We report the novel use of a recently approved catheter device, AngioVac (Vortec Medical, Norwell, MA USA), in a Jehovah’s Witness who presented a very-high-risk proposition for redo sternotomy.
Cardiac surgery in a Jehovah’s Witness requires appropriate strategic management of preoperative and intraoperative details to minimize complications. In 1977, Ott and Cooley1 reported on 542 cardiovascular operations performed on Jehovah’s Witnesses without transfusing blood and concluded that these procedures can be done with an acceptably low risk. Contemporary strategies include minimally invasive approach with or without off-pump technique, cardiopulmonary bypass management (mini-extracorporeal circuit, retrograde autologous prime, heparin-coated circuits, and lower activated clotting time), transfusion science (autologous blood donation; acute normovolemic hemodilution; minimum acceptable hemoglobin limit, 7 g/dL2), anesthetic strategies (vasopressors, colloids), meticulous operative details and use of cell saver, pharmacologic support of hemostasis (factor 7, aprotinin, biological “glues,” desmopressin), and stimulation of erythropoiesis (erythropoietin).
The 59-year-old patient, a Jehovah’s Witness and with a long cardiac history, was referred for urgent surgical consult for a large 8-cm mobile right atrial thrombus tracking from an occluded superior vena cava (SVC) and prolapsing in and out through a bioprosthetic tricuspid valve (TV). Three-dimensional (3D) echocardiography clearly showed the issue (Fig. 1).
Initially diagnosed with complete heart block, she has had multiple cardiac pacemaker procedures. Permanent pacemaker insertion via right subclavian vein was done at age 20 years and revised at age 40 years. In 2008, presenting with pulmonary and cerebral emboli, central cyanosis, and polycythemia, gated computed tomography angiography confirmed an 18 × 12–mm Ostium secundum atrial septal defect (ASD) and an abnormal TV consistent with Epstein anomaly, in addition to thrombus on right atrium pacing wires. Right heart and transseptal left heart catheterization confirmed significant right to left shunting. Given the acute presentation, initially, an Amplatzer septal occluder was used to close the ASD. Later, for severe tricuspid regurgitation, a biological TV replacement was performed via median sternotomy. Simultaneously, the right internal pacing leads were excised, leaving a remnant within the proximal SVC. Right ventricle epicardial leads were placed and led into a left rectus abdominal pocket. A month later, a large pericardial effusion was drained via a left anterior mini thoracotomy. The most recent intervention, 2 months ago, was Dual Chamber Rate Adaptive Pacemaker (DDDR) /Automatic Implantable Cardioverter Defibrillator (AICD) generator insertion for symptomatic ventricular tachycardia. Owing to distal right subclavian stricture and a prosthetic TV, a left innominate transvenous ICD lead was placed into the proximal SVC, as well as a subcutaneous ICD lead in the left posterolateral chest wall. The permanent pacemaker/ICD device was now repositioned in a left infraclavicular pocket, after adding extensions and then rerouting the previous subcostal epicardial pacing leads. She has a previous history of deep vein thrombosis and has been on adequate anticoagulation since the valve replacement. Her hemoglobin and hematocrit levels on the current admission were 12.5 g/dl and 37% respectively.
Clot formation on complex pacemaker patients is not uncommon. This clot was potentially fatal if it were to embolize into the pulmonary artery or get trapped in the bioprosthetic TV. In this scenario, thrombolytic therapy was not a good option. This Jehovah’s Witness poses some unique and critical problems of risks and safety with a conventional open operative approach:
* Increased re-sternotomy entry risks and of significant bleeding due to adhesions from a relatively recent sternotomy and pericardial effusion drainage
* SVC cannulation for cardiopulmonary bypass poses issues: the near total occlusion of SVC with dilated azygous collateral flow, the presence of mobile clot, and the indwelling pacing/defibrillator leads
* ASD device in situ
* Complex history and “precious” epicardial leads in situ
An image from the 3D structural computed tomography angiography captures these multiple issues (Fig. 2).
Alternative Novel Solution
A minimally invasive solution was used. The AngioVac (Vortex Medical Inc), a recently approved device, is a novel catheter-based system that allows suction, filtering, and reinfusion of blood, in a set up akin to venovenous extracorporeal support system. Our AngioVac circuit consisted of the 18-French (F) AngioVac cannula used as the inflow cannula, an Edwards femoral arterial 18-F cannula as the outflow cannula, a Jostra Rotaflow centrifugal pump for suction, and a Terumo 150-µm bubble trap with filter to retain any clot suctioned into the cannula and circuit. The end of the AngioVac cannula has a balloon-actuated, expandable funnel-shaped tip (Fig. 3, inset, bottom left) to facilitate inflow and capture of the undesirable material from the circulation. Anticoagulation was maintained at an activated clotting time of more than 250 seconds.
A hybrid procedure was carried out, under general anesthesia, in the cardiac catheterization laboratory with a multidisciplinary team of interventional and imaging cardiologists, cardiac surgeons, cardiac anesthetists, and perfusionists. Because the AngioVac device cannula is not a smoothly tapered end, an open surgical approach through a 1-cm venotomy on the right femoral vein was used. Lateral traction sutures were used to open the venotomy. A “shoe-horn” maneuver then facilitated the safe insertion of the small step of the distal cannula profile into the femoral vein. This caution was used to prevent the possibility of bleeding/hematoma that is a real risk with an alternate purely percutaneous approach. A percutaneous approach, however, was used via the left femoral vein for the tapered outflow cannula.
Using a combination of fluoroscopy and 2D and 3D transesophageal echocardiogram, the AngioVac cannula was advanced into the inferior vena cava/right atrium junction initially (Fig. 3). The extracorporeal circuit was initiated with 4000 rpm suction on the inflow cannula. However, initial attempts to engage the clot failed and instead sucked in the right atrial wall. An alternate approach of echo-guided advancement of cannula into the SVC and delayed initiation of lower suction thereafter proved successful to engage the clot. In our patient, because the clot was long-standing and organized, as it was suctioned, it remained at the distal funnel entrance to the cannula, instead of passing through into the reservoir trap. With the suction continuously on, the AngioVac cannula (with clot) was retracted carefully and the clot was extracted manually via the right femoral venotomy (Fig. 4). In hindsight, the open approach venotomy facilitated clot extraction that would otherwise have proven an issue had a percutaneous approach been adopted initially. From the time of establishing femoral venovenous circulation, the procedure took 20 minutes and the total bypass time was 11 minutes. Total fluoroscopy time was 12 minutes. There was minimal blood loss. Most of the blood in the extracorporeal circuit was transfused back to the patient. Postprocedure echocardiogram confirmed complete removal of clot from the atrium.
Postoperatively, there were no complications. The patient did not require any inotropes, was on minimal oxygen FiO2, and was extubated at 4 hours. The patient was transferred from the intensive care unit to the floor within 24 hours of the procedure. The hemoglobin/hematocrit levels on discharge from intensive care unit were 12 g/dl and 36%, respectively. The retrieved mass measured 7.3 × 1.4 × 0.7 cm. Histology of the material was consistent with a chronic thrombus. Anticoagulation was restarted.
The manufacturer states the uses of the AngioVac catheter for en bloc removal of undesirable intravascular material such as clot, thrombus tumor, myxoma, and vegetation while maintaining flow during extracorporeal circulation. At the time of the procedure, we were not aware of any other published case report of the use of AngioVac in a complex cardiac surgery case or a Jehovah’s Witness.
Redo sternotomy and an open cardiac procedure would clearly have significantly increased the risks (mortality and morbidity) and length of hospital stay. The hybrid device and option may have been a potentially lifesaving solution. Important lessons were learned on how to effectively use the device. A combination of open vascular access for the minimally invasive device was safer than a pure percutaneous approach.
The management and use of the blood within this extra corporeal circuit have ethical implications for the Jehovah’s Witness. The set-up used is not an autotransfusion but a system of extracorporeal circulation in continuity with the patient’s circulation. The continuity between the receiving venous side and the arterial reinfusion port is maintained. Transfusion of shed blood in such a system is one that most Jehovah’s Witness patients will accept. This is unlike the conventional use of a cell saver where the continuity of the patient’s blood column is broken and, as such, not acceptable to a Jehovah’s Witness.
A small case series with the use of this device has been recently described.3 Massive pulmonary emboli was the most frequent indication (42%), followed by right atrial vegetation or thrombus and vena caval thrombus. The overall success rate of aspiration and clot removal in the series was 79%.
Our acknowledgement to the cardiology medical team.