation, and apixaban is not the expected mechanical-valve therapy.References
1ACC/AHA 2023 Atrial Fibrillation GuidelineDOAC preference exceptions for mechanical valves and moderate-to-severe mitral stenosis
2ACC/AHA 2020 Valvular Heart Disease GuidelineVKA therapy for mechanical valves, pregnancy counseling, and monitored anticoagulation planning

## Clinical scenario

Valve anticoagulant verification
Confirm valve position and type, rhythm, prior thromboembolism, INR goal, interacting drugs, adherence, bleeding, and monitoring access.

## Related questions

- [A nurse is reviewing the morning lab results for an adult client receiving warfarin for at…](https://mymerci.kr/pages/nclex_q.php?qn_id=360515&lang=en)
- [A client is admitted to the emergency department after ingesting an unknown amount of acet…](https://mymerci.kr/pages/nclex_q.php?qn_id=362720&lang=en)
- [A client with chronic heart failure is prescribed metoprolol 25 mg orally twice daily. Bef…](https://mymerci.kr/pages/nclex_q.php?qn_id=362756&lang=en)
- [A 28-year-old client with type 1 diabetes receives regular insulin 6 units and NPH insulin…](https://mymerci.kr/pages/nclex_q.php?qn_id=362792&lang=en)
- [A client receives IV vancomycin 1 g every 12 hours for MRSA bacteremia. Before the next do…](https://mymerci.kr/pages/nclex_q.php?qn_id=362833&lang=en)
- [A client with bipolar disorder has been taking lithium carbonate 600 mg orally three times…](https://mymerci.kr/pages/nclex_q.php?qn_id=362894&lang=en)
- [An 80-year-old male with heart failure is prescribed digoxin 0.125 mg daily. During mornin…](https://mymerci.kr/pages/nclex_q.php?qn_id=372686&lang=en)
- [A 38-year-old female with rheumatoid arthritis is being discharged with a new prescription…](https://mymerci.kr/pages/nclex_q.php?qn_id=372687&lang=en)

## Read in another language

- [en](https://mymerci.kr/pages/nclex_q.php?qn_id=522060&lang=en)
- [ko](https://mymerci.kr/pages/nclex_q.php?qn_id=522060&lang=ko)
- [ja](https://mymerci.kr/pages/nclex_q.php?qn_id=522060&lang=ja)
- [zh-TW](https://mymerci.kr/pages/nclex_q.php?qn_id=522060&lang=zh-tw)
- [vi](https://mymerci.kr/pages/nclex_q.php?qn_id=522060&lang=vi)

---

More free questions: [NCLEX-RN Practice](https://mymerci.kr/pages/nclex_bank.php?lang=en)

_For study reference only. Always follow current clinical guidelines and your institution’s protocols._