Viktor Szatmári

The heart-to-single vertebra ratio measured at the seventh thoracic vertebra (HSVR-T7) is a recently described radiographic method used to assess heart size in dogs. Our study evaluated the diagnostic performance of HSVR-T7 for identifying echocardiographically defined cardiomegaly in dogs with myxomatous mitral valve disease (MMVD). Its correlation with vertebral heart score (VHS) and vertebral left atrial size (VLAS), and as its discriminatory performance compared with artificial intelligence (AI)-derived VHS and VLAS measurements were investigated. Radiographs of 93 dogs with echocardiographically confirmed myxomatous mitral valve disease were included; 35 were classified as ACVIM stage B1 and 58 as stage B2 or C. Among the 35 stage B1 dogs, five (14.3%) had isolated left atrial enlargement and two (5.7%) had isolated left ventricular enlargement. The HSVR-T7 scores were significantly higher in dogs with echocardiographically confirmed cardiomegaly (stage B2 or C) than in dogs without cardiomegaly (stage B1): 11.65 ± 1.13 versus 10.47 ± 1.08 (p < 0.001). At the optimal cut-off value of ≥11.15, HSVR-T7 yielded an area under the curve (AUC) of 0.769 of the receiver operating characteristic (ROC) curve, with 70.7% sensitivity and 74.3% specificity. The HSVR-T7 showed a very strong positive correlation with VHS (r = 0.890; p < 0.001). Artificial intelligence-derived VHS showed the highest diagnostic performance at an optimal cut-off value of ≥11.35 (AUC, 0.861; sensitivity, 75.9%; specificity, 82.9%), whereas AI-derived VLAS yielded an AUC of 0.765, with 62.1% sensitivity and 85.7% specificity at an optimal cut-off value of ≥2.65. Overall, HSVR-T7 was less sensitive and specific in detecting cardiomegaly in dogs with myxomatous mitral valve disease than VHS, and it cannot replace echocardiographic, VHS or VLAS measurements.

Balloon valvuloplasty is a commonly performed catheter-based procedure in dogs with congenital pulmonic stenosis. Worldwide, veterinary cardiologists often administer peri- and postoperative prophylactic antimicrobials to prevent infectious complications, like bacterial endocarditis. Infective endocarditis of the pulmonary valve is, however, extremely rare in dogs, and it has never been reported after balloon valvuloplasty. The objective of this retrospective case series was to investigate the incidence of infective endocarditis, if balloon dilatation of pulmonic stenosis was performed without antimicrobial prophylaxis. Medical records of dogs operated at a university teaching hospital in a 20-year period from 2006 to 2025 were reviewed for clinical signs and echocardiographic changes that could be caused by infective endocarditis. Of the 83 dogs that were operated without peri- or postoperative antimicrobial prophylaxis, survived the surgery, and had at least three weeks of follow-up, none developed infective endocarditis. Follow-up in 68 dogs was based on medical history, physical examination and echocardiography during rechecks at the authors’ institution. Follow-up information from the remaining 15 dogs was gained from the owners and/or the referring veterinarians. Our study demonstrated zero event rate in dogs that underwent balloon dilatation of congenital pulmonic stenosis without antimicrobial prophylaxis.

Hyperthyroidism is a common endocrine disorder in elderly cats, often leading to concurrent cardiac abnormalities. Understanding the development of these cardiac abnormalities and the effect of treatment is crucial for optimizing monitoring strategies and long-term management. Hyperthyroid cats frequently develop cardiomegaly, with left ventricular concentric and/or eccentric hypertrophy, and left atrial dilation. Cardiac abnormalities described in humans with multinodular toxic goiter may differ from those in cats, but, as in humans, these abnormalities are often reversible once thyroid hormone levels are normalized. Definitive treatment options for hyperthyroidism, such as radioiodine therapy and thyroidectomy, are the most successful at restoring the normal thyroid hormone levels. Medical therapy and iodine-restricted diets can also help normalize thyroid hormone levels, thereby aiding the reversal of cardiac abnormalities. However, cats with pre-existing cardiac diseases, like hypertrophic cardiomyopathy, may not show reversible cardiac changes due to these concurrent primary cardiac diseases. Cats with hyperthyroidism should routinely undergo echocardiographic evaluations to monitor for concurrent cardiac abnormalities, both before and after treatment. More importantly, every cat older than 6 years of age with echocardiographic or clinical signs of heart disease should be screened for hyperthyroidism. With appropriate treatment of hyperthyroidism, heart failure can be prevented.

Left-sided congestive heart failure (CHF) is a common cause of acute respiratory distress in cats, and echocardiographic assessment of left atrial (LA) size is an important test to differentiate it from respiratory diseases that cause similar clinical signs. Furosemide, a potent loop diuretic, is the first-line therapy for cardiogenic pulmonary edema, but its effect on LA size has not been systematically investigated in cats. Some dyspneic cats are referred after having received high doses of furosemide by the referring veterinarian without prior point-of-care ultrasound (POCUS). This can make the diagnosis of CHF challenging. If furosemide significantly reduces left atrial size, it could potentially lead to misdiagnosis, by erroneously categorizing these cats as not having CHF. This prospective, observational multicenter study enrolled 25 cats with acute left-sided CHF. Point-of-care ultrasound was used to assess LA to aortic ratio (LA:Ao) and maximal LA diameter (LAD) at admission and three hours after furosemide administration. Significant reductions were observed in LA:Ao (2.48 ± 0.35 to 2.17 ± 0.40; p < 0.001), LAD (21.0 ± 2.8 mm to 18.4 ± 3.2 mm; p < 0.001), and respiratory rate (64 ± 30 to 40 ± 14 breaths/min; p < 0.001). Normalization of respiratory rate occurred in 50% of cats, while normalization of maximum LAD occurred in 32%. One cat achieved normalization of LA:Ao. We found that furosemide induced rapid reduction in LA size and respiratory rate in cats with left-sided CHF. Clinicians should be aware that severe LA dilation can be absent in referred dyspneic cats that had already received furosemide.

Background: Some dogs with severe mitral valve regurgitation can have chronic cough, but its cause is unclear. Many of these dogs exhibit left principal (synonym mainstem) bronchial collapse or compression. Some clinicians believe that an enlarged heart, particularly the dilated left atrium, compresses the left principal bronchus, while others argue that a healthy bronchus cannot be compressed and that the cough is due to concurrent airway disease, such as bronchomalacia. In this study, we aimed to investigate the correlation between chronic cough and radiographic signs of bronchial narrowing in dogs with cardiomegaly secondary to primary mitral valve regurgitation. Methods: Four radiologists independently evaluated 51 sets of thoracic radiographs from client-owned dogs with cardiomegaly due to severe mitral valve regurgitation, including 26 sets of radiographs belonging to dogs with chronic (>8 weeks) cough and 25 without cough. The presence or absence of bronchial narrowing was assessed while the radiologists were blinded to patient characteristics and each other’s findings. Results: Interobserver variability was high, and the radiologists could not reliably predict which dogs had a chronic cough. Dogs with left atrial enlargement and airway narrowing sometimes coughed and sometimes did not. Likewise, some dogs with left atrial enlargement but no signs of airway compression or collapse coughed, and some did not. It was impossible to distinguish the groups based on these features. Conclusions: Bronchial compression by an enlarged heart and left atrium is an unlikely cause of chronic cough in dogs with severe primary mitral valve regurgitation.

A 1-year-old Maltese–Poodle mixed breed dog was referred to the cardiology service because of severe exercise intolerance and daily exercise-induced syncopal episodes. Physical examination revealed no abnormalities. Echocardiography showed intermittent underfilling of the heart. Abdominal ultrasound examination revealed a segmental aplasia of the caudal vena cava between the kidneys and the liver, and azygos continuation of the cava. The azygos vein dorsal to the right kidney showed a severe aneurysm with stasis of blood. Computed tomographic angiography showed that the right crus of the diaphragm was probably responsible for the intermittent compression of the dilated azygos vein, which was thought to have subsequently led to insufficient venous return to the heart. The underfilled ventricles could not produce sufficient cardiac output, which caused the assumed cerebral hypoperfusion due to presumed systemic arterial hypotension. Under general anesthesia a self-expanding nitinol stent was implanted into the azygos vein at the level of the diaphragm. All clinical signs resolved immediately after surgery. The dog remained free from clinical signs (6 months after surgery). This is the first report that describes the successful treatment of this congenital vascular anomaly. Ultrasonography of the caudal vena cava should be performed in dogs with unexplained syncope.

Background: Purring in cats can interfere with cardiac auscultation. If the produced noise is loud enough, purring makes it impossible to perform a meaningful auscultation as it is much louder than heart sounds and murmurs. Our study introduced and tested a new, simple, fear-free, cat-friendly method to stop purring during auscultation. Methods: The technique involves grasping the cat’s larynx from ventral with one hand, while simultaneously holding the stethoscope in the other hand to perform the auscultation. Results: The incidence of purring was evaluated in 582 cats, in a veterinary teaching hospital and in a cat-friendly private practice. Fifty-one (8.8%) cats were purring during their physical examination. The tested method had a success rate of 89% in terminating purring. A comparison between investigators (a veterinary student versus an experienced veterinary cardiology specialist) showed no significant difference in the effectiveness of the method (p = 0.57). The incidence of purring was not significantly different between the teaching hospital and the cat-friendly practice (p = 1.00). Sick and older cats purred more often than healthy and younger cats. Conclusions: This new, simple, easy-to-master method is an improvement over previously reported techniques and supports the need for stress-free, cat-friendly handling in veterinary practice.

Background: Heart murmurs in puppies can be innocent or pathologic; the latter is almost always related to a congenital heart disease. Differentiating between these murmurs can be challenging for practicing veterinarians, but this differentiation is essential to ensure the best prognosis for puppies having a congenital heart disease. Our study aimed to reveal how veterinarians manage puppies with a heart murmur. Methods: A web-based questionnaire was sent to Dutch and Belgian veterinary practices. Results: Data from 452 respondents were analyzed. Though 88% of the respondents find detecting a heart murmur easy, only 9% find differentiating innocent murmurs from pathologic murmurs in puppies easy. Of the respondents, only 80% recommend immediate additional examination when detecting a loud heart murmur during the first veterinary health check at 6 weeks of age. Most of the respondents are aware that normal growth and the absence of clinical signs do not exclude severe congenital heart disease. Of the respondents, 31% were uncertain whether early surgical intervention could lead to improved outcomes. Conclusions: Veterinarians are aware of the importance of echocardiography for puppies with a loud heart murmur, and recognize their limitations when differentiating an innocent from a pathological heart murmur in a puppy.