Usefulness of peripheral-pressure-directed balloon pulmonary angioplasty for chronic thromboembolic pulmonary hypertension
Abstract Background Balloon pulmonary angioplasty (BPA) in expert center may be considered in patients with chronic thromboembolic pulmonary hypertension (CTEPH) who are technically non-operable for pulmonary endarterectomy. BPA based on objective quantitative methods has not been established. The endpoint at BPA sessions has not been clarified yet. Objectives The purpose of this study was to investigate the usefulness of BPA according to peripheral pressure measured by pressure wire or catheter. Methods This study included consecutive 143 CTEPH who underwent cardiopulmonary exercise test with right heart catheterization after BPA. All patients were divided into 2 groups such as angio-guided (n=47) group or pressure-guidedgroup (n=96). In pressure-guided group, the pulmonary arterial pressure (PAP) proximal and distal to the target lesion and the ratio of the 2 pressures were measured by the pressure wire or catheter. the endpoint was determined to when the pressure ratio of distal to proximal pressures was >0.7 to 0.8 finally. The dilation was stopped when the distal mean PAP after each dilation reached 35 mm Hg and when the baseline mean PAP was >35 mm Hg. Changes of hemodynamic parameters such as PAP and pulmonary vascular resistance (PVR) from baseline, and mean PAP and PVR at peak oxygen consumption, and pulmonary arterial pressure – cardiac output (PA-CO) slope were compared between two groups. All data except changes of hemodynamics from baseline were expressed by median [25th percentile-75th percentile]. Changes of hemodynamics from baseline were expressed by average [95% confidence interval] Results The median age and male were 66 [56–72] years old and 35. There were no significant differences in number of sessions and dilated vessels between two groups (Angio-guided group vs. Pressure-guided group: 4 [3–6] vs. 4 [3–5], P>0.05; 19 [12–22] vs. 17 [13–22], P>0.05). Changes of PAP and PVR from baseline in pressure-guided group was significantly higher than in angio-guided groups (Angio-guided group vs. Pressure-guided group; ΔPAP: −19 [−20 to −17] vs. −20 [−21 to −20], P>0.05; ΔPVR: −6.0 [−6.3 to −5.7] vs. −6.6 [−6.8 to −6.3], P<0.01). Mean PAP and PVR at peak oxygen consumption (VO2) and PA-CO slope in pressure-guided group were significantly lower than in angio-guided group (Angio-guided group vs. Pressure-guided group; PAP at VO2: 43 [36–50] vs. 39 [34–43], P<0.05; PVR at VO2: 2.7 [1.9–4.5] vs. 2.2 [1.6–2.9], P<0.01; PA-CO slope: 3.8 [2.1–5.2] vs. 2.9 [1.9–4.0], P<0.05). Conclusions Peripheral-pressure-directed BPA can improve hemodynamics at rest and exercise more effectively. Funding Acknowledgement Type of funding source: None