Potential prognostic indicators in dogs with advanced heart failure secondary to myxomatous mitral valve disease.

BACKGROUND: Advanced heart failure (AHF) secondary to myxomatous mitral valve disease (MMVD) in dogs has unclear predictive variables and survival time. METHODS: This retrospective study included 38 dogs with AHF and 38 with stable congestive heart failure (CHF), both due to MMVD. Predictive variables for AHF were analysed, and survival times were calculated using logistic regression and the Kaplan-Meier method. RESULTS: Left atrium to aortic root ratio, normalised left ventricular dimension at the end-diastole and end-systole, isovolumic relaxation time (IVRT) and early transmitral inflow velocity to IVRT ratio were associated with AHF progression. The median survival times were significantly longer in the stable group than in the AHF group. After AHF diagnosis, the median survival times for all-cause and cardiogenic mortality were 194 and 354 days, respectively. LIMITATIONS: This was a single-centre retrospective observational study. The study population was small, with breed bias (overrepresentation of Maltese dogs). Additionally, the treatment plans depended on clinical experience. CONCLUSIONS: AHF in dogs with CHF secondary to MMVD is linked to left heart chamber enlargement and increased left ventricular dimensions, significantly reducing survival time to around six months post-diagnosis. Early recognition and appropriate management may improve outcomes, highlighting the importance of advanced treatment strategies.

Pulse-wave analysis during routine blood pressure measurement shows potential to distinguish between sinus and nonsinus rhythm.

OBJECTIVE: To investigate whether pulse-wave analysis (PWA) performed by trained evaluators facilitates detection of nonsinus rhythm. ANIMALS: Same-day, high-definition oscillometry pulse-wave data and ECG results of 155 animals (144 dogs and 11 cats) were analyzed. METHODS: In this cross-sectional study, we enrolled 18 participants from various backgrounds, all of whom received PWA training. The ability to distinguish between sinus and nonsinus rhythms was assessed using receiver operating characteristic curve analysis. The pulse-wave datasets were divided into 5 ECG categories. Agreement between ECG diagnoses and PWA-based arrhythmia detection was evaluated using Cohen κ values, and the correlation between the academic year of veterinary students and their κ values was assessed. RESULTS: All cardiology researchers demonstrated satisfactory accuracy in distinguishing pathological rhythms using PWA (area under the curve, 0.704 to 0.761), with the highest accuracy in detecting atrial fibrillation (area under the curve, 0.811 to 0.845). Fair agreement with ECG categorization was achieved by all 3 cardiology researchers, 2 of 5 general practitioners, and 3 of 10 veterinary undergraduates. The veterinary undergraduates' years of study were correlated with their diagnostic performance (Spearman ρ = 0.658; P = .019). CLINICAL RELEVANCE: PWA during routine noninvasive blood pressure measurement showed significant potential for the detection of pathological arrhythmias, notably atrial fibrillation. This approach yielded improved effectiveness when it was used by veterinarians with cardiology experience. Thus, introducing hands-on training courses, particularly those focused on cardiology and interactive workshops, may enable frontline veterinarians to promptly identify arrhythmias using PWA, facilitating timely ECG examinations or referrals.

Comparative electrocardiographic study of the Asian freshwater box turtle Cuora flavomarginata and the Asian yellow pond turtle Mauremys mutica using non-invasive methods.

Background: Evaluation of cardiac function is an integral part of clinical examination of chelonians. However, information about electrocardiography (ECG) in turtles and tortoises is limited and fragmentary. Its application is limited due to the lack of ECG reference values. This study aimed to compare specific ECG parameters using non-invasive methods in the Asian box turtle Cuora flavomarginata (CF) and the Asian yellow pond turtle Mauremys mutica (MM). Methods: We included 116 clinically healthy and conscious turtles. Two non-invasive methods, using adhesive patches or crocodile clips, for ECG were applied where possible. The ambient temperature was within the preferred optimum temperature zone of both species. We used specific digital ECG monitoring equipment to record the ECG data and analysed the data using specific software. Results: The MM group showed better ECG quality and lower heart rate than the CF group. Comparing both methods, the adhesive patches method yielded higher ECG quality in the CF group, while the crocodile clips method yielded higher ECG quality in the MM group. Conclusions: The study population was selected as presumed healthy turtles; the presence of systemic or cardiac disease could not be excluded completely due to limited investigation. Both ECG methods were clinically potentially useful for obtaining ECG parameters; the ECG quality was influenced by the method used.

Symptomatic partial anomalous pulmonary venous connection in a kitten.

A 3-month-old intact female American Shorthair cat, with syncope and tachypnea, underwent cardiac examination which identified no heart murmur or gallop. Thoracic radiography disclosed mild generalized enlargement of the cardiac silhouette and a bronchial and interstitial pattern throughout the lungs. Echocardiography identified tubular structures near the left atrium. After agitated saline contrast imaging, persistent left cranial vena cava with unroofed coronary sinus was suspected. Computed tomography angiography showed the right cranial, right caudal and left caudal pulmonary veins draining into the coronary sinus and flowing into the right atrium. The left cranial pulmonary vein drained normally into the left atrium. Partial anomalous pulmonary venous connection (PAPVC) was diagnosed. The kitten was treated with diuretics but died of heart failure 2 months later. Permission for necropsy was not granted. This case represents symptomatic PAPVC in a kitten. Most pulmonary veins were connected abnormally with the coronary sinus. The prognosis was grave because of refractory heart failure.

Serial measurements of cardiac troponin I in heart failure secondary to canine mitral valve disease.

Serial measurements of cardiac troponin I (cTnI) levels are considered to be better predictors of cardiac death than single-time-point analyses in human medicine. We hypothesised that cTnI levels could reflect the severity of myxomatous mitral valve disease (MMVD), and that serial changes in the cTnI level had a prognostic value in dogs with congestive heart failure (CHF) secondary to MMVD. Seventy-six dogs were initially enrolled and classified by the American College of Veterinary Internal Medicine (ACVIM) staging system. The single-timepoint cTnI concentration in these dogs significantly increased with the ACVIM stage. Twenty-seven dogs with CHF subsequently underwent serial measurement of cTnI levels, and the results showed that those who demonstrated a decrease in cTnI levels from the first to the third visit exhibited a higher risk of cardiac death than did those without such changes (P=0.012). We suspect that the downward trend in cTnI levels may be affected by medical treatment for CHF. In conclusion, although cTnI levels could reflect the severity of MMVD to a certain extent, the serial changes may be affected by medical treatment. Therefore, caution should be exercised when cTnI is used for assessment of the prognosis of CHF secondary to MMVD in dogs.

Prognostic value of right pulmonary artery distensibility in dogs with pulmonary hypertension.

The right pulmonary artery distensibility (RPAD) index has been used in dogs with pulmonary hypertension (PH) caused by heartworm infection, myxomatous mitral valve disease, or patent ductus arteriosus. We hypothesized that this index correlates with the tricuspid regurgitation pressure gradient (TRPG) assessed by echocardiography and could predict survival in dogs with PH secondary to various causes. To assess this hypothesis, the medical records of 200 client-owned dogs at a referral institution were retrospectively reviewed. The RPAD index and the ratios of acceleration time to peak pulmonary artery flow (AT) and to the ejection time of pulmonary artery flow (ET) were recorded for each dog. The owners were contacted for follow-up assessments. The findings indicated that the RPAD index was correlated with the TRPG (R² = 0. 362, p < 0.001). The survival time was significantly shorter in dogs with an RPAD index ≤ 21% that were followed up for 3 months and in dogs with an RPAD index ≤ 24% that were followed up for 1 year. Thus, the RPAD index was correlated with the TRPG and could predict the clinical outcome in dogs with PH caused by various diseases. This index could be used to evaluate the severity of PH in dogs without tricuspid regurgitation.

Electrochemically monitoring the antibiotic susceptibility of Pseudomonas aeruginosa biofilms.

The condition of cells in Pseudomonas aeruginosa biofilms was monitored via the electrochemical detection of the electro-active virulence factor pyocyanin in a fabricated microfluidic growth chamber coupled with a disposable three electrode cell. Cells were exposed to 4, 16, and 100 mg L(-1) colistin sulfate after overnight growth. At the end of testing, the measured maximum peak current (and therefore pyocyanin concentration) was reduced by approximately 68% and 82% in P. aeruginosa exposed to 16 and 100 mg L(-1) colistin sulfate, respectively. Samples were removed from the microfluidic chamber, analyzed for viability using staining, and streaked onto culture plates to confirm that the P. aeruginosa cells were affected by the antibiotics. The correlation between electrical signal drop and the viability of P. aeruginosa cells after antibiotic exposure highlights the usefulness of this approach for future low cost antibiotic screening applications.

Electrochemical detection of Pseudomonas aeruginosa in human fluid samples via pyocyanin.

The ability to quickly detect the presence of pathogenic bacteria in patient samples is of the outmost importance to expedient patient care. Here we report the direct, selective, and sensitive detection of the opportunistic pathogen Pseudomonas aeruginosa, spiked in human whole blood with sodium heparin, urine, sputum, and bronchial lavage samples using unmodified, disposable carbon electrode sensors that detect the presence of pyocyanin, a virulence factor that is unique to this species. Square wave voltammetry scans of biological fluids from healthy individuals spiked with P. aeruginosa showed a clear pyocyanin response within one day of culturing at 37°C. Scans of supernatants taken from cultures of P. aeruginosa, Escherichia coli, Staphylococcus aureus, Staphylococcus epidermis, and Bacillus cereus taken over a span of three days in the potential range from -0.5 to 0 V vs. an Ag/AgCl reference showed no electrochemically detectable molecules with the exception of P. aeruginosa. The results indicate the potential to sensitively and selectively determine the presence of P. aeruginosa in human samples via the electrochemical detection of pyocyanin in less than 5 min, without any sample preparation or separation steps.

Relationship between age, plasma renin activity, and renal resistive index in dogs.

The renal resistive index (RI) value of 0.73 has been proposed as the upper limit in normal adult dogs. In humans, changes in RI with age are associated with plasma renin activity. There are relatively few equivalent reference data for dogs. We obtained reference RI data from 22 clinically healthy dogs <4 months of age and 33 healthy dogs between 4 months and 7 years of age. An association between the RI and plasma renin activity was investigated. The mean RI in the older dogs was 0.65 +/- 0.05 vs. 0.75 +/- 0.05 in dogs <4 months of age. The mean plasma renin activity in the older dogs was 1.18 +/- 1.03 vs. 4.23 +/- 3.09 ng/ml/h in dogs <4 months of age. There was a weak linear relationship between the RI and plasma renin activity (r2 = 0.280, P < 0.01) in dogs <4 months of age. Also in these younger dogs, RI was negatively correlated with age (r2 = 0.682, P < 0.01). The RI was higher in dogs <4 months of age than in older dogs. Therefore, the mean renal RI is slightly higher in young dogs than reported for an older population and interpretation of the RI must include an assessment of patient age.

Association between expression of human papillomavirus 16/18 E6 oncoprotein and survival in patients with stage I non-small cell lung cancer.

The clinical significance of HPV-16/18 E6 oncoprotein expression in non-small cell lung cancer (NSCLC) is not fully known. A study was undertaken to investigate the association between expression of human papillomavirus 16/18 E6 oncoprotein and survival in patients with stage I NSCLC. We analyzed a series of 217 patients with stage I NSCLC for the presence of HPV-16/18 E6 oncoprotein by immunohistochemistry. HPV-16 E6 oncoprotein was expressed in 49 (22.6%) patients and HPV-18 E6 oncoprotein was expressed in 31 (14.3%) patients. Statistical analysis revealed that the prevalence of expression of HPV-16 and HPV-18 E6 oncoproteins was significantly high in female patients, nonsmokers and patients with adenocarcinoma. The adjusted odds ratio for expression of HPV-16 E6 oncoprotein in female patients was 2.275 [95% confidence interval (CI), 0.999-5.179] and that in patients with adenocarcinoma was 2.320 (95% CI, 1.029-5.232). These ratios were significantly higher than those in male patients and patients with squamous cell carcinoma. Interestingly, we found that the 17 patients who expressed HPV-16 and HPV-18 E6 oncoprotein had a higher 5-year cumulate survival rate (72.2%) than the 154 patients who did not express both oncoproteins (48.3%); the difference was significant (p=0.055). Expression of HPV-16/18 E6 oncoprotein in stage I NSCLC may play an important role in female adenocarcinoma patients and survival benefits in patients who expressed HPV-16 and HPV-18 E6 oncoprotein.