Document resource
Introduction Pulmonary Veno-Occlusive Disease (PVOD) is a very rare subtype of pulmonary arterial hypertension (PAH) with reported annual incidence of 0.1–0.2 cases per million. Aetiology includes idiopathic, heritable, connective tissue disease and toxins. Knowledge is limited to case reports describing variable responses to PAH therapeutics and prognosis is poor due to heart failure. Typical CT chest findings include septal lines, ground glass opacities and mediastinal lymphadenopathy, but diagnosis frequently follows deterioration with standard PAH therapy. Definitive treatment is lung transplantation. We report two cases of genetically confirmed PVOD with implanted devices for remote monitoring. Both patients demonstrated a positive response to PAH therapy and remotely detected clinical worsening events (CWE).Methods Patients were enrolled in the Feasibility of Novel Clinical Trial Infrastructure, Design and Technology for Early Phase Studies in Pulmonary Hypertension (FIT-PH, REC 19/YH/0354) and implanted with a pulmonary artery pressure (CardioMEMS TM) and insertable cardiac monitors (Reveal LINQ). Patients also gave written consent for this case report. Longitudinal follow-up included a minimum of weekly home pulmonary artery pressure readings. Physiological readings (e.g. total pulmonary resistance (TPR), wood units (WU)) were monitored remotely by clinicians to assess ongoing treatment response.Results Both cases involve EIF2AK4 mutations diagnosed following successful initiation of combination PAH therapeutics. Both travel 1–2 hours for clinic visits. CT chests showed subtle ground glass nodularity also commonly observed in PAH. On initiating of dual oral therapy, Case 1 showed an NT-proBNP reduction of 2160ng/L to 136ng/L. Remaining symptomatic at 4-month follow-up, CardioMEMS was implanted and intensification with riociguat demonstrated a further reduction in TPR ( figure 1). An episode of decompensated heart failure occurred 5 months later, with good response to diuretics, negating admission. Case 2 unusually showed a nitric oxide response at baseline right heart catheterisation and was commenced initially on diltiazem and with subsequent addition of sildenafil. At 4-month follow-up, CardioMEMS was implanted and macitentan added. 8 months later, significant reduction in TPR with nocturnal CPAP was observed (figure 1). The patient remained stable under remote follow-up for 3 years before remotely detected clinical worsening.Conclusion PVOD has a heterogeneous response to PAH therapy and a high risk of CWEs. It remains unclear how to identify responders and non-responders without a trial of therapy. To our knowledge, this is the first report in PVOD to highlight the potential value of remote monitoring to identify CWEs and assess remotely the response to PAH therapies.Abstract 5-012 Figure 1Total pulmonary resistance captured remotely demonstrating therapeutic response and a clinical worsening event defined as an episode of decompensated heart failure