Congestive Heart Failure In Cats Research Articles

Radiographic findings of cardiopulmonary structures can predict hypertrophic cardiomyopathy and congestive heart failure in cats.

This study aimed to find the radiographic characteristics for the detection of hypertrophic cardiomyopathy (HCM) and congestive heart failure (CHF) in cats. Healthy cats (n = 35) and HCM cats with (21) and without (22) CHF. On radiography, the cardiac size using vertebral heart score, left atrium enlargement (LAE), and dilation of the pulmonary vessels were assessed. The sensitivity and specificity of the radiographic characteristics regarding LAE were evaluated with the echocardiographic left atrium to aortic root ratio as a reference. In HCM cats, cardiomegaly, LAE, and dilation of the caudal pulmonary artery were found compared with those in healthy cats. The LAE could be predicted using the elevation of the carina with 94.12% specificity but 17.5% sensitivity. When CHF developed, LAE and dilation of the caudal pulmonary vein (PV) were significantly different compared with those in HCM cats without CHF. The distal side of the summated shadow made by the right caudal PV with the ninth rib in HCM cats with CHF was significantly larger than that in HCM cats without CHF and a cut-off value of 5.35 mm was drawn with 75% sensitivity and 100% specificity. Although there was an overlapping of radiographic findings between healthy and HCM cats, radiographic assessment of LAE can be useful for predicting HCM and the distal side of the summated shadow made by the right caudal PV with the ninth rib can predict CHF in HCM cats.

EFFECTIVENESS OF PIMOBENDAN IN CATS WITH CARDIOGENIC ARTERIAL THROMBOEMBOLISM

Cardiogenic arterial thromboembolism (CATE) is a common complication of cardiomyopathy in cats. Current research is aimed at developing effective protocols for the therapy and prevention of CATE. The main focus is on finding effective anticoagulants, antiaggregants, and methods that improve blood supply to the affected area. At the same time, interest in the use of pimobendan for the therapy of congestive heart failure in cats has increased among researchers. Published works show an increase in life expectancy in cats with hypertrophic cardiomyopathy (HCM) and a positive effect on left atrial function. Therefore, the study of the effect of pimobendan on life expectancy, the occurrence of relapses in cats according to CATE is relevant and became the goal of this work. The study included 24 animals that had a CATE incident due to HCM and lived more than 2 weeks after the crisis. Two groups were formed: the first - 13 cats that after stabilization of the condition received standard therapy (furosemide, ACE inhibitor, clopidogrel) and pimobendan; the second - 11 cats that received only standard therapy. The anamnesis, clinical examination, echocardiographic examination, and information about relapse, death or euthanasia were recorded in the animals. 91.7% of cats were males, the average age was 7 ± 0.7 years. Dyspnoea, pulmonary edema, hypothermia, change in mental status, paresis and anemia of the affected limb were found in the majority. Two pelvic limbs were more often affected. Relapse occurred in 37.5% of subjects. The time interval from the incident to the recurrence in the first group was 387.4 ± 104.5 and in the second 107.2 ± 32.1 days. Euthanasia was performed for 20.8% of animals and was always associated with relapse. The survival time in the first group averaged 403.7 ± 104.0, and in the second - 314 ± 47.3 days. The median survival time for the first group is 9.5 months and for the second 12.5. After the death of all the animals in the first group, 40% of cats who received pimobendan remained alive. We didn`t find statistical differences between the groups in the number of relapses, euthanasias, duration of life and survival. Was found a significant difference in the length of time before relapse. Pimobendan did not show a negative effect on life expectancy in cats according to CATE. The positive effect is probably not clear enough and needs to be studied in a larger cohort of animals.

Detection of Congestive Heart Failure and Myocardial Dysfunction in Cats With Cardiomyopathy by Using Two-Dimensional Speckle-Tracking Echocardiography.

Congestive heart failure (CHF) is a life-threatening condition in cats with cardiomyopathy. We hypothesized that myocardial dysfunction may induce progression to CHF pathophysiology in cats with cardiomyopathy. However, no previous studies have evaluated the involvement of myocardial dysfunction in cats with CHF. In this study, we aimed to evaluate the relationship between CHF and myocardial function assessed using two-dimensional speckle-tracking echocardiography (2D-STE). Sixteen client-owned healthy cats and 32 cats with cardiomyopathy were enrolled in this study. Cats were classified into three groups: healthy cats, cardiomyopathy without CHF (CM group), and cardiomyopathy with CHF (CHF group). Left ventricular (LV) longitudinal and circumferential strains (SL and SC, respectively), and right ventricular (RV) SL were measured using 2D-STE. Logistic regression analysis was performed to assess the relationship between CHF and echocardiographic variables, including 2D-STE. Results comparing the healthy cats and CM vs. CHF groups showed that increased left atrial to aortic diameter ratio and decreased LV apical SC were significantly associated with the existence of CHF (odds ratio [95% confidence interval]: 1.40 [1.16–1.78] and 1.59 [1.06–2.36], respectively). Results comparing the CM vs. CHF group showed that increased end-diastolic RV internal dimension and decreased RV SL were significantly associated with the existence of CHF (odds ratio: 1.07 [1.00–1.13] and 1.34 [1.07–1.68], respectively). Left atrial enlargement and depressed LV apical myocardial function may be useful tools for predicting the progression to CHF in cats. Furthermore, RV enlargement and dysfunction may lead to the onset of CHF in asymptomatic cats with cardiomyopathy.

Detection of congestive heart failure by mitral annular displacement in cats with hypertrophic cardiomyopathy – concordance between tissue Doppler imaging–derived tissue tracking and M-mode

IntroductionThe left ventricular systolic longitudinal function, traditionally measured by M-mode–derived mitral annular plane systolic excursion (MAPSE), is reduced in feline hypertrophic cardiomyopathy (HCM) and further reduced in cats with left-sided congestive heart failure (CHF). The objectives of this study were to compare longitudinal displacement measured by tissue tracking (TT-LD) and MAPSE in feline HCM and assess these methods’ ability to differentiate CHF from preclinical HCM. A further objective was to provide preliminary reference intervals for TT-LD. AnimalsEighty-five client-owned cats. MethodsA retrospective case–control study. Anatomical M-mode was used to record MAPSE, and TT-LD was recorded by tissue tracking. ResultsReduced longitudinal displacement measured by either MAPSE or TT-LD was significantly associated with CHF in cats with HCM (p < 0.036). Receiver-operating characteristic analysis indicated that TT-LD (AUC: 92.9%–97.9%) was more sensitive and specific than MAPSE (AUC: 85.8%–89.1%) for the detection of CHF. A diagnostic cut-off of 2.89 mm for maximal TT-LD in the left ventricular septum resulted in a sensitivity and specificity of 100% and 83.3%, while a diagnostic cut-off of 2.41 mm in the left ventricular posterior wall resulted in a sensitivity of 100% and a specificity of 90%. ConclusionsM-mode–derived mitral annular plane systolic excursion and TT-LD were strongly correlated, but not interchangeable. Longitudinal displacement measured by tissue tracking decreased more with disease severity than traditional MAPSE. Longitudinal displacement may help detect CHF in cats with HCM – with the maximal TT-LD of the left ventricular posterior wall achieving the highest AUC value.

Cardiovascular-renal axis disorder and acute-phase proteins in cats with congestive heart failure caused by primary cardiomyopathy.

BackgroundCurrently, the pathogenesis of congestive heart failure (CHF) in cats is not fully understood.ObjectiveTo identify novel biomarkers for CHF in cats caused by primary cardiomyopathy, particularly related to cardiovascular‐renal axis disorder and systemic inflammatory response.AnimalsTwenty‐five cats in CHF caused by primary cardiomyopathy, 12 cats with preclinical cardiomyopathy, and 20 healthy controls.MethodsCase control and observational case series. The following serum biomarkers were compared among the 3 cat groups: a cardiorenal profile that included N‐terminal pro‐brain natriuretic peptide (NT‐proBNP), symmetric dimethylarginine (SDMA), and creatinine and an inflammatory profile that included 7 acute‐phase proteins (APPs). Survival analyses and longitudinal studies were performed in CHF cats.ResultsAll cardiorenal biomarkers were positively correlated and higher in CHF cats, and high NT‐proBNP and SDMA were associated with poor clinical outcome. Cats with CHF had significantly higher leucine‐rich alpha‐2‐glycoprotein 1, serum amyloid A, and ceruloplasmin, and these APPs were positively correlated with NT‐proBNP and left atrial size. In a multivariable survival analysis, alpha‐1‐acid glycoprotein concentration (P = .01), body weight (P = .02) and left atrial‐to‐aortic root ratio (P = .01) were independent prognostic factors for CHF in these cats.Conclusions and Clinical ImportanceIn cats, CHF is an inflammatory disorder and outcome in CHF may be determined by the extent of inflammation and possibly the amount of residual renal function. These novel biomarkers have potential use for the clinical management, prognosis, and future research into CHF and cardiomyopathy in cats.

Detection of congestive heart failure by Doppler echocardiography in cats with hypertrophic cardiomyopathy.

BackgroundLeft‐sided congestive heart failure (CHF) is characterized by increased filling pressures and related Doppler echocardiographic (DE) filling patterns.HypothesisDoppler echocardiographic variables of left ventricular filling derived from transmitral flow, pulmonary vein flow, and tissue Doppler can be used to detect CHF in cats with hypertrophic cardiomyopathy (HCM).AnimalsForty‐seven client‐owned cats.MethodsProspective clinical cohort study. Cats underwent physical examination, thoracic radiography, analysis of N‐terminal pro‐brain natriuretic peptide (NT‐proBNP), and transthoracic echocardiography and were divided into 3 age‐matched groups: Group 1 (apparently healthy control), Group 2 (preclinical HCM), and Group 3 (HCM and CHF). Measured and calculated variables included respiratory rate, DE estimates, serum NT‐proBNP concentration, and radiographic CHF score. Groups were compared using ANOVA, and receiver operating characteristic (ROC) curve and multivariate analyses were used to identify diagnostic cutoffs for the detection of CHF.ResultsFifteen cats were in Group 1, 17 in Group 2, and 15 in Group 3. The ROC analysis indicated that the ratio of peak velocity of early diastolic transmitral flow to peak velocity of late diastolic transmitral flow (area under the curve [AUC], 1.0; diagnostic cutoff, 1.77; P = .001), ratio of left atrial size to aortic annular dimension (AUC, 0.91; diagnostic cutoff, 1.96; P = .003), left atrial diameter (AUC, 0.89; cutoff, 18.5 mm; P = .004), diastolic functional class (AUC, 0.89; cutoff, class 2; P = .005), respiratory (AUC, 0.79; cutoff, 36 breaths per minute [brpm]; P = .02), and the ratio of the peak velocity of fused early and late transmitral flow velocities to the peak velocity of the fused early and late diastolic tissue Doppler waveforms (AUC, 0.74; cutoff, 15.1; P = .05) performed best for detecting CHF.Conclusions and Clinical ImportanceVarious DE variables can be used to detect CHF in cats with HCM. Determination of the clinical benefit of such variables in initiating treatments and assessing treatment success needs further study.

Echocardiographic and biomarker evidence of plasma volume expansion after short-term steroids administered orally in cats.

BackgroundSteroids administered PO and intramuscularly are associated with development of congestive heart failure in cats without prior signs of heart disease, but criteria to identify cats at increased risk for steroid‐induced heart failure are not established.HypothesisCats administered steroids PO for 5 to 7 days will develop increased N terminal pro‐B‐type natriuretic peptide (NT‐proBNP) concentration and heart size.AnimalsTen client‐owned cats.MethodsObservational cohort study. Cats intended to initiate at least a 5‐day course of steroids administered PO were consecutively recruited.ResultsSteroids administered PO to cats are not associated with differences in absolute concentration of NT‐proBNP (baseline: 49 pmol/L [range, 24‐1013]; after steroids: 85 pmol/L [range, 46‐1367]; P = .23), blood pressure (baseline: 145 mm Hg [range, 116‐163]; after steroids: 145 mm Hg [range, 115‐230]; P = .94), nor blood glucose concentration (baseline: 125 mg/dL [range, 92‐254]; after steroids: 144 mg/dL [range, 114‐307]; P = .43), but are associated with increased median left atrial dimension (baseline: 1.26 cm [range, 0.96‐2.03; after steroids: 1.38 [range, 1.03‐2.20]; P = .02) and mean left ventricular internal diameter (baseline: 1.55 cm [standard deviation—SD, 0.28; after steroids: 1.72 cm [SD, 0.28]; P = .03). Six of 10 (60%) cats had a percentile change in NT‐proBNP >60% after steroids, and 3 of 8 (38%) cats with baseline BNP <100 pmol/L had an NT‐proBNP >100 pmol/L after steroids.Conclusions and Clinical ImportanceIncreased heart size and percentage change in individual NT‐proBNP concentration suggests plasma volume expansion secondary to steroids administered PO in cats. A serial assessment of an individual cat's change in NT‐proBNP might be clinically useful for judging risk for volume expansion.

Left atrial size and volume in cats with primary cardiomyopathy with and without congestive heart failure

Introduction/objectivesMyocardial diseases are the most common acquired cardiac diseases in cats and may result in left atrial enlargement and congestive heart failure (CHF). Volume calculations have replaced linear measurements for chamber quantification in humans but are not commonly measured in cats. The aims of this retrospective study were to compare the left atrial (LA) size by two-dimensional linear measurements to two-dimensional LA volumes (LAV). AnimalsOne hundred sixty-two client-owned cats were included. Materials and methodsCats with complete echocardiographic examinations were included and categorized into one of the three groups: healthy, cardiomyopathy (CM), and CHF. Seven measurements of the LA size were performed including minimal and maximal LA-to-aortic ratio (LA:Ao) and LAV and also maximal left atrial diameter (LAD). ResultsCats were classified as healthy (n = 56), CM (n = 62), and CHF (n = 44). The minimal LA:Ao (LA:Aomin) and minimal LAV from the left apical view (LAVmin-LAP) best differentiated the CM and CHF groups. The LA:Aomin value with the optimal sensitivity and specificity to distinguish CM and CHF cats was 1.64 (sensitivity 84% and specificity 75%). ConclusionsLeft atrial volumes were not superior to linear measurements of LA size in distinguishing CM and CHF cats in this study. Minimal LA size and volumes resulted in a larger area under the curve than each corresponding maximal value. Minimum LA size may be a better prognostic factor of CHF in cats with CM.

Evaluation of point-of-care thoracic ultrasound and NT-proBNP for the diagnosis of congestive heart failure in cats with respiratory distress.

BackgroundThe diagnosis of congestive heart failure (CHF) in cats is challenging. Point‐of‐care (POC) thoracic ultrasound and NT‐proBNP testing are emerging tools that may aid in diagnosis.Hypothesis/ObjectivesTo assess the diagnostic accuracy of POC lung ultrasound (LUS), focused cardiac ultrasound (FCU), and NT‐proBNP in predicting a final diagnosis of CHF.AnimalsFifty‐one cats in respiratory distress.MethodsBlood NT‐proBNP, LUS, and FCU evaluating left atrial (LA) size and presence of pericardial effusion (PCEFF) were performed in all cats. Lung ultrasound findings including pleural effusion (PLEFF), number of B‐lines, and sub‐pleural abnormalities were noted. Medical records were evaluated for final diagnosis.ResultsThirty‐three of 51 (65%) cats were diagnosed with CHF. Lung ultrasound and blood NT‐proBNP were significant predictors of CHF in a multivariate model. The LUS criterion that maximized accuracy for CHF diagnosis was presence of >1 site strongly positive for B‐lines (>3 B‐lines per site), resulting in sensitivity of 78.8%, specificity of 83.3%, and area under the curve (AUC) of 0.833. Subjective LA enlargement was 97.0% sensitive and 100% specific for CHF (AUC 0.985). Presence of PCEFF also was 100% specific, but only 60.6% sensitive, for CHF (AUC 0.803). A positive blood NT‐proBNP test was 93.9% sensitive and 72.2% specific for the diagnosis of CHF (AUC 0.831).Conclusions and Clinical ImportancePoint‐of‐care diagnostic techniques of LUS, FCU, and NT‐proBNP are useful to diagnose CHF in cats with respiratory distress.

Detection of intra-cardiac thrombi and congestive heart failure in cats using computed tomographic angiography.

Arterial thromboembolism is a life-threatening condition in cats most commonly secondary to cardiac disease. Echocardiography is the reference standard to evaluate for presence of a thrombus. In humans, computed tomographic (CT) angiography is becoming widely used to detect left atrial thrombi precluding the use of sedation. The purpose of this prospective, controlled, methods comparison pilot study was threefold: (1) describe new CT angiography protocol used in awake cats with cardiac disease and congestive heart failure; (2) determine accuracy of continuous and dynamic acquisition CT angiography to identify and characterize cardiac thrombi from spontaneous echocardiographic contrast using transthoracic echocardiography as our reference standard; (3) identify known negative prognostic factors and comorbidities of the thorax that CT angiography may provide that complement or supersede echocardiographic examination. Fourteen cats with heart disease were recruited; 7 with thrombi and 7 with spontaneous echocardiographic contrast. Echocardiography and awake CT angiography were performed using a microdose of contrast. Six of 7 thrombi were identified on CT angiography as filling defects by at least one reviewer within the left auricle (n=6) and right heart (n=1). Highest sensitivity (71.4%) was in continuous phase and highest specificity (85.7%) was in dynamic studies with fair to moderate interobserver agreement (0.38 and 0.44). CT angiography identified prognostic cardiac information (left atrial enlargement, congestive heart failure, arterial thromboembolism) and comorbidities (suspected idiopathic pulmonary fibrosis, asthma). This study indicates CT angiography can readily identify cardiac thrombi, important prognostic information and comorbidities, and can be safely performed in cats with cardiac disease and congestive heart failure.

Retrospective evaluation of the incidence and prognostic significance of spontaneous echocardiographic contrast in relation to cardiac disease and congestive heart failure in cats: 725 cases (2006-2011).

To determine whether the presence of spontaneous echocardiographic contrast (SEC) in cats with cardiomyopathy is associated with increased mortality. To establish whether specific types of cardiomyopathy are more often associated with SEC in an attempt to provide a risk-stratification scheme for cats with increased risk of thromboembolic events. Retrospective study 2006-2011. Tertiary referral and teaching hospital. Seven hundred twenty-five client-owned cats undergoing echocardiographic evaluation. Patient characteristics, including age, breed, clinical signs, type of cardiovascular disease, presence of SEC, and survival time were recorded. Thyroxine, HCT, and blood pressure were recorded when available. Among cats diagnosed with cardiac abnormalities based on echocardiographic findings, those with SEC were at significantly increased risk of death as compared to those without SEC. Cats with dilated cardiomyopathy, unclassified cardiomyopathy, and hypertrophic cardiomyopathy were significantly more likely to have SEC compared to cats with other types of cardiac disease. Cats with cardiomyopathy and SEC have an increased risk of death compared to cats without SEC, although other previously identified factors such as the presence of congestive heart failure and increased left atrium to aorta ratio remain important determinants of mortality. Cats with hypertrophic cardiomyopathy, unclassified cardiomyopathy, and dilated cardiomyopathy may benefit from anticoagulant therapy due to the increased risk of SEC in these subpopulations.

Increased normalized pulmonary transit times and pulmonary blood volumes in cardiomyopathic cats with or without congestive heart failure

ObjectivesTo estimate heart rate-normalized pulmonary transit times (nPTTs) in cardiomyopathic cats with or without congestive heart failure (CHF). To assess potential associations of echocardiographic variables and nPTT and to evaluate nPTT as a test for the presence of CHF. AnimalsForty-eight privately owned cats. MethodsnPTT was measured using echocardiography and the ultrasound contrast media SonoVue® in 3 groups of cats: healthy cats (group 1), cats with cardiomyopathy (CM) but without CHF (group 2), and cats with CM and CHF (group 3). Interrelations between pulmonary blood volume (PBV), nPTT, stroke volume (SV), and echocardiographic variables were investigated by means of linear univariate and multivariate analysis. ResultsMedian nPTT values in group 1, group 2, and group 3 were 3.63 (interquartile range [IQR], 3.20–4.22), 6.09 (IQR, 5.0–7.02), and 8.49 (IQR, 7.58–11.04), respectively. Values were significantly different between all 3 groups. Median PBVs in group 1, group 2, and group 3 were 27.94 mL (IQR, 21.02–33.17 mL), 42.83 mL (IQR, 38.46–50.36 mL) and 49.48 mL (IQR, 38.84–64.39 mL). SV, PBV, and shortening fraction <30% were significant predictors of nPTT. nPTT and left atrial to aortic root (LA:AO) ratio, not SV, were the main predictors of PBV. ConclusionnPTT may be useful as a test for the presence of CHF in cats with CM and as a measure of cardiac performance. nPTT and LA:AO ratios predict CHF with equal accuracy. Increased PBV is significantly associated with higher nPTT and LA:AO ratios.

RADIOGRAPHIC AND ECHOCARDIOGRAPHIC ASSESSMENT OF LEFT ATRIAL SIZE IN 100 CATS WITH ACUTE LEFT‐SIDED CONGESTIVE HEART FAILURE

The aims of this study were to evaluate left atrial size in cats with acute left-sided congestive heart failure. We hypothesized that left atrial size as determined by thoracic radiography can be normal in cats with acute left-sided congestive heart failure. One hundred cats with acute left-sided congestive heart failure in which thoracic radiography and echocardiography were performed within 12 h were identified. Left atrial size was evaluated using right lateral and ventrodorsal radiographs. Measurements were compared to two-dimensional echocardiographic variables of left atrial size and left ventricular size. On echocardiography, left atrial enlargement was observed in 96% cats (subjective assessment) whereas maximum left atrial dimension was increased (>15.7 mm) in 93% cats. On radiographs left atrial enlargement (subjective assessment) was found in 48% (lateral view), 53% (ventrodorsal view), and 64% (any view) of cats whereas left atrial enlargement was absent in 36% of cats in both views. Agreement between both methods of left atrial size estimation was poor (Cohen's kappa 0.17). Receiver operating characteristic curve analysis identified a maximum echocardiographic left atrial dimension of approximately 20 mm as the best compromise (Youden index) between sensitivity and specificity in the prediction of radiographic left atrial enlargement. Left atrial enlargement as assessed by thoracic radiography may be absent in a clinically relevant number of cats with congestive heart failure. Therefore, normal left atrial size on thoracic radiographs does not rule out presence of left-sided congestive heart failure in cats with clinical signs of respiratory distress.

Use of pimobendan in 170 cats (2006–2010)

Hypothesis/Objectives To describe the therapeutic use of pimobendan in cats, describe the patient population to which it was administered, document potential side effects and report the clinical course following administration of pimobendan in conjunction with standard heart failure therapy. It is hypothesized that cats with advanced heart disease including congestive heart failure from a variety of causes will tolerate pimobendan with a minimum of side effects when used in treatment in conjunction with a variety of other medications. Animals, materials and methods One hundred and seventy client owned cats with naturally occurring heart disease, one hundred and sixty four of which had congestive heart failure. Medical records were reviewed and owners and referring veterinarians were contacted for follow-up data. Data collected included pimobendan dose, other medications administered concurrently, data collected at physical examination, presence or absence of heart failure, adverse effects, classification of heart disease, echocardiographic data and survival time. The data were analyzed for significance between the initial visit and any follow-up visits. Results All cats were treated with pimobendan. The median pimobendan dose was 0.24 mg/kg q 12 h. Pimobendan was used in combination with multiple concurrent medications including angiotensin converting enzyme inhibitors, diuretics and anti-thrombotics. Five cats (3.0%) had potential side effects associated with pimobendan. One cat (0.6%) had presumed side effects severe enough to discontinue pimobendan use. Median survival time for 164 cats with congestive heart failure after initiation of pimobendan was 151 days (range 1–870). Conclusion Pimobendan appears to be well tolerated in cats with advanced heart disease when used with a variety of concurrent medications. Randomized controlled studies need to be performed to accurately assess whether it is efficacious for treatment of congestive heart failure in cats.