Cardiac catheterization in pulmonary hypertension: doing it right, with a catheter on the left

Comment on: Severe pulmonary hypertension in pulmonary alveolar microlithiasis: A comprehensive literature review

This letter commends the study "Severe pulmonary hypertension in pulmonary alveolar microlithiasis: A comprehensive literature review" for its thorough exploration of Pulmonary Alveolar Microlithiasis (PAM) and its association with pulmonary hypertension (PH). The study offers insights into PAM's genetics, clinical manifestations, diagnostic approaches, and treatment modalities. It highlights the importance of early diagnosis and management while discussing limitations such as its retrospective nature and small sample size. Despite these limitations, the study contributes significantly to understanding PAM and PH, emphasizing the need for larger prospective studies to validate findings and explore novel therapeutic avenues.

Case report: Rescue treatment with add-on selexipag in a preterm infant with suprasystemic pulmonary hypertension, pulmonary capillary hemangiomatosis, and isolated pulmonary vein stenosis

An extremely dystrophic, premature female infant, born at 25 3/7 weeks of gestational age (birth weight: 430 g) with severe pulmonary hypertension (PH), was admitted to our neonatal intensive care unit (ICU) requiring cardiorespiratory support, including mechanical ventilation and pulmonary vasodilators such as inhaled nitric oxide (iNO) and continuous intravenous sildenafil infusions. The diagnosis of bronchopulmonary dysplasia (BPD) was made. A hemodynamically relevant, persistent ductus arteriosus (PDA) was surgically ligated after failed pharmacologic PDA closure using indomethacin and ibuprofen. The patient was discharged with an estimated 2/3 systemic pulmonary artery pressure. One month after hospital discharge, on low-flow oxygen supplementation (0.5 L/min FiO2 100%), at the corrected age of 16 weeks, she was readmitted to our emergency department with signs of respiratory distress and circulatory decompensation. Echocardiography demonstrated suprasystemic PH. Severe PH persisted despite initiated invasive mechanical ventilation, triple vasodilating therapy [iNO, macitentan, and continuous intravenous (IV) sildenafil], as well as levosimendan, milrinone, and norepinephrine for recompensation from cardiac shock. Thus, we started off-label oral selexipag therapy (oral IP receptor agonist) in the smallest patient reported so far (4 kg body weight). Subsequently, RV systolic pressure decreased to half-systemic, allowing successful weaning of iNO, norepinephrine, and milrinone, and extubation of the patient over 4 days. The infant was discharged 4 weeks after pediatric intensive care unit (PICU) admission in stable cardiorespiratory condition, with an oral, specific, triple antihypertensive PAH-targeted therapy using selexipag, macitentan, and sildenafil as well as oxygen therapy at low-flow (0.5 l/min) and spironolactone. The first cardiac catheterization at the age of 9 months under aforementioned triple PAH-targeted therapy revealed mild PH with 35% systemic PA pressure (mPAP/mSAP = 0.35) and isolated pulmonary vein stenosis. A transthoracic biopsy at the age of 12 months confirmed the diagnosis of BPD and further showed pulmonary interstitial glycogenosis and severe pulmonary capillary hemangiomatosis, without involvement of the pulmonary venules (chILD A2, A3, and B4 according to the Deutsch-Classification). The patient is currently in stable cardiorespiratory condition undergoing triple PH-targeted therapy including selexipag. This report highlights the potential benefits of the oral prostacyclin mimetic selexipag as an early add-on PH-targeted drug in chronic PH of infancy (cPHi).

Echocardiography for the Assessment of Pulmonary Hypertension and Congenital Heart Disease in the Young

While invasive assessment of hemodynamics and testing of acute vasoreactivity in the catheterization laboratory is the gold standard for diagnosing pulmonary hypertension (PH) and pulmonary vascular disease (PVD) in children, transthoracic echocardiography (TTE) serves as the initial diagnostic tool. International guidelines suggest several key echocardiographic variables and indices for the screening studies when PH is suspected. However, due to the complex anatomy and special physiological considerations, these may not apply to patients with congenital heart disease (CHD). Misinterpretation of TTE variables can lead to delayed diagnosis and therapy, with fatal consequences, or–on the other hand-unnecessary invasive diagnostic procedures that have relevant risks, especially in the pediatric age group. We herein provide an overview of the echocardiographic workup of children and adolescents with PH with a special focus on children with CHD, such as ventricular/atrial septal defects, tetralogy of Fallot or univentricular physiology. In addition, we address the use of echocardiography as a tool to assess eligibility for exercise and sports, a major determinant of quality of life and outcome in patients with PH associated with CHD.