Reversible right-sided congestive heart failure secondary to primary hyperaldosteronism in a cat.

A 10-year-old male castrated Somali cat presented with neurologic signs, severe systemic hypertension, and hypokalemia. Abdominal ultrasonography demonstrated a left adrenal mass, and the serum aldosterone concentration was increased. Computed tomography and follow-up diagnostic testing confirmed a left adrenal mass consistent with functional adenocarcinoma; additional findings included chronic airway and parenchymal disease. Transthoracic echocardiography revealed biatrial enlargement, with abdominal and pericardial effusion, consistent with right-sided congestive heart failure. The cat was treated for congestive heart failure and adrenalectomy was performed. Cardiac structure and function returned to normal within 6 months postoperatively. This report highlights a case of reversible congestive heart failure secondary to primary hyperaldosteronism.

Candida tropicalis infectious endocarditis in a dog with a patent ductus arteriosus.

A 6-month-old male intact miniature Australian Shepherd presented for surgical consultation for a previously diagnosed patent ductus arteriosus. Echocardiogram revealed a patent ductus arteriosus and a hyperechoic oscillating lesion within the main pulmonary artery. Blood cultures and eventual post-mortem examination revealed Candida tropicalis endocarditis. This case report highlights a rare case of fungal endocarditis with both echocardiographic and post-mortem findings.

The utility of cardiac-gated computed tomography in diagnosing a reverse patent ductus arteriosus in a dog with a concurrent intracardiac right-to-left shunt.

A five-month-old male intact Goldendoodle presented for evaluation for peripheral cyanosis following exercise. Transthoracic echocardiography demonstrated severe right ventricular wall thickening and right atrial dilation secondary to pulmonary hypertension. An agitated saline contrast study demonstrated an interatrial right-to-left shunt. Cardiac-gated computed tomography confirmed a reverse patent ductus arteriosus. This case report highlights the utility of cardiac-gated computed tomography in identifying multi-level intra- and extra-cardiac shunts.

Transient P' waves in a hyperkalemic cat: artifact or dissociation?

A 15-year-old Sphynx cat was referred for cervical ventroflexion, ataxia, and lethargy associated with hypokalemia. After administration of supplemental potassium, the cat became severely hyperkalemic. Transient P' (vs. pseudo P' waves) were detected on the electrocardiogram. Over the course of hospitalization, the cat's potassium normalized, and the abnormal P' waves did not recur. These images are presented to highlight the differential diagnoses for this type of electrocardiogram. Diagnostic considerations included complete or transient atrial dissociation (as a rare consequence of hyperkalemia), atrial parasystole, and various electrocardiographic artifacts. Definitive diagnosis of atrial dissociation requires an electrophysiologic study or echocardiographic documentation of two independent atrial rhythms with associated mechanical activity, but these were unavailable in this case.

The utility of point-of-care ultrasound right-sided cardiac markers as a screening test for moderate to severe pulmonary hypertension in dogs.

Dogs with respiratory disease can develop pulmonary hypertension (PH), a comorbid condition that can impact therapy and prognosis. Without confirmation using the criterion standard of echocardiography, this complication may be missed. Point-of-care ultrasound (POCUS) is a simple, non-invasive screening test that may suggest PH. It was hypothesized that in dogs POCUS right-sided cardiac markers (R-SCM) at the subxiphoid view would predict moderate to severe PH confirmed by echocardiography. Forty-three client-owned dogs that underwent respiratory evaluation with POCUS and echocardiography were included. POCUS R-SCM evaluated in the subxiphoid view included subjective caudal vena cava distention (CVCsx), CVCsx >1cm, gallbladder wall edema and ascites. PH was defined by tricuspid regurgitation pressure gradient (TRPG) as mild (30-49.9mmHg), moderate (50-74.9mmHg) or severe (>75mmHg). POCUS subxiphoid views were blindly evaluated post hoc and compared to echocardiography. Chi square test and one-way ANOVA were used to evaluate correlations between POCUS R-SCM and echocardiographic diagnosis of moderate to severe PH. Twenty-six dogs with PH, and 17 dogs without PH, were enrolled. There was no significant difference in the presence or absence of any R-SCM between dogs with and without PH. When dogs with no PH and mild PH were grouped and compared to dogs with moderate to severe PH (i.e., dogs for which treatment for PH would be recommended), no significant differences in R-SCM were noted. POCUS R-SCM using the CVCsx view was not a sensitive screening test to identify dogs with PH in this study population.

Clinical efficacy of tadalafil compared to sildenafil in treatment of moderate to severe canine pulmonary hypertension: a pilot study.

INTRODUCTION: Canine pulmonary hypertension (PH) is associated with high morbidity and mortality. Tadalafil, a phosphodiesterase-5 inhibitor used commonly in humans with PH, has not been evaluated in a clinical trial in dogs with naturally occurring PH. Our objectives were to compare the efficacy of tadalafil and sildenafil on PH assessed by peak tricuspid regurgitant flow velocity, estimated systolic pulmonary arterial pressure gradient, voluntary activity, quality of life, and safety profiles in dogs with moderate to severe PH. ANIMALS: Twenty-three dogs with echocardiographic evidence of moderate to severe PH were enrolled. METHODS: A prospective short-term, randomized, double-blinded pilot study was carried out. Dogs with PH were randomly allocated to receive sildenafil or tadalafil for 2 weeks and assessed via echocardiography, activity monitors, and owner-reported outcomes. RESULTS: Collectively, phosphodiesterase-5 inhibition significantly decreased (improved) quality of life scores (p = 0.003) and visual analog score (p = 0.024) without significant between-treatment difference of these variables. Phosphodiesterase-5 inhibition did not significantly affect peak tricuspid regurgitant flow velocity (p = 0.056) or voluntary activity (p = 0.27). A total of 33% (7/21) of dogs experienced at least one adverse event during the study (tadalafil, n = 5; sildenafil, n = 2) with no significant difference between treatment type and incidence of adverse events (p = 0.36). DISCUSSION: In this pilot study, phosphodiesterase-5 inhibition led to apparent improvement in quality of life scores without documenting superiority of tadalafil over sildenafil. CONCLUSION: Tadalafil at a dose of 2 mg/kg once daily appears to be a viable alternative to sildenafil in dogs with moderate to severe PH.