Trypanosoma cruzi infection diagnosed in dogs in nonendemic areas and results from a survey suggest a need for increased Chagas disease awareness in North America.

Objective: To describe the clinical presentation and outcome in dogs diagnosed with Trypanosoma cruzi infection in nonendemic areas and to survey veterinary cardiologists in North America for Chagas disease awareness.

Animals: 12 client-owned dogs; 83 respondents from a veterinary cardiology listserv.

Procedures: A retrospective, multicenter medical records review to identify dogs diagnosed with American trypanosomiasis between December 2010 and December 2020.

Retrospective evaluation of hypertrophic cardiomyopathy in 68 dogs.

Background: There is a lack of clinical data on hypertrophic cardiomyopathy (HCM) in dogs.

Hypothesis/objectives: To investigate signalment, clinical signs, diagnostic findings, and survival in dogs with HCM.

Animals: Sixty-eight client-owned dogs.

Effects of pimobendan in cats with hypertrophic cardiomyopathy and recent congestive heart failure: Results of a prospective, double-blind, randomized, nonpivotal, exploratory field study.

Background: The benefits of pimobendan in the treatment of congestive heart failure (CHF) in cats with hypertrophic cardiomyopathy (HCM) have not been evaluated prospectively.

Hypothesis/objectives: To investigate the effects of pimobendan in cats with HCM and recent CHF and to identify possible endpoints for a pivotal study. We hypothesized that pimobendan would be well-tolerated and associated with improved outcome.

Effects of pimobendan on left atrial transport function in cats.

Background: Arterial thromboembolism is a sequela of hypertrophic cardiomyopathy (HCM) in cats related to left atrial (LA) enlargement and dysfunction.

Hypothesis: Pimobendan improves LA transport function in cats.

Animals: Twenty-two client-owned cats with HCM and 11 healthy cats.

Comparison of Two Commercially Available Immunoassays for the Measurement of Bovine Cardiac Troponin I in Cattle With Induced Myocardial Injury.

Multiple cardiac troponin I (cTnI) immunoassays are commercially available. Overall, assays have not been standardized, and inter-assay differences in the detection of the analyte cardiac troponin I can be clinically relevant. To compare the diagnostic accuracy of the commercially available Abbott i-STAT®1 cTnI immunoassay (i-STAT) and the previously validated ADVIA Centaur TnI-Ultra immunoassay (Centaur) in cattle.

Acquired left-to-right shunting through a valve-incompetent foramen ovale in a cat with hypertrophic cardiomyopathy and congestive heart failure.

Case Summary: An 8-year-old spayed female domestic shorthair cat was presented for a recheck evaluation of hypertrophic cardiomyopathy and chronic kidney disease. Three years prior to presentation, the patient was diagnosed with obstructive hypertrophic cardiomyopathy and started on atenolol. The left ventricular outflow tract obstruction subsequently resolved.

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

Background: Left-sided congestive heart failure (CHF) is characterized by increased filling pressures and related Doppler echocardiographic (DE) filling patterns.

Hypothesis: Doppler 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).

Animals: Forty-seven client-owned cats.

Cutting balloon and high-pressure balloon dilation for palliative treatment of congenital double-chambered right ventricle and primary infundibular stenosis in a Golden retriever dog.

Combined cutting balloon and high-pressure balloon dilation was performed in a dog with a double-chambered right ventricle and severe infundibular stenosis of the right ventricular outflow tract. The peak systolic pressure gradient across the stenosis decreased by 65% after dilation (from 187 mmHg before to 66 mmHg after) affirming the intervention as successful. However, early re-stenosis occurred within 3 months leading to exercise intolerance, exercise-induced syncope, and right-sided congestive heart failure.

The role of spatial organization of Ca release sites in the generation of arrhythmogenic diastolic Ca release in myocytes from failing hearts.

In heart failure (HF), dysregulated cardiac ryanodine receptors (RyR2) contribute to the generation of diastolic Ca waves (DCWs), thereby predisposing adrenergically stressed failing hearts to life-threatening arrhythmias. However, the specific cellular, subcellular, and molecular defects that account for cardiac arrhythmia in HF remain to be elucidated. Patch-clamp techniques and confocal Ca imaging were applied to study spatially defined Ca handling in ventricular myocytes isolated from normal (control) and failing canine hearts.

Echocardiographic evaluation of left ventricular diastolic function in cats: Hemodynamic determinants and pattern recognition.

Left ventricular (LV) diastolic dysfunction is highly prevalent in cats and is a functional hallmark of feline cardiomyopathy. The majority of cats with hypertrophic, restrictive, and dilated cardiomyopathy have echocardiographic evidence of abnormal LV filling, even during the occult (preclinical) phase. Moderate and severe diastolic dysfunction is an indicator of advanced myocardial disease, is associated with clinical signs including exercise intolerance and congestive heart failure, affects outcome, and influences therapeutic decisions.

Synchronous Diaphragmatic Flutter Secondary to Primary Hypoparathyroidism in a Dog.

A 3 yr old, spayed, female miniature mchnauzer was presented for rhythmic, spontaneous contractions of the abdominal wall and across the costal arches. The rate of contractions coincided with the heart rate and increased during exercise. The dog was diagnosed with primary hypoparathyroidism based on low plasma ionized calcium and serum parathyroid hormone (PTH) concentrations.

Iatrogenic embolization and transcatheter retrieval of a ventricular septal defect occluder in a dog.

A 7-month-old Irish Setter underwent transcatheter therapy of a muscular ventricular septal defect (VSD) and pulmonary valve stenosis. Standard devices for muscular VSD closure could not span the interventricular septum due to right ventricular hypertrophy, and an Amplatzer post-infarction muscular VSD occluder with a wider waist was successfully implanted. Following VSD closure, inflation of the balloon dilation catheter during balloon pulmonary valvuloplasty resulted in iatrogenic embolization of the VSD occluder to the left ventricular outflow tract.

Echocardiographic assessment of right ventricular systolic function in conscious healthy dogs following a single dose of pimobendan versus atenolol.

Objective: To quantify drug-induced changes in right ventricular (RV) systolic function after administration of pimobendan and atenolol.

Animals: 80 healthy privately-owned dogs.

Methods: Using a prospective, blinded, fully-crossed study design with randomized drug administration, RV systolic function was determined twice at two time periods; before and 3 h after administration of pimobendan (0.

Pulmonary artery dissection in eight dogs with patent ductus arteriosus.

Objectives: To describe a series of dogs with pulmonary artery dissection and patent ductus arteriosus (PDA).

Animals: Eight dogs.

Methods: Retrospective case series.

Echocardiographic assessment of right ventricular systolic function in conscious healthy dogs: repeatability and reference intervals.

Objectives: To determine the feasibility, repeatability, intra- and interobserver variability, and reference intervals for 5 echocardiographic indices of right ventricular (RV) systolic function: tricuspid annular plane systolic excursion (TAPSE), fractional area change (FAC), pulsed wave tissue Doppler imaging-derived systolic myocardial velocity of the lateral tricuspid annulus (S'), and speckle-tracking echocardiography-derived global longitudinal RV free wall strain and strain rate. To explore statistical relationships between RV systolic function and age, gender, heart rate, and bodyweight.

Animals: 80 healthy adult dogs.

Sudden death of a horse with supraventricular tachycardia following oral administration of flecainide acetate.

Objective: To describe a case of supraventricular tachycardia and sudden death in a horse following administration of flecainide acetate.

Case Summary: An 8-year-old Hanoverian warmblood gelding was treated for chronic, naturally occurring, supraventricular tachycardia with digoxin, procainamide hydrochloride, quinidine sulfate, and flecainide acetate. After oral administration of flecainide, polymorphic ventricular tachycardia (torsades de pointes) and ventricular fibrillation developed, leading to cardiovascular collapse and death.

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.

Effect of treatment with atenolol on 5-year survival in cats with preclinical (asymptomatic) hypertrophic cardiomyopathy.

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.

Single left coronary ostium and an anomalous prepulmonic right coronary artery in 2 dogs with congenital pulmonary valve stenosis.

A coronary artery anomaly characterized by the presence of a single left coronary ostium with absence of the right coronary ostium and an anomalous prepulmonic right coronary artery course was observed in two dogs with concurrent congenital pulmonary valve stenosis. This unique coronary artery anatomy is similar to the previously described single right coronary ostium with anomalous prepulmonic left coronary artery, the so-called type R2A anomaly, in that an anomalous coronary artery encircles the pulmonary valve annulus. Both dogs of this report, a boxer and an English bulldog, were of breeds known to be at risk for the type R2A anomaly.

Clinical evaluation of the 3M Littmann Electronic Stethoscope Model 3200 in 150 cats.

Detection of murmurs and gallops may help to identify cats with heart disease. However, auscultatory findings may be subject to clinically relevant observer variation. The objective of this study was to evaluate an electronic stethoscope (ES) in cats.

Effects of vagal maneuvers on heart rate and Doppler variables of left ventricular filling in healthy cats.

Background: Evaluation of left ventricular (LV) diastole is clinically important in cats with heart disease. Diastolic dysfunction is a main characteristic of feline cardiomyopathy and is associated with clinical signs and poor outcome. Numerous echocardiographic indices characterizing LV diastole exist, of which Doppler variables of transmitral flow and mitral annular motion are used most often.

Effects of treatment with ivabradine and atenolol on reproducibility of echocardiographic indices of left heart size and function in healthy cats.

Objectives: Data on reproducibility of echocardiographic indices in cats are commonly derived from studies in healthy, non-treated animals. However, medical treatment may alter reproducibility of such data possibly influencing interpretation of results of clinical trials assessing the effects of drugs on cardiovascular function. The objectives were therefore to investigate the effects of ivabradine and atenolol on reproducibility of echocardiographic indices of left heart function.

Effects of sedation on echocardiographic variables of left atrial and left ventricular function in healthy cats.

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.