This report described the influence of persistent left cranial vena cava (PLCVC) on mitral valve repair outcome in dogs with severe mitral regurgitation (MR). An 8-year-old male miniature schnauzer with history of syncope and a 13-year-old shih tzu with history of severe persistent cough were echocardiographically diagnosed with surgically indicated MR. They underwent open-heart surgery for mitral valve repair using cardiopulmonary bypass. Preoperative echocardiography revealed tricuspid valve regurgitation involvement in the shih tzu and the dog was supposed to be pulmonary hypertension. PLCVC adjacent to the left atrium was found perioperatively in both dogs. Tugging the persistent vessel dorsally permitted the conventional surgical approach for valve repair from the left atrium. Postoperative progress was favorable for the miniature schnauzer, but echocardiography of the shih tzu 3 days after surgery revealed a grade 5/6 right cardiac murmur augmented on auscultation and expanded PLCVC, because of worsening of pulmonary hypertension and tricuspid valve regurgitation, compressing the mitral valve annulet, resulting in distraction of normal blood flow from the left atrium to left ventricle. Sildenafil and diuretic treatment to alleviate right heart overload resulted in no improvement of the right heart overload, and the dog was euthanized 13 days after surgery because of severe dyspnea and hypothermia. PLCVC alone is rarely a subject of treatment; however, expanded PLCVC with tricuspidregurgitation and pulmonary hypertension may obstruct left ventricular inflow. Preoperative echocardiograph should be performed carefully to diagnose the existence of PLCVC. If found perioperatively, treatments such as persistent vessel bypass should be considered.

Pulmonic stenosis (PS) is one of the three most common congenital heart defects in dogs. Dogs with mild to moderate PS do not always require medical therapy, however, in severe cases they may exhibit symptoms or even sudden death could occur thus surgical intervention is indicated. We performed an open patch-graft technique under cardiopulmonary bypass in a PS dog. The dysplastic pulmonic valve leaflets were excised and patch grafting of the right ventricular outflow tract was applied to reduce the severity of the right ventricular outflow tract obstruction. This report describes the histopathologic findings of mucinous degenerative changes of the pulmonic valve leaflets in a dog with severe PS.

A 7-year old male intact Pomeranian was presented for mitral valve repair (MVR) surgery. The dog was diagnosed with ACVIM Stage B2 and underwent MVR under cardiopulmonary bypass. The MVR was uneventful and the patient was transferred to ICU after weaning from general anesthesia. One hour and 20 minutes later, respiratory arrest was observed and blood test revealed hypoglycemia. Glucose injection (25% glucose at 1ml/kg slow IV) was initiated immediately and his breathing had stabilized following glucose administration. At two months postoperative and there has been no signs of hypoglycemia in this patient and require no medical therapy. Intraoperative hyperglycemia has been reported to be associated with poor prognosis in human medicine. In dogs, serum glucose levels during cardiac surgery is unclear and require further studies are warranted in order to avoid both hyperglycemia and hypoglycemia.