Peer-reviewed veterinary case report
QT apex changes in dogs with cancer treated with doxorubicin
By Kitagawa, Keita et al.·Published in Journal of veterinary internal medicine·2025·Department of Small Animal Clinical Sciences, United States·View original on PubMed →
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 We do not publish original research — every detail traces back to the citation above.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: Longitudinal Assessment of QT Apex in Tumor-Bearing Dogs Receiving Doxorubicin Monotherapy.
- Species:
- dog
Plain-English summary
A group of 45 dogs with cancer received a chemotherapy drug called doxorubicin (DOX) to treat their tumors. Researchers monitored their heart activity through ECGs to check for any changes in a specific heart measurement called QT apex (QTa), which can indicate heart problems. After analyzing the data, they found that even after multiple doses of DOX, there were no significant changes in the QTa, suggesting that this treatment did not negatively affect the dogs' heart function in this regard.
People also search for: dog cancer treatment doxorubicin · dog heart problems chemotherapy · doxorubicin side effects in dogs
Abstract
BACKGROUND: The cardiac morphologic and functional derangements induced by doxorubicin (DOX) are referred to as DOX-induced cardiotoxicity (DOX-IC). Prolongation of the QT apex (QTa) has been identified as a potential marker for the early detection of DOX-IC in humans. OBJECTIVES: Describe changes in QTa that occur in dogs with cancer undergoing DOX monotherapy. ANIMALS: Forty-five client-owned dogs. METHODS: Descriptive analysis of data routinely recorded as part of case management of dogs with cancer. Dogs included in the study had a confirmed malignant neoplasm, received DOX as a monotherapy, and had at least 4 ECGs > 30 s. All ECGs included in the study were recorded before DOX administration. Five heartbeats with a stable signal and minimal artifact were randomly selected from each dog, and the QTa was blindly evaluated in lead II, lead III, or both. Subsequently, a linear mixed model was used to quantify the effect of a cumulative dose of DOX on the QTa interval, adjusting for the effect of the other clinical variables. RESULTS: Forty-five dogs met the inclusion criteria. Among them, 39/45 received five DOX treatments and 26/45 received six DOX treatments. For ECG analysis, 234 ECGs were evaluated for changes in the QTa. The average cumulative dose of DOX was 154.1 mg/m. There was no significant impact of the DOX treatments on the change in QTa (p = 0.8). CONCLUSIONS: Administration of DOX up to a cumulative dose of 154.1 mg/mdoes not result in QTa prolongation.
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 PubMed: https://pubmed.ncbi.nlm.nih.gov/40574490/