Ayerza Syndrome

Ayerza syndrome (AS) describes the signs of pulmonary (arterial) hypertension [1]. It is mostly diagnosed in adults and has a higher prevalence in females than males. Defined by a mean pulmonary artery pressure of more than or equal to 25 mmHg and a capillary wedge pressure of over 15 mmHg [2], this medical entity can arise from a number of pathologies that may be cardiac or pulmonary in origin, or related to other systemic diseases, drugs, and toxins. Conditions that precipitate AS include chronic obstructive pulmonary disease (COPD), interstitial lung disease and fibrosis, left heart failure, autoimmune diseases and human immunodeficiency virus (HIV) infection. A significant proportion of cases are idiopathic, with no apparent cause, of which 70% have a mutation in the bone morphogenetic protein receptor type 2 (BMPR2) gene [3] [4] and few have in other genes, for example, activin receptor-like kinase type 1 (ACVRL1). Up to 40% of those with no family history of pulmonary hypertension (PH) also carry the gene mutation [5]. PH is progressive and may lead to death, especially if left untreated. Patients typically experience an insidious onset of symptoms that initially occur during exercise, and worsen as the ailment progresses. Consequently, this causes a delay in presentation and diagnosis. Early signs include dyspnea, syncope, dizziness, and cough [6]. Late manifestations are usually due to the underlying or resultant cardiac dysfunction and venous congestion. Among those reported are angina, hyperactive precordium, paroxysmal nocturnal dyspnea, hemoptysis, raised jugular venous pressure, abnormal heart sounds, and edema. Less common complaints include signs of liver failure such as ascites, and digital clubbing, which appear in an advanced stage.

Diagnosis and investigation of AS involve a plethora of invasive and non-invasive techniques. These are done in order to gauge the presence of an underlying pathology as well as to plan treatment and map prognosis based on the severity of symptoms [7]. The diagnostic test for AS is right heart catheterization, as it allows direct measurement of the pulmonary arterial pressure (which will be above 25 mmHg) and thus confirms the condition. Pulmonary capillary wedge pressure may be within the normal range.

Laboratory examination includes full blood count, assessment of liver, thyroid and renal function, immunological assays, arterial blood gas analysis (ABGA), and human immunodeficiency virus (HIV) testing [8]. Cardiac biomarkers such as brain natriuretic peptide (BNP) may be raised, indicating heart abnormalities [9].
Imaging may involve:

• Electrocardiogram (ECG): Shows signs of ventricular hypertrophy.
• Echocardiogram.
• Spirometry, ventilation-perfusion (V/Q) scanning, and pulmonary angiography to measure lung function.
• Administration of vasodilators to provoke a dilation of the pulmonary vessels, such as nitric oxide and adenosine, as well as other tests for staging and treatment planning [10].
• Chest X-ray: Shows increased lung perfusion as well as enlarged pulmonary vessels.
• Computerized tomography: Useful in chronic thromboembolic pulmonary arterial hypertension.
• Magnetic resonance imaging (MRI).

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3. Deng Z, Morse JH, Slager SL, et al. Familial primary pulmonary hypertension (gene PPH1) is caused by mutations in the bone morphogenetic protein receptor-II gene. Am J Hum Genet. 2000;67(3):737–744.
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5. Machado RD, Aldred MA, James V, et al. Mutations of the TGF-beta type II receptor BMPR2 in pulmonary arterial hypertension. Hum Mutat. 2006;27(2):121–132.
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8. Raymond R, Hinderliter A, Willis P, et al. Echocardiographic predictors of adverse outcomes in primary pulmonary hypertension. J Am Coll Cardiol. 2002;39(7):1214–1219.
9. Torbicki A, Kurzyna M, Kuca P, et al. Detectable serum cardiac troponin T as a marker of poor prognosis among patients with chronic precapillary pulmonary hypertension. Circulation. 2003;108(7):844–848.
10. Enright PL, McBurnie MA, Bittner V, et al. The 6-minute walk test: A quick measure of functional status in elderly adults. Chest. 2003;123(2):387-398.