Effect of Body Weight on Echocardiographic Measurements in 19,866 Pure‐Bred Cats with or without Heart Disease

BackgroundStudies evaluating right ventricular (RV) structural and functional abnormalities in feline hypertrophic cardiomyopathy (HCM) are limited.HypothesisRight ventricular structural and functional abnormalities are present in cats with HCM and are associated with clinical severity.AnimalsEighty‐one client‐owned cats.MethodsRetrospective 2‐dimensional (2D) echocardiographic study. Right atrial diameter (RAD), RV free wall thickness (RVFWd), RV internal dimension (RVIDd), RV fractional area change (FAC), and tricuspid annular plane systolic excursion (TAPSE) were measured in control cats (n = 26), cats with subclinical HCM (subclinical HCM; n = 31), and cats with HCM and congestive heart failure (HCM + CHF; n = 24).ResultsRight heart size (RAD, RVFWd, and RVIDd) and RV function (FAC and TAPSE) significantly (all P < .05) increased and decreased, respectively, in the HCM + CHF group compared with controls. In the subclinical HCM group, only RVFWd was significantly (P < .05) higher than in controls. Compared with reference intervals derived from controls, 29% of cats with HCM had increased RVFWd. Increased left ventricular free wall thickness, increased RVIDd and decreased TAPSE independently correlated with increased left atrial size. Cats with HCM and pleural effusion were significantly more likely to have increased RVFWd and had increased RAD and decreased TAPSE compared with cats without pleural effusion.Conclusions and Clinical ImportanceRight ventricular remodeling and dysfunction occur in some cats with HCM and may be associated with clinical severity. Our results support involvement of RV in the pathophysiology of HCM in some cats and support echocardiographic assessment of the RV in cats with HCM.

Section: Discussioncontrasting

confidence: 67%

“…This finding is slightly less than that reported for dogs and the theoretical value used in the current study (0.33) when indexing RV free wall thickness to body weight. Given that echocardiographic variables in cats may scale differently,37 we acknowledge that this may affect the precision of our results for iRVFWd.…”

Section: Discussionmentioning

confidence: 98%

Echocardiographic Assessment of Right Ventricular Size and Function in Cats With Hypertrophic Cardiomyopathy

Visser

Sloan

Stern

2017

“…Two additional studies using ≥ 5.5 mm cut‐off reported 8.5% in 329 British shorthair cats in Denmark and 25% in 53 Norwegian Forest cats screened in London . Recently, echocardiographic reference ranges based on allometric scaling have been proposed …”

Section: Discussionmentioning

confidence: 99%

International collaborative study to assess cardiovascular risk and evaluate long‐term health in cats with preclinical hypertrophic cardiomyopathy and apparently healthy cats: The REVEAL Study

Fox

Keene

Lamb³

et al. 2018

175

BackgroundHypertrophic cardiomyopathy is the most prevalent heart disorder in cats and principal cause of cardiovascular morbidity and mortality. Yet, the impact of preclinical disease is unresolved.Hypothesis/ObjectivesObservational study to characterize cardiovascular morbidity and survival in cats with preclinical nonobstructive (HCM) and obstructive (HOCM) hypertrophic cardiomyopathy and in apparently healthy cats (AH).AnimalsOne thousand seven hundred and thirty client‐owned cats (430 preclinical HCM; 578 preclinical HOCM; 722 AH).MethodsRetrospective multicenter, longitudinal, cohort study. Cats from 21 countries were followed through medical record review and owner or referring veterinarian interviews. Data were analyzed to compare long‐term outcomes, incidence, and risk for congestive heart failure (CHF), arterial thromboembolism (ATE), and cardiovascular death.ResultsDuring the study period, CHF, ATE, or both occurred in 30.5% and cardiovascular death in 27.9% of 1008 HCM/HOCM cats. Risk assessed at 1, 5, and 10 years after study entry was 7.0%/3.5%, 19.9%/9.7%, and 23.9%/11.3% for CHF/ATE, and 6.7%, 22.8%, and 28.3% for cardiovascular death, respectively. There were no statistically significant differences between HOCM compared with HCM for cardiovascular morbidity or mortality, time from diagnosis to development of morbidity, or cardiovascular survival. Cats that developed cardiovascular morbidity had short survival (mean ± standard deviation, 1.3 ± 1.7 years). Overall, prolonged longevity was recorded in a minority of preclinical HCM/HOCM cats with 10% reaching 9‐15 years.Conclusions and Clinical ImportancePreclinical HCM/HOCM is a global health problem of cats that carries substantial risk for CHF, ATE, and cardiovascular death. This finding underscores the need to identify therapies and monitoring strategies that decrease morbidity and mortality.

“…One possible explanation for this finding is that heavier cats may exhibit more ventricular hypertrophy . In particular, body weight correlated with IVSd and LVPWd values in pure‐bred cats . Ventricular hypertrophy associated with body weight may increase the concentration of circulating cTnI.…”

Section: Discussionmentioning

confidence: 98%

Diagnostic utility of cardiac troponin I in cats with hypertrophic cardiomyopathy

Hori

Iguchi²,

Heishima

et al. 2018

BackgroundCardiac troponin I (cTnI) is useful for assessing hypertrophic cardiomyopathy (HCM) in cats.ObjectiveTo measure plasma cTnI concentrations in healthy cats and evaluate the clinical utility of cTnI in determining the severity of HCM.AnimalsClinically healthy cats (n = 88) and cats with HCM (n = 93).MethodsMulticenter prospective study. Cats with HCM, including hypertrophic obstructive cardiomyopathy at various stages, were diagnosed using echocardiography. Plasma cTnI concentrations were analyzed by a commercial laboratory. Receiver‐operating characteristic curve analysis was used to evaluate the accuracy of plasma cTnI concentrations to detect HCM.ResultsThe median cTnI concentration was 0.027 ng/mL (interquartile range, 0.012‐0.048 ng/mL) in healthy cats. Concentrations were significantly higher in diseased cats than in healthy controls, and concentrations were significantly higher in cats with heart failure than in asymptomatic cats. A plasma cTnI concentration of 0.163 ng/mL had a sensitivity of 62.0% and specificity of 100% when used to distinguish normal cats from asymptomatic HCM cats without left atrial dilatation. A cutoff of 0.234 ng/mL had high sensitivity (95.0%) and specificity (77.8%) for assessing heart failure. The areas under the receiver‐operating characteristic curves were 0.85 and 0.93, respectively.Conclusions and Clinical ImportanceIncreased cTnI concentrations reflect the severity of HCM. If other causes of cardiac injury are ruled out, plasma cTnI concentration may be useful for predicting the severity of HCM in cats.