Pulmonary hypertension

From Dog

Pulmonary hypertension is a common symptom of cardiovascular, renal and congenital disease.

Most cases in dogs are categorized as precapillary or postcapillary[1], which influences their diagnosis and treatment.

Pulmonary hypertension usually occurs as a result of endarteritis, resulting in narrowing of pulmonary arteries. Secondary complications of pulmonary hypertension include thromboembolism, pneumonitis, pneumonia and pulmonary effusion. As the disease progresses, intravascular pressure overload occurs in the right heart, leading to cor pulmonale, hepatomegaly and ascites.

Causes include:

Although mild hypertension may be subclinical, severe hypertension will result in varying degrees of dyspnea, coughing and occasionally, epistaxis, due to pulmonary infarcts.

Diagnosis is based on presenting clinical signs, radiographs (which usually show right-sided cardiomegaly and distension of pulmonary arteries), ultrasonography[7], echocardiography, Doppler echocardiography and elevations in serum cardiac troponin, NT-proBNP and atrial natriuretic peptide levels[8].

Bronchoalveolar lavage may be required to eliminate other causes of pulmonary disease.

Treatment usually requires drugs such as pimobendan[9], benazepril or sildenafil[10].

Adjunct therapy with drugs such as aminophylline may assist resolution of clinical signs.

References

  1. Kellihan HB & Stepien RL (2010) Pulmonary hypertension in dogs: diagnosis and therapy. Vet Clin North Am Small Anim Pract 40(4):623-641
  2. Chanoit G et al (2012) Surgical treatment of a pulmonary artery vascular hamartoma in a dog. J Am Vet Med Assoc 240(7):858-862
  3. Locatelli C et al (2012) Pulmonary hypertension associated with Ehrlichia canis infection in a dog. Vet Rec 170(26):676
  4. Seibert RL et al (2010) Successful closure of left-to-right patent ductus arteriosus in three dogs with concurrent pulmonary hypertension. J Vet Cardiol 12(1):67-73
  5. Kellihan HB & Stepien RL (2012) Pulmonary hypertension in canine degenerative mitral valve disease. J Vet Cardiol 14(1):149-164
  6. Matos JM et al (2012) Recruitment of arteriovenous pulmonary shunts may attenuate the development of pulmonary hypertension in dogs experimentally infected with Angiostrongylus vasorum. J Vet Cardiol 14(2):313-322
  7. Dell'Italia LJ (2012) Anatomy and physiology of the right ventricle. Cardiol Clin 30(2):167-187
  8. Hori Y et al (2012) Diagnostic utility of NT-proBNP and ANP in a canine model of chronic embolic pulmonary hypertension. Vet J 194(2):215-221
  9. Helms SR et al (2012) Compounded pimobendan for canine chronic degenerative mitral valve disease and pulmonary hypertension. Int J Pharm Compd 16(1):34-41
  10. Dias-Junior CA et al (2010) Hemodynamic effects of inducible nitric oxide synthase inhibition combined with sildenafil during acute pulmonary embolism. Nitric Oxide 23(4):284-288