Persistent Left Superior Vena Cava in Heart Transplantation

Abstract

Persistent left superior vena cava is the most common thoracic venous abnormality seen in heart surgery. Previous case reports describe the surgical technique for reimplantation of PLSVC during transplantation but do not describe midterm patency. We describe our technique for PLSVC anastomosis and postoperative management with midterm data, both intraprocedural details and postoperative direct oral anticoagulation therapy.

Graphical Abstract

Persistent left superior vena cava (PLSVC) occurs in 0.3% of the general population and up to 5% of patients with congenital abnormalities.^1,2 PLSVC is usually asymptomatic, but it may lead to conduction abnormalities (eg, atrial fibrillation) and may lead to hemodynamic complications with long-term heart failure.^1,3 Technical considerations should be made in patients considered for heart transplant with concomitant PLSVC. A dilated coronary sinus seen on echocardiography or absent innominate vein on computed tomography should further suspicion of PLSVC.³ Identifying PLSVC is crucial to prevent catheter-related complications, as thrombus in the coronary sinus can obstruct the 20% of venous blood return from the left arm and head that drains through the PLSVC.² Different complications such as coronary sinus atresia may cause the PLSVC to become a retrograde passage of drainage from the coronary vessels, leading to right atria dilation.¹ Previous studies describe surgical techniques for reattachment during transplantation, such as in situ conduit from coronary sinus tissue, donor pericardium, 10 mm polytetrafluorethylene (PTFE) graft anastomosis to right atrial appendage (RAA), end-to-end anastomosis of native PLSVC to the superior vena cava, and end-to-side anastomosis of the recipient innominate vein to the donor superior vena cava.3, 4, 5, 6, 7 Here, we consider 2 cases in which a 14 mm PTFE graft was used for proper venous drainage of PLSVC during transplantation, describing long-term patency with midterm follow-up using a direct oral anticoagulant regimen (DOAC).

Take-Home Messages

• •In patients with PLSVC undergoing heart transplantation, the use of a 14 mm PTFE graft for anastomosis to the right atrial appendage, combined with a DOAC regimen, demonstrated successful midterm patency in 2 patients, preventing thromboembolic complications.
• •Our findings highlight the importance of early identification of PLSVC, meticulous surgical planning, and consistent anticoagulation to ensure optimal post-transplant outcomes.

Case Report

Patient 1

A 19-year-old man presented with acute onset cardiogenic shock and bilateral ventricular dysfunction with left ventricular thrombus and dilated left ventricle. The patient was transferred for heart catheterization, where cardiogenic shock was managed with a mechanical circulatory support device (Impella 5.5; Abiomed) as a bridge into transplantation after resolution of thrombus was visualized. Heart transplantation was recommended because of bilateral ventricular dysfunction and worsening cardiogenic shock. Cyclic fevers were observed, and the etiology was myocarditis as confirmed by positron emission tomography scan. During scans, PLSVC was noted, as shown in Figure 1.

Figure 1.

Preoperative Imaging of PLSVC in Patient 1

Preoperative scans of patient 1’s persistent left superior vena cava (PLSVC) as it runs in its normal anatomic course anterior to the left pulmonary artery. Coronal view (A) and axial view (B). The asterisks indicate the PLSVC.

Patient 2

A 39-year-old woman presented with acute on chronic cardiogenic shock and heart failure. The patient had congenital membranous ventricular septal defect treated with pulmonary banding. Owing to left anterior descending artery injury during the procedure, she was left with ischemic cardiomyopathy (heart failure with reduced ejection fraction of 25%). The patient had a known PLSVC (shown on scans in Figure 2), with a history of paroxysmal atrial fibrillation, automatic implantable cardioverter-defibrillator placement, tricuspid valve repair, ventricular tachycardia, left ventricular aneurysm repair, and pulmonary hypertension. The patient also had previous epicardial ablations and paroxysmal atrial fibrillations that were treated with a maze procedure.

Figure 2.

Preoperative Imaging of PLSVC in Patient 2

Preoperative course of the persistent left superior vena cava (PLSVC) with coronal views (A and B) and axial views (C and D). The left ventricular lead of the biventricular pacer is seen going through the PLSVC in these images. The asterisks and red arrows indicate the PLSVC.

Operative Technique

We describe 2 cases of successful orthotopic heart transplantation with anastomosis of PLSVC and no perioperative complications. The technical components of these cases were identical and are shown in Figure 1, Figure 2. After recipient cardiectomy, PLSVC was transected after entrance into the mediastinum. The first step was to sew a 14 mm PTFE graft to the PLSVC via end-to-side fashion (Figure 3A). After anastomosis completion, a cardiotomy pump sucker was used to decompress the PLSVC, allowing drainage away from the field (Figure 3B). After standard bicaval heart transplantation, we coursed the graft behind the heart (Figure 3C), where the ring PTFE came back up at the level of the inferior vena cava and was attached in a U-pattern onto the RAA with a 4.0 prolene suture (shown in Figure 3D). Both patients were maintained on a regular biopsy schedule through the right internal jugular vein and were discharged on standard triple immunosuppressant therapy. The patients were initially started on aspirin 81 mg on day 1, with a heparin bridge on postoperative day 2. They were discharged on apixaban 2.5 mg twice daily and were maintained on standard immunosuppression and DOAC. Patient 1 was maintained on apixaban and was weaned off aspirin at 1 year post-transplantation, and patient 2 has remained on aspirin and apixaban owing to a later kidney transplant. The average duration of follow-up was 2.6 years.

Figure 3.

PLSVC Anastomosis

(A) Persistent left superior vena cava (PLSVC) anastomosis to 14 mm polytetrafluorethylene (PTFE) graft. (B) Cardiotomy pump suction drainage for PLSVC during procedure. (C) PTFE graph after anastomosis. Standard bicaval transplantation with graft coursed behind heart. (D) Completed anastomosis with PLSVC reimplantation into right atrial appendage. The asterisks indicate the 14 mm PTFE conduit, the blue arrows indicate the PLSVC anastomosis, and the yellow arrow indicates the anastomosis into the right atrial appendage.

Discussion

PLSVC poses difficulty during transplantation. We found success in the midterm patency using a 14 mm PTFE graft to reroute the PLSVC onto the RAA. The limited cases of PLSVC in heart transplantation highlight the need for ongoing patient monitoring and documentation of future patients to refine the surgical technique. The difference between our technique and previous reports is that these 2 patients were monitored over the course of over 2 years to provide midterm data supporting our management option. Other studies have used different techniques, and only 1 study reported midterm data on a single patient using a biatrial anastomosis in comparison to a bicaval technique, in which there were no major complications at 2.5 years post-transplantation using aspirin without warfarin.³ A second study used a PTFE graft of a different size (10 mm) and reported 2-year patency with no venostasis-related symptoms, using warfarin as anticoagulation.⁶

Biatrial heart transplantations can have negative side effects, including conduction disruptions (eg, arrhythmias), therefore we chose the bicaval transplantation technique with the aim to preserve anastomotic connections. While 2 transplantation techniques may be used in this procedure, bicaval was chosen, as it is the preferred technique in that there is less arrythmia and tricuspid regurgitation and better overall heart function and long-term survival with this technique. Specifically, the preserved right atrial geometry helps maintain tricuspid valve function, which has frequently been a post-transplantation complication. With restored left ventricular function, this is the preferred method.⁸ The 14 mm PFTE graft was used as a safe conduit to connect the PLSVC to the atria, especially when required to lengthen the vessel.

In a patient with PLSVC, early identification is critical to determine venous return during bypass. Some complications that may occur when using a graft include thrombosis and obstruction in the graft, which can be prevented by continuous use of anticoagulants. Both of our patients maintained the DOAC regime using apixaban and aspirin in the first year post-transplantation, when there is the greatest risk of complication. The need for anticoagulation was used for 1 year and benefits the long-term management of atrial arrythmias and heart function, especially with venous reconstruction, as we bridged the PLSVC. A cardiotomy pump was used as an unabated method of decompression to bypass gravity, which was chosen because of the significant lack of negative effects with good visual field. Using the cardiotomy pump for continuous drainage preserves lower venous pressure, a critical methodological consideration owing to profound drainage into the PLSVC.

Conclusions

It is crucial to consider PLSVC in heart transplantation, as it should be addressed early in the procedure for uninterrupted venous drainage, setting up procedural success.^1,2 In patients with PLSVC, a successful transplant includes meticulous surgical planning and execution for longstanding positive results. In both of our patients, PLSVC was effectively managed by constructing a conduit for anastomosis to the RAA using a 14 mm ringed PTFE graft. Our operative technique required an organized plan to ensure proper hemodynamics throughout the procedure. We believe the use of a standard DOAC regimen using apixaban and aspirin were important adjuncts in addition to the surgical technique. The DOAC regimen has been integral to the postoperative management, ensuring patency of the anastomosis and preventing thromboembolic complications. The midterm outcomes are promising: In our cases, at 2.3 and 3.2 years post-transplantation, both patients have patent grafts with no procedure-related complications. The encouraging midterm patency and lack of complications from this approach offers valuable insight into the management of PLSVC with a recommended DOAC regimen for best results.

Funding Support and Author Disclosures

The authors have reported that they have no relationships relevant to the contents of this paper to disclose.