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Recruiting NCT07613632

Changes in Regional Ventilation-Perfusion Match Following Percutaneous Transluminal Angioplasty for Arteriovenous Graft Thrombosis

— Observational Arteriovenous Graft Thrombosis End Stage Renal Disease on Dialysis

For patients and families

In plain language

An automatic summary of structured registry data. It is an orientation aid, not a substitute for the official protocol or a physician assessment.

What is being studied
The protocol lists: Electrical Impedance Tomography (EIT) Monitoring.
Who it may be relevant to
Registry conditions: Arteriovenous Graft Thrombosis, End Stage Renal Disease on Dialysis. Basic parameters: from 18 years · All.
What needs checking
Age, condition and sex are only basic indicators. Prior treatment, laboratory values and other mandatory requirements appear in the eligibility criteria below.
Where it takes place
China
Next step
Save the trial, show it to the treating physician, and confirm current recruitment with the study center. Costs, documents and travel →

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Official title

Changes in Regional Ventilation-Perfusion Match Following Percutaneous Transluminal Angioplasty for Arteriovenous Graft Thrombosis: A Prospective Observation Pilot Study

Overview

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.

Detailed description

Arteriovenous graft (AVG) thrombosis is a major source of vascular access failure in ESRD. PTA restores patency through balloon dilation and mechanical thrombus compression. Minor embolic debris can reach the pulmonary bed, transiently disturbing perfusion distribution and V/Q matching. Because the pulmonary circulation is sensitive to sudden peripheral hemodynamic shifts, the PTA period provides a unique opportunity to observe lung perfusion response dynamically.

This single-center, prospective, observational pilot study will continuously record regional ventilation and perfusion by EIT at six time points: 10 min before PTA, at recanalization, and 10, 20, 30 min after, and at procedure completion. Measured variables include: V/Q matching index (primary), physiological dead space fraction (Vd/Vt), intrapulmonary shunt fraction, SPO₂/FiO₂ ratio, and hemodynamic data (balloon pressure, recanalization time, blood flow recovery). Results will be analyzed using repeated-measures ANOVA or mixed-effects modeling.

Interventions

  • Diagnostic test Electrical Impedance Tomography (EIT) Monitoring
    Non-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.

Primary outcome measures

  • Change in Ventilation-Perfusion Matching Index [Time frame: Baseline (10 min before PTA), immediate post-recanalization, 10, 20, 30 minutes, and procedure end.]
Secondary outcome measures (4)
  • Change in Peripheral Oxygen Saturation [Time frame: Baseline (10 min before PTA), immediate post-recanalization, 10, 20, 30 minutes, and procedure end.]
  • Change in Physiological Dead Space Fraction [Time frame: Baseline (10 min before PTA), immediate post-recanalization, 10, 20, 30 minutes, and procedure end.]
  • Change in Intrapulmonary Shunt Fraction [Time frame: Baseline (10 min before PTA), immediate post-recanalization, 10, 20, 30 minutes, and procedure end.]
  • Change in Regional Ventilation and Perfusion Distribution [Time frame: Baseline (10 min before PTA), immediate post-recanalization, 10, 20, 30 minutes, and procedure end.]

Eligibility criteria

Inclusion criteria

  • Age ≥ 18 years.
  • Diagnosis of end-stage renal disease receiving maintenance hemodialysis.
  • Documented AVG thrombosis requiring PTA.
  • Able to cooperate and tolerate EIT monitoring.
  • Provided written informed consent.

Exclusion criteria

  • 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.
  • Pregnancy or breastfeeding.
  • Any other circumstance judged unsuitable by investigator.

Criteria are shown verbatim from the registry (in English). Final eligibility is always assessed by the study center.

Healthy volunteers: No

Study design

Observational model
Cohort

Study locations

China · 1 center
  • The First Affiliated Hospital of Wannan Medical College (Yijishan Hospital of Wannan Medic — Wuhu

Identifiers

NCT: NCT07613632 · 2026-ICU04

Primary sources (government registries)

View this study on ClinicalTrials.gov ↗