Introduction & Key Takeaways

Saddle thrombus (feline aortic thromboembolism – FATE) is a sudden, life-threatening blockage of blood flow to a cat’s back legs, typically originating from a clot in the heart. 🫀⚠️

• 🐾 Sudden paralysis or weakness in one or both rear legs—painful and emergency situation.
• ❄️ Cold limbs, absence of femoral pulses, pale/blue paw pads, and vocalization are classic signs.
• 🫁 Often associated with heart disease (especially hypertrophic cardiomyopathy), hyperthyroidism, or tumors.
• 🔬 Diagnosis through physical exam and imaging (Doppler ultrasound, ECG).
• 💉 Treatment includes hospitalization, pain control, anticoagulants, oxygen, supportive care, and possibly surgical or catheter-based clot removal.
• 📉 Prognosis is guarded—30–40 % survive to discharge; recurrence is common.
• 🛡️ Long-term prevention involves anticoagulants like clopidogrel and managing underlying heart or thyroid disease.

1. What Is Saddle Thrombus?

A saddle thrombus is a blood clot lodged where the aorta splits into the iliac arteries supplying the hind legs—resulting in acute ischemia and paralysis :contentReference[oaicite:3]{index=3}.

Also known as feline aortic thromboembolism (FATE), the term "saddle" stems from the way the clot straddles major vessels :contentReference[oaicite:4]{index=4}.

2. Causes & Risk Factors

• ❤️ Most often seen in cats with heart disease—esp. hypertrophic cardiomyopathy; ~70% of FATE cases linked to cardiac pathology :contentReference[oaicite:5]{index=5}.
• 🦋 Other risks include hyperthyroidism (~9%), neoplasia (~5%), and systemic inflammation.
• ♂ Male cats are more commonly affected due to higher rates of heart disease :contentReference[oaicite:6]{index=6}.

3. Clinical Signs

The “5‑P” signs to look for:

• Paresis/Paralysis: hind limbs affected, rarely front limbs.
• Pain: vocalization, rapid breathing, hiding :contentReference[oaicite:7]{index=7}.
• Pulseless: lacking femoral pulses in affected limb(s).
• Pallor/Pale or bluish paw pads: especially with cold toes.
• Poikilothermia: limb temperature reduced relative to body.

Additional signs: shortness of breath, heart murmur/arrhythmia, vomiting :contentReference[oaicite:8]{index=8}.

4. Diagnosis & Emergency Evaluation

• Physical exam: assess pulses, limb temperature, pain response.
• Doppler/Infrared imaging: confirms absent blood flow :contentReference[oaicite:9]{index=9}.
• Thoracic imaging (echocardiogram): identifies heart disease.
• Blood work & ECG: evaluate underlying conditions (e.g., thyroid, renal function).

5. Treatment & Hospital Care

Immediate Goals

• Pain control with opioids (e.g., fentanyl, levomethadone) :contentReference[oaicite:10]{index=10}.
• Oxygen supplementation to support compromised perfusion :contentReference[oaicite:11]{index=11}.
• IV fluids to stabilize and reduce reperfusion injury risk :contentReference[oaicite:12]{index=12}.
• Thromboprophylaxis with clopidogrel (superior to aspirin) and possibly rivaroxaban :contentReference[oaicite:13]{index=13}.

Surgical/Thrombolytic Options

• Thrombolytics (e.g., rtPA) used experimentally; recent promising case recoveries :contentReference[oaicite:14]{index=14}.
• Surgical or catheter-based clot removal is possible but risky—reperfusion injury can be fatal :contentReference[oaicite:15]{index=15}.

Supportive & Rehab Care

• Physiotherapy such as gentle limb movement, massage :contentReference[oaicite:16]{index=16}.
• Aid for toileting, food, grooming if paralyzed.
• Address underlying disease (heart, thyroid, cancer) to reduce recurrence :contentReference[oaicite:17]{index=17}.

6. Prognosis & Statistics

• 🐾 Survival to discharge ranges from 30–40 % :contentReference[oaicite:18]{index=18}.
• Median survival historically 3–6 months; newer protocols may reach over 1 year :contentReference[oaicite:19]{index=19}.
• Re‑thrombosis is common, ~50% recurrence even with anticoagulants :contentReference[oaicite:20]{index=20}.

Many cats are euthanized on presentation due to pain and poor prognosis :contentReference[oaicite:21]{index=21}.

7. At‑Home Care & Monitoring

• Administer medications (clopidogrel, pain meds) as directed.
• Provide thermoregulated bedding and encourage gentle limb use.
• Assist toileting and feeding as needed.
• Use gentle physical therapy as pain allows.
• Schedule regular follow-ups: bloodwork, ECG/echo, and limb assessments.

Monitor closely for signs of recurrence: acute pain, limb changes, or labored breathing.

8. Prevention & Owner Recommendations

• Regular cardiac screenings for at-risk cats—especially breeds like Ragdoll, Maine Coon, and males :contentReference[oaicite:22]{index=22}.
• Early treatment of heart disease (ACE inhibitors, beta-blockers, pimobendan) and thyroid disease.
• Maintain antithrombotic therapy if underlying risk remains.
• Use the Ask A Vet app for remote monitoring, medication reminders, and emergency support.

9. FAQs

Can a cat walk again after a saddle thrombus?

Yes—some recover with intensive care and physical therapy, but others may have permanent weakness or paralysis.

Is euthanasia the only option?

No—many veterinarians offer aggressive treatment for viable cases, though prognosis remains guarded.

Should I give aspirin or clot-busters at home?

No—thrombolytics can be dangerous. Always follow veterinary guidance and avoid home-clot medications.

How long will treatment cost?

Initial hospitalization can be pricey ($2,000–$10,000+), with ongoing anticoagulant cost and follow-ups.

Conclusion

Saddle thrombus in cats is a devastating and painful emergency. Quick detection, veterinary intervention, and comprehensive supportive care can help—but long-term management is essential.

For guidance on recognizing symptoms, post-crisis care, antithrombotic therapy, or heart disease support, contact Ask A Vet or download the app for 24/7 veterinary backup 🐾📲.