Table 1.
Characteristics of 42 dogs with advanced myxomatous mitral valve disease.
| Characteristic/Group | With a History of Syncope | Without a History of Syncope |
|---|---|---|
| N | 20 | 22 |
| CKCS, n | 6 | 10 |
| Sex, female/male | 7/13 | 7/15 |
| Age, years (n = 20 + 22) | 11.2 ± 2.0 | 11.3 ± 2.3 |
| Body weight, kg (n = 18 + 22) | 8.3 ± 1.9 | 9.5 ± 2.7 |
| Systolic blood pressure, mmHg (n = 5 + 7) | 145.0 ± 34.8 | 150.4 ± 16.4 |
| Diastolic blood pressure, mmHg (n = 5 + 7) | 78.0 ± 7.0 | 78.4 ± 5.7 |
| IVSd, % (n = 15 + 19)a | 6.2 ± 25.0 | 11.7 ± 17.0 |
| IVSs, % (n = 15 + 19)a | 14.2 ± 17.7 | 11.5 ± 20.3 |
| LVIDd, % (n = 17 + 22) | 45.4 ± 15.2 | 39.0 ± 22.4 |
| LVIDs, % (n = 15 + 19) | 42.0 ± 27.0 | 29.2 ± 23.8 |
| LVPWd, % (n = 15 + 19) | 12.3 ± 16.4 | 16.2 ± 16.1 |
| LVPWs, % (n = 15 + 19)a | 3.0 ± 16.3 | ‐0.1 ± 13.2 |
| LA/Ao (n = 17 + 22) | 2.2 ± 0.3 | 2.0 ± 0.5 |
| PISA, mm (n = 13 + 22) | 13.3 ± 6.0 | 14.1 ± 5.1 |
| FS, % (n = 15 + 19) | 36.8 ± 8.7 | 38.8 ± 5,2 |
| TR, no/mild/moderate/severe (n = 10 + 19) | 0/7/1/2 | 4/8/4/3 |
| peak TR velocity, m/s (n = 12 + 8) | 3.3 ± 1.0 | 3.3 ± 0.7 |
| PAH, normal/equivocal/hypertensive (n = 12 + 8)b | 1/4/7 | 0/1/7 |
Values are shown as mean ± SD. Characteristic is suffixed by (n, number of dogs with a history of syncope + number of dogs without a history of syncope). In addition to CKCS, dogs with a history of syncope comprised 3 Dachshunds, 2 Jack Russell Terriers, 2 Pekingeses, 1 King Charles Spaniel, 1 Maltese, 1 Miniature Poodle, 1 Chinese Chrested, 1 Bichon Frisé, 1 Bichon Havanais, and a mixed breed dog. Dogs without a history of syncope in addition to CKCS comprised 3 Dachshunds, 2 Jack Russell Terriers, 1 King Charles Spaniel, 1 Maltese, 2 Norfolk Terriers, 1 Bichon Frisé, 1 Boston Terrier, and 1 Bedlington Terrier. Using a Student's t‐test, none of the characteristics was significantly different between dogs with and without a history of syncope.
CKCS, Cavalier King Charles Spaniel; d, diastole; FS, fraction shortening; IVS, percentage increase in interventricular septal thickness; LA/Ao, left atrium‐to‐aortic root ratio; LVID, percentage increase in left ventricular internal dimension; LVPW, percentage increase in left ventricular free wall thickness; PAH, pulmonary hypertension; PISA, proximal isovelocity surface area; TR, tricuspid regurgitation; s, systole.
Variable was logarithmic transformed to obtain normal distribution.
PAH is categorized according to peak TR velocity (normal <2.5 m/s, equivocal 2.5–3.0 m/s, and hypertensive >3.0 m/s).50