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OBJECTIVES/HYPOTHESIS: The purpose of this study was to determine the effect of level and type of experience on response time and the number of replays needed when judging voice quality. STUDY DESIGN: This was a within-subjects group design. METHODS: Speech-language pathologists, singing voice teachers, speech-language pathology graduate students with and without experience with a voice client, graduate students who have completed a voice pedagogy course, and inexperienced listeners (n = 60) rated stimuli with systematically altered measurements of jitter, shimmer, and noise-to-harmonics ratio (NHR) on a visual analog scale ranging from mild to severe for overall severity, roughness, breathiness, strain, and pitch. Response time (in seconds) and number of replays were recorded during the experiment. RESULTS: Results showed that experienced listeners took the most time when rating the stimuli. Stimuli with two altered acoustical components also yielded longer response times compared with the stimuli with one altered acoustical component. Finally, level and type of experience had some effect on the number of replays for each stimulus during the rating task. CONCLUSIONS: In conclusion, experience does affect response time when judging voice quality and the number of replays during voice quality rating tasks. Continued research is needed regarding the reasons for extended time and replays as per experience so as to enhance future training protocols.

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OBJECTIVES/HYPOTHESIS: The purpose of this study was to determine the effect of experience on the perceptual space of listeners when judging voice quality. STUDY DESIGN: This was a within-subjects group design. METHOD: Speech-language pathologists, singing voice teachers, speech-language pathology graduate students with and without experience with a voice client, graduate students who have completed a voice pedagogy course, and inexperienced served as listeners. Each participant rated the similarity of pairs of synthesized stimuli with systematically altered measurements of jitter, shimmer, and noise-to-harmonics ratio on a visual analog scale ranging from no similarity to extremely similar. RESULTS: Results showed that participants with different levels and types of experience used different perceptual spaces (of additive noise and perturbation measures) when judging the similarity of stimulus pairs. CONCLUSION: The conclusion was that perceptual spaces differ among individuals with different levels and types of experience when judging the similarity of pairs of stimuli with systematically altered acoustical measurements.

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OBJECTIVES/HYPOTHESIS: The purpose of this study was to determine the effect of level and type of experience on the judgment of voice quality and to examine the correlation among acoustical measurements and perceptions of voice quality. STUDY DESIGN: This was a within-subjects group design. METHODS: Speech-language pathologists, singing voice teachers (SVTs), speech-language pathology graduate students with and without experience with a voice client, graduate students who have completed a voice pedagogy course, and inexperienced listeners (IEs) rated stimuli with systematically altered measurements of jitter, shimmer, and noise-to-harmonics ratio (NHR) on a visual analog scale ranging from mild to severe for overall severity, roughness, breathiness, strain, and pitch. RESULTS: Results showed that the type of experience had an impact on judgments of voice quality more than the level of experience. Also, jitter/shimmer combination stimuli and shimmer only stimuli frequently correlated with the ratings of overall severity, roughness, and strain, and NHR stimuli correlated with ratings of breathiness across all groups. Only IEs, SVTs, and their students had significant correlations for ratings of pitch with jitter/shimmer combination stimuli having the highest correlations. CONCLUSION: The conclusion was that the level and type of experience affect judgments of voice quality.

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Subvalvular aortic stenosis (SAS) is one of the most common congenital cardiac malformations in dogs. Unfortunately, the long term success rate and survival data following either open heart surgery or catheter based intervention has been disappointing in dogs with severe subaortic stenosis. Medical therapy is currently the only standard recommended treatment option. A cutting balloon dilation catheter has been used successfully for resistant coronary artery and peripheral pulmonary arterial stenoses in humans. This catheter is unique in that it has the ability to cut, or score, the stenotic region prior to balloon dilatation of the stenosis. The use of cutting balloon valvuloplasty combined with high pressure valvuloplasty for dogs with severe subaortic stenosis has recently been reported to be a safe and feasible alternative therapeutic option. The following report describes this technique, outlines the materials required, and provides some 'tips' for successful percutaneous subaortic balloon valvuloplasty.

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OBJECTIVES/HYPOTHESIS: The purpose of this study was to compare the agreement among several groups of listeners with different types of experience in regard to classifying voice quality. STUDY DESIGN: This is a retrospective cross-sectional quasi-experimental design. METHOD: This study compared three groups: speech-language pathologists who specialize in voice, singing voice teachers, and inexperienced listeners. All groups were asked to classify voice samples as breathy, rough, or normal. RESULTS: Results show a significant difference across all groups with speech-language pathologists demonstrating a substantial interrater agreement, κ=0.67, z=103.07 (P<0.01); singing voice teachers demonstrating a moderate interrater agreement, κ=0.53, z=79.10 (P<0.01); and inexperienced listeners demonstrating a fair interrater agreement, κ=0.24, z=35.82 (P<0.01). CONCLUSIONS: Experienced listeners demonstrated a higher interrater agreement as compared with inexperienced listeners, with speech-language pathologists demonstrating a superior agreement as compared with all groups.

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CASE DESCRIPTION: 2 spayed female (8 and 9 years old) and 1 sexually intact male (6.5 years old) Boxers were treated because of sustained ventricular tachycardia by electrical cardioversion. CLINICAL FINDINGS: Physical examination of the 8-year-old female Boxer revealed tachycardia (heart rate, 250 beats/min), weak femoral pulses, pale mucous membranes, panting, and lethargy. The 6.5-year-old male Boxer had similar physical examination findings, with the addition of a syncopal event. Analysis of the ECG rhythm strips for the 8- and 6.5-year-old dogs indicated a right ventricular origin of the ventricular tachycardia. The 9-year-old female Boxer was being treated with an IV constant rate infusion of lidocaine hydrochloride because of ventricular arrhythmias during the initial examination; physical examination re-vealed weakness, pale mucous membranes, prolonged capillary refill time, weak femoral pulses, and tachycardia (heart rate, 265 beats/min). Analysis of the ECG rhythm strip for the 9-year-old Boxer indicated a left ventricular origin of the ventricular tachycardia. TREATMENT AND OUTCOME: Pharmacological cardioversion treatment was unsuccessful in all 3 Boxers; however, electrical cardioversion by use of a biphasic defibrillator synchronized to conduct 30 J of energy during the peak of the QRS complex was successful in each dog. The electrical cardioversion procedure was performed 2 times (5-day interval between procedures) in the 9-year-old female as a result of relapse of the ventricular tachycardia condition. CLINICAL RELEVANCE: Results and follow-up monitoring suggested electrical cardioversion of sustained ventricular tachycardia may be a safe and effective treatment in Boxers that are unresponsive to medical treatment.

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Closure of reversed patent ductus arteriosus (PDA) is generally accepted to be contraindicated due to case based evidence of worsened outcomes, but little is known about closure of left-to-right PDA with concurrent pulmonary hypertension (PH). This report describes three dogs presenting with varying severity of PH and clinical signs, all with documented left-to-right PDA. The PDA was closed in each case; either by surgical ligation or transarterial device occlusion, and follow up was available for a minimum of 8 months. Every case had a successful outcome with improvement or resolution of PH and associated clinical signs.

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OBJECTIVE: To determine whether serum N-terminal pro-B-type natriuretic peptide (NT-proBNP) concentration is useful in discriminating between cardiac and noncardiac (ie, primary respiratory tract disease) causes of respiratory signs (ie, coughing, stertor, stridor, excessive panting, increased respiratory effort, tachypnea, or overt respiratory distress) in dogs. DESIGN: Multicenter cross-sectional study. ANIMALS: P 115 dogs with respiratory signs. PROCEDURES: Dogs with respiratory signs were solicited for study. Physical examination, thoracic radiography, and echocardiography were used to determine whether respiratory signs were the result of cardiac (ie, congestive heart failure) or noncardiac (ie, primary respiratory tract disease) causes. Serum samples for NT-proBNP assay were obtained at time of admission for each dog. Receiver-operating characteristic curves were constructed to determine the ability of serum NT-proBNP concentration to discriminate between cardiac and noncardiac causes of respiratory signs. RESULTS: Serum NT-proBNP concentration was significantly higher in dogs with cardiac versus noncardiac causes of respiratory signs. In dogs with primary respiratory tract disease, serum NT-proBNP concentration was significantly higher in those with concurrent pulmonary hypertension than in those without. A serum NT-proBNP cutoff concentration > 1,158 pmol/L discriminated between dogs with congestive heart failure and dogs with primary respiratory tract disease with a sensitivity of 85.5% and a specificity of 81.3%. CONCLUSIONS AND CLINICAL RELEVANCE: Measuring serum NT-proBNP concentration in dogs with respiratory signs helps to differentiate between congestive heart failure and primary respiratory tract disease as an underlying cause.

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OBJECTIVE: To compare left ventricular synchronization and systolic performance with transvenous pacing of the right ventricular apex (RVA), left ventricular free wall (LVF) or simultaneous pacing of the RVA and LVF (BiV). ANIMALS, MATERIALS AND METHODS: Seven canine patients with complete heart block. Prospective study evaluating effect of pacing site. Twenty four hours following implantation of transvenous BiV pacing systems, electrocardiograms and echocardiograms were assessed during pacing from the: (1) Right Atrial Appendage/RVA (RAA/RVA), (2) RAA/LVF, and (3) RAA/BiV. RESULTS: QRS duration was significantly shorter with BiV pacing versus LVF pacing (p<0.001), or RVA pacing (p<0.001). Echocardiographic indices of systolic performance fractional shortening (FS), ejection fraction (EF), cardiac output (CO) were significantly higher with BiV pacing than with pacing from the RVA (P=0.023, 0.006, and 0.002 respectively). Cardiac output, measured by the biplane Simpson's method, was higher with LVF versus RVA pacing (P=0.036). There was no difference in FS or EF when comparing LVF to RVA pacing. Tissue Doppler measurements of synchronization and systolic performance did not show any difference between pacing mode, but a significantly increased number of segments were seen to contract following aortic valve closure during LVF pacing (P=0.0268) and RVA pacing (P=0.0197) as compared to BiV pacing. CONCLUSIONS: Findings suggest that BiV pacing improves cardiac output and systolic performance versus RVA pacing. This improvement however, is not reflected in tissue Doppler indices of synchronization and systolic performance.

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OBJECTIVE: To determine changes in cardiac troponin I concentration (cTnI) associated with cardiovascular catheterization in dogs. ANIMALS, MATERIALS AND METHODS: cTnI was measured after transarterial coil embolization of patent ductus arteriosus (PDA), balloon valvuloplasty (BV), and pacemaker implantation (PACE). Dogs undergoing ovariohysterectomy (OHE) were used as a control, with 15 animals in each group. Blood for the cTnI assay was collected at baseline (T0), at 5h (T5), 24h (T24) and 10 days (T240) post-procedure. The effects of age, duration and difficulty of the procedure were evaluated. RESULTS: There was no difference in cTnI concentration at T0 for any of the groups. There was a significant increase in cTnI concentration for BV and PACE, but not PDA at T5 and T24. PACE at T24 and T240 also had higher cTnI than control. Dogs with longer procedure times had significantly higher concentration of cTnI. There was no correlation between the difficulty of the procedure or peri-procedure complications and cTnI. CONCLUSION: cTnI increased during some cardiovascular catheterization procedures, but returned to normal values at 24-240 h. Patients undergoing long catheterization procedures have increased risk for myocardial injury, but this was not related to short-term prognosis.

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OBJECTIVE-To compare the acute effects of cardiac pacing from various transvenous pacing sites on left ventricular (LV) function and synchrony in clinically normal dogs. ANIMALS-10 healthy adult mixed-breed dogs. PROCEDURES-Dogs were anesthetized, and dual-chamber transvenous biventricular pacing systems were implanted. Dogs were paced in single-chamber mode from the right atrial appendage (RAA) alone and in dual-chamber mode from the right ventricular apex (RVA), from the left ventricular free wall (LVFW), and simultaneously from the RVA and LVFW (BiV). Standard ECG and echocardiographic measurements, cardiac output measured with the lithium dilution method (LiDCO), and tissue Doppler-derived measurements of LV synchrony were obtained during each of the pacing configurations. RESULTS-Placement of the biventricular pacing systems was possible in 8 of the 10 dogs. The QRS duration was significantly different among all pacing sites, and the order of increasing duration was RAA, BiV, LVFW, and RVA. Pacing sites did not differ with respect to fractional shortening; however, pacing from the RVA resulted in a significantly lower ejection fraction than pacing from all other sites. During RVA and LVFW pacing, LiDCO was significantly lower than that at other sites; there was no significant difference between RAA and BiV pacing with respect to LiDCO. Although the degree of dyssynchrony was significantly lower during pacing from the RAA versus other ventricular pacing sites, it was not significantly different among sites. CONCLUSIONS AND CLINICAL RELEVANCE-Ventricular activation by RAA pacing provided the best LV function and synchrony. Pacing from the RVA worsened LV function, and although pacing from the LVFW improved it, BiV pacing may provide additional improvement.

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This study investigated the feasibility of using a modified transesophageal atrial pacing system for dogs requiring temporary ventricular pacing. Atrial pacing was readily achieved in the one dog studied, but it caused considerable diaphragmatic movement. Ventricular pacing could not be achieved at any lead configuration or energy stimulation. While transesophageal cardiac pacing was a safe procedure, the large variation in the chest anatomy of dogs requires further study to explore this model as a substitute for transvenous or transthoracic ventricular pacing.

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BACKGROUND: It is challenging to differentiate congestive heart failure (CHF) from noncardiac cause of dyspnea. HYPOTHESIS: Circulating concentrations of atrial natriuretic peptide (NT-proANP), B-type natriuretic peptide (BNP), endothelin-I (ET-1), and cardiac troponin-I (cTnI) can be used to help distinguish between cardiac and noncardiac causes of dyspnea in dogs. ANIMALS: Forty-eight client-owned dogs admitted to a veterinary teaching hospital for respiratory distress. METHODS: Blood samples from patients were prospectively obtained. The etiology of dyspnea was determined by using physical examination, thoracic radiographs, and echocardiography. RESULTS: CHF was diagnosed in 22 dogs, and dyspnea of noncardiac origin (noHD group) was diagnosed in 26 dogs. Analyses revealed significant difference between groups for NT-proANP (geometric mean, 95% confidence [CI]; no HD: 0.26 nmol/mL, 95% CI 0.17-1.09; CHF: 1.38 nmol/mL, 95% CI 1.09-1.74 nmol/mL; P < .0001), BNP (noHD: 12.18 pg/mL, 95% CI 10.91-16.17 pg/mL; CHF: 34.97 pg/mL, 95% CI 23.51-52.02 pg/mL; P < .0001), and ET-1 (noHD: 0.32 fmol/mL, 95% CI 0.23-0.46 fmol/mL; CHF: 1.26 fmol/mL, 95% CI 0.83-1.91 fmol/mL; P < .0001). Plasma cTnI concentrations were not significantly different between groups (noHD: 0.29 ng/mL, 95% CI 0.12-0.72 ng/mL; CHF: 0.42 ng/mL, 95% CI 0.18-0.97, P = .53). Receiver operating curves indicated areas under the curve for NT-proANP, BNP, and ET-1 of 0.946, 0.886, and 0.849, respectively. CONCLUSIONS AND CLINICAL IMPORTANCE: Plasma NT-proANP, BNP, and ET-1, but not cTnI, appear useful for distinguishing between dogs with cardiac and noncardiac causes of dyspnea, with plasma NT-proANP having the highest sensitivity (95.5%) and specificity (84.6%).

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OBJECTIVE: To determine ECG and echocardiographic measurements in healthy anesthetized Grevy's zebras (Equus grevyi). ANIMALS: 20 healthy zebras. PROCEDURES: Auscultation, base-apex ECG, and echocardiography were performed on anesthetized zebras. RESULTS: Low-grade systolic murmurs were detected in the left basilar region in 4 of 20 zebras. Evaluation of ECGs from 19 zebras revealed sinus rhythm with a predominantly negative QRS complex and a mean +/- SD heart rate of 67 +/- 10 beats/min. Echocardiograms of sufficient image quality were obtained for 16 zebras. Interventricular septal thickness in diastole, left ventricular chamber in diastole and systole, left atrial diameter, and left ventricular mass were significantly and moderately correlated with estimated body weight (r values ranged from 0.650 to 0.884). Detectable swirling of blood in the right and sometimes the left ventricles was detected in 9 of 16 zebras, whereas physiologic regurgitation of blood was detected for the aortic valve in 3 zebras, pulmonary valve in 2 zebras, mitral valve in 2 zebras, and tricuspid valve in 1 zebra. CONCLUSIONS AND CLINICAL RELEVANCE: Results of this study provide reference information for use in the cardiac evaluation of anesthetized Grevy's zebras.

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BACKGROUND: Dilated cardiomyopathy (DCM) is characterized by reduced systolic function, heightened sympathetic tone, and high morbidity and mortality. Little is known regarding the safety and efficacy of beta-blocker treatment in dogs with DCM. HYPOTHESIS: Carvedilol improves echocardiographic and neurohormonal variables in dogs with DCM over a 4-month treatment period. METHODS: Prospective, placebo-controlled, double-blinded randomized study. Dogs with DCM underwent echocardiography, ECG, thoracic radiographs, and neurohormonal profiling, followed by titration onto carvedilol (0.3 mg/kg q12h) or placebo over a 4-week period and subsequently received 3 months of therapy. Primary study endpoints included left ventricular volume and function. RESULTS: Sixteen dogs received carvedilol and 7 received placebo. At study end, 13 carvedilol dogs and 5 placebo dogs were alive. There was no difference in the mean percentage change in left ventricular volume at end-diastole (LVVd), left ventricular end-systolic volume (LVVs), and ejection fraction (EF) between treatment groups, suggesting that both groups experienced similar amounts of disease progression. Carvedilol treatment did not result in significant changes in neurohormonal activation, radiographic heart size, heart rate, or owner perceived quality-of-life. Baseline B-type natriuretic peptide (BNP) predicted dogs in the carvedilol-treated group that maintained or improved their EF over the study duration. CONCLUSIONS AND CLINICAL IMPORTANCE: Carvedilol administration did not improve echocardiographic or neurohormonal indicators of heart function. The lack of effect may be related to severity of disease, carvedilol dose, or brevity of follow-up time. Statistical power of the present study was adversely affected by a high fatality rate in study dogs and small sample size.

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OBJECTIVE: To map canine mitochondrial proteins and identify qualitative and quantitative differences in heart mitochondrial protein expression between healthy dogs and dogs with naturally occurring and induced dilated cardiomyopathy (DCM). SAMPLE POPULATION: Left ventricle samples were obtained from 7 healthy dogs, 7 Doberman Pinschers with naturally occurring DCM, and 7 dogs with induced DCM. PROCEDURES: Fresh and frozen mitochondrial fractions were isolated from the left ventricular free wall and analyzed by 2-dimensional electrophoresis. Protein spots that increased or decreased in density by >or= 2-fold between groups were analyzed by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry or quadrupole selecting, quadrupole collision cell, time-of-flight mass spectrometry. RESULTS: Within narrow pH gradients of control canine heart mitochondrial samples, a total of 1,528 protein spots were revealed. Forty subunits of heart mitochondrial proteins that differ significantly from control tissues were altered in tissue specimens from dogs with naturally occurring and induced forms of DCM. The most affected heart mitochondrial proteins in both groups were those of oxidative phosphorylation (55%). Upregulation of manganese superoxide dismutase was suggestive of heart oxidative injury in tissue specimens from dogs with both forms of DCM. Evidence of apoptosis was associated with overexpression of the heart mitochondrial voltage-dependent anion channel-2 protein and endonuclease G in tissue specimens from dogs with induced DCM. CONCLUSIONS AND CLINICAL RELEVANCE: Alterations of heart mitochondrial proteins related to oxidative phosphorylation dysfunction were more prevalent in tissue specimens from dogs with induced or naturally occurring DCM, compared with those of control dogs.

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OBJECTIVE: To identify qualitative and quantitative differences in cardiac mitochondrial protein expression in complexes I to V between healthy dogs and dogs with natural or induced dilated cardiomyopathy (DCM). SAMPLE POPULATION: Left ventricle samples were obtained from 7 healthy dogs, 7 Doberman Pinschers with naturally occurring DCM, and 7 dogs with DCM induced by rapid right ventricular pacing. PROCEDURES: Fresh and frozen mitochondrial fractions were isolated from the left ventricular free wall and analyzed by 2-dimensional electrophoresis. Protein spots that increased or decreased in density by 2-fold or greater between groups were analyzed by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry or quadrupole selecting, quadrupole collision cell, time-of-flight mass spectrometry. RESULTS: A total of 22 altered mitochondrial proteins were identified in complexes I to V. Ten and 12 were found in complex I and complexes II to V, respectively. Five were mitochondrial encoded, and 17 were nuclear encoded. Most altered mitochondrial proteins in tissue specimens from dogs with naturally occurring DCM were associated with complexes I and V, whereas in tissue specimens from dogs subjected to rapid ventricular pacing, complexes I and IV were more affected. In the experimentally induced form of DCM, only nuclear-encoded subunits were changed in complex I. In both disease groups, the 22-kd subunit was downregulated. CONCLUSIONS AND CLINICAL RELEVANCE: Natural and induced forms of DCM resulted in altered mitochondrial protein expression in complexes I to V. However, subcellular differences between the experimental and naturally occurring forms of DCM may exist.

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Esophageal talkers may have reduced intelligibility due to both time domain and frequency domain variability. The unpredictable nature of esophageal speech can cause problems when automatic procedures are used in applications such as long-distance telephone messages. The current study compared a standard coding algorithm (LPC-10e) with a novel approach to determining voiced periods (vocal tract area functions) in the speech of esophageal talkers. The results of the study showed that the sentences synthesized with the vocal tract area function algorithm were more intelligible than those synthesized with the standard LPC-10e algorithm. Supplemental information, such as vocal tract area functions, may be useful in determining voiced epochs when variability in vocal parameters is high.

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