Peer-reviewed veterinary case report
Non-invasive fluid assessment in dogs with patent ductus arteriosus
By Li, Zongru et al.·Published in Veterinary Sciences·2025·Department of Veterinary Surgery, Faculty of Veterinary Medicine, Tokyo University of Agriculture and Technology, Fuchu 183-8509, Japan, Japan·View original on Crossref →
PetCaseFinder translated the abstract of this peer-reviewed paper into plain English so pet owners can read it. We do not publish original research — every detail traces back to the citation above. How we work →
Original publication title: The Role of Phase Angle in Non-Invasive Fluid Assessment in Dogs with Patent Ductus Arteriosus: A Novel Method in Veterinary Cardiology
- Species:
- dog
Plain-English summary
A group of dogs with patent ductus arteriosus (PDA), a heart condition that can lead to fluid buildup and heart failure, were studied to see if a new non-invasive test called phase angle (PhA) could help assess their fluid levels. The researchers found that dogs with PDA had lower PhA readings, which correlated with other heart measurements. After surgery to correct the PDA, the dogs showed improvement in their PhA levels, indicating that this test could be useful for monitoring heart health and fluid balance in these dogs.
People also search for: dog heart condition PDA treatment · non-invasive fluid assessment in dogs · phase angle test for dogs
Abstract
Background: Patent ductus arteriosus (PDA) in dogs causes persistent left-to-right shunting, leading to pulmonary overcirculation, left heart volume overload, and potential congestive heart failure. Accurate assessment of fluid imbalance is essential but challenging with conventional echocardiography or biomarkers. Phase angle (PhA), derived from bioelectrical impedance analysis (BIA), may serve as a non-invasive marker of extracellular fluid distribution and cellular integrity. Objectives: This study aimed to evaluate PhA as an indicator of thoracic fluid imbalance in dogs with PDAby analyzing its correlation with pulmonary velocity (PV) and end-diastolic volume (eV), as well as its responsiveness to surgical correction. In addition, we assessed the relationships between PhA and echocardiographic structural indices (LA/Ao, TDI Sep E/Em, TDI Lat E/Em) and examined the influence of the measurement region. Methods: PhA was measured at 5, 50, and 250 kHz in 30 PDA-affected and 15 healthy dogs, with electrode placement across thorax, trunk, and abdomen. Echocardiography evaluated PV, eV, and PDA-specific structural parameters. Results: Thoracic PhA at 5 kHz was significantly reduced in PDAdogs, strongly correlated with PV and moderately with eV. Postoperative measurements showed progressive PhA recovery. Only TDI Lat E/Em correlated with mid-frequency PhA, while other structural indices showed minimal association. Thoracic PhA was lower than trunk or abdominal values, indicating that thoracic measurements may better capture localized extracellular fluid changes in PDAcompared with other regions. Conclusion: Thoracic PhA at 5 kHz effectively reflects extracellular fluid changes in PDA, complements structural echocardiography, and tracks postoperative fluid normalization. Its non-invasive nature supports clinical utility for monitoring hemodynamic burden and therapeutic response.
Find similar cases for your pet
PetCaseFinder finds other peer-reviewed reports of pets with the same symptoms, plus a plain-English summary of what was tried across them.
Search related cases →Original publication on Crossref: https://doi.org/10.3390/vetsci12101007