J Vet Sci.  2017 Sep;18(3):369-376. 10.4142/jvs.2017.18.3.369.

Retrospective study of degenerative mitral valve disease in small-breed dogs: survival and prognostic variables

• Kim HT
• Han SM
• Song WJ
• Kim B
• Choi M
• Yoon J
• Youn HY

• KMID: 2412455
• DOI: http://doi.org/10.4142/jvs.2017.18.3.369

Abstract

Small-breed dogs (n = 168; weight < 15 kg) diagnosed with myxomatous mitral valve degeneration based on a routine clinical examination, radiology, electrocardiography, and echocardiography at the Seoul National University Veterinary Medical Teaching Hospital were included in this study. Survival periods were determined, and there were significant differences in survival rates among the three International Small Animal Cardiac Health Council classes. The mean follow-up period was 14.3 ± 12.1 months. Univariate analysis revealed that dyspnea, pulmonary edema, and vertebral heart score were significantly associated with survival time (p < 0.05). Additionally, age, left atrial-to-aortic root ratio, ejection fraction, and left ventricular end diastolic volume were associated with an increased risk of death (p < 0.1), while body weight, body condition score, systolic blood pressure, arrhythmia, syncope, fractional shortening, and end systolic volume were not associated with an increased risk of death. These results suggest that among the assessed variables dyspnea, pulmonary edema, and vertebral heart score could be useful prognostic factors for providing patient information to owners.

Keyword

congestive heart failure; mitral valve disease; prognosis; survival rate; vertebral heart score

MeSH Terms

Animals
Dog Diseases/*diagnosis/mortality/pathology
Dogs
Echocardiography/veterinary
Female
Male
Mitral Valve Insufficiency/diagnosis/mortality/pathology/*veterinary
Prognosis
Radiography/veterinary
Retrospective Studies
Survival Analysis

Figure

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  Fig. 1 Survival of 168 dogs classified according to International Small Animal Cardiac Health Council (ISACHC) criteria. One-hundred-fifteen of the 168 dogs died during the observation period. Nineteen dogs were ISACHC class I, 47 dogs were ISACHC class II, and 49 dogs were ISACHC class III at initial examination. Survival duration of the ISACHC class I dogs (mean survival time: 461 ± 322 days) was higher than those of the dogs in classes II and III (274 ± 289 days and 376 ± 315 days, respectively).

Reference

1. Boon JA. Evaluation of size, function, and hemodynamics. Manual of Veterinary Echocardiography. Chichester: Wiley;1998. p. 153–266.

2. Borgarelli M, Savarino P, Crosara S, Santilli RA, Chiavegato D, Poggi M, Bellino C, La Rosa G, Zanatta R, Haggstrom J, Tarducci A. Survival characteristics and prognostic variables of dogs with mitral regurgitation attributable to myxomatous valve disease. J Vet Intern Med. 2008; 22:120–128.

3. Buchanan JW. Vertebral scale system to measure heart size in radiographs. Vet Clin North Am Small Anim Pract. 2000; 30:379–393.

4. Disatian S. Myxomatous degenerative mitral valve disease: an update. Thail J Vet Med. 2010; 40:151–157.

5. Guglielmini C, Diana A, Pietra M, Di Tommaso M, Cipone M. Use of the vertebral heart score in coughing dogs with chronic degenerative mitral valve disease. J Vet Med Sci. 2009; 71:9–13.

6. Häggström J, Boswood A, O'Grady M, Jöns O, Smith S, Swift S, Borgarelli M, Gavaghan B, Kresken JG, Patteson M, Ablad B, Bussadori CM, Glaus T, Kovacević A, Rapp M, Santilli RA, Tidholm A, Eriksson A, Belanger MC, Deinert M, Little CJ, Kvart C, French A, Rønn-Landbo M, Wess G, Eggertsdottir AV, O'Sullivan ML, Schneider M, Lombard CW, Dukes-McEwan J, Willis R, Louvet A, DiFruscia R. Effect of pimobendan or benazepril hydrochloride on survival times in dogs with congestive heart failure caused by naturally occurring myxomatous mitral valve disease: the QUEST study. J Vet Intern Med. 2008; 22:1124–1135.

7. Häggström J, Kvart C, Pedersen H. Acquired valvular heart disease. In : Ettinger SJ, Feldman EC, editors. Textbook of Veterinary Internal Medicine: Diseases of the Dog and Cat. 6th ed. Oxford: Elsevier Saunders;2005. p. 1022–1039. .

8. Hansson K, Häggström J, Kvart C, Lord P. Left atrial to aortic root indices using two-dimensional and M-mode echocardiography in cavalier King Charles spaniels with and without left atrial enlargement. Vet Radiol Ultrasound. 2002; 43:568–575.

9. Lamb CR, Tyler M, Boswood A, Skelly BJ, Cain M. Assessment of the value of the vertebral heart scale in the radiographic diagnosis of cardiac disease in dogs. Vet Rec. 2000; 146:687–690.

10. Nelson RW, Couto CG. Cardiovascular system disorders. Small Animal Internal Medicine. 5th ed. St. Louis: Elsevier;2014. p. 1–216.

11. Parker HG, Kilroy-Glynn P. Myxomatous mitral valve disease in dogs: does size matter? J Vet Cardiol. 2012; 14:19–29.

12. Sahn DJ, DeMaria A, Kisslo J, Weyman A. Recommendations regarding quantitation in M-mode echocardiography: results of a survey of echocardiographic measurements. Circulation. 1978; 58:1072–1083.

13. Serres FJ, Chetboul V, Tissier R, Carlos Sampedrano C, Gouni V, Nicolle AP, Pouchelon JL. Doppler echocardiography-derived evidence of pulmonary arterial hypertension in dogs with degenerative mitral valve disease: 86 cases (2001–2005). J Am Vet Med Assoc. 2006; 229:1772–1778.

14. Simpson KE, Devine BC, Gunn-Moore DA, French AT, Dukes-McEwan J, Koffas H, Moran CM, Corcoran BM. Assessment of the repeatability of feline echocardiography using conventional echocardiography and spectral pulse-wave Doppler tissue imaging techniques. Vet Radiol Ultrasound. 2007; 48:58–68.

15. Smith PJ, French AT, Van Israël N, Smith SGW, Swift ST, Lee AJ, Corcoran BM, Dukes-McEwan J. Efficacy and safety of pimobendan in canine heart failure caused by myxomatous mitral valve disease. J Small Anim Pract. 2005; 46:121–130.

16. Teichholz LE, Kreulen T, Herman MV, Gorlin R. Problems in echocardiographic volume determinations: echocardiographic-angiographic correlations in the presence or absence of asynergy. Am J Cardiol. 1976; 3:7–11.

17. The BENCH (BENazepril in Canine Heart disease) Study Group. The effect of benazepril on survival times and clinical signs of dogs with congestive heart failure: results of a multicenter, prospective, randomized, double-blinded, placebo-controlled, long-term clinical trial. J Vet Cardiol. 1999; 1:7–18.

18. Thomas WP, Gaber CE, Jacobs GJ, Kaplan PM, Lombard CW, Moise NS, Moses BL. Echocardiography Committee of the Specialty of Cardiology. American College of Veterinary Internal Medicine. Recommendations for standards in transthoracic two-dimensional echocardiography in the dog and cat. J Vet Intern Med. 1993; 7:247–252.