Plasma N-terminal pro B-type natriuretic peptide concentrations in dogs with pulmonic stenosis

Age of puppies at referral to veterinary cardiology specialists for murmur investigation

Background

Cardiac auscultation is an important screening test at the first health examination of puppies because most clinically relevant congenital cardiac anomalies cause a loud murmur from birth. This retrospective study aimed to investigate the age at which dogs with suspected congenital cardiac anomalies were referred to a veterinary cardiology specialist for murmur investigation. A secondary aim was to establish the time interval between the visit to the cardiologist and the first available murmur documentation. The digital archive of a veterinary teaching hospital was searched for dogs with congenital cardiac anomalies and puppies with innocent murmurs during a 5-year period. Dogs had to be referred because of a murmur, and they had to undergo physical examination and echocardiography by a veterinary cardiology specialist. The health certificate section of the pet passport, and the medical records from the referring veterinarian, were reviewed to identify the date when the murmur was first documented.

Results

Of the 271 included dogs, 94% had a congenital cardiac anomaly and 6% had an innocent murmur. The dogs’ median age was 190 days when they were examined by the cardiologist. Only 10% of the dogs were referred by the breeder’s veterinarian, while 90% of the dogs were referred by the new owner’s veterinarian. The median age of the first available murmur documentation by a first opinion veterinary practitioner was 95 days.

Conclusions

Only 10% of the puppies in the present study were referred to a veterinary cardiology specialist for murmur investigation before they were sold to a new owner. Referral prior to re-homing would have been feasible if the murmur had been detected and documented by the breeder’s veterinarian, if referral was offered by the breeder’s veterinarian and the referral was accepted by the breeder.

Serum N-Terminal Pro-B-Type Natriuretic Peptide as a Biomarker of Critical Pulmonary Stenosis in Neonates

Objectives: To determine the efficacy of serum N-terminal pro-B-type natriuretic peptide (NT-proBNP) levels in predicting critical pulmonary stenosis (CPS) in neonates. Methods: All neonates with pulmonary stenosis (PS) admitted to the neonatal intensive care unit of Xinhua Hospital from October 2014 to December 2020 were retrospectively reviewed. Infants with serum NT-proBNP levels measured within 48 h after birth were enrolled and divided into CPS and non-CPS groups. Serum NT-proBNP levels and cardiac Doppler indices were compared between the two groups. Correlations were determined using the Spearman's rank correlation coefficient. Receiver operator characteristic curve analysis was used to explore the predictive value of NT-proBNP for identifying neonatal CPS. Results: Among 96 infants diagnosed with PS by echocardiography, 46 were enrolled (21 and 25 in the non-CPS and CPS groups, respectively). Serum NT-proBNP levels were significantly higher in the CPS group than in the non-CPS group [3,600 (2,040-8,251) vs. 1,280 (953-2,386) pg/ml, P = 0.003]. Spearman's analysis suggested a positive correlation between Ln(NT-proBNP) levels and the transvalvular pulmonary gradient (r = 0.311, P = 0.038), as well as between Ln(NT-proBNP) levels and pulmonary artery velocity (r = 0.308, P = 0.040). Receiver operating characteristic curve analysis showed that a cutoff serum NT-proBNP level of 2,395 pg/ml yielded a 66.7 and 78.9% sensitivity and specificity for identifying CPS, respectively. The area under the curve was 0.784 (95% CI, 0.637-0.931). A positive correlation was found between Ln(NT-proBNP) and length of hospital stay (r = 0.312, P < 0.05). Conclusion: Serum NT-proBNP level was positively correlated with PS severity and could be used as a biomarker to identify CPS in neonates.

Evaluation of heart rate variability and behavior of electrocardiographic parameters in dogs affected by chronic Monocytic Ehrlichiosis

Canine Monocytic Ehrlichiosis (CME) is a systemic disease prevalent in the entire world caused by the obligate intracellular bacteria Ehrlichia canis. The occurrence of myocarditis with a high prevalence of arrhythmias in dogs affected by this disease in the cytopenic phase has already been proven. This study aims to evaluate the concentrations of CK MB, cTnI and NT-proBNP in dogs affected by Ehrlichia canis in the chronic phase since the intense stimulation of the immune system can lead to myocarditis; to evaluate if the condition can lead to arrhythmic events and, if so, define their frequency and classification through conventional and ambulatory electrocardiogram tests (Holter method) for a period of 24 hours; to analyze heart rate variability in the time domain and whether the condition can lead to autonomic imbalance; and to determine the survival rate of affected dogs, identifying possible risk factors for mortality at this stage of the disease. For this purposes, we evaluated clinical, hematological and biochemical data, as well as the concentrations of cardiac biomarkers Creatine Kinase-MB (CK MB), Cardiac Troponin I (cTnI) and N-terminal pro-peptide natriuretic type B (NT-proBNP). We also analyzed conventional and ambulatory electrocardiography (24-hour Holter) and heart rate variability (HRV) in 20 dogs afflicted by cytopenic CME in the chronic phase of the disease (G1) and compared the results with a control group comprised of ten healthy dogs (G2). G1 was monitored during the treatment for 28 days, during which eight (8) of the 20 infected dogs died (40%). Anorexia, vomiting, fatigue, hypoalbuminemia, heart murmurs and increased concentrations of alanine aminotransferase (ALT) and alkaline phosphatase (ALP) were common clinical signs. The mean concentrations of cTnI and CKMB were significant (0.24 ng / mL ± 0.5, 229 ± 205 IU / mL) in comparison to the control group (0.042 ± 0.07 ng / mL, 126 ± 46.12 IU / mL). No significant differences were observed between NT-proBNP concentrations in G1 (135.46 ± 29.7) and G2 (138.28 ± 19.77). Nine of the twenty dogs (45%) presented a high frequency of arrhythmias during 24-hour recording, ranging from first and second-degree atrioventricular block, ventricular and supraventricular ectopic events and sinus tachycardia. No sinus pause was observed. One dog had 120 episodes of unsustained ventricular tachycardia and two episodes of sustained ventricular tachycardia. The short-term and long-term HRV data, represented by SDNN (ms), SDANN (ms) and pnn50 (%) were also significant lower (83 ± 65, 56.05 ± 37.3 and 14.56 ± 20, respectively) in comparison to the healthy animals (268 ± 74.6, 168.3 ± 39.14 and 55.87 ± 12.8, respectively). These results suggest that cytopenic CME is characterized by an arrhythmogenic component and intense stimulation of the sympathetic autonomic nervous system in the heart, reflecting an imbalance in the activity of the ANS.

N-terminal-pro brain natriuretic peptides in dogs and cats: A technical and clinical review

Biomarkers are quantitative indicators of biological processes performed by an organ or system. In recent years, natriuretic peptides (NPs) have emerged as important tools in the diagnosis and therapeutic monitoring of heart diseases. Research has shown that serum and plasma levels of N-terminal pro brain NP (NT-proBNP) in dogs and cats are the only biomarkers that afford to diagnose and monitor congestive processes and, indirectly, the myocardial function of small animals. The present review discusses the peer-reviewed specialized literature about NT-proBNP and presents and compares the potential clinical applications of this NP in veterinary medicine of small animals, considering diagnosis, follow-up, and prognosis of myocardial or systemic diseases. The relevance of NT-proBNP is associated with sample stability, easy determination in laboratory, sensitivity, accuracy, and the possibility to analyze myocardial function. These advantages are specially important when NT-proBNP is compared with other cardiac biomarkers, mostly those that indicate the integrity of the myocardial cell. Fast NT-proBNP assays are marketed today and may be used in association with complementary tests. Together, these methods are an important source of information in differential diagnosis of heart and lung diseases as well in the early diagnosis of cardiopathy in dogs and cats, proving valuable tools in treatment and prognosis.

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.

Plasma atrial natriuretic peptide and N-terminal pro B-type natriuretic peptide concentrations in dogs with right-sided congestive heart failure

The clinical utility of plasma natriuretic peptide concentrations in dogs with right-sided congestive heart failure (CHF) remains unclear. We investigated whether plasma levels of atrial natriuretic peptide (ANP) and N-terminal pro B-type natriuretic peptide (NT-proBNP) are useful for assessing the congestive signs of right-sided heart failure in dogs. This retrospective study enrolled 16 healthy dogs and 51 untreated dogs with presence (n=28) or absence (n=23) of right-sided CHF. Medical records of physical examinations, thoracic radiography and echocardiography were reviewed. The plasma concentration of canine ANP was measured with a chemiluminescent enzyme immunoassay. Plasma NT-proBNP concentrations were determined using an enzyme immunoassay. Plasma ANP and NT-proBNP concentrations in dogs with right-sided CHF were significantly higher than in healthy controls and those without right-sided CHF. The plasma NT-proBNP concentration >3,003 pmol/l used to identify right-sided CHF had a sensitivity of 88.5% and specificity of 90.3%. An area under the ROC curve (AUC) was 0.93. The AUC for NT-proBNP was significantly higher than the AUCs for the cardiothoracic ratio, vertebral heart score, ratio of right ventricular end-diastolic internal diameter to body surface area, tricuspid late diastolic flow and ratio of the velocities of tricuspid early to late diastolic flow. These results suggest that plasma ANP and NT-proBNP concentrations increase markedly in dogs with right-sided CHF. Particularly, NT-proBNP is simple and helpful biomarkers to assess the right-sided CHF.