Correlation of Radiographic, Echocardiographic, and Electrocardiographic Signs of Left Heart Enlargement in Dogs With Mitral Regurgitation

Abstract

Thoracic radiographs of 40 dogs with mitral regurgitation were evaluated for signs of left heart enlargement and classified into three groups based on the degree of left atrial enlargement (mild = group A, moderate = group B, and severe = group C). Echocardiographic enlargement ratios were calculated for the left atrium (LAEecho), the left ventricle (LVEecho), and the aorta (AOEecho) by dividing the measured dimension with the expected dimension normalized for body weight. The incidence of LVH patterns and p‐mitrale was recorded on electrocardiograms. With advanced stages of the disease, there was good agreement of the radiographs and echocardiograms with significant differences of the left atrial enlargement ratio between groups. Nine of the 16 dogs from groups A and B, however, had LAEecho ratios within the normal range. Sixteen dogs with radiographic signs of left ventricular enlargement had normal LVEecho ratios. These disagreements were interpreted as either cardiac enlargement not manifest in the dimensional change measured by the echocardiogram or as overreading of radiographs. The left ventricular wall thickness did not vary significantly between groups. The incidence of p‐mitrale was 30%, but this ECG abnormality, when present, reliably identified enlarged left atrial dimensions. Left ventricular hypertrophy patterns of the ECG did not correlate with either the radiographic diagnosis of left ventricular enlargement or the echocardiographic enlargement ratios.

Assessment of survey radiography as a method for diagnosis of congenital cardiac disease in dogs

“…In humans, survey radiography has an accuracy of about 70 per cent for diagnosis of cardiomegaly (Glover andothers 1973, Murphy andothers 1985); however, the accuracy for diagnosis of specific chamber enlargement is much lower (Murphy and others 1985). Similarly, previous studies of dogs with cardiac chamber enlargement have found only a fair correlation between 544 -JOURNAL OF S W ANIMAL PRACTICE VOL 42 NOVEMBER 2001 the results of echocardiography and radiography Ackerman 1984, Lombard andSpencer 1985). Recalculating the level of agreement in these studies results in a kappa of 0.24 for right ventricular size (in 54 heartworm-infected dogs, data in Lombard and Ackerman 1984) and a kappa of 0.14 for left ventricular enlargement (in 40 dogs with mitral regurgitation, data in Lombard and Spencer 1985).…”

Normal Electro‐ and Vectocardiographic Data in the Growing Friesian Calf Using a Semi‐Orthogonal Lead System

“…However, its use in this species is generally limited to study of the heart rate or cardiac arrhythmia. Vectocardiography is useful to assess the heart size and position in man (GUYTON, 1986; BERNE and LEVY, 1988) and small animals (ETTINGER and SUTER, 1970; LOMBARD and SPENCER, 1985;DETWEILER, 1984). In ungulates, the sensitivity of vectocardiography to detect such changes is lower because of a specific disposition of the Purkinje fibers ( SMITH et al, 1957;MUYLLE and OYAERT, 1977) and the diagnostic value of the technique is essentially unknown (PHYSICK-SHEARD, 1987).…”

Quantitative Echocardiographic Evaluation of Mitral Endocardiosis in Dogs Using Ratio Indices

“…Many of the echocardiographically detectable remodeling changes associated with chronic MR are well known and have been described qualitatively and semiquantitatively. 6,7 The current study recapitulates essential abnormalities known to occur with CVD/ MR, such as LA and ventricular dilatation (ie, increased wLA, wLVIDd) and recasts them into the body size-independent format of ERIs.…”