Outcomes of dogs with recurrent idiopathic pericardial effusion treated with a 3-port right-sided thoracoscopic subtotal pericardiectomy

Intercostal thoracoscopic pericardiectomy in left lateral recumbency: A cadaveric study of feasibility, efficiency, and extent of pericardial resection

OBJECTIVE

To describe the feasibility, efficiency, and extent of thoracoscopic pericardiectomy (TP) on a ventilated dog with an intercostal approach in lateral recumbency (ILR), in comparison with the traditional transdiaphragmatic paraxiphoid approach in dorsal recumbency (PDR).

STUDY DESIGN

Randomized experimental study.

ANIMALS

Twenty canine cadavers (n = 10 per group).

METHODS

Thoracoscopic pericardiectomy was performed on mechanically ventilated cadavers to remove the largest pericardial fragment possible using either the ILR or PDR technique. Approach and procedure time were recorded, and surgical extent (cardiac exposure/exteriorization, pericardial fragment area) was assessed. Procedural difficulty and intraoperative visibility were also assessed to evaluate feasibility.

RESULTS

Total surgical time (sum of approach and pericardiectomy time) did not differ between groups, although PDR pericardiectomy took longer (p = .045) by an average of 5.2 min. Exteriorization of the heart from the pericardial sac was achieved for all trials. Pericardial fragments from PDR trials were larger than those of ILR (p = .004), with a mean difference of 23.21 cm2. Cardiac exposure and operative visibility scores were greater for PDR procedures.

CONCLUSION

The ILR approach with bilateral ventilation was a feasible alternative for performing partial pericardiectomies, which did not require more total surgical time when compared with the PDR approach.

CLINICAL SIGNIFICANCE

The ILR approach for TP warrants further evaluation in live dogs as it may hold promise for treating causes of pericardial effusion that do not require subtotal pericardiectomy and improving efficiency when paired with other ILR procedures such as thoracic duct ligation.

Outcome of dogs treated with chemotherapy for mesothelioma: A retrospective clinical study on 40 cases and a literature review

Mesothelioma is an uncommon cancer in dogs for which there is no established standard of care. Chemotherapy is often suggested despite no definitive proof of efficacy. The aim of this study was to evaluate the impact of chemotherapy on survival of dogs with mesothelioma. A retrospective multicentric study was carried out. To be included, dogs needed to present an evocative clinical evolution and a morphological diagnosis of mesothelioma. Exclusion of other cause of effusion and complete clinical follow-up were also required. Fourty dogs were included, 27 received chemotherapy (group 1) and 13 did not (group 2). Groups were heterogeneous regarding the proportion of animals undergoing surgery as part of their treatment (16 in group 1, 2 in group 2; p = .016) and homogeneous otherwise. Univariate analysis showed that dogs from group 1 survived significantly longer than dogs from group 2 (MST: 366 vs. 74 days; p < .001). Complete resolution of effusion after the first chemotherapy administration positively correlated with survival in group 1 (MST: 415 vs. 160 days; p < .01). All other variable tested had no significant impact on survival in univariate analysis, but dogs undergoing surgery and dogs having serous membranes' modification at medical imaging tended to survive longer. Multivariate analysis confirmed that chemotherapy was the sole variable independently associated with survival in our study (odds ratio 5.57-6.12; p < .01).

Evaluation of Thoracoscopic Pericardial Window Size and Execution Time in Dogs: Comparison of Two Surgical Approaches

Pericardial effusion presents clinicians with a challenge when diagnosing the underlying cause and performing a prognosis. Different techniques have been suggested for canine thoracoscopic pericardiectomy with the creation of variable pericardial window size. The aim of this study was to statistically compare the surgical time and achieved window size of the paraxiphoid transdiaphragmatic and monolateral intercostal approaches. The paraxifoid and monolateral intercostal approaches showed a mean surgical time of 55 ± 20.08 (SD) minutes and 13.94 ± 4.61 (SD) minutes, and a mean pericardial window diameter of 4.23 ± 0.80 (SD) cm and 3.31 ± 0.43 (SD) cm, respectively. A significant correlation was observed between the dogs' bodyweight and window size (r = 0.48; p = 0.04) for both surgical approaches, and between the dogs' bodyweight and surgical time (r = 0.72; p = 0.0016) for monolateral intercostal approach. All treated dogs showed no clinical signs of recurrent cardiac tamponade during the follow-up. Our results provided useful information to help surgeons make the definitive choice of the surgical technique to treat the pericardial effusion.