Patients with end-stage renal disease (ESRD) often require arteriovenous grafts (AVG) for hemodialysis. AVG thrombosis is a common complication, usually managed by percutaneous transluminal angioplasty (PTA) to restore blood flow. PTA achieves patency by balloon-mediated compression and fragmentation of thrombus. Small thrombus fragments may enter the venous circulation and cause transient pulmonary microembolism, leading to ventilation-perfusion (V/Q) mismatch. This study uses electrical impedance tomography (EIT) to noninvasively monitor short-term changes in regional ventilation and perfusion during and after PTA, exploring the immediate pulmonary physiological consequences of thrombus fragmentation and revascularization in dialysis patients.
Age ≥ 18 years.
Diagnosis of end-stage renal disease receiving maintenance hemodialysis.
Documented AVG thrombosis requiring PTA.
Able to cooperate and tolerate EIT monitoring.
Severe respiratory failure incompatible with supine position.
Thoracic skin condition or deformity preventing EIT electrode placement.
Acute pulmonary embolism or acute pulmonary edema before procedure.
NYHA Class IV heart failure or hemodynamic instability.
Patients with end-stage renal disease (ESRD) undergoing maintenance hemodialysis who present with thrombosed arteriovenous grafts (AVG) requiring clinically indicated percutaneous transluminal angioplasty (PTA) to restore patency. The study population will consist of adult patients (18-80 years) admitted to the interventional radiology or dialysis access unit of the First Affiliated Hospital of Wannan Medical College (Yijishan Hospital). All participants will receive routine PTA treatment as part of standard care. EIT monitoring will be applied non-invasively to collect ventilation and perfusion signals before and after PTA. No additional interventions beyond routine clinical management will be introduced.
Cohort
Prospective
Electrical Impedance Tomography (EIT) Monitoring
Diagnostic testNon-invasive 16-electrode EIT belt applied at the 4th intercostal level. Continuous data acquisition begins 10 min pre-PTA, continues throughout balloon angioplasty, and up to 30 min post-recanalization. No alteration to standard clinical care.
Change in Ventilation-Perfusion Matching Index
Quantitative index derived from EIT ventilation and perfusion maps, indicating spatial regional correlation of air and blood flow distribution.
Change in Peripheral Oxygen Saturation
Change in Physiological Dead Space Fraction
Ratio of physiologic dead space to tidal volume, calculated by EIT validated algorithm, reflecting inefficiency of ventilation.
Change in Intrapulmonary Shunt Fraction
Percentage of the lung region showing perfusion without ventilation, estimated from EIT perfusion signals.
Change in Regional Ventilation and Perfusion Distribution
Variation in spatial patterns of pulmonary ventilation and perfusion derived from pixel-based EIT data.
Click on the lead sponsor to view all of their trials.
