Renal infarction

Renal infarction occurs when blood flow to a portion of the kidney is suddenly blocked, typically by a blood clot or embolus, causing death of the kidney tissue deprived of oxygen and nutrients. This serious vascular condition results in permanent damage to the affected area of the kidney, with the extent of damage determined by how much of the kidney's blood supply is compromised. Renal infarction can affect one or both kidneys and may involve small or large portions of kidney tissue. In cats, this condition is most commonly associated with underlying cardiac disease that predisposes to blood clot formation, making it a particularly concerning finding that often indicates significant heart problems requiring immediate attention.

The condition develops when a blood clot, usually forming in the heart chambers due to abnormal blood flow patterns associated with cardiomyopathy, breaks free and travels through the arterial system until it lodges in a renal artery or one of its branches. Less commonly, clots may form locally in the renal vessels due to vessel wall abnormalities, clotting disorders, or severe dehydration. When blood flow is blocked, the kidney tissue downstream from the obstruction rapidly becomes ischemic and begins to die. The body cannot restore the damaged tissue, so the affected area is replaced by scar tissue over time, resulting in permanent loss of that portion of the kidney's functional capacity.

The impact of renal infarction on a cat's health depends on several factors including the amount of kidney tissue affected, whether one or both kidneys are involved, the underlying cause of the clot formation, and the cat's pre-existing kidney function. Small infarcts may cause minimal clinical effect, particularly if overall kidney reserve is adequate. Larger infarcts or bilateral involvement can cause acute kidney injury with sudden decline in kidney function. The acute event often causes significant pain and systemic illness. Beyond the immediate kidney effects, the presence of renal infarction typically indicates underlying cardiac disease that poses ongoing risks including potentially life-threatening arterial thromboembolism to other organs such as the hind limbs.

Treatment for renal infarction focuses on managing the acute event, supporting kidney function, and addressing the underlying cause to prevent recurrence. Pain management and supportive care help cats through the acute crisis. Anticoagulant therapy may be initiated to prevent additional clot formation. Cardiac disease evaluation and treatment are essential components of the management plan. With appropriate treatment of underlying heart disease and preventive anticoagulation, some cats can achieve good quality of life despite the kidney damage. However, the prognosis depends heavily on the nature and severity of the underlying cardiac condition, the extent of kidney damage, and whether additional thromboembolic events can be prevented.

The primary cause of renal infarction in cats is thromboembolism originating from the heart, with the vast majority of cases occurring in cats with underlying cardiomyopathy. Hypertrophic cardiomyopathy, the most common feline heart disease, creates conditions favorable for blood clot formation in the left atrium due to abnormal blood flow patterns and enlarged cardiac chambers. Other forms of cardiomyopathy including dilated, restrictive, and unclassified cardiomyopathies also predispose to thrombus formation. When these cardiac thrombi break free, they become emboli that travel through the arterial system. While the saddle thrombus affecting the distal aorta and hind limb arteries is the most recognized feline arterial thromboembolism presentation, emboli can also lodge in renal arteries, causing kidney infarction.

While cardiac disease is the predominant cause, other factors can lead to renal infarction. Clotting disorders, whether inherited or acquired, can predispose to inappropriate thrombus formation. Severe dehydration with resulting blood viscosity changes may contribute to clot development. Infectious or inflammatory conditions affecting the vascular system can damage vessel walls and trigger clotting. Neoplasia, particularly tumors that invade blood vessels or produce procoagulant substances, can cause thrombotic events. In rare cases, direct trauma to renal vessels or surgical complications may result in renal infarction. Some cases remain idiopathic with no identifiable underlying cause despite thorough investigation.

Environmental and lifestyle factors generally play a minor role in renal infarction compared to underlying disease states, but certain factors may contribute to overall risk. Chronic stress may exacerbate underlying cardiac conditions. Sedentary lifestyle and obesity can worsen cardiomyopathy and overall cardiovascular health. Dehydration from any cause increases blood viscosity and clotting tendency. Very high or very low environmental temperatures can stress the cardiovascular system. While these factors alone rarely cause renal infarction, they may contribute to disease progression or trigger acute events in cats with underlying predispositions.

Risk factors for renal infarction are closely tied to conditions that promote blood clot formation. Cats with diagnosed cardiomyopathy are at significantly elevated risk, with studies suggesting up to 25 percent of cats with hypertrophic cardiomyopathy will experience arterial thromboembolism during their lifetime. Left atrial enlargement on echocardiography is a particularly strong predictor of thromboembolic risk. Male cats appear to be affected more frequently than females, possibly related to higher cardiomyopathy prevalence. Middle-aged to older cats are more commonly affected as cardiac disease becomes more prevalent with age. Certain breeds with higher cardiomyopathy incidence, including Maine Coon, Ragdoll, and British Shorthair, may have elevated risk. Previous thromboembolic events significantly increase the likelihood of recurrence.

The mechanism of renal infarction involves complete or near-complete obstruction of blood flow through the renal artery or its branches. When an embolus lodges in a renal vessel, the downstream tissue is immediately deprived of oxygen and nutrients essential for cellular survival. Kidney tissue is highly metabolically active and cannot tolerate prolonged ischemia. Within minutes to hours, cells begin to die through necrosis. The extent of infarction depends on which vessel is occluded and whether collateral blood supply can compensate. Over the following days to weeks, the dead tissue is gradually replaced by fibrous scar tissue, resulting in permanent loss of functional kidney mass. If the infarction is large or affects both kidneys, acute kidney injury results from the sudden loss of filtration capacity.

Early warning signs of renal infarction are often difficult to identify because the event typically occurs suddenly with little to no prodromal period. However, cats with underlying cardiac disease may show subtle signs of heart problems before a thromboembolic event occurs, including mild exercise intolerance, increased respiratory rate, or occasional episodes of weakness. Some cats may have been previously diagnosed with heart disease, making owners aware of the thromboembolic risk. In cases where renal infarction is the first manifestation of cardiac disease, there may be no warning signs at all before the acute event occurs. The sudden onset of symptoms without prior illness history is characteristic of this condition.

Common symptoms of acute renal infarction reflect both the pain of the kidney event and the systemic effects of sudden loss of kidney function. Affected cats typically show sudden onset of vocalization, restlessness, or signs of severe pain. Vomiting is common and may be persistent. Anorexia develops quickly, with complete refusal of food. Lethargy and depression rapidly ensue as the cat feels increasingly unwell. Some cats may show signs specific to kidney pain including a hunched posture, reluctance to move, or sensitivity when the flank area is touched. If significant kidney function is lost, increased thirst and urination may develop as the remaining kidney tissue attempts to compensate.

Behavioral changes accompanying renal infarction often reflect pain and systemic illness. Cats may hide or seek unusual locations, becoming reclusive and avoiding interaction. Affected cats typically stop grooming and may have a disheveled appearance. Restlessness alternating with profound lethargy is common as cats struggle with discomfort. Appetite is usually severely affected, with cats showing no interest in food. Litter box avoidance may occur if movement is painful. Some cats become vocal, crying out particularly when moved or when the abdomen is touched. Changes in posture including reluctance to lie down or frequent position changes may indicate ongoing discomfort.

Physical signs of renal infarction include pain response on palpation of the affected kidney or flank region, though some cats may be too ill to show localized response. Dehydration may develop quickly due to vomiting and reduced fluid intake. Fever is sometimes present during the acute phase. Rapid breathing may indicate pain or concurrent cardiac issues. If the cat also has arterial thromboembolism affecting other organs, additional signs may be present such as cold, painful hind limbs with absent pulses in cases of saddle thrombus. Changes in heart rate or rhythm may be detected on examination if underlying cardiac disease is present. In severe cases, shock signs including pale gums, weak pulses, and altered consciousness may develop.

Symptom progression in renal infarction typically involves an acute crisis phase followed by gradual stabilization if the cat survives the initial event. The acute phase, lasting hours to days, is characterized by the most severe pain and systemic illness. Vomiting and pain typically peak during this period. If treatment is initiated and complications are managed, cats often show gradual improvement over several days. Pain diminishes as the acute inflammatory response subsides and scar tissue begins to form. Appetite may slowly return. However, if both kidneys are severely affected or underlying cardiac disease is advanced, progressive deterioration may occur despite treatment.

Emergency symptoms requiring immediate veterinary attention include sudden onset of severe pain, distress, or vocalization, particularly in a cat with known heart disease. Sudden collapse, inability to use hind legs, or cold painful limbs indicate possible saddle thrombus requiring emergency care. Persistent vomiting, complete food refusal, or severe lethargy warrant urgent evaluation. Difficulty breathing may indicate heart failure accompanying the thromboembolic event. Any sudden change in a cat with cardiac disease should be treated as an emergency given the risk of life-threatening complications. Renal infarction itself requires immediate veterinary attention for pain management, supportive care, and evaluation of underlying cause.

Initial examination for suspected renal infarction involves rapid assessment of the cat's overall status along with targeted evaluation for cardiovascular disease and kidney involvement. The veterinarian will assess vital signs including heart rate, rhythm, respiratory rate, and blood pressure. Careful cardiac auscultation listens for murmurs, arrhythmias, or abnormal heart sounds. Physical examination includes palpation of peripheral pulses to check for evidence of arterial obstruction elsewhere, assessment of extremity temperature and muscle tone, and gentle abdominal palpation to evaluate kidney pain and size. The examination aims to identify both the acute problem and any underlying conditions contributing to thrombus formation.

Diagnostic testing for renal infarction includes laboratory work and imaging studies to characterize kidney damage and evaluate cardiac status. Blood chemistry panel measures kidney function parameters including creatinine, blood urea nitrogen, and phosphorus, with elevations indicating acute kidney injury. Complete blood count may show stress leukogram or other changes. Coagulation testing helps evaluate clotting status. Cardiac biomarkers such as cardiac troponin may be elevated if heart muscle damage is present. Urinalysis may show blood, protein, or other abnormalities. Importantly, echocardiography is essential to evaluate for underlying cardiac disease and may reveal chamber enlargement, wall abnormalities, or even visible thrombus in the heart chambers.

Differential diagnosis considers other conditions that can cause acute kidney injury or similar clinical presentation. Pyelonephritis or other kidney infections may cause acute kidney pain and dysfunction but typically have different onset patterns and may show evidence of urinary tract infection. Acute toxin exposure can cause sudden kidney damage but usually has identifiable exposure history. Urinary obstruction causes acute kidney injury but has characteristic findings on imaging and physical examination. Kidney trauma must be considered if there is relevant history. The presence of cardiac disease and characteristic imaging findings help distinguish renal infarction from these other conditions.

Confirmation of renal infarction diagnosis relies primarily on imaging findings in the appropriate clinical context. Abdominal ultrasound may show characteristic wedge-shaped hypoechoic areas in the kidney corresponding to infarcted tissue, though early infarcts may be difficult to visualize. Doppler ultrasound can demonstrate absence of blood flow in affected areas. Contrast-enhanced CT provides detailed imaging of kidney perfusion and can clearly delineate infarcted regions, though this is not available at all veterinary facilities. Over time, chronic infarcts become visible as areas of scarring and cortical depression. The combination of acute clinical presentation, evidence of cardiac disease on echocardiography, and characteristic kidney imaging findings typically provides sufficient diagnostic certainty. Results from basic blood work and ultrasound are usually available within hours, guiding initial treatment while more comprehensive evaluation continues.

Immediate treatment for renal infarction focuses on pain management, supportive care, and stabilization of the acutely ill patient. Effective pain control is essential, with opioid medications commonly used to provide adequate analgesia. Intravenous fluid therapy helps maintain blood pressure, support kidney perfusion, and prevent dehydration. Anti-nausea medications address vomiting and improve comfort. If the cat is in shock or severely compromised, more aggressive stabilization including oxygen supplementation and treatment of cardiac complications may be needed. The immediate goal is to manage the acute crisis and prevent further deterioration while diagnostic workup proceeds.

Medical management of renal infarction extends beyond the acute phase to include treatment of underlying cardiac disease and prevention of additional thromboembolic events. Anticoagulant or antiplatelet therapy is typically initiated to reduce the risk of future clot formation. Clopidogrel is commonly used in cats as an antiplatelet agent, though some protocols include low-dose aspirin. In select cases, more aggressive anticoagulation with drugs like rivaroxaban may be considered. Cardiac medications are prescribed based on echocardiographic findings and may include beta-blockers, calcium channel blockers, or ACE inhibitors. If heart failure is present, diuretics and other heart failure medications are added. Long-term medication compliance is essential for preventing recurrence.

Surgical options for renal infarction are extremely limited in clinical practice. Unlike arterial thromboembolism affecting the limbs where thrombolytic therapy or surgical embolectomy has been attempted, intervention to restore renal blood flow is rarely feasible due to the small vessel size and difficulty accessing the renal vasculature. By the time diagnosis is made, irreversible tissue damage has usually already occurred. The focus of treatment is therefore on preventing additional infarcts rather than reversing existing damage. In rare cases where a single kidney is severely damaged while the other remains functional, nephrectomy might be considered if the affected kidney becomes a source of ongoing problems, but this is uncommon.

Supportive care helps cats recover from the acute event and manages any resulting chronic kidney disease. Nutritional support is important, with appetite stimulants used if needed and high-quality diet appropriate for any degree of kidney impairment. Fluid therapy may continue as subcutaneous fluids at home if dehydration is ongoing. If the infarction has caused significant loss of kidney function, standard chronic kidney disease management is implemented including dietary modification, phosphorus management, and monitoring for complications. Blood pressure monitoring and treatment of hypertension if present protects remaining kidney function and other organs.

Alternative and complementary approaches play a limited role in renal infarction management, as the primary treatment must address the underlying cardiac disease and prevent thromboembolism. Once the acute phase has passed, omega-3 fatty acid supplementation may provide some cardiovascular and anti-inflammatory benefits. Stress reduction through environmental management supports overall cardiovascular health. Acupuncture has been used by some practitioners for supportive care in cats with chronic conditions. However, these approaches should never replace appropriate cardiac medications and anticoagulant therapy, which are essential for preventing potentially fatal recurrent thromboembolic events.

Treatment decisions for cats with renal infarction involve consideration of the underlying cardiac disease severity, extent of kidney damage, and overall prognosis. Cats with early-stage cardiac disease and small renal infarcts may do well with appropriate management. Those with advanced heart failure or large bilateral infarcts causing acute kidney injury face more guarded prognoses. The risk of recurrent thromboembolism despite treatment must be discussed honestly with owners. Cost of ongoing cardiac medications, anticoagulants, and monitoring represents a significant commitment. Quality of life considerations are particularly important, as treatment aims to provide comfortable, functional life rather than cure. The veterinary team helps owners understand realistic expectations and make decisions aligned with their cat's best interests.

Recovery timeline for cats with renal infarction depends on the severity of the event, extent of kidney damage, and underlying cardiac disease status. The acute phase of illness typically lasts several days to a week, during which pain management and supportive care are intensive. Many cats show improvement in comfort and appetite within 48 to 72 hours of initiating treatment. Full stabilization after an acute infarction event may take one to three weeks. However, the kidney damage itself is permanent, with infarcted tissue eventually replaced by scar tissue over weeks to months. Recovery therefore refers to returning to stable chronic management rather than restoration of lost kidney function.

Post-treatment care involves establishing routines for cardiac medications and anticoagulants that will continue long-term or lifelong. Owners must administer medications consistently and learn to recognize signs of potential complications. Follow-up appointments monitor kidney function through blood work, assess cardiac status through periodic echocardiography, and evaluate medication effectiveness and tolerance. Dietary considerations address both cardiac and kidney health needs. Activity may be somewhat restricted initially but most cats can return to normal household activity once stabilized. Ongoing vigilance for signs of recurrent thromboembolism is essential.

Prognosis for cats with renal infarction is significantly influenced by the underlying cardiac disease. Cats with mild cardiomyopathy and small renal infarcts may live for years with appropriate management. Those with advanced cardiac disease face higher risk of progressive heart failure and recurrent thromboembolic events. Studies of feline arterial thromboembolism report variable survival times, with some cats living many months to years while others succumb to recurrent events or heart failure despite treatment. The extent of kidney damage affects prognosis for kidney function but is often less limiting than the cardiac disease. Quality of life can be good for cats that respond to treatment and avoid recurrent events.

Long-term outlook requires ongoing management of cardiac disease and acceptance that recurrence risk persists despite preventive therapy. Regular cardiac monitoring through echocardiography helps track disease progression and guides medication adjustments. Kidney function should be periodically reassessed, with chronic kidney disease management implemented if significant function was lost. Some cats remain stable for extended periods while others experience disease progression or complications. Open communication with the veterinary team about changes in the cat's condition enables timely intervention. End-of-life planning discussions are appropriate given the serious nature of the underlying cardiac disease, though many cats enjoy considerable quality time with proper management.

Primary prevention of renal infarction centers on early detection and management of feline cardiomyopathy, the main underlying cause of thromboembolic events. Screening echocardiography for breeds predisposed to hypertrophic cardiomyopathy, including Maine Coon, Ragdoll, and British Shorthair, can identify heart disease before complications occur. Annual veterinary examinations including cardiac auscultation help detect heart murmurs or arrhythmias that warrant further investigation. For cats with diagnosed cardiomyopathy, prophylactic antiplatelet therapy with clopidogrel or aspirin may be recommended to reduce thromboembolic risk, though the optimal prevention protocol remains an area of ongoing research. Early intervention in cardiac disease progression may help reduce the development of conditions that promote thrombus formation.

Environmental prevention strategies support cardiovascular health and reduce stress that may exacerbate cardiac conditions. Maintaining cats at healthy body weight reduces cardiovascular strain. Providing environmental enrichment and stable routines minimizes chronic stress. Ensuring adequate hydration through wet food and multiple water sources supports blood viscosity and cardiovascular function. Avoiding extreme temperature exposure reduces cardiovascular demands. For cats with known cardiac disease, minimizing stressful situations and handling may help prevent acute decompensation or thromboembolic events.

Dietary approaches to prevention focus on supporting overall cardiovascular health. Feeding high-quality, balanced diets appropriate for the cat's life stage provides optimal nutrition. Taurine-complete diets are essential, as taurine deficiency historically caused dilated cardiomyopathy in cats. Omega-3 fatty acid supplementation may have cardiovascular benefits. Appropriate sodium levels support blood pressure management. For cats with established kidney disease, kidney-supportive diets balance cardiac and renal needs. Maintaining lean body condition through portion control reduces cardiovascular strain.

Regular veterinary care enables early detection of cardiac disease and implementation of preventive strategies before complications occur. Annual or more frequent examinations allow for cardiac assessment through auscultation, and abnormal findings prompt further evaluation. Baseline blood work including cardiac biomarkers may detect early cardiac changes. For cats diagnosed with cardiomyopathy, regular echocardiographic monitoring tracks disease progression and helps determine when anticoagulant therapy should be initiated. Blood pressure monitoring identifies hypertension requiring treatment. Proactive management of cardiac disease provides the best opportunity for preventing thromboembolic complications.

Early intervention when cardiac disease is detected is the most effective way to prevent renal infarction and other thromboembolic events. Cats diagnosed with significant cardiomyopathy, particularly those with left atrial enlargement, should be evaluated for antiplatelet therapy even before clinical signs of heart failure develop. Prompt treatment of heart failure when it occurs helps stabilize cardiac function. Education about warning signs of thromboembolism enables owners to seek immediate veterinary care if an event occurs, potentially improving outcomes through rapid intervention. Working with a veterinarian or veterinary cardiologist to develop an individualized monitoring and prevention plan for cats with cardiac disease optimizes the chances of avoiding this serious complication.

Daily management of a cat recovering from or living after renal infarction involves consistent administration of cardiac and anticoagulant medications along with monitoring for complications. Medications must be given at consistent times to maintain therapeutic blood levels. Most cats require clopidogrel daily, and cardiac medications are given according to the prescribed schedule. Owners learn to monitor for signs of bleeding, a potential side effect of anticoagulant therapy, as well as signs suggesting recurrent cardiac or thromboembolic problems. Daily observation of appetite, activity level, breathing rate, and overall comfort helps detect changes requiring veterinary attention. Keeping a log of observations facilitates communication with the veterinary team.

Home environment modifications support cardiovascular health and reduce stress for cats with underlying cardiac disease. Avoiding situations that cause significant stress or excitement helps prevent acute cardiac events. Providing quiet, comfortable resting areas allows cats to rest when needed without exertion. Easy access to food, water, and litter boxes eliminates need for climbing or extended walking that might tire a cat with cardiac disease. Temperature regulation prevents cardiovascular strain from heat or cold stress. For cats with concurrent kidney disease, multiple water stations and wet food encourage hydration.

Maintaining quality of life for cats living after renal infarction balances managing the medical condition with allowing the cat to enjoy normal activities. Most cats can participate in gentle play and normal household activities once stabilized. Appetite should be supported through palatable foods appropriate for any cardiac or kidney dietary restrictions. Grooming assistance helps cats maintain coat condition. Comfortable, warm bedding supports rest. Mental stimulation through window perches, gentle interaction, and environmental enrichment supports wellbeing. Quality of life assessment should be ongoing, with adjustments made as the cat's condition changes.

Ongoing monitoring and veterinary care are essential for managing the complex conditions underlying renal infarction. Regular recheck appointments include cardiac evaluation through examination and periodic echocardiography, kidney function monitoring through blood work, and assessment of anticoagulant therapy effectiveness. Blood pressure monitoring identifies hypertension requiring treatment. Between appointments, owners should contact their veterinarian if they notice changes in breathing rate or effort, decreased appetite, lethargy, signs of pain, changes in limb function or temperature, or any other concerning symptoms. Early intervention for complications improves outcomes.

Caregiver support is important when managing a cat with serious cardiac disease and its complications, as the condition requires vigilance and can be emotionally challenging. Understanding the nature of the underlying disease and the realistic prognosis helps owners make informed decisions and maintain perspective. Connecting with other owners of cats with heart disease through support groups provides understanding and practical advice. Financial planning for ongoing medications, monitoring, and potential emergency care helps reduce stress. The veterinary team serves as a resource for questions, concerns, and support throughout the journey. Honest conversations about prognosis, quality of life, and end-of-life decisions when appropriate help owners prepare for potential outcomes while focusing on providing the best possible care day by day.

Breeds predisposed to hypertrophic cardiomyopathy have elevated risk of renal infarction as a consequence of their cardiac disease. Maine Coon cats have a well-documented genetic predisposition to HCM, with a identified mutation in the MYBPC3 gene present in some affected lines. Genetic testing is available and recommended before breeding. Ragdoll cats also have increased HCM prevalence with a different MYBPC3 mutation identified. British Shorthairs show higher rates of cardiomyopathy compared to mixed-breed cats. Sphynx and Devon Rex breeds have reported increased HCM incidence. Persian cats and related breeds may have elevated risk. Because these breeds are predisposed to the underlying cardiac disease that causes most feline thromboembolic events, they consequently face higher risk of renal infarction.

Beyond specific breed predispositions, any cat with cardiomyopathy faces elevated risk of renal infarction regardless of breed. Mixed-breed cats develop cardiomyopathy and can experience thromboembolic complications. Male cats appear to be affected more frequently than females, though both sexes can develop the condition. Middle-aged to older cats have higher cardiomyopathy prevalence and therefore higher thromboembolic risk. Cats with previously identified heart murmurs, arrhythmias, or other cardiac abnormalities should be evaluated more thoroughly. Any cat with a history of arterial thromboembolism affecting other organs is at high risk for additional events potentially involving the kidneys.

Screening recommendations for at-risk breeds include baseline echocardiography before breeding and regular cardiac screening throughout life. Maine Coon and Ragdoll breeders should perform genetic testing for known HCM mutations and remove positive cats from breeding programs. Screening echocardiography at one year of age and periodically thereafter helps identify affected cats before complications develop. For pet cats from predisposed breeds, discussing cardiac screening with the veterinarian is advisable. Cats found to have cardiomyopathy should be evaluated for anticoagulant therapy to reduce thromboembolic risk. Regular veterinary examinations with cardiac auscultation for all cats helps detect heart disease early, regardless of breed.

Feline cardiomyopathy is the primary condition underlying most cases of renal infarction, with hypertrophic cardiomyopathy being most common. The relationship between cardiac disease and thromboembolic events is well established, with abnormal blood flow in enlarged cardiac chambers promoting clot formation. Management of the underlying cardiac disease is therefore essential for managing and preventing renal infarction. Cats diagnosed with renal infarction should always have thorough cardiac evaluation including echocardiography to characterize the heart disease and guide treatment. The cardiac condition typically determines long-term prognosis more than the renal infarction itself.

Arterial thromboembolism affecting other locations often co-occurs with or precedes renal infarction. Saddle thrombus affecting the distal aorta and causing hind limb paralysis is the most recognized feline arterial thromboembolism presentation. Thromboembolism can also affect brain, mesenteric vessels, or other organs. Cats that experience one thromboembolic event are at high risk for additional events despite preventive therapy. The presence of renal infarction may indicate that subclinical thromboembolic events have occurred or that the cat is at high risk for future events affecting other organ systems. Comprehensive evaluation and aggressive preventive therapy are warranted.

Potential complications of renal infarction include acute and chronic consequences of kidney damage. Acute kidney injury may occur if large portions of kidney tissue are affected or if both kidneys are involved, requiring intensive supportive care. Chronic kidney disease may develop or worsen as a result of lost functional kidney tissue. Hypertension can result from or be exacerbated by kidney damage and requires monitoring and treatment. Recurrent renal infarction can occur despite anticoagulant therapy, causing cumulative kidney damage. Complications related to the underlying cardiac disease, including heart failure and additional thromboembolic events affecting other organs, represent the most serious risks for long-term survival. Comprehensive management addressing all aspects of the cat's cardiovascular and renal health provides the best opportunity for favorable outcomes.