Prevalence and Prognostic Importance of Pulmonary Hypertension in Dogs with Myxomatous Mitral Valve Disease

Abstract

Background: Pulmonary hypertension (PH) is common in dogs with myxomatous mitral valve disease (MMVD) but its effect on clinical outcome has not been investigated.Hypothesis/objectives: The presence of PH worsens the outcome in dogs with MMVD. To compare survival times of dogs with MMVD and PH to those without PH.Animals: Two hundred and twelve client-owned dogs. Methods: Case review study. Medical records of dogs diagnosed with ACVIM stage B2 and C MMVD between January 2010 and December 2011 were retrospectively reviewed. Long-term outcome was determined by telephone interview or from the medical record. End of the observation period was March 2013. PH was identified if tricuspid regurgitation peak velocity was >3 m/s.Results: Two hundred and twelve were identified. Eighty-three dogs (39%) had PH. PH was more commonly identified in stage C compared to B2 (P < .0001). One hundred and five (49.5%) dogs died during the observation period. Median survival time for the entire study population was 567 days (95% CI 512-743). Stage C (P = .003), the presence of PH (P = .009), left atrial to aortic root ratio (LA/Ao) >1.7 (P = .0002), normalized left-ventricular end-diastolic diameter (LVEDn) >1.73 (P = .048), and tricuspid regurgitation pressure gradient (TRPG) >55 mmHg (P = .009) were associated with worse outcomes in the univariate analyses. The presence of TRPG >55 mmHg (HR 1.8 95% CI 1-2.9; P = .05) and LA/ Ao > 1.7 (HR 2 95% CI 1.2-3.4; P = .01) remained significant predictors of worse outcome in the multivariate analysis.Conclusions and Clinical Importance: In dogs with MMVD, moderate to severe PH worsens outcome.

A prospective, randomized, double‐blind, placebo‐controlled pilot study of sacubitril/valsartan (Entresto) in dogs with cardiomegaly secondary to myxomatous mitral valve disease

“…There was no difference in the median RV : RA PG between groups at day 0 ( P  = .5243). Using a cut‐off RV : RA PG of ≥ 36 mm Hg (TR V max of 3.0 m/sec) for the diagnosis of PH,37 2 dogs in the S/V group and 3 dogs in the placebo group had mild PH, with none of the dogs having an RV : RA PG > 50 mm Hg.…”

Diagnostic Value of Right Pulmonary Artery Distensibility Index in Dogs with Pulmonary Hypertension: Comparison with Doppler Echocardiographic Estimates of Pulmonary Arterial Pressure

“…Pulmonary hypertension is commonly encountered in dogs affected with myxomatous mitral valve disease (MMVD), thromboembolic disease, parasitic disease (e.g, dirofilariasis, angiostrongyliasis), congenital cardiac shunts and various respiratory diseases 1, 2, 3, 4, 5, 6, 7. It adversely affects the quality of life and exercise tolerance and can cause syncope,4, 8 frequently influences diagnostic and therapeutic decisions,7 and is associated with a worse outcome in dogs with MMVD 2. Thus, screening for PH is an important part of the diagnostic evaluation in dogs exhibiting clinical signs of PH such as syncope, or affected with diseases commonly associated with PH.…”

Pulmonary Hypertension in the Dog

“…This condition is the most frequently observed cause of PH in dogs and is secondary to increased left atrial pressure and left heart failure [19] occurring with myxomatous mitral valve disease (MMVD), dilated cardiomyopathy (DCM), myocarditis and atrial distension associated with atrial 3 fi brillation [9,14,20]. In dogs with MMVD, the severity of PH is correlated with the progression of the disease, increased left atrial pressure [21][22][23] and an increased risk of death [23]. …”