[Measuring myocardial velocity using tissue Doppler imaging in healthy dogs]. / Messung der myokardialen Geschwindigkeit mittels Gewebe-Doppler beim gesunden Hund.

OBJECTIVE: of the study was to evaluate tissue velocity imaging (TVI) with respect to its reproducibility and to introduce reference values in a large canine population. In addition, the influence of gender, heart rate, age, weight and breed of the dogs was evaluated. MATERIAL AND METHODS: A total of 199 healthy dogs were included. The longitudinal TVI was recorded from an apical four-chamber view using colour Doppler technique in unsedated dogs. Each myocardial wall was recorded as a single wall image, aligning the ultrasound beam as parallel as possible to the longitudinal motion of the respective wall. Off-line analysis was performed using the Q-analysis software. RESULTS: Coefficients of variance for intrareader and interreader variability for each parameter were less than 10.0% and 12.4%, respectively. Tissue velocities were heterogeneously distributed within the myocardium, demonstrating an apico-basal gradient. Whereas gender did not influence TVI variables, heart rate, age, breed and weight had a significant influence on the tissue velocity. CONCLUSION AND CLINICAL RELEVANCE: TVI is a sophisticated and promising echocardiographic technique. It is relatively easy to perform and can be included in the evaluation of systolic and diastolic myocardial function in routine daily practice. One limitation is that it is influenced by heart rate, age, breed and weight of the dogs. This study provides a basis for further investigation on this topic and supplies reference values for different weight groups in dogs.

Prevalence of dilated cardiomyopathy in Doberman Pinschers in various age groups.

BACKGROUND: Dilated cardiomyopathy (DCM) in Doberman Pinschers is an autosomal dominant inherited disease. The prevalence of DCM in Doberman Pinschers of various age groups in Europe is currently unknown, but this information would be important to develop recommendations for screening programs. OBJECTIVES: To evaluate the prevalence of cardiomyopathy in various age groups of Dobermans. ANIMALS: Seven hundred and seventy-five examinations in 412 Doberman Pinschers. METHODS: Dogs were included in a prospective longitudinal cohort study. Each examination included echocardiography and 24-hour ECG (Holter) examination. A cut-off value of >100 ventricular premature contractions (VPCs) per 24 hours on Holter examination or abnormal echocardiography was considered diagnostic for cardiomyopathy. The cumulative prevalence included all dogs with DCM and healthy dogs >7 years of age. RESULTS: DCM prevalence in various age groups was as follows: age group 1 (1 to <2 years) 3.3%, age group 2 (2 to <4 years) 9.9%, age group 3 (4 to <6 years) 12.5%, age group 4 (6 to <8 years) 43.6%, and age group 5 (>8 years) 44.1%. The cumulative prevalence of Doberman Pinscher cardiomyopathy was 58.2%. There was an equal sex distribution, but male dogs showed earlier echocardiographic changes than did female dogs, which had significantly more VPCs. CONCLUSIONS AND CLINICAL IMPORTANCE: The prevalence of Doberman cardiomyopathy is very high in Europe. Disease manifestation and progression are different between male and female dogs. Yearly screening for DCM by Holter examination and echocardiography is recommended, starting at 2 years of age.

Comparison of pulsed wave and color Doppler myocardial velocity imaging in healthy dogs.

BACKGROUND: Tissue velocity imaging (TVI) is increasingly used in small animal cardiology. Tissue velocity of the myocardial wall can be measured by pulsed wave (PW) or color Doppler (CD) imaging methods. Currently, the same reference ranges are used for PW TVI and CD TVI methods. However, if and how both methods correlate, and whether they can be used interchangeably, have not been assessed in small animals. OBJECTIVES: To compare the results of PW TVI and CD TVI measurements. ANIMALS: Seventy-one healthy dogs. METHODS: Longitudinal myocardial velocity profiles were recorded from the 4-chamber left apical view. Peak maximal systolic (S), early (E), and late diastolic (A) velocities were measured off-line in a blinded fashion in the septal and lateral left ventricular wall by PW TVI and CD TVI. Differences between peak PW TVI and CD TVI waves were analyzed by a paired t-test. Regression analysis and Bland-Altman difference plots also were used to assess agreement between methods. RESULTS: There was a significant correlation between PW TVI and CD TVI (P < .001). However, S, E, and A waves measured by PW TVI were significantly higher than the CD TVI values (P < .001). Peak systolic and diastolic PW velocities were approximately 2.20 cm/s higher than corresponding mean CD TVI velocities. CONCLUSIONS AND CLINICAL IMPORTANCE: PW TVI measurements are significantly higher compared with CD TVI measurements. Theses differences are clinically relevant. These methods should not be used interchangeably, and different reference ranges for PW TVI and CD TVI should be used.

Treatment of dogs with lymphoma using a 12-week, maintenance-free combination chemotherapy protocol.

BACKGROUND: Treatment of lymphoma in dogs by long-term chemotherapy has favorable results. However, the efficacy of short-term, maintenance-free treatment protocols on remission and survival times in dogs has not been determined. HYPOTHESIS: That treatment using a 12-week chemotherapy protocol would be associated with satisfactory treatment outcome in dogs with lymphoma. ANIMALS: 77 dogs with histologically or cytologically confirmed diagnosis of lymphoma. METHODS: Prospective clinical trial in which dogs were treated with a 12-week chemotherapy protocol consisting of L-asparaginase, vincristine, cyclophosphamide, doxorubicin, and prednisolone. RESULTS: Complete remission rate was 76.3%. Multivariate logistic regression analysis revealed that clinical substage (P = .006) and immunophenotype (P = .003) had a significant influence on the likelihood of a dog achieving complete remission. Median duration of first complete remission was 243 days (range 19-1,191 days). The 6-month, 1-year, and 2-year remission rates were 68%, 28%, and 16%, respectively. In the multivariate analysis of patient variables, immunophenotype (P = .022) revealed a significant influence on first remission duration. Toxicosis was mild with the exception of 1 treatment-associated death. CONCLUSIONS AND CLINICAL IMPORTANCE: In this group of dogs the 12-week maintenance-free chemotherapy protocol was well tolerated and had satisfactory results.