Successful balloon angioplasty of pulmonary artery stenosis in two cats and associated complications.

Two cats (2.5 months and 8 months old) were each evaluated due to a loud systolic murmur, and each was diagnosed with severe pulmonary artery stenosis at the bifurcation of the main pulmonary artery. Echocardiograms confirmed significant right atrial dilation and right ventricular dilation and/or hypertrophy that was progressive in one cat. Atenolol was initiated and the cats were referred for interventional therapy. Balloon angioplasty was performed via the jugular vein. In case 1, the pressure gradient across the stenosis was reduced from 169.7 mmHg to 23.6 mmHg and 52.4 mmHg across the left and right branch pulmonary arteries, respectively. In case 2, the stenotic echocardiographic gradient was reduced from 64 mmHg to 38.0 mmHg and 35.3 mmHg across the left branch and right-branched pulmonary arteries respectively. Both patients developed moderate to severe dynamic right ventricular outflow tract obstruction post angioplasty. Case 2 developed hypotension, desaturation, and ventricular arrhythmias intra-operatively. Case 1 was discharged but appeared to develop acute lung perfusion injury approximately 36 h after procedure that was manifested by radiographic pulmonary congestion and pulmonary infiltrate of the left lung fields. The congestion was successfully managed medically. Serial echocardiograms over the following 4 years in case 1 showed near complete resolution of the stenosis and associated right heart enlargement.

Use of pericardial fluid pH to distinguish between idiopathic and neoplastic effusions.

Pericardial effusion (PE) resulting from neoplasia usually is associated with a poor prognosis, whereas idiopathic PE frequently has a good prognosis. This study examined the utility of pH measurement to distinguish between these 2 etiologies. Dogs were classified as having idiopathic PE (n = 12) if pericarditis was diagnosed on histopathology (n = 4) or if no historical, physical, or echocardiographic evidence of recurrent PE was present for at least 6 months after pericardiocentesis (n = 8). Dogs were classified as having neoplastic PE (n = 25) if pericardial or myocardial neoplasia was detected on histopathology (n = 11) or a discrete mass associated with the right atrium, right ventricle, or the aorta was visualized on echocardiography (n = 14). Samples of PE were centrifuged and the supernatant pH was measured with a portable pH meter. The lowest pH (6.40) was found in a dog with idiopathic PE and the highest pH (7.85) was found in a dog with neoplastic PE. However, data from the 2 groups overlapped in 33 out of 37 (89%) instances, and median pH from the idiopathic and neoplastic groups was not significantly different (7.40 and 7.47, respectively; P = 0.28; difference in medians = -0.7; 95% CI, -0.26-0.06). Because of the degree of overlap, our data provide little justification for the use of pH measurement as a diagnostic test in cases of PE.

Arterial thromboembolism in cats: acute crisis in 127 cases (1992-2001) and long-term management with low-dose aspirin in 24 cases.

Records of 127 cats with arterial thromboembolism (ATE) were reviewed. Abyssinian, Birman, Ragdoll, and male cats were overrepresented. Tachypnea (91%), hypothermia (66%), and absent limb motor function (66%) were common. Of 90 cats with diagnostics performed, underlying diseases were hyperthyroidism (12), cardiomyopathy (dilated [8], unclassified [33], hypertrophic obstructive [5], hypertrophic [19]), neoplasia (6), other (4), and none (3). Common abnormalities were left atrial enlargement (93%), congestive heart failure (CHF, 44%), and arrhythmias (44%). Of cats without CHF, 89% were tachypneic. Common biochemical abnormalities were hyperglycemia, azotemia, and abnormally high serum concentrations of muscle enzymes. Of 87 cats treated for acute limb ATE, 39 (45%) survived to be discharged. Significant differences were found between survivors and nonsurvivors for temperature (P < .00001), heart rate (P = .038), serum phosphorus concentration (P = .024), motor function (P = .008), and number of limbs affected (P = .001). No significant difference was found between survivors and nonsurvivors when compared by age, respiratory rate, other biochemical analytes, or concurrent CHE A logistic regression model based on rectal temperature predicted a 50% probability of survival at 98.9 degrees F (37.2 degrees C). Median survival time (MST) for discharged cats was 117 days. Eleven cats had ATE recurrences, and 5 cats developed limb problems. Cats with CHF (MST: 77 days) had significantly shorter survival than cats without CHF (MST: 223 days; P = .016). No significant difference was found in survival or recurrence rate between cats receiving high-dose aspirin (> or = 40 mg/cat q72h) and cats receiving low-dose aspirin (5 mg/cat q72h). Adverse effects were less frequent and milder for the lower dosage.

Supravalvular mitral stenosis in a cat.

A 3-year-old, 4-kg, castrated male domestic shorthair cat presented with signs of progressive respiratory distress. Thoracic radiographs showed pulmonary edema and pleural effusion. Echocardiography revealed a perforate membrane immediately above the mitral valve that divided the left atrium into proximal and distal chambers. The left auricle was proximal to the dividing membrane and connected to the markedly enlarged proximal left atrial chamber, consistent with the diagnosis of supravalvular mitral stenosis (SMS). Position of the obstructing membrane relative to the left auricle distinguishes SMS from cor triatriatum sinister (CTS). In CTS, the left auricle is distal to the dividing membrane and connects to the distal left atrial chamber.