Q-SPECT CT in the assesment of post-pulmonary embolism complications: a new perspective on risk stratification and management

Abstract

Introduction. Pulmonary embolism (PE) is a severe cardiovascular condition associated with significant morbidity, often resulting in long-term complications despite adequate anticoagulation. Chronic thromboembolic pulmonary hypertension (CTEPH) develops in over half of PE survivors, affecting both functional capacity and prognosis. Identifying high-risk individuals at an early stage is crucial for optimizing clinical outcomes. Quantitative Single Photon Emission Computed Tomography with CT (Q-SPECT CT) has gained recognition as an advanced imaging modality capable of detecting residual perfusion abnormalities, aiding risk assessment and clinical decision-making. Materials and Methods. A prospective study was conducted, enrolling patients who had completed anticoagulation therapy (3–6 months) after a confirmed PE episode. Participants underwent a detailed clinical evaluation, echocardiography, biomarker analysis, and Q-SPECT CT imaging to assess residual perfusion defects. Statistical correlations were analyzed using Spearman’s test. Results. Preliminary data indicate that 83.3% of symptomatic PE survivors experience persistent dyspnea, with Q-SPECT CT revealing residual perfusion abnormalities in 60% of cases. Echocardiographic findings demonstrated a significant correlation between the TAPSE/PSAP ratio and NT-proBNP levels (p < 0.001), right ventricular (RV) strain variations (p < 0.02), and the likelihood of pulmonary hypertension (p < 0.001). Furthermore, perfusion defects identified via Q-SPECT CT were associated with the presence of thoracic pain (p < 0.03) and an increased probability of pulmonary hypertension (p < 0.03). No statistically significant correlations were observed between Q-SPECT CT findings and RV strain (p = 0.9), 3D right ventricular ejection fraction (RVEF) (p = 0.1), or TAPSE/PSAP ratio (p = 0.08). Conclusions. Q-SPECT CT proves to be a valuable tool for evaluating post-PE complications, particularly in patients with suspected pulmonary hypertension. Its ability to detect persistent perfusion deficits allows for a more refined risk stratification, supporting tailored management strategies and further diagnostic refinement. Integrating Q-SPECT CT into routine follow-up protocols may improve long-term outcomes in PE survivors.