Comparison of two-dimensional imaging to three-dimensional modeling of intrahepatic portosystemic shunts using computed tomography angiography.

Computed tomography angiography (CTA) is used for the diagnosis of intrahepatic portosystemic shunts (IHPSS). When planning for transcatheter intervention, caudal vena cava (CVC) measurements are typically obtained from two-dimensional (2D) imaging to aid in stent selection. We hypothesized that clinically applicable three-dimensional (3D) IHPSS models can be generated, and CVC measurements will not differ between 2D images and 3D models. Computed tomography angiography datasets from client-owned dogs with IHPSS at the University of Georgia Veterinary Teaching Hospital from 2016 to 2022 were analyzed. Materialise Mimics 25.0 and 3-matic 17.0 were used for 3D modeling. Caudal vena cava diameters were measured in 2D dorsal and transverse planes 20 mm cranial and caudal from the shunt ostium and were compared with CVC diameters from 3D models. Length was measured in the 2D dorsal plane between midpoints of each diameter and compared to the 3D model length. Data are presented as mean (SD), and intraclass correlation coefficients were performed. Three-dimensional models were generated for 32 IHPSS (15 right-, 12 left-, and five central-divisional). Two-dimensional dorsal and transverse area-associated diameter measurements were 16.7 mm (5.6) and 15.5 mm (4.2) cranial; 14.9 mm (4.2) and 14.3 mm (3.7) caudal. Three-dimensional area-associated diameter measurements were 15.3 mm (4.4) cranial and 14.0 mm (3.6) caudal. The 2D length was 61.5 mm (7.1) compared with 3D 59.9 mm (7.2). Intraclass correlation coefficients comparing 2D and 3D diameters were all >0.80, indicating very good agreement, with good agreement (>0.60) for length. Clinically applicable 3D IHPSS models can be generated using engineering software. Measurements from 3D models are consistent with 2D planar imaging. Both 2D CTA and 3D virtual models can be utilized for preprocedural planning, depending on clinician preference.

Mitral Valve Repair-The Development and Rise of Options in the Veterinary World.

Both open surgical repair and a hybrid-interventional option are now available for mitral valve repair (MVR) at select veterinary centers worldwide, making the need for awareness of options and the intricacies around case selection of increasing importance. This article will overview both options currently available and their current stages of progress.

A multicenter, retrospective study of cardiac disease in Borzoi dogs.

Borzoi are large, relatively uncommon sighthounds anecdotally reported to suffer from sudden death. This multicenter retrospective cohort study aimed to describe the sample of Borzoi presenting to veterinary cardiologists for evaluation, with records searched from 14 centers across a study period of up to 20 years. The study sample was comprised of 152 client-owned Borzoi, with dogs most commonly presenting for pre-breed screening in 87/152 (52%), followed by evaluation of an arrhythmia in 28/152 (18%). Of the 131/152 (86%) dogs that had an echocardiogram performed, 85/131 (65%) were structurally normal, with 40/85 (47%) structurally normal dogs having trace or mild atrioventricular valve regurgitation. Tricuspid valve dysplasia was the most commonly diagnosed congenital cardiac disease (n = 6). Myxomatous mitral valve disease (n = 12) and dilated cardiomyopathy (n = 13) were diagnosed at similar frequencies, though 92% of valve disease cases were mild. Only 48/152 (32%) Borzoi had a diagnostic electrocardiogram (ECG) and/or a Holter monitor for arrhythmia screening. Despite this, ventricular arrhythmias were identified during the entirety of the available cardiac evaluation including diagnostic ECG, contemporaneous ECG monitoring during the echocardiogram, and/or Holter monitor in 25/131 (19%) dogs in which an echocardiographic diagnosis was available. Of these 25 Borzoi, 76% had minimal or no structural cardiac disease identified, and five had a family history of sudden death. A sudden death outcome was reported in 3/55 (5%) Borzoi with long-term outcome data available. In conclusion, Borzoi commonly have trace or mild atrioventricular valve insufficiencies, and may develop ventricular arrhythmias and dilated cardiomyopathy.

Effect of calibration methods on the accuracy of angiographic measurements during transcatheter procedures in dogs.

BACKGROUND: Different methods to perform reference calibration of an angiographic image exist; however, a prospective comparison of calibration methods has yet to be investigated in veterinary medicine. OBJECTIVE: To compare angiographic measurements using two commonly employed reference calibration methods, an esophageal pigtail marker catheter (EC) versus a radiopaque table ruler (TR). ANIMALS: Thirty-five client-owned dogs undergoing transcatheter intervention. METHODS: Prospective comparison study. Two reference calibration methods, EC and TR, were recorded in dogs undergoing transcatheter procedures from May 2016 to July 2017. Relevant measurements were performed in triplicate and averaged after image calibration to either EC or TR. Comparisons between methods were made by correlation, paired t-test, the method of Bland and Altman, and Passing-Bablok regression. RESULTS: A total of 39 angiographic structures were measured. Interventions included balloon pulmonary valvuloplasty (n = 21), patent ductus arteriosus occlusion (n = 11), subaortic or sub-pulmonary balloon dilatation (n = 4), and cor triatriatum membranostomy (n = 3). Angiographic measurements were larger when calibrated to EC versus TR (P < .0001). The mean bias was 0.86 mm, with greater bias for larger measurements. The EC measurements were ∼10% greater than TR based on regression analysis. Weight was correlated to the difference between methods (ρ = 0.55, P = .0003). CONCLUSIONS AND CLINICAL IMPORTANCE: Angiographic image calibration using a ruler placed on the fluoroscopy table underestimates the size of a structure by ∼10% as compared with a marker catheter placed within the esophagus. This effect is greatest when measuring larger structures such as the pulmonary valve annulus and in larger dogs.

Role of computed tomography angiography in the differentiation of feline truncus arteriosus communis from pulmonary atresia with ventricular septal defect.

Two domestic shorthair cats, a 6-month-old castrated male and a 7-month-old intact female, were diagnosed with complex congenital heart disease. Transthoracic echocardiography in both cats revealed a dilated arterial trunk overriding the interventricular septum with a large ventricular septal defect. The pulmonary trunk and branch pulmonary arteries were not visible using standard echocardiographic views in either cat. The differential diagnosis for both cats included truncus arteriosus communis vs. pulmonary atresia with ventricular septal defect. Each cat underwent computed tomography angiography to determine the origin and extent of the pulmonary blood supply and to better define extra-cardiac anatomy. Computed tomography angiography led to a diagnosis of truncus arteriosus communis with unrestricted pulmonary blood flow in one cat, whereas the other cat was diagnosed with pulmonary atresia with ventricular septal defect and major aortopulmonary collaterals serving as the primary source of pulmonary blood flow. Computed tomography angiography allowed for the ante mortem differentiation of truncus arteriosus communis from pulmonary atresia with ventricular septal defect in these two cats, leading to an accurate diagnosis and providing valuable information to therapeutic decision-making for each case.

Advanced multimodality imaging of an anomalous vessel between the ascending aorta and main pulmonary artery in a dog.

A 1-year-old male German shorthaired pointer was referred for evaluation of tachypnea and hemoptysis. A grade VI/VI left basilar continuous murmur was ausculted. Multimodality imaging consisting of thoracic radiographs, transthoracic and transesophageal echocardiography, fluoroscopy-guided selective angiography, computed tomography angiogram (CTA) and magnetic resonance angiogram (MRA), was performed on this patient. The defect included a left-to-right shunting anomalous vessel between the ascending aorta and main pulmonary artery, along with a dissecting aneurysm of the main and right pulmonary artery. An MRA post-processing technique (PC VIPR) was used to allow for high resolution angiographic images and further assessment of the patient's hemodynamics prior to surgical correction. This case report describes the clinical course of a canine patient with a rare form of congenital cardiac disease, and the multiple imaging modalities that were used to aid in diagnosis and treatment.