Antithrombotic Therapies: Balancing Clot Prevention and Bleeding Risk

Thrombosis is the pathologic clotting of blood in vessels, causing strokes and heart attacks. Antithrombotic therapy prevents and treats these dangerous clots.

1. Antithrombotic Therapies:
Balancing Clot Prevention
and Bleeding Risk
Thrombosis is the pathologic clotting of blood in vessels, causing strokes
and heart attacks. Antithrombotic therapy prevents and treats these
dangerous clots.
The challenge is creating treatments that don't increase bleeding risk, as
normal clotting (hemostasis) is essential for healing.

2. Types of Antithrombotic Medications
Anticoagulants
Slow clotting by preventing fibrin,
platelets, and blood cells from forming
clots. Examples: heparin, apixaban,
rivaroxaban.
Antiplatelets
Prevent arterial clotting by stopping
platelets from merging. Examples:
aspirin, ticagrelor, clopidogrel.
Thrombolytics
Break up existing clots by activating
proteins that dissolve fibrin. Used for
life-threatening situations. Examples:
alteplase, tenecteplase.

3. How Blood Thinners Work
1
Prevention
Anticoagulants and antiplatelets prevent new clots from
forming. They can be taken daily.
2
Maintenance
Blood thinners help prevent existing clots from growing
larger. They don't dissolve clots.
3
Dissolution
Thrombolytics break up existing clots. Reserved for life-
threatening situations like stroke or heart attack.

4. Treatment Applications
Ischemic Stroke
Thrombolytics dissolve clots blocking blood flow to the
brain. Time-sensitive treatment requires quick
administration.
Heart Attack
Thrombolytics restore blood flow to heart muscle.
Anticoagulants prevent new clots after treatment.
Deep Vein Thrombosis
Blood thinners prevent clots in leg veins from growing or
traveling to lungs. Long-term therapy may be needed.
Arterial Thrombosis
Antiplatelets prevent clots in arteries. Often prescribed
after stent placement or for those with arterial disease.

5. Challenges and
Innovations
1
Major Challenge
Preventing harmful clots while preserving normal
hemostasis. Blood thinning increases bleeding risk.
2
Promising Targets
Factor XI and XIa inhibitors may reduce thrombosis without
affecting normal clotting.
3
Reversal Agents
Protamine reverses heparins. Andexanet alfa reverses
apixaban and rivaroxaban. Idarucizumab reverses
dabigatran within minutes.

6. Prevention and Future Directions
1
Behavioral
Modifications
Maintain active lifestyle. Avoid
smoking. Manage conditions like
heart failure and COPD.
2
Current Limitations
Bleeding risk continues to
hamper appropriate use of
antithrombotic therapy.
3
Future Hope
Development of Factor XI/XIa
targeting anticoagulants may
provide safer options with
adequate protection.