A survey on dogs with valvular disease flying to Japan for operation.

In small-breed dogs, myxomatous mitral valve disease (MMVD) is a common disease which may lead to chronic heart failure. Mitral valve repair is an optimal surgical treatment that is currently available in limited veterinary facilities globally because it requires a special surgery team and specific devices. Therefore, some dogs must travel overseas to undergo this surgery. However, a question arises regarding the safety of dogs when traveling by air with a heart disease. We aimed to evaluate the effect of flight journey on dogs with mitral valve disease, including survival rates, symptoms during the trip, laboratory test results, and operational outcomes. All dogs stayed near the owner in the cabin during the flight. The survival rate after the flight was 97.5% in 80 dogs. The surgical survival rates (96.0% and 94.3%) and hospitalization periods (7 days and 7 days) were similar between overseas and domestic dogs. This report shows that taking air flights in the cabin may not have a significant effect on dogs with MMVD, on the premise that their overall conditions are stable under cardiac medication.

Abnormal movement of the pulmonary valve in dogs diagnosed with patent ductus arteriosus.

In the typical left-to-right patent ductus arteriosus (PDA), the shunt flows from the ductus arteriosus towards the pulmonary valve. Although hemodynamic changes have been carefully studied in dogs with PDA, there is very little information on the outcomes of the pulmonary valve after surgical correction of PDA. This study aimed to visualize the pulmonary valve by transthoracic echocardiography in dogs with PDA before and after surgical ligation. Prior to surgery, the movement of the anterior semilunar cusp of the pulmonary valve was obstructed by the shunted blood flow during systole in all nine dogs with PDA in this study. M-mode echocardiography revealed a continuous trajectory of the cusp, because the cusp was pushed towards the right ventricle during the whole cardiac cycle by the shunted flow. Epicardial echocardiography performed in one dog during surgical ligation of the ductus arteriosus revealed that the movement of the anterior semilunar cusp normalized immediately after ligation. B- and M-mode echocardiography may be used to support the diagnosis of PDA through observation of the pulmonary valve when color Doppler echography is not available. The findings in this study may be of importance in distinguishing PDA from PDA-mimicking diseases worth considering before the treatment process (e.g. aorticopulmonary fistulas or aberrant arteriovenous shunts).

Antemortem diagnosis of anomalous origin of the left coronary artery from the pulmonary artery in a dog.

BACKGROUND: In both humans and animals, anomalous origin of the left coronary artery from the pulmonary artery (ALCAPA) is a rare congenital coronary artery anomaly. In veterinary medicine, ALCAPA is reported to be discovered only during autopsy or necropsy, and diagnostic methods and prognosis remain poorly understood in dogs. CASE PRESENTATION: A 6-month-old Kaninchen Dachshund was diagnosed with functional mitral valve regurgitation and ALCAPA. Echocardiography identified anomalous vessels in the left ventricular wall and abnormal origin of the left coronary artery from the pulmonary artery. Further evaluation with coronary computed tomographic angiography demonstrated the left coronary artery arising from the posterior aspect of the main pulmonary artery together with the characteristic findings of ALCAPA. The right coronary artery was found to be dilated and tortuous. Furthermore, dilated coronary collateral arteries within the ventricular septum and along the epicardial surface were observed. The dog underwent surgery, but the origin of the anomalous artery could not be ligated, and it died from pulmonary edema 5 months after surgery. CONCLUSION: Anomalous origin of the left coronary artery from the pulmonary artery is overlooked in clinical practice due to its rarity. Coronary computed tomographic angiography was useful to definitively diagnose ALCAPA in a low-invasive manner. Antemortem diagnosis of ALCAPA was shown to be possible in dogs for the first time, and presence of unexplained mitral valve regurgitation should raise concern to this anomaly.

Unilateral diaphragmatic paralysis associated with surgical mitral valve repair in dogs.

OBJECTIVES: Unilateral diaphragmatic paralysis (UDP) due to phrenic nerve injury is a potential complication of thoracic surgery. This study evaluated the prevalence of UDP associated with surgical mitral valve repair (MVR) and its effect on surgical outcomes in dogs. ANIMALS, MATERIALS AND METHODS: Two hundred ninety-four dogs that underwent MVR were included in the study. A retrospective review of medical records was performed for dogs surviving surgery. Diagnosis of UDP was based on preoperative and postoperative thoracic dorsoventral radiographs. RESULTS: A total of 284 dogs survived until the day after surgery. The prevalence of UDP on the day after surgery, on the day of discharge, and after the first postoperative month was 30%, 24%, and 9%, respectively. One case of UDP was observed at 3 months after surgery. Unilateral diaphragmatic paralysis was exhibited by nine of the 21 patients that died in the hospital. The proportion of patients with UDP was higher in dogs that died of respiratory failure than in dogs that died of other causes (p = 0.002). Most dogs whose deaths were suspected to have been related to respiratory failure also had pre-existing respiratory diseases. The occurrence of UDP did not relate to the lengths of stay in the intensive care unit or the hospital. CONCLUSIONS: Our findings suggest that UDP is a common complication in dogs after MVR and that the prevalence of UDP decreases with time after surgery. Unilateral diaphragmatic paralysis is a risk factor for postoperative death, especially in patients with pre-existing respiratory disease.