The Predictive Value of Quantitative Analysis of SPECT V/Q Imaging for Postoperative Persistent/Recurrent Pulmonary Hypertension in Patients With Chronic Thromboembolic Pulmonary Hypertension After Pulmonary Endarterectomy

Pulmonary endarterectomy (PEA) is a highly effective treatment for chronic thromboembolic pulmonary hypertension (CTEPH). However, persistent or recurrent pulmonary hypertension (persistent/recurrent PH) following surgery can adversely impact patients' outcomes. This study investigated the predictive value of preoperative SPECT ventilation/perfusion (V/Q) imaging for post-PEA persistent/recurrent PH. Between 2016 and 2022, CTEPH patients at our hospital underwent PEA after right heart catheterization (RHC) and SPECT V/Q imaging and were followed for 2 years. Postoperative mean pulmonary artery pressure (mPAP) ≥ 25 mmHg indicates persistent/recurrent PH. Correlations were explored between the occurrence of postoperative persistent/recurrent PH and preoperative parameters, including systolic pulmonary artery pressure (sPAP), mPAP, pulmonary vascular resistance (PVR), and parameters of the SPECT V/Q scan. Seventy-four patients were enrolled, including 52 males (71.6%). Seventeen patients (23%) developed persistent/recurrent PH within 2-80 weeks after surgery. The persistent/recurrent PH and non-persistent/recurrent PH groups exhibited statistically significant preoperative differences in preoperative mPAP, sPAP, PVR, Begic's score, and V/Q mismatched volume percentage (<i>p</i> < 0.05 for all). ROC curve analysis identified the optimal cut-off values: mPAP-44.5 mmHg, sPAP-79.5 mmHg, PVR-944 dyn × s × cm^-5, Begic's score-16.5, and V/Q mismatched percentage-35.58%. Cox regression analysis showed that preoperative mPAP and V/Q mismatched percentage were significant predictors of persistent/recurrent PH-free survival time, with relative hazards of 3.29 (95% CI: 1.08-10.01) (<i>p</i> = 0.036) and 3.94 (95% CI: 1.25-12.42) (<i>p</i> = 0.019), respectively. These findings indicate that metrics derived from SPECT V/Q scans can effectively stratify post-PEA patients by the risk of persistent/recurrent PH. Quantitative parameters could provide complementary information that enhances predictive accuracy of postoperative persistent/recurrent PH at the individual level. This may support the optimization of clinical management strategies, particularly by guiding patient-specific therapeutic interventions, such as balloon pulmonary angioplasty for patients with persistent/recurrent PH after PEA.