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Background: There is little information on the prevalence of auscultatory abnormalities in anemic cats. This study aimed to describe the prevalence of cardiac murmurs and gallop sounds in a population of anemic and nonanemic cats presenting to an emergency room (ER) and to assess whether the prevalence of auscultatory abnormalities was influenced by the severity of anemia., Key Findings: Records of cats presenting to an ER between May 2021 and May 2022 or receiving a blood transfusion between September 2019 and January 2022 were retrospectively analyzed for presence of a murmur or gallop sound. Cats with known structural heart disease were excluded. A murmur was found in 56 of 185 (30%) anemic cats compared with 11 of 102 (11%) nonanemic cats (p < 0.001), with a higher proportion in cats with PCV <16% (p < 0.001). Twenty-five of 185 (14%) anemic cats had a gallop compared with 4 of 102 (4%) nonanemic cats (p = 0.009), with the highest proportion in cats with PCV 11%-20% (p < 0.001). Echocardiography was performed on 17 of 185 anemic cats; 8 had normal echocardiograms and 9 demonstrated evidence of chamber dilation without left ventricular wall thickening, consistent with anemia., Conclusions: Abnormalities on auscultation are common in anemic cats presenting to the ER, with a higher prevalence in more severely anemic cats., (© Veterinary Emergency and Critical Care Society 2024.)

Introduction: Anterior mitral valve leaflet (AMVL) elongation is a recognised feature of hypertrophic cardiomyopathy (HCM). However, whether AMVL elongation precedes left ventricular hypertrophy in cats is currently unknown. The aim of this study was to explore the risk of developing an HCM phenotype in cats with an elongated AMVL., Animals: FIFTY-FIVE APPARENTLY HEALTHY CATS WITH A NORMAL BASELINE ECHOCARDIOGRAM AND A FOLLOW-UP ECHOCARDIOGRAM AT >ONE YEAR., Materials and Methods: This was a retrospective longitudinal study. Cats at the baseline were grouped based on whether or not they developed an HCM phenotype at follow-up. AMVL length and left atrial and left ventricular dimensions were measured from two-dimensional images., Results: The median follow-up period of the study population was 5.4 years (25th and 75th quartile, 2.7-6.7 years). During this time, 17 cats (30.9%) developed an HCM phenotype. At the baseline, cats that subsequently developed an HCM phenotype had greater AMVL length (9.4 mm [25th and 75th quartile, 9.0-10.6 mm] vs. 8.5 mm [25th and 75th quartile, 7.6-9.1 mm], P < 0.0001) and maximal left ventricular wall thickness (4.5 mm [25th and 75th quartile, 4.1-4.7 mm] vs. 4.0 mm [25th and 75th quartile, 3.7-4.6 mm], P = 0.007) than those that did not. Multiple logistic regression analysis confirmed that both baseline variables were independent predictors for development of an HCM phenotype., Conclusions: The AMVL length was greater in cats that subsequently developed left ventricular hypertrophy. Further studies investigating the clinical application of AMVL in the natural history of feline HCM are warranted., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Background: Whether anemic cats and dogs with increased left heart dimensions are at higher risk of transfusion-associated circulatory overload, and the effect of blood transfusion on left heart dimensions in naturally occurring anemia is unknown., Hypothesis/objectives: To evaluate the effect of blood transfusion on left heart dimensions in clinically relevant anemia., Animals: Twenty dogs and 20 cats presenting to a university veterinary teaching hospital., Methods: In this prospective observational study, anemic dogs and cats requiring blood transfusion were included. Packed cell volume (PCV), total solids, and echocardiography were performed before and within 24 hours of blood transfusion. Signalment, bodyweight, disease process, transfusion duration and volume, and prior treatments were recorded. Nonparametric statistics were reported as median [range]. Post hoc Bonferroni correction set significance at P < .006., Results: After transfusion, PCV increased in cats (12% [6-16] to 18% [10-33], P = .001) and dogs (14% [7-24] to 25% [9-37], P = .001), heart rate decreased in dogs (104 bpm [86-166] to 87 bpm [56-138], P < .001), and fractional shortening decreased in cats (57.1% [36.0-84.7] to 41.0% [28.1-69.6], P = .002) and dogs (33.79% [19.33-62.79] to 31.89% [19.06-51.47], P = .006). Left ventricular internal diameter in systole increased in cats (6.5 mm [2.7-9.8] to 7.9 mm [5.3-11.1], P = .001). Normalized left ventricular internal diameter in diastole (1.48 [1.25-1.79] to 1.57 [1.33-2.00], P = .001) and systole (0.87 [0.58-1.19] to 1.00 [0.74-1.36], P = .001) increased in dogs. Incidence of volume overload did not differ before (14/20 cats, 70%; 9/20 dogs, 45%) or after (12/20 cats, 60%; 11/20 dogs, 55%) transfusion (P = .64)., Conclusions and Clinical Importance: Blood transfusion is well tolerated when signs of volume overload are present before transfusion., (© 2020 The Authors. Journal of Veterinary Internal Medicine published by Wiley Periodicals LLC. on behalf of the American College of Veterinary Internal Medicine.)

Introduction: Supraventricular tachycardia (SVT) has not been well described in cats. The aim of this study was to describe the signalment, clinical findings, and outcome for cats with SVT versus cats with atrial fibrillation (AF)., Animals: Forty-four client owned cats are included in the study. 23 cats with SVT and 21 with AF., Methods: This is a retrospective study. Clinical characteristics were compared between groups using a two-sample t-test or Mann-Whitney U test. Kaplan-Meier survival curves were generated to assess for impact of rhythm diagnosis, presence of ventricular arrhythmia, left atrial diameter, heart rate and congestive heart failure (CHF) status on cardiac death. Differences in survival between groups were compared using Mantel-Cox logrank comparison of Kaplan-Meier survival curves., Results: Cats with supraventricular arrhythmias most commonly presented with respiratory distress (10 of 44 cats). Cats with AF had a slower median heart rate (220 [range: 180-260 beats per minute (bpm)] compared with cats with SVT (300 [range: 150-380] bpm, p < 0.001). All cats with AF had structural heart disease, whereas 4 cats with SVT had no structural abnormalities. Left atrial diameter was significantly larger in cats with AF (23.7 (16.2-40.1) mm compared with 19.1 (12.8-31.4) mm in SVT cats; p = 0.02). Median survival was 58 days (1-780) in cats with AF and 259 days (2-2295) in cats with SVT (p = 0.1). Cats with signs of CHF had a shorter survival time (p = 0.001)., Conclusions: Most cats with AF or SVT have advanced structural heart disease. Some cats with SVT had structurally normal hearts, suggesting that SVT in cats is not always a consequence of atrial enlargement., Competing Interests: Conflicts of Interest Statement The authors do not have any conflicts of interest to disclose., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Background: Left ventricular (LV) systolic dysfunction is associated with increased risk of death in cats with hypertrophic cardiomyopathy (HCM). Mitral and tricuspid annular plane systolic excursion (MAPSE and TAPSE, respectively) are measures of longitudinal systolic function and are reduced in human patients with HCM., Hypotheses: Cats with HCM have lower MAPSE and TAPSE compared to control cats; lower MAPSE and TAPSE are associated with the presence of congestive heart failure (CHF) and reduced survival time., Animals: 64 cats with HCM and 27 healthy cats. Forty-five cats with HCM were not showing clinical signs, and 19 had CHF., Methods: Retrospective study. Anatomic M-mode from the left apical 4-chamber view was used to record MAPSE from the free wall (MAPSE FW) and septum (MAPSE IVS) and TAPSE., Results: Compared to controls, cats with HCM had lower MAPSE IVS (controls 5.2 [4.6-5.6] mm, asymptomatic HCM 4.7 [4.1-5.2] mm, HCM with CHF 2.6 [2.5-3.2] mm, P < .001), MAPSE FW (controls 5.9 [5.3-6.2] mm, asymptomatic HCM 4.7 [4.1-5.1] mm, HCM with CHF 2.8 [2.4-3.2] mm) and TAPSE (controls 8.6 [7.4-10.2] mm, asymptomatic HCM 7.2 [6.3-8.2] mm, HCM with CHF 4.6 [4.1-5.4] mm), with the lowest in the CHF group. Univariate survival analysis showed a shorter survival in cats displaying lower MAPSE IVS, MAPSE FW, and TAPSE., Conclusions and Clinical Importance: MAPSE and TAPSE were lower in cats with HCM than in control cats and were lowest in CHF, suggesting that systolic longitudinal dysfunction is present in cats with HCM. MAPSE and TAPSE have potential prognostic significance., (Copyright © 2017 The Authors. Journal of Veterinary Internal Medicine published by Wiley Periodicals, Inc. on behalf of the American College of Veterinary Internal Medicine.)

A dog or a cat has an incidentally detected heart murmur if the murmuris an unexpected discovery during a veterinary consultation that was not initially focused on the cardiovascular system. This document presents approaches for managing dogs and cats that have incidentally-detected heart murmurs, with an emphasis on murmur characteristics, signalment profiling, and multifactorial decision-making to choose an optimal course for a given patient.

Objectives: There is a growing understanding of the complexity of interplay between renal and cardiovascular systems in both health and disease. The medical profession has adopted the term "cardiorenal syndrome" (CRS) to describe the pathophysiological relationship between the kidney and heart in disease. CRS has yet to be formally defined and described by the veterinary profession and its existence and importance in dogs and cats warrant investigation. The CRS Consensus Group, comprising nine veterinary cardiologists and seven nephrologists from Europe and North America, sought to achieve consensus around the definition, pathophysiology, diagnosis and management of dogs and cats with "cardiovascular-renal disorders" (CvRD). To this end, the Delphi formal methodology for defining/building consensus and defining guidelines was utilised., Methods: Following a literature review, 13 candidate statements regarding CvRD in dogs and cats were tested for consensus, using a modified Delphi method. As a new area of interest, well-designed studies, specific to CRS/CvRD, are lacking, particularly in dogs and cats. Hence, while scientific justification of all the recommendations was sought and used when available, recommendations were largely reliant on theory, expert opinion, small clinical studies and extrapolation from data derived from other species., Results: Of the 13 statements, 11 achieved consensus and 2 did not. The modified Delphi approach worked well to achieve consensus in an objective manner and to develop initial guidelines for CvRD., Discussion: The resultant manuscript describes consensus statements for the definition, classification, diagnosis and management strategies for veterinary patients with CvRD, with an emphasis on the pathological interplay between the two organ systems. By formulating consensus statements regarding CvRD in veterinary medicine, the authors hope to stimulate interest in and advancement of the understanding and management of CvRD in dogs and cats. The use of a formalised method for consensus and guideline development should be considered for other topics in veterinary medicine., (© 2015 The Authors. Journal of Small Animal Practice published by John Wiley & Sons Ltd on behalf of British Small Animal Veterinary Association.)

Background: Population characteristics and outcome of cats with arterial thromboembolism (ATE) managed in general practice (GP) have been poorly described., Hypothesis: Cats with ATE presenting to GP are usually euthanized at presentation, but survival times >1 year are possible., Animals: Cats with ATE managed by 3 GP clinics in the United Kingdom., Methods: Records of cases presenting to GP over a 98-month period (2004-2012) were reviewed. Cats with an antemortem diagnosis of limb ATE were included. Outcome information was obtained., Results: Over 98 months, 250 cats were identified with ATE. Prevalence was approximately 0.3%. At presentation, 153 cats (61.2%) were euthanized, with 68/97 (70.1%) of the remaining cats (27.2% of the total population) surviving >24 hours after presentation. Of these, 30/68 (44.1%) survived for at least 7 days. Hypothermia (HR, 1.44; 95% CI, 1.002-2.07; P = .049) and management by Clinic 2 (HR, 5.53; 95% CI, 1.23-24.8; P = .026) were independent predictors of 24-hour euthanasia or death. For cats surviving >24 hours, hypothermia (HR, 2.25; 95% CI, 1.12-4.48; P = .021) and failure to receive aspirin, clopidogrel, or both (HR, 8.26; 95% CI, 1.39-50; P = .001) were independent predictors of euthanasia or death within 7 days. For cats that survived ≥7 days, median survival time was 94 (95% CI, 42-164) days, with 6 cats alive 1 year after presentation., Conclusions: Although 153/250 cats were euthanized at presentation, 6 cats survived >12 months. No factors were identified that predicted euthanasia on presentation., (Copyright © 2013 by the American College of Veterinary Internal Medicine.)

Objectives: To investigate the effect of treatment with atenolol on 5-year survival in cats with preclinical hypertrophic cardiomyopathy (HCM)., Animals: 63 Client-owned cats with preclinical HCM and 31 healthy control cats., Methods: Prospective, observational, open-label, clinical cohort study. Cats with HCM were diagnosed by echocardiography, treated with atenolol (6.25-12.5 mg q12h, PO; n = 42) or untreated (n = 21), and were observed for 5 years after enrollment. The study end point was death from any cause. Cats of similar body weight, age, gender, and breed without evidence of heart disease were studied concurrently and served as controls., Results: During the observational period, 27 cats with HCM died; 14 (22%) due to cardiac disease and 13 (21%) due to non-cardiac disease. Ten control cats (32%) died of non-cardiac disease. There was no significant difference (P = 0.307) in all-cause mortality between control and HCM. Cardiac mortality was higher in cats with HCM compared to control cats (P = 0.005). There was no significant difference in all-cause mortality (P = 0.729) and cardiac mortality (P = 0.897) between cats with HCM treated or untreated with atenolol. Age and left atrial size at diagnosis were the only predictors of 5-year outcome., Conclusions: Our study failed to demonstrate an effect of atenolol on 5-year survival in cats with preclinical HCM., (Copyright © 2013 Elsevier B.V. All rights reserved.)

Although sedation is frequently used to facilitate patient compliance in feline echocardiography, the effects of sedative drugs on echocardiographic variables have been poorly documented. This study investigated the effects of two sedation protocols on echocardiographic indices in healthy cats, with special emphasis on the assessment of left atrial size and function, as well as left ventricular diastolic performance. Seven cats underwent echocardiography (transthoracic two-dimensional, spectral Doppler, color flow Doppler and tissue Doppler imaging) before and after sedation with both acepromazine (0.1 mg/kg IM) and butorphanol (0.25 mg/kg IM), or acepromazine (0.1 mg/kg IM), butorphanol (0.25 mg/kg IM) and ketamine (1.5 mg/kg IV). Heart rate increased significantly following acepromazine/butorphanol/ketamine (mean±SD of increase, 40±26 beats/min) and non-invasive systolic blood pressure decreased significantly following acepromazine/butorphanol (mean±SD of decrease, 12±19 mmHg). The majority of echocardiographic variables were not significantly different after sedation compared with baseline values. Both sedation protocols resulted in mildly decreased left ventricular end-diastolic dimension and mildly increased left ventricular end-diastolic wall thickness. This study therefore failed to demonstrate clinically meaningful effects of these sedation protocols on echocardiographic measurements, suggesting that sedation with acepromazine, butorphanol and/or ketamine can be used to facilitate echocardiography in healthy cats.

Objectives: This pilot study was performed to investigate murmur prevalence and to explore the association between auscultatory and echocardiographic findings in apparently healthy cats in order to design a larger study., Animals, Materials and Methods: Adult cats in 4 rehoming centres were screened by auscultation and echocardiography (echo) over 2 periods of 2 weeks each. In the first period, echo was attempted only in cats with murmurs. In the second period, all cats underwent auscultation by 2 observers and echo. LVH was defined in 5 ways: maximal diastolic left ventricular (LV) wall thickness ≥ 6 mm or ≥ 5.5 mm with 2D (LVH(6 2D), LVH(5.5 2D), respectively) or M-Mode echo (LVH(6 MM) or LVH(5.5 MM) respectively), or LV wall thickness ≥ 6 mm (2D) for >50% of a wall segment (LVH(50%))., Results: 67/199 (34%) cats had a murmur. Interobserver agreement on murmur presence was moderate (κ 0.47). 61 cats with a murmur and 31 cats without underwent both auscultation and echo. Depending on the criteria, LVH was present in 31 (LVH(6 2D)), 21 (LVH(50%)) and 11 (LVH(6 MM)) scanned cats. 18-62% of cats with murmurs had LVH, depending on the echo criteria used. Agreement was best between observers in identifying LVH using LVH(6 2D) and LVH(50%) (κ = 1.0)., Conclusions: Heart murmurs are common in apparently healthy cats. The prevalence of LVH varies depending on the criteria used., (Copyright © 2010 Elsevier B.V. All rights reserved.)

Objective: To determine if serum cardiac troponin I (cTnI) concentrations can distinguish cardiac from non-cardiac causes of respiratory distress (RD) in cats., Animals, Materials and Methods: 53 cats. cTnI concentrations were measured in 30 cats with non-cardiac respiratory distress (RD-NC) and compared to 23 cats with RD due to congestive heart failure (RD+CHF)., Results: The RD+CHF group had higher median cTnI concentration (0.94 ng/ml interquartile range IQR 0.54-4.00, range < 0.20-90.14) than the RD-NC group (< 0.2 ng/ml IQR < 0.2-0.33, range < 0.20-41.1, p<0.001). The area under the curve (AUC) was 0.842 (95% CI 0.728-0.955) for the receiver operator curve (ROC) analysis of the accuracy of cTnI concentrations to discriminate RD+CHF from RD-NC cats. A cut-off of > or = 0.81 ng/ml discriminated RD+CHF from RD-NC cats with a sensitivity and specificity of 65.2% and 90.0% respectively. However considerable overlap in cTnI concentrations between the 2 groups was identified., Conclusions: Serum cTnI concentrations were different in RD+CHF compared to RD-NC cats. However the overlap in cTnI concentrations between the 2 groups reduced the clinical efficacy of the assay which therefore should not be used as a stand-alone test but in combination with other diagnostics such as echocardiography and radiography.

Objectives: To determine if serum natriuretic peptide (NP) concentrations could distinguish cardiac from non-cardiac causes of respiratory distress (RD) in cats., Animals: Seventy-four cats from 1 university hospital were used., Methods: Serum NP concentrations were measured in 41 cats with non-cardiac respiratory distress (RD-NC) and compared to 33 cats with RD due to congestive heart failure (RD+CHF) using sandwich enzyme immunoassays (ELISA)., Results: RD-NC cats had lower (P=0.0001) median NT-proANP and NT-proBNP concentrations (614 and 45 fmol/mL, respectively) than RD+CHF cats (1690 and 523 fmol/mL, respectively). The area under the curve was 0.88 and 0.96 for the receiver operating curve analysis of the diagnostic accuracy of NT-proANP and NT-proBNP concentrations to discriminate RD+CHF from RD-NC cats (P=0.036). An optimum cut-off concentration of 986 fmol/mL for NT-proANP and 220 fmol/mL for NT-proBNP accurately discriminated RD-NC from RC+CHF cats with a sensitivity of 93.8% and 93.9% and a specificity of 80.3% and 87.8%, respectively., Conclusions: Serum NP concentrations were different in RD+CHF cats compared to RD-NC cats. Evaluation of circulating NP concentrations may be helpful in the initial approach to cats presenting with respiratory distress, particularly if advances in ELISA technology result in a rapid cage-side test.

Objective: To review the pathophysiology, clinical signs, diagnosis, and treatment of pulmonary thromboembolism (PTE) in small animals., Data Sources: Human and veterinary clinical studies, reviews, texts, and recent research in canine and feline PTE diagnosis and thromboembolic therapeutics., Human Data Synthesis: In humans, clinical probability assessment and point-of-care D-dimer-based algorithms are widely used. Computed tomography pulmonary angiography is the gold standard for PTE diagnosis in humans. Echocardiography is increasingly used for bedside assessment of affected patients. In low-risk human patients anticoagulants alone are recommended while patients with cardiogenic shock are treated with thrombolytics followed by anticoagulation., Veterinary Data Synthesis: PTE is associated with numerous predisposing conditions causing hypercoagulability, blood flow stasis, or endothelial injury. Identifying at-risk patients is key to diagnosis in small animals. Thromboelastography provides a method for identifying hypercoagulable patients. Computed tomography pulmonary angiography may replace selective pulmonary angiography as the imaging technique of choice for PTE diagnosis. PTE therapy consists of supportive treatment combined with appropriate, individualized thromboembolic pharmacotherapy for acute treatment and chronic management. Thrombolytic therapy for PTE remains controversial but may be indicated in hemodynamically unstable acute PTE. Thromboprophylaxis in specific conditions is rational although evidence of efficacy is limited. Prognosis depends upon degree of cardiopulmonary compromise and patient response to therapy. Mortality rates in small animals are unknown., Conclusions: New diagnostic techniques and advances in therapy offer significant potential for improvements in the identification and treatment of PTE in small animals. Further study must be directed to validating new diagnostic modalities and evaluating therapeutic regimes.

Background: Circulating natriuretic peptide concentrations are increased in cats with myocardial dysfunction., Hypothesis: Serum N-terminal fragment of proatrial natriuretic peptide (NT-proANP) and NT-probrain natriuretic peptide (proBNP) concentrations may predict the presence of heart disease (HD) and congestive heart failure (CHF). A positive relationship is also predicted among natriuretic peptide (NP) concentrations, a noninvasive estimate of left ventricular filling pressure (E/E(a)), and an echocardiographic measure of left atrial (LA) size (LA/aortic diameter [Ao])., Methods: Serum NP concentrations were measured in 28 healthy control and 50 study cats using sandwich enzyme immunoassays. The study group comprised cats, with HD but no CHF (HD - CHF, n = 17) and cats with CHF (HD + CHF, n = 33). The relationship among NP concentrations, LA size, and E/E(a) was examined. The ability of NP to distinguish control from study cats, and HD - CHF from HD + CHF cats, was explored using receiver operator curve analysis., Results: NP concentrations were significantly lower in control than in study cats (P= .0001). The NT-proBNP concentrations were positively correlated with LA/Ao ratio (rho= 0.34; P= .02) and with E/E(a) ratio (rho= 0.68; P < .05). An NT-proBNP concentration of 49 fmol/mL gave a sensitivity and specificity of 100 and 89.3%, respectively, for correctly distinguishing 96.2% of control from study cats. Pairwise comparisons of the areas under the curve identified a statistically significant difference (P= .011) between NT-proANP and NT-proBNP to distinguish control from study cats. NT-proANP and NT-proBNP concentrations were significantly higher in HD + CHF cats than in HD - CHF cats (P= .0023 and .0001, respectively)., Conclusions: Serum concentrations of NT-proANP and particularly NT-proBNP were different in healthy control cats, asymptomatic cats with HD, and cats with CHF, suggesting that measurement of NP concentrations may prove clinically useful as an initial screening test for cats with suspected cardiac disease.

Background: Double-chambered right ventricle (DCRV) is a frequently recognized cardiac congenital abnormality in humans. It has been described in dogs and in 1 cat. However systemic description of clinical and echocardiographic features of the disease in cats is currently lacking from the veterinary literature., Animals: Nine cats with DCRV are described., Results: The cats ranged from 4 months to 10 years of age. Eight cats at presentation were asymptomatic and 1 cat had chylothorax. In all cases echocardiography revealed abnormal fibromuscular bundles obstructing the mid-right ventricle, dividing the chamber into 2 compartments. The proximal right ventricular compartment was markedly hypertrophied, and right atrial dilation was usually present. The mean pressure gradient measured across the stenotic area was 130 +/- 50 mm Hg. Concurrent abnormalities included a ventricular septal defect (n = 2); aortic malalignment, aortic insufficiency (n = 1); and congenital peritoneal-pericardial diaphragmatic hernia (n = 1). Two cats had systolic anterior motion of the mitral valve, one of which had concurrent left ventricular hypertrophy. Five cats have remained asymptomatic for a median period of 3.6 years (range, 3.3-5 years) and 3 cats have developed clinical signs associated with congestive heart failure (at 2, 3.3, and 9 years). One cat showed progressive lethargy and exercise intolerance and underwent partial ventriculectomy at the age of 2 years. This cat died during the operation with electromechanical dissociation., Conclusions: DCRV is a congenital cardiac abnormality that may be more common than previously recognized.

Pimobendan is an oral inodilator compound available in many countries for use in canine heart failure. It combines calcium-sensitizing effects with PDE III inhibition, resulting in positive inotropic effects and veno- and ergic signal transduction pathway in the failing heart, the calcium-sensitizing effects may assume greater importance in patients with heart failure. Clinical studies in human patients have shown sustained improvement in hemodynamics and exercise tolerance, with favorable neurohormonal effects. One study showed a nonsignificant trend toward increased mortality [20], but proarrhythmic effects have not ben observed. Studies in naturally occurring canine heart failure suggest that pimobendan's effects are at least comparable to those of ACE inhibitors, if not superior. Pimobendan is likely to play an increasing role in the future in the treatment of canine heart disease., (Copyright 2004 Elsevier Inc.)

Feline asthma syndrome (FAS) is a clinical condition characterised by recurrent bouts of coughing, wheezing and, or, dyspnoea. While the aetiology is unproven, the condition is believed to involve a type I immediate hypersensitivity reaction to inhaled allergens. In this paper the clinical data from 29 cats, where a diagnosis of FAS was made, are assessed retrospectively. The most common clinical presentation was recurrent bouts of coughing (n = 26) and dyspnoea (n = 21). Radiographic changes were noted in 24 cats, which included increased bronchial (n = 5), interstitial (n = 7) and mixed (n = 12) (bronchial and interstitial) patterns. Right middle lung lobe collapse was noted in two cats. Abnormal bronchial cytology was present in 16 cats. A predominant eosinophilic sample was collected in only three cats. There were minimal changes in differential white cell counts, and mild eosinophilia was found in only five cats. Prednisolone alone was the most effective therapy, although avoidance of putative aeroallergens and antibacterial therapy was effective in some. On the basis of the data from these cases it would appear that the diagnosis of FAS depends largely on the clinical presentation and radiographic findings. The value of ancillary tests in the diagnosis of FAS appears to be limited.