Faculty Bibliography

OBJECTIVE: In patients with atrial fibrillation, 90% of embolic strokes originate from the left atrial appendage (LAA). Successful exclusion of the LAA is associated with a lower stroke rate in patients with atrial fibrillation. Surgical oversewing of the LAA is often incomplete when evaluated with transesophageal echocardiogram (TEE). External closure techniques of suturing and stapling have also demonstrated high failure rates with persistent flow and large stumps. We hypothesized that the precise visualization of a robotic LAA closure (RLAAC) would result in superior closure rates. METHODS: Before robotic mitral repair, patients underwent RLAAC; the base of the LAA was oversewn using a running 4-0 polytetrafluoroethylene suture in two layers. Postoperatively, the LAA was interrogated in multiple TEE views. Incomplete closure was defined as any flow across the LAA suture line or a residual stump of greater than 1 cm. RESULTS: Seventy-nine consecutive patients underwent RLAAC; no injuries occurred. On postrepair TEE, 73 of 79 patients had LAAs visualized well enough to thoroughly evaluate. Successful ligation was confirmed in 64 (87.7%) of 73 patients. Seven patients (9.6%) had small jet flow into the LAA; no residual stumps were noted. Two patients (2.7%) had undetermined flow. CONCLUSIONS: We have demonstrated excellent success with RLAAC; we postulate that this may be due to improved intracardiac visualization. Robotic LAA closure was more successful (87.7%) than previously reported results from the Left Atrial Appendage Occlusion Study for suture exclusion (45.5%) and staple closure (72.7%). With success rates equivalent to transcatheter device closures, RLAAC should be considered for robotic mitral valve surgical patients.

BACKGROUND: Recurrent mitral regurgitation after mitral valve repair is common, occurring in nearly 50% of patients within 10 years of surgery. Durability of repair is partly related to stress distribution over the mitral leaflets. We hypothesized that repair with neochords (NCs) results in lower stress than leaflet resection (LR). MATERIALS AND METHODS: Magnetic resonance imaging and 3D echocardiography were performed before surgical repair of P2 prolapse in a single patient. A finite element model of the left ventricle and mitral valve was created previously, and the modeling program LS-DYNA was used to calculate leaflet stress for the following repairs: Triangular LR; LR with ring annuloplasty (LR + RA); One NC; Two NCs; and 2NC + RA. RESULTS: (1) NC placement resulted in stable posterior leaflet stress: Baseline versus 2 NC at end diastole (ED), 12.1 versus 12.0 kPa, at end systole (ES) 20.3 versus 21.7 kPa. (2) In contrast, LR increased posterior leaflet stress: Baseline versus LR at ED 12.1 versus 40.8 kPa, at ES 20.3 versus 46.1 kPa. (3) All repair types reduced anterior leaflet stress: Baseline versus 2 NC versus LR 34.2 versus 25.8 versus 20.6 kPa at ED and 80.8 versus 76.8 versus 67.8 kPa at ES. (4) The addition of RA reduced leaflet stress relative to repair without RA. CONCLUSIONS: Neochord repair restored normal leaflet coaptation without creating excessive leaflet stress, whereas leaflet resection more than doubled stress across the posterior leaflet. The excess stress created by leaflet resection was partially, but not completely, mitigated by ring annuloplasty.

This monograph outlines the rich history of cardiothoracic surgery at New York University (NYU), beginning with its origins at The Bellevue Hospital in the mid-1800's. Numerous early clinical accomplishments were significant, leading up to the arrival of Dr Frank Spencer in 1966. Under Dr Spencer's leadership, the department progressed with development of a culture of innovation, leadership and education that carries through today. The program encompasses three major hospitals and will soon graduate its 50th class of trainees, many of whom have had outstanding careers and a major impact on the field of cardiothoracic surgery. This culture continues under the direction of our current chair, Dr Aubrey Galloway, whose vision has orchestrated and refined a new period of innovation and excellence.

OBJECTIVE: The recent development of the EDWARDS INTUITY Elite (EIE) valve system enables the rapid deployment of a prosthetic surgical heart valve in an aortic valve replacement (AVR) procedure via both the minimally invasive (MISAVR) and conventional (CAVR) approaches. In order to understand its economic value, this study performed a cost evaluation of the EIE valve system used in a MIS rapid-deployment approach (MIS-RDAVR) vs MISAVR and CAVR, respectively, compared to standard prosthetic aortic valves. METHODS: A simulation model was developed using TreeAge (and validated with MS Excel) to compare the inpatient utilization and complication costs for each treatment arm. Thirty-day clinical end-points for the MIS-RDAVR (mortality and complications) were taken from the TRANSFORM trial; and a best evidence review of the published literature was used for the MISAVR and CAVR approaches. Studies were pooled and parameter estimates were weighted by sample size in order to compare the TRANSFORM patients. Cost data (2016 USD) were taken from the Premier database. Incremental cost and cost-effectiveness was assessed and one-way/probabilistic sensitivity analyses performed to gauge the robustness of the results. RESULTS: MIS-RDAVR costs $2,621 less than CAVR and had lower mortality rates, making it a superior (dominant) technology relative to CAVR. MIS-RDAVR costs $4,560 more than MISAVR, but was associated with an additional 0.20 life years-per-patient. This implies a cost-effectiveness ratio of $22,903 per-life-year-gained. Thus, MIS-RDAVR is cost-effective compared to MISAVR. CONCLUSIONS: The EIE valve system deployed in a MIS approach appears to be a cost-effective technology compared to MISAVR and CAVR. When compared to CAVR it may achieve cost savings as well. These results suggest that MIS-RDAVR confers superior economic value compared to both standard MISAVR and CAVR via lowered key complication rates (re-operation, renal complications, wound infection, TIA, endocarditis) and utilization (cross-clamp time, hospital ward days).

Widespread adoption of minimally invasive mitral valve repair and replacement may be fostered by practice consensus and standardization. This expert opinion, first of a 3-part series, outlines current best practices in patient evaluation and selection for minimally invasive mitral valve procedures, and discusses preoperative planning for cannulation and myocardial protection.

Minimally invasive mitral valve operations are increasingly common in the United States, but robotic-assisted approaches have not been widely adopted for a variety of reasons. This expert opinion reviews the state of the art and defines best practices, training, and techniques for developing a successful robotics program.

Techniques for minimally invasive mitral valve repair and replacement continue to evolve. This expert opinion, the second of a 3-part series, outlines current best practices for nonrobotic, minimally invasive mitral valve procedures, and for postoperative care after minimally invasive mitral valve surgery.