High-Output Heart Failure, Pulmonary Hypertension and Right Ventricular Failure in Patients With Arteriovenous Fistulas: A Call to Action

Treating hemodialysis access thrombosis with the InThrill Thrombectomy System: Technique and case report

The purpose of this report is to describe via a case example an efficient mechanical thrombectomy technique for hemodialysis access thrombosis using the InThrill Thrombectomy System (Inari Medical, Irvine, CA). A man in his late 60s with end-stage renal disease and a thrombosed femoral arteriovenous graft (AVG) underwent a thrombectomy procedure to remove all thrombotic material including the arterial plug and restore use of the graft for hemodialysis. The InThrill Thrombectomy System used in this procedure consists of a mechanical thrombectomy catheter with a wall-apposing coring element and a sheath with a retractable funnel and aspiration port. The technique starts with gaining wire and sheath access towards the venous outflow. The InThrill Thrombectomy catheter is deployed proximal to the sheath to sequentially remove small segments of thrombus thus avoiding sheath obstruction. A locking syringe is used for rapid aspiration, reducing or eliminating the need to remove the InThrill sheath with every mechanical thrombectomy pass. Finally, the arterial plug is pulled using a Fogarty balloon sheath (Edwards Lifesciences, Irvine, CA) and extracted using the InThrill catheter, removing what may be the nidus for recurrent AV access thrombosis. The technique described here provided a means to remove all thrombotic material including the arterial plug in a planned, sequential manner, without the need for thrombolytics. Patency was restored to the patient's femoral AVG within 60 minutes, and hemodialysis resumed shortly thereafter. Further studies are needed to support long-term efficacy of this thrombolytic-free treatment option.

Determinants of pulmonary hypertension in patients with end-stage kidney disease and arteriovenous access

BACKGROUND

Pulmonary Hypertension (PH) is a sequela of arteriovenous (AV) fistulas (AVF) or AV grafts (AVG) in patients with end-stage kidney disease (ESKD) due to the creation of shunt physiology and increased pulmonary blood flow. PH has been consistently associated with increased mortality but there is a paucity of data regarding management.

RESEARCH QUESTION

The objective of this study was to identify risk factors and outcomes in patients who develop PH after AVF or AVG creation for hemodialysis access.

METHODS

Using the United States Renal Data System, we identified all patients over age 18 initiated on dialysis from 2012-2019 who did not receive renal transplant. We identified a) the predictors of PH in patients with ESKD on hemodialysis; b) the independent mortality risk associated with development of PH.

RESULTS

We identified 478,896 patients initiated on dialysis from 2012-2019 of whom 27,787 (5.8 %) had a diagnosis of PH. The median age was 65 (IQR: 55-74) years and 59.1 % were male. Reduced ejection fraction, any congestive heart failure, obstructive sleep apnea, and female sex were the strongest predictors of PH diagnosis. Both AVG and AVF were also associated with an increased rate of PH diagnosis compared to catheter-based dialysis (p < 0.001). PH portended a poor prognosis and was associated with significantly increased mortality (p < 0.001).

CONCLUSIONS

Patients with AVF or AVG should be screened using echocardiography prior to creation and monitored with serial echocardiography for the development of PH, and if present, considered for revision of the AVA. This is also the first study to identify that AVG are a risk factor for PH in dialysis patients.