Therapeutic changes of plasma N-terminal pro-brain natriuretic peptide concentrations in 9 dogs with patent ductus arteriosus

N-Terminal Pro-B-Type Natriuretic Peptide and Phonocardiography in Differentiating Innocent Cardiac Murmurs from Congenital Cardiac Anomalies in Asymptomatic Puppies

BACKGROUND

Differentiating innocent cardiac murmurs from murmurs caused by congenital cardiac anomalies can be challenging with auscultation alone in asymptomatic puppies.

HYPOTHESIS

Plasma N-terminal pro-B-type natriuretic peptide (NT-proBNP) concentrations and phonocardiograms recorded by an electronic stethoscope can differentiate innocent from pathologic cardiac murmurs.

ANIMALS

A total of 186 client-owned asymptomatic dogs: 135 Cairn Terriers (age: 45-124 days), 20 adult Cairn Terriers (age: 7.5 months to 13.5 years), and 31 puppies of various breeds (age: 29-396 days).

METHODS

Study design is a cross-sectional survey. Each dog was auscultated, and when a cardiac murmur was heard, a phonocardiogram was recorded and an echocardiogram was performed. Plasma NT-proBNP concentrations were measured by a single laboratory by an ELISA.

RESULTS

No significant (P = .41) difference in plasma NT-proBNP levels was found between puppies without a murmur and puppies with an innocent murmur (median 300 versus 326 pmol/L), and between clinically healthy adult Cairn Terriers and Cairn Terrier puppies. Plasma NT-proBNP levels in puppies with a congenital heart disease were significantly (P < .001) higher than those in puppies with innocent murmurs (median 1,102 versus 326 pmol/L). However, some puppies with severe pulmonic stenosis did not have increased plasma NT-proBNP levels. On phonocardiograms, innocent murmurs had a significantly (P < .001) shorter "murmur-to-systole duration ratio" than the abnormal ones (median 66 versus 100%). The "murmur-to-S1 (first cardiac sound) amplitude ratio" was significantly (P < .001) lower of the innocent murmurs compared with that of the abnormal ones (median 16 versus 58 %).

CONCLUSIONS AND CLINICAL IMPORTANCE

Plasma NT-proBNP concentrations within the reference range do not rule out a congenital cardiac anomaly. Murmurs longer than 80% of the systole are most likely abnormal, whereas murmurs shorter than that could be either innocent or pathologic.

Promotion of artery occlusion in dogs by percutaneous rotational atherectomy

BACKGROUND

This study aims to offer experimental data and indirect evidences for the application of percutaneous rotational atherectomy to treat patent ductus arteriosus (PDA).

METHODS

Eleven dogs (6 male dogs and 5 female dogs; aged 14-20 months, with an average of 16.7±3.2 months; weight 20-25 kg, with an average of 22.7±2.5 kg) were enrolled in this study. The diameters of the left and right arteries ranged from 3.2 to 4.8 mm (average 3.9±0.6 mm) on percutaneous angiography. Percutaneous rotational atherectomy with proper rotablator (the size was 1-1.5 mm larger than the artery diameter) was performed in the arterial intima. After 4 weeks from percutaneous rotational atherectomy, arteriography was conducted to observe the changes in artery diameter. Then all dogs were sacrificed and the pathologic examination was conducted on the left and right axillary arteries.

RESULTS

There were obvious changes with different degrees in 22 arteries, including 8 arteries with complete occlusion and 12 arteries with stenosis (≥2/3, 1/2, and 1/3 stenosis in 4, 4, and 4 arteries, respectively). The occlusion rate was 36.4% and the total effective rate was 90.9%. It was considered failure in other 2 arteries with <1/3 of stenosis.

CONCLUSIONS

Percutaneous rotational atherectomy of arterial intima can promote the occlusion of arteries. This has provided a new choice for the treatment of PDA.