RP26. Repair of Massive Pulmonary Arterial Aneurysm and Dissection with Concomitant Severe Pulmonary Arterial Hypertension and Right Ventricular Dysfunction with Novel Intrapulmonary Arterial Balloon Pump.

Background:
A 57-year-old woman with WHO Group 1 PAH, RV dysfunction, and BMI of 44 presented with progressively enlarging aneurysms of the main (7.8cm) and bilateral PAs complicated by dissection. She was ineligible for definitive heart-lung transplantation due to her BMI. Therefore, she underwent high-risk repair of the pulmonary arteries, including novel deployment of an intrapulmonary arterial balloon pump (IPBP) to mitigate severe perioperative RV dysfunction.

Case:
A median sternotomy was performed, CPB was instituted with aortic and bicaval cannulation. Massive aneurysms of the main and bilateral PAs were resected, including a dissection originating from the MPA extending into the LPA. A 30mm Hemashield graft with an 8mm sidearm was sewn end-to-end to the LPA and RPA; The dysmorphic pulmonic valve was excised, and a composite valve graft (CVG) was constructed with a 27mm Magna Edwards aortic valve within a 30mm Hemashield graft with an 8mm sidearm. The CVG was implanted into the pulmonic root followed by an end-to-side anastomosis to the replaced L and RPA graft. Each of the two 8mm sidearms off the replaced RPA and MPA were extended with additional grafts and tunneled through the chest wall for IPBP and possible RVAD support. An IPBP was inserted via the tunneled RPA sidearm to the MPA under TEE guidance and initiated 1:1 with a maximum volume of 26cc. CPB duration was 311 minutes with no cardioplegic arrest required. On postoperative day 4, the IPBP was removed via the tunneled graft, which was thoroughly sterilized, stapled, and divided under mild tension to allow retraction into the chest. On postoperative day 5, the patient developed recurrent episodes of SVT and acute RV failure secondary to fluid overload. An oxygenated RVAD was placed via a percutaneous right femoral venous cannula and the second tunneled graft to the MPA for pulmonary arterial return. On postoperative day 18 the second tunneled graft was decannulated and internalized after sterilization and division. Three months after the index operation, the patient was transferred to a rehabilitation unit at her local hospital.

Conclusion:
In patients with RV dysfunction undergoing PA reconstruction, grafts tunneled through the chest wall provide a novel access strategy to mechanically support the RV. Intrapulmonary arterial counterpulsation may offload the RV, thereby reducing the work and myocardial oxygen demand required of the dysfunctional RV, augmenting cardiac output.

Stefan Elde (1), Avi Gupta (1), John McNulty (1), Brandon Guenthart (1), Yasuhiro Shudo (1), Elan Burton (1), Y. Joseph Woo (1), (1) Stanford University, Palo Alto, CA

Stefan Elde

Poster Presenter

Dr. Stefan Elde is a PGY4 integrated cardiothoracic surgery resident at Stanford University. He is currently in the first of three years as a postdoctoral research fellow in the lab of Y. Joseph Woo, Norman E. Shumway Professor and Chair of the Department of Cardiothoracic Surgery. His basic science research focuses on utilizing spatial biology techniques to study angiogenesis and myocardial regeneration in small and large mammals. He is also involved in bioengineering research using the lab's novel left-heart simulator to investigate the optimization of mitral and aortic valve repair techniques. Dr. Elde's clinical research focuses on surgery of the mitral valve as well as heart & lung transplantation.