Where’s the thin red line between benefit and non-benefit left-to-right shunt closure

  • Dr Supaporn Roymanee, Prince of Songkla University, Had Yai, Songkla, Thailand
  • Dr Saranwan Phetphisal, Prince of Songkla University, Had Yai, Songkla, Thailand
  • Dr Nakharin Tonklang, Prince of Songkla University, Had Yai, Songkla, Thailand

    • Background: In severe pulmonary arterial hypertension (PAH) associated with left-to-right shunts or impending Eisenmenger physiology patients, there were not only no consensus criteria to predict reversibility of PAH but also unclear benefit outcomes post shunt closure.
    Method: We reviewed hemodynamic parameters in three patients with severe PAH associated left-to-right shunt who underwent uneventful transcatheter closure and intermediate post procedure showed decrement of PAH, also with improvement in theirs exercise performance and quality of life.
    Result: All patients have equalization of pulmonary artery pressure (PAP) and systemic artery pressure (AoP) combined with high pulmonary vascular resistance (Rp). Pre and post 100% oxygen administration data were collected, results as show in Table.
    Post oxygen administration, parameters showed common features as follows: 1) Rp decreased > 25%, 2) Rp:Rs decreased > 25%, 3) Qp:Qs > 2, 4) The ratio of systolic or mean between PAP and AoP decreased > 20%, 5) Lower diastolic blood pressure of PAP as compare with AoP at least 20 mmHg, 6) Aortic saturation (SaO2) was > 95%. We propose that beside trial occlusion which require more equipments, time consumption and costly, patients who have at least 4 from 6 criteria will achieve costless, safe and benefit transcatheter closure.
    Conclusion: We should focus on hemodynamic data changing after oxygen administration, to predict reversibility of PAH and beneficial effect from left-to-right shunt closure.

    Lesion Age Condition SaO2 PAP AoP Qp:Qs Rp:Rs Rp
    (year) (%) (S/D/M) (S/D/M) (WU/m2)
    1. ASD 23 mm 56 - room air 94 101/29/53 101/69/78 1.2 0.55 20.8
    -100% O2 99 101/28/49 123/77/95 2.3 0.23 11.9
    2. PDA 24 mm 38 - room air 95 92/50/67 90/51/68 1.5 0.67 9.2
    -100% O2 99 85/69/54 85/69/54 2.8 0.30 2.6
    3. PDA 10 mm 41 - room air 80 102/44/64 109/55/78 2.7 0.31 5.5
    -100% O2 100 94/46/67 157/58/78 2.8 0.23 3.3