Won-Kyoung Yoon

Comparison of 2 retrieval devices for heartworm removal in 52 dogs with heavy worm burden.

BACKGROUND For treating dogs with heavy heartworm infection, mechanical removal using various retrieval devices is useful. However, the efficacy and safety of retrieval devices have rarely been studied. HYPOTHESIS Catheter-based heartworm removal using 2 retrieval devices (basket and tripod grasping forceps) is efficient and safe for treating dogs with heavy worm burden. ANIMALS Fifty-two client-owned dogs with heavy (Class III and IV) worm burden. METHODS A retrospective study was performed on 52 dogs, using a catheter-based heartworm removal approach using 2 types of retrieval devices (ie, the basket and the tripod grasping forceps). The efficacy and complications associated with the 2 devices were assessed. RESULTS The basket device was used on 22 of the study group dogs, and the tripod grasping forceps was used on 30 of the dogs. The postoperative survival rate was 95.5% for the basket device and 80% for the tripod grasping forceps, but the difference was not statistically significant. The worm number captured per attempt was 3.5 ± 1.7 using the basket device and 1.9 ± 0.85 for the tripod grasping forceps (P < .05). Various complications associated with heartworm removal were noticed with both retrieval devices. CONCLUSIONS AND CLINICAL IMPORTANCE This study suggests that catheter-based heartworm removal is not only a relatively safe and efficient therapeutic method in dogs with heavy worm burden, but more efficient using the basket device. Our data do not indicate a clear safety advantage between the 2 devices evaluated, although the survival rate was numerically higher in dogs undergoing a basket intervention.

Assessment of Clinical Outcome in Dogs with Naturally Infected with Dirofilaria immitis after American Heartworm Society Protocol vs Slow Kill Method

Heartworm disease (HWD) in dogs is a life-threatening mosquito-borne disease resulting in right-sided congestive heart failure and inflammatory pulmonary disease. Due to complications from adulticidal therapy with melarsomine, slow kill protocol either with preventive dose of ivermectin or combined with doxycycline has been proposed for an alternative adultcidal therapy in dogs with HWD. Therefore, this study evaluated the clinical outcome of adultcidal therapy in dogs with class II stage of HWD after treating either American Heartworm Society (AHS) or slow kill protocol for 10 months. Clinical outcome after therapy was evaluated by clinical, radiographic and echocardiographic examination along with hematology before (D0) and after therapy (D300). Although clinical signs associated with HWD were all resolved after therapy in both groups, the infection was not cleared out 67% of dogs treated by slow kill protocol at the end of therapy. Furthermore, pulmonary arterial flow of acceleration time to ejection time ratio (AT/ET) and the right pulmonary artery distensibility index (RPADI) have been firstly used for detecting pulmonary hypertension in this study group. The pulmonary hypertension was more common in dogs with mild clinical signs, although tricuspid and pulmonary regurgitation were not detectable in most dogs in this study. Our study findings suggested that the slow kill protocol might not be efficacious enough to clear out HWD in dogs and more attention on the presence of pulmonary hypertension might be necessary for effective management of HWD in dogs.