ASSA13-17-2 The Acute Hemodynamic Responses of Pulmonary Arterial Hypertension Associated with Congenital Heart Disease to Iloprost

Abstract

<h3>Background</h3> Pulmonary arterial hypertension (PAH) is the commonest complication of left-to-right shunt congenital heart disease (CHD). Detection of pulmonary vascular reactivity is important for the evaluation of patient with PAH. <h3>Objective</h3> This study aimed to investigate the acute hemodynamic responses to iloprost in patients with idiopathic PAH (IPAH) and PAH associated with systemic-to–pulmonary shunt CHD (PAH-CHD). <h3>Methods</h3> This study included a cohort of patients with IPAH and PAH-CHD. The inclusion criteria were: ➀ IPAH with pulmonary artery systolic pressure &gt; 70mmHg measured by catheter and ➁ PAH-CHD with pulmonary artery systolic pressure &gt; 70mmHg and pulmonary-to-systemic flow ratio (Qp/Qs) &lt;1.5. After determination of baseline haemodynamic parameters by cardiac catheterization, 10μg of aerosol iloprost was inhaled and right heart catheterization was repeated. <h3>Results</h3> A total of 165 patients (118 females) aged 29 ± 13 years were recruited, including 24 with IPAH and 141 with PAH-CHD. There were 2 acute positive responders (8.3%) in patients with IPAH who benefited from the treatment of calcium antagonist thereafter. No positive responder was found in patients with PAH-CHD. Inhalation of aerosol iloprost induced significant decrease in pulmonary artery pressure (<i>P</i> &gt; 0.01), pulmonary vascular resistance (<i>P</i> &lt; 0.01) and pulmonary-to-systemic vascular resistance ratio (<i>P</i> &lt; 0.05) in patients with both IPAH and PAH-CHD. However, significant increase in oxygen saturation of femoral blood was only observed in patient with PAH-CHD. A ≥10% decrease in both pulmonary vascular resistance and pulmonary-to-systemic vascular resistance ratio at the end of drug exposure was observed in 58.9% of patients with PAH-CHD had but only in 45.8% of patients with IPAH. <h3>Conclusions</h3> There are 8.3% of acute positive responders in patients with IPAH but no positive response in patients with PAH-CHD. Although iloprost induces decrease in pulmonary artery pressure and pulmonary vascular resistance in patients with patients with IPAH and PAH-CHD, the acute hemodanamic changes were different.