Changes

==Introduction==

==Introduction==

Cats that present with '''aortic thromboembolism''' almost invariably have significant '''underlying cardiac disease''' and often show overt signs of '''congestive heart failure'''. Treatment of the condition can be very challenging both in the prevention of reperfusion injury and management of existing heart problems.  

Cats that present with '''aortic thromboembolism''' almost invariably have significant '''underlying cardiac disease''' and often show overt signs of '''congestive [[:Category:Heart Failure|heart failure]]'''. Treatment of the condition can be very challenging both in the prevention of reperfusion injury and management of existing heart problems.  

==Pathogenesis==

==Pathogenesis==

'''2)''' A series of subsequent '''vasoconstrictive events''' that decrease collateral circulation.  

'''2)''' A series of subsequent '''vasoconstrictive events''' that decrease collateral circulation.  

'''3)''' '''Reperfusion injury''' following the breakdown of the clot and return of collateral circulation.   

'''3) Reperfusion injury''' following the breakdown of the clot and return of collateral circulation.   

The consequence of this is '''ischaemic neuromyopathy'''. The '''muscle''' is quite '''sensitive''' to ischaemic damage - with the clot causing a '''rigor mortis''' effect in the tissue. The '''[[Peripheral Nervous System - Response to Injury|peripheral nerves]]''' are fairly '''resistant''' to structural damage but they undergo rapid functional change. This functional failure can be reversed it blood flow is restored before structural nerve damage occurs (several hours later). The amount of structural nerve damage determines the level of permanent nerve damage.   

The consequence of this is '''ischaemic neuromyopathy'''. The '''muscle''' is quite '''sensitive''' to ischaemic damage - with the clot causing a '''rigor mortis''' effect in the tissue. The '''peripheral nerves''' are fairly '''resistant''' to structural damage but they undergo rapid functional change. This functional failure can be reversed if blood flow is restored before [[Peripheral Nervous System - Response to Injury|structural nerve damage]] occurs (several hours later). The amount of structural nerve damage determines the level of permanent nerve damage.   

==Signalment==

==Signalment==

==Clinical Signs==

==Clinical Signs==

The most common presenting signs are '''acute rear limb paralysis, depression, pain and dyspnoea'''. The paralysis may be unilateral or bilateral. On clinical exam there is an '''absence of femoral pulses''' in the affected limbs and the [[Canine Hindlimb - Anatomy & Physiology|cranial tibial and gastrocnemius muscles]] feel firm on palpation. The '''footpads are cold''' and '''discoloured''' and there is '''no response to noxious stimuli''' or '''movement''' in the lower limb. Additional findings include a lack of tone in the anal sphincter, bladder distention and abdominal pain. Pain and underlying cardiac disease can cause '''tachycardia and tachypnoea'''. Additional signs of cardiac disease may be detected on cardiac auscultation such as a '''murmur, arrhythmia''' or gallop rhythm.

The most common presenting signs are '''acute rear limb paralysis, depression, pain and [[Dyspnoea - Cat|dyspnoea]]'''. The paralysis may be unilateral or bilateral. On clinical exam there is an '''absence of femoral pulses''' in the affected limbs and the [[Canine Hindlimb - Anatomy & Physiology|cranial tibial and gastrocnemius muscles]] feel firm on palpation. The '''footpads are cold''' and '''discoloured''' and there is '''no response to noxious stimuli''' or '''movement''' in the lower limb. Additional findings include a lack of tone in the anal sphincter, bladder distention and abdominal pain. Pain and underlying cardiac disease can cause '''tachycardia and tachypnoea'''. Additional signs of cardiac disease may be detected on cardiac auscultation such as a '''[[Heart Murmur|murmur]], [[Arrhythimas|arrhythmia]]''' or gallop rhythm.

Reperfusion injury, which occurs several hours after clot formation may cause '''depression, [[Arrhythmias Overview|arrhythmias]] and cardiac conduction abnormalities'''. This can be fatal. Swelling and [[Oedema|oedema]] of the limbs is seen once reperfusion occurs.  

Reperfusion injury, which occurs several hours after clot formation may cause '''depression, [[Arrhythmias Overview|arrhythmias]] and cardiac conduction abnormalities'''. This can be fatal. Swelling and [[Oedema|oedema]] of the limbs is seen once reperfusion occurs.