The HeRO graft is primarily intended for use in patients with moderate to severe central venous occlusion and/or stenosis as demonstrated by upper extremity and thoracic central venous imaging [4]. Previously, the presence of central venous occlusion meant that few options remained for dialysis access and that these patients had reached the final conventional stages of dialysis. Alternatives at this juncture carried significant morbidity. The most morbid of these options was direct right atrial access via sternotomy or thoracotomy as well as the use of translumbar or hepatic catheters [3]. Central venous reconstruction was also attempted in certain cases but with poor success [3, 16–18]. The most common alternative today is the tunneled dialysis catheter (TDC); however a high incidence of infection, malfunction, poor flow rates, and mortality has incentivized the investigation of novel alternatives [5, 6]. As such, patients who have exhausted all traditional access methods and have succumbed to central venous occlusion are ideal candidates for the HeRO graft.

For patients with a preexisting AV access (arteriovenous fistula (AVF) or AVG) that is failing, the use of the HeRO device has been described as a salvage therapy. In these instances, the graft component of the HeRO device is anastomosed to the existing AV access, diverting all flow through an uninterrupted pathway to the right atrium. In some cases, this can allow for the immediate use of the access without the need for ligation or explanation. Early use also obviates the need for a bridging TDC, which carries additional clinical sequelae [5]. While balloon angioplasty or stenting can be used for short-term benefits in certain cases, the early experience would suggest that the HeRO graft provides a more durable solution to mitigating the complications associated with central venous occlusion in the dialysis population [3].

Relative contraindications for HeRO implantation include a brachial artery diameter less than 3 mm, congestive heart failure with ejection fraction less than 20 %, and systolic blood pressure less than 100 mmHg [6]. However, there is no significant clinical data to support these claims. As with any intervention, particularly in this high-risk population, the risks and benefits of each alternative must be carefully evaluated prior to selection.

Pre-procedural history and physical exam should be performed prior to selection of the HeRO graft. A detailed account of prior and current dialysis access, vascular interventions, and status related to potential kidney transplantation should be noted. Imaging of the upper extremity and central veins will reveal sites of occlusion. Conventional venography provides excellent imaging of the axillary and subclavian veins, but we find that CT or magnetic resonance (MR) angiography in the arterial and venous phases provides the most comprehensive data in cases of total central vein occlusion (Fig. 32.4). Central vein recanalization requires evaluation of the structures adjacent to the native venous anatomy and requires careful operative planning. As with any AV access surgery, there are three main principles for success: good inflow, good conduit, and good outflow. When planning for HeRO graft placement, in general, inflow is less of an obstacle. However, one must be aware of atherosclerotic disease as well as severe diabetic arterial vasculopathy. Establishment of central venous access can often be the most challenging aspect of the procedure. In the patient with moderate stenosis, percutaneous access via the most common routes (i.e., internal jugular and subclavian vein) has a high rate of success. In cases of severe central stenosis or occlusion around an indwelling tunneled dialysis catheter, central venous access can be attained with ease by exposing the catheter at its venous access point, transecting and guiding wire placement (Fig. 32.5). However, in those patients with severe stenosis or occlusion without access, preoperative central vein recanalization is recommended to ensure a successful HeRO graft implantation.

The procedure is performed in the operating room or hybrid OR under general anesthesia to facilitate the need for operative management of complications such as bleeding and intrathoracic venous rupture or vascular injury, as well as the vigorous nature of subcutaneous tunneling in the neck and chest. Preoperative antibiotics are administered per standard protocol.

A venous access site is selected first. Standard options include the internal jugular, subclavian, axillary, or femoral veins. The internal jugular vein is the most common choice, followed by the subclavian vein and then femoral vein [3]. The right or left side can be accessed interchangeably. The venous outflow component (VOC) of the device consists of a 5 mm ID silicon stent reinforced with nitinol and is inserted through the venous target and into the right atrium using the Seldinger technique. Traversing the stenotic lesion can be challenging depending on the luminal area. Once the wire traverses the lesion, balloon angioplasty of the central veins is recommended prior to delivering the HeRO VOC [6]. We recommend using an 8 × 40 mm high-pressure balloon over a stiff wire in order to create sufficient space to deliver the VOC. Using a stiff wire improves the maneuverability of large devices in tight spaces and reduces the risk of tearing or rupturing the central veins when inserting rigid dilators and peel-away sheaths. Once the VOC traverses the lesion over the wire, angiography is used to verify the radiopaque tip location at the cavoatrial junction. We find that the dome of the right hemidiaphragm is a useful initial landmark to guide placement of the VOC tip close to the middle of the right atrium. Once confirmed, the opposite end of the venous outflow is tunneled subcutaneously toward the shoulder or delto-pectoral groove and is delivered outside the body through a counter incision. Care should be taken to avoid tunneling the VOC too lateral which can lead to kinking of the graft/connector interface.

Attention is then turned to the arterial side. Graft material is most commonly expanded polytetrafluoroethylene (ePTFE). This material requires time for tissue incorporation, although the use of early-access graft material such as Flixene or Acuseal has been described [7]. This early-use method requires an additional anastomosis to the most proximal aspect of the arterial end but can be used within 24–72 h, which thus obviates the need for a bridging TDC and its added risks. Next, the arterial graft is tunneled from the counter incision out toward the bicep in a generously curved tract to avoid kinking. The distal end is brought out through an incision over the expected arterial anastomosis site. The arterial and venous ends at the previous counter incision are coupled using the titanium connector by sliding the VOC over the hose-barb connection.

In late 2015, CryoLife released its new HeRO Graft Adapter in a limited launch. The development of this feature came about as a result of clinician feedback and the desire to use the surgeon’s graft of choice as the cannulation segment (particularly early cannulation or low-bleed grafts). At this point, the only two grafts approved for use with the Adapter are the Gore® Acuseal (W.L. Gore & Associates, Flagstaff, AZ and Flixene® Standard Wall Atrium Medical Corp., Hudson, NH) hemodialysis grafts (Fig. 32.6). A final angiogram is performed through the entire access circuit to ensure the VOC is in the proper position and there is no kinking at the connector or within the graft tunnel. We then perform the arterial graft anastomosis to the selected artery. Incisions are fully closed and the HeRO device can be safely accessed in 3–4 weeks. While the bridging TDC is in place, we recommend administration of vancomycin with hemodialysis sessions until removed [4].

When salvaging preexisting AV access, the arterial inflow from an AVF or AVG can be anastomosed directly to the HeRO AV graft while the venous end is installed in the usual fashion (Fig. 32.7). Allan and Gage describe this method in several case reports with favorable success [8].