Prevalence of mitral valve regurgitation in 79 asymptomatic Norfolk terriers.

OBJECTIVES: To determine the prevalence of mitral valve regurgitation (MR) in asymptomatic Swedish Norfolk terriers. ANIMALS: Seventy-nine privately owned Norfolk terriers. MATERIALS AND METHODS: A prospective observational study was conducted where dogs were recruited via the Swedish Norfolk terrier club. All dogs were examined using the same protocol including physical examination and Doppler echocardiography. RESULTS: Fifteen dogs (19%) had a murmur at the time of the examination. A total of 35 dogs (44%) had MR, including 23 dogs (29%) with both MR and tricuspid valve regurgitation and 12 dogs (15%) with MR only, identified on Doppler echocardiography. In addition, 7 dogs (9%) had tricuspid valve regurgitation only. The prevalence of MR increased with increasing age (p < 0.0001). CONCLUSIONS: Mitral valve regurgitation is common in asymptomatic Norfolk terriers with and without murmurs and the prevalence increases with age. The impact of MR in this breed on survival remains to be elucidated by a longitudinal study.

Real-Time 3-Dimensional Echocardiographic Assessment of Effective Regurgitant Orifice Area in Dogs With Myxomatous Mitral Valve Disease.

BACKGROUND: Effective regurgitant orifice area (EROA), calculated from the vena contracta width (VCW) as the narrowest portion of the proximal regurgitant jet, might be used to estimate severity of mitral regurgitation. However, this simplified assumption only holds when the EROA is circular, which might not be true in dogs with myxomatous mitral valve disease (MMVD). HYPOTHESIS: Effective regurgitant orifice area in dogs with MMVD is noncircular, and using color Doppler real-time 3-dimensional (RT3D) echocardiography, measured EROA in the en face view will be significantly different from calculated EROA. ANIMALS: Hundred and fifty-eight privately owned dogs with naturally occurring MMVD. MATERIALS AND METHODS: Prospective observational study comparing en face view of EROA with calculated EROA using VCW in 4-chamber (4Ch) and 2-chamber (2Ch) view only or combined 4Ch and 2Ch views using RT3D echocardiography. RESULTS: The calculated EROA using the 2Ch view showed a systematic underestimation of 17% compared with the measured en face EROA corrected for body surface area. The calculated EROA using 4Ch and 4Ch + 2Ch views showed less agreement with the en face EROA, and the difference between methods increased with increasing EROA. The difference between calculated and measured EROA showed a systematic underestimation of the calculated EROA by 36% (4Ch) and 33% (4Ch + 2Ch), respectively, compared to measured en face EROA. CONCLUSION AND CLINICAL IMPORTANCE: When replacing measured EROA with calculated EROA using VCW measurements, the 2Ch view is preferred in dogs with MMVD.

Left atrial ejection fraction assessed by real-time 3-dimensional echocardiography in normal dogs and dogs with myxomatous mitral valve disease.

BACKGROUND: Real-time 3-dimensional (RT3D) echocardiography provides a novel technique for assessing left atrial ejection fraction (LAEF) in dogs. HYPOTHESIS: Left atrial ejection fraction is associated with severity of myxomatous mitral valve disease (MMVD). ANIMALS: Privately owned dogs; 101 with MMVD and 52 healthy control dogs. METHODS: Prospective observational study using RT3D echocardiographic estimations of LA volumes at atrial end-diastole and atrial end-systole to calculate LAEF in comparison with conventional 2-dimensional echocardiographic variables. RESULTS: Left atrial ejection fraction decreased with increasing LA to aortic ratio (LA/Ao), percentage increase in left ventricular (LV) internal dimension, corrected for body weight (BW), in diastole (LVIDd inc%) and systole (LVIDs inc%), and age for MMVD dogs, and with BW for control dogs. The final models in the multiple regression analyses included LVIDd inc% and age for MMVD dogs, and BW alone for control dogs. LAEF varied widely in both MMVD dogs and control dogs. CONCLUSION AND CLINICAL IMPORTANCE: The wide variation of LAEF and the fact that LAEF does not appear to be an independent marker of disease severity suggest that the clinical importance of determining LAEF in dogs with MMVD might be limited.

Comparisons of 2- and 3-dimensional echocardiographic methods for estimation of left atrial size in dogs with and without myxomatous mitral valve disease.

BACKGROUND: Two-dimensional (2D) and real-time three-dimensional (RT3D) echocardiography can be used to assess left atrial (LA) size, but their correlation in dogs remains unknown. HYPOTHESIS: Estimations of LA size differ depending on the echocardiographic technique. ANIMALS: Privately owned dogs; 70 with myxomatous mitral valve disease and 32 healthy control dogs. METHODS: Prospective observational study comparing RT3D volume at atrial end-diastole (RT3DLAd) with 4 different 2D methods of estimating LA size: LA diameter and area in short-axis (LA(sax) and LA(area)) and LA diameter in long-axis (LA(lax)), both as indexed variables and as predictors of LA volume indexed to body weight (BW) using allometric scaling and geometric assumption of sphericity. Furthermore, agreement between indexed 2D based methods was studied using concordance correlation coefficient (ρ(c)) and Bland-Altman plots. RESULTS: None of the indexed 2D methods of estimating LA size showed good correlation with BW-indexed RT3DLAd volumes. Estimates of LA volumes from 2D measurements using allometric scaling showed better correlation with RT3D volumes than corresponding calculated volume approximations. The best correlation was found between RT3DLAd and estimated LA volumes based on allometric scaling of LA(lax) (ρ(c) = 0.89) followed by LA(area) (ρ(c) = 0.86) measurements. Comparing indexed 2D-based measurements of LA size, best agreement was found between LA(sax) to aortic diameter and LA(sax) to expected LA diameter, based on allometric scaling. CONCLUSIONS AND CLINICAL IMPORTANCE: Allometric scaling of 2D-based measurements of LA showed good correlation with RT3DLAd, whereas corresponding indexed measurements or calculated volume approximations did not.

Comparisons of 3-, 2-dimensional, and M-mode echocardiographical methods for estimation of left chamber volumes in dogs with and without acquired heart disease.

BACKGROUND: Real-time 3-dimensional echocardiography (RT3D) is a recent technique based on volumetric scanning, eliminating the need for geometric modeling of the cardiac chambers and minimizing the errors caused by foreshortened views. HYPOTHESIS: Estimations of left ventricular (LV) end-diastolic (EDV) and end-systolic volume (ESV), and left atrial (LA) size, differ depending on the echocardiographic technique of estimation. ANIMALS: Fifty-one dogs with acquired heart disease and 34 healthy control dogs. METHODS: Prospective observational study by M-mode (Teichholz method), Simpson's modified 2-dimensional (2D) method, and RT3D methods for estimation of LV volumes. LA size was evaluated by 2D and RT3D methods. RESULTS: RT3D showed good agreement with 2D for EDV and ESV, whereas Teichholz method overestimated LV volumes in comparison with the other 2 methods by approximately a factor 2. There were no statistically significant differences among the 3 methods in estimating ejection fraction. Comparison between RT3D assessment of LA end-systolic volume per kilogram (LAs/kg) and LA to aortic ratio (LA/Ao) measured by 2D relative to each other showed that the RT3D method underestimated LAs/kg at lower values, and overestimated it at higher values. The difference between methods increased with increasing LA size. CONCLUSIONS AND CLINICAL IMPORTANCE: There was good agreement between RT3D and 2D methods of estimating EDV and ESV, whereas the Teichholz method overestimated LV volumes by approximately a factor 2. In comparison with RT3D, LA/Ao underestimated LA size, especially when LA was enlarged.

Tissue Doppler and strain imaging in dogs with myxomatous mitral valve disease in different stages of congestive heart failure.

BACKGROUND: Tissue Doppler imaging (TDI) including strain and strain rate (SR) assess systolic and diastolic myocardial function. HYPOTHESIS: TDI, strain, and SR variables of the left ventricle (LV) and the interventricular septum (IVS) differ significantly between dogs with myxomatous mitral valve disease (MMVD) with and without congestive heart failure (CHF). ANIMALS: Sixty-one dogs with MMVD with and without CHF. Ten healthy control dogs. METHODS: Prospective observational study. RESULTS: Radial motion: None of the systolic variables were altered and 3 of the diastolic velocities were significantly increased in dogs with CHF compared with dogs without CHF and control dogs. Longitudinal motion: 2 systolic velocities and 3 diastolic velocities were significantly increased in dogs with CHF compared with dogs without CHF and control dogs. Difference in systolic velocity time-to-peak between LV and IVS was significantly increased in dogs with MMVD with and without CHF compared with control dogs. In total, 11 (23%) of 48 TDI and strain variables differed significantly between groups. Left atrial to aortic ratio was positively correlated to early diastolic velocities, percentage increase in left ventricular internal diameter in systole was positively correlated to systolic and diastolic velocities, and mitral E wave to peak early diastolic velocity in the LV basal segment (E/Em) was positively correlated to radial strain and SR. CONCLUSIONS AND CLINICAL IMPORTANCE: Few TDI and strain variables were changed in dogs with MMVD with and without CHF. Intraventricular dyssynchrony may be an early sign of MMVD or may be an age-related finding.

Laparoscopic vs open Roux-en-Y gastric bypass: a prospective, randomized trial.

BACKGROUND: The feasibility of laparoscopic Roux-en-Y gastric bypass (Lap-RYGBP) for morbid obesity is well documented. In a prospective randomized trial, we compared laparoscopic and open surgery. METHODS: 51 patients (48 females, mean (+/- SD) age 36 +/- 9 years and BMI 42 +/- 4 kg/m2) were randomly allocated to either laparoscopy (n = 30) or open surgery (n = 21). All patients were followed for a minimum of 1 year. RESULTS: In the laparoscopy group, 7 patients (23%) were converted to open surgery due to various procedural difficulties. In an analysis, with the converted patients excluded, the morphine doses used postoperatively were significantly (p < 0.005) lower in the laparoscopic group compared to the open group. Likewise, postoperative hospital stay was shorter (4 vs 6 days, p < 0.025). Six patients in the laparoscopy group had to be re-operated due to Roux-limb obstruction in the mesocolic tunnel within 5 weeks. The weight loss expressed in decrease in mean BMI units after 1 year was 14 +/- 3 and 13 +/- 3 after laparoscopy and open surgery, respectively (not significant). CONCLUSIONS: Both laparoscopic and open RYGBP are effective and well received surgical procedures in morbid obesity. Reduced postoperative pain, shorter hospital stay and shorter sick-leave are obvious benefits of laparoscopy but conversions and/or reoperations in 1/4 of the patients indicate that Lap-RYGBP at present must be considered an investigational procedure.

Silicone-adjustable gastric banding: disappointing results.

BACKGROUND: Silicone-adjustable Gastric banding (SAGB) has been popularized as a minimally invasive, completely reversible surgical treatment for morbid obesity. We report here our 3-year experience of SAGB with special reference to complications and side-effects. METHODS: There were 90 patients in total, of whom 72 were women. Median age was 42 (range, 20-68) years and median body mass index (BMI) was 43 (range, 34-57) kg/m2. Laparoscopy was attempted to position the band in 63 cases but had to be converted to laparotomy in 16 (25%). Twenty-seven patients were laparotomized. We used the Swedish band (AB Obtech) throughout the series. In addition to regular clinic visits, patients were followed-up with upper gastrointestinal series 6 months postoperatively and gastroscopy after 2 years or earlier when symptomatic. RESULTS: Median BMI decreased to 32 kg/m2 after 12 months and to 31 kg/m2 after 24 months. With a median follow-up time of 35 months (range, 22-48), 32 patients (35%) have been re-operated usually with removal of the balloon system and conversion into a Roux-en-Y gastric bypass. The most common reasons for re-operation were band erosion (n = 10) and erosive esophagitis (n = 14). Additional indications for re-operation included pouch dilatation, invagination of distal gastric wall through the band, leakage from the balloon, patient dissatisfaction, and severe allergic reaction. When questioned 2 years postoperatively more than half of the patients reported vomiting, heartburn and regurgitation but 78% still pronounced themselves satisfied with the operation. Esophagitis was found in 56% of the patients at gastroscopy after 2 years. CONCLUSION: SAGB could be positioned with laparoscopy in 75% of the cases but the incidence of complications and side-effects postoperatively has been high.

Interrater agreement in oculo-kinetic perimetry--a screening test for glaucoma.

In a study at the Flinders Medical Centre, South Australia, 24 glaucomatous eyes with known field defects were tested by three examiners of different backgrounds using oculo-kinetic perimetry, a screening test for glaucoma. The interrater agreement was excellent; only in one case did results differ. Seventeen eyes had a defective result, but in six cases the test was normal. Both patients and untrained staff find this test easy to do, but the apparent high false-negative rate is cause for concern and needs further evaluation. Oculo-kinetic perimetry may well be better used as a complementary test by those opticians doing tonometry and by general practitioners who currently rarely screen for glaucoma.

Factors influencing the formation of posterior capsular opacities after extracapsular cataract extraction with posterior chamber lens implant.

This study was designed to determine whether different factors could influence the formation of posterior capsular opacities. The study group comprised 271 patients who had undergone an extracapsular cataract extraction with implantation of a posterior chamber lens either with or without laser ridge. Between 12 and 25 months after surgery, a statistically significant difference was found with a lower rate of secondary cataract in the laser ridge group, but with respect to advanced secondary cataract, i.e. eyes which needed YAG capsulotomy, no statistically significant difference was found (P-value 0.99). No association was found between age or sex of patients, different surgeons or complications during or after surgery and the risk of getting a secondary cataract.