Faculty Bibliography

Upper hemi-sternotomy is a common approach for outflow graft anastomosis to the ascending aorta in minimally invasive left-ventricular assist device implantation. Right mini-thoracotomy may also be used, but use of robotic assistance has been reported only anecdotally. The aim of our study was to confirm the feasibility of robotically assisted suturing of the outflow graft anastomosis and to assess performance metrics for the robotic suturing part of the procedure. The procedure was carried out in eight cadaver studies by two surgeons. The assist device pump head was inserted through a left-sided mini-thoracotomy and the outflow graft was passed toward a right-sided second interspace mini-thoracotomy through the pericardium. After placement of a partial occlusion clamp on the ascending aorta, a longitudinal aortotomy was performed and the outflow graft to ascending aorta anastomosis was carried out robotically. The procedure was feasible in all eight attempts. The mean outflow graft anastomotic time was 20.1 (SD 6.8) min and the mean surgeon confidence and comfort levels to complete the anastomoses were 8.3 (SD 2.4) and 6.9 (SD2.2), respectively, on a ten-grade Likert scale. On open inspection of the anastomoses, there was good suture alignment in all cases. We conclude that suturing of a left-ventricular assist device outflow graft to the human ascending aorta is very feasible with good surgeon comfort. Anastomotic times are acceptable and suture placement can be performed with appropriate alignment.

Andexanet alfa was employed to reverse the anticoagulant effect of direct oral anticoagulants in 3 patients who required emergent surgery for repair of type A aortic dissection. Its use was instrumental in securing haemostasis. However, we caution against the administration of Andexanet alfa prior to cardiopulmonary bypass as it can induce heparin resistance and complicate the perioperative monitoring of anticoagulation during cardiopulmonary bypass.

Severe coronary artery disease is associated with disproportionately increased risks of death in patients with hypertrophic cardiomyopathy. There is a paucity of data on the long-term effect of coronary revascularization at the time of myectomy. Between January 1, 1961, and October 31, 2017, 2913 adult patients underwent transaortic septal myectomy at Mayo Clinic. Concomitant coronary artery bypass grafting (CABG) was performed in 246 (8.4%). We compared baseline characteristics of patients who underwent septal myectomy with and without CABG and assessed the effect of surgical revascularization on the risk of all-cause mortality. Patients who underwent concomitant CABG were older (median [interquartile range], 66.3 [59.8-72.1] years vs 54.4 [43.5-64.8] years; P<.0001) and more likely to be male (63.0% vs 54.2%; P=.008) than those who did not undergo coronary revascularization at operation. There was no significant difference in preoperative left ventricular outflow tract gradients (55 [25-81] mm Hg vs 58 [25-88] mm Hg; P=.116). Overall operative mortality (≤30 days after surgery) was 1.0% and higher in patients who underwent concomitant CABG (2.2% vs 0.8%; P=.048). In multivariable analysis (n=2641), factors independently associated with mortality included concomitant CABG (hazard ratio [95% CI], 1.89 [1.39-2.58]; P<.0001), older age at operation (per interquartile range increase, 2.79 [1.95-3.98]; P<.0001), atrial fibrillation (1.46 [1.11-1.92]; P=.006), diabetes (1.45 [1.04-2.04]; P=.031), higher body mass index (change from 0.95 to 0.5 quantile, 1.95 [1.46-2.59]; P<.0001), and surgery performed earlier in the study period (2.02 [1.31-3.11]; P=.001). In conclusion, obstructive coronary artery disease severe enough to prompt concomitant CABG at the time of septal myectomy is an important risk factor for late mortality.

OBJECTIVE:Published data are limited in comparison of transcatheter aortic valve replacement with surgical aortic valve replacement for the failing aortic root homograft. We reviewed our experience with repeat aortic valve replacement in failing aortic root homografts to compare outcomes of transcatheter aortic valve replacement and surgical aortic valve replacement. METHODS:We retrospectively reviewed the records of 51 patients with failing aortic root homografts who received repeat aortic valve replacement between October 2000 and May 2018. Operation included transcatheter aortic valve replacement in 11 patients between June 2014 and May 2018. Surgical aortic valve replacement was performed in 40 patients between October 2000 and January 2018, and operation included repeat composite aortic valve/root replacement in 30 patients (75%). RESULTS:Patient age was 59 years (interquartile range, 50-72 years), sex was female in 9 patients (18%), and time to repeat aortic valve replacement was 12 years (interquartile range, 8-13). Procedure-related complications occurred in 37 patients (73%): vascular injury (any) more commonly in the transcatheter aortic valve replacement group (36% vs 5%; P = .015), bleeding (major or life-threatening) more commonly in the surgical aortic valve replacement group (58% vs 0%; P < .001), and sternal reentry injury only in the surgical aortic valve replacement group (n = 6, 15%). There were 3 procedure-related deaths in the surgical aortic valve replacement group (8%) and 1 (9%) in the transcatheter aortic valve replacement group (P = 1.000). Subsequent cardiac operation occurred in no patients in the transcatheter aortic valve replacement group and in 5 patients in the surgical aortic valve replacement group. CONCLUSIONS:Repeat aortic valve replacement for failing aortic root homograft is associated with notable risk of morbidity and mortality regardless of replacement technique. Avoidance of vascular injury could lead to improved outcomes in the transcatheter aortic valve replacement group.

BACKGROUND:This study directly compared outcomes of transcatheter aortic valve-in-valve insertion (TAVI-in-valve) with repeat surgical aortic valve replacement (SAVR) for failing stented aortic biological prostheses. METHODS:We retrospectively reviewed the records of 350 consecutive patients who underwent repeat aortic valve replacement of failing stented aortic biological valve prostheses at our institution between November 2008 and May 2018. Operations included TAVI-in-valve in 90 patients (26%) and repeat SAVR in 260 patients (74%). RESULTS:Patient age was 74 years (interquartile range [IQR], 65-79 years), 100 patients (29%) were women, aortic valve internal diameter was 21 mm (IQR, 19-22), Society of Thoracic Surgeons predicted operative mortality risk was 4.1% (IQR, 2.3%-6.8%), and the interval to repeat operation was 7 years (IQR, 5-11 years). A 23-mm or smaller valve was inserted in 57 patients (63%) in the TAVI-in-valve group and in 170 (65%) in the SAVR group (P = .725). Aortic root enlargement was done in 45 patients (17%) in the SAVR group. Procedure-related complications were less in the TAVI-in-valve group (23% vs SAVR 59%, P < .001), whereas operative mortality was similar in both groups (2.2% vs SAVR 2.6%, P = 1.000). Severe patient-to-prosthesis mismatch was more common after TAVI-in-valve (44% vs SAVR 12%, P < .001). Median duration of follow-up was 2.1 years (IQR, 1.2-4.2 years). Multivariable analysis demonstrated no association between TAVI-in-valve and intermediate-term mortality (hazard ratio, 1.18; 95% confidence interval, 0.62 to 2.22; P = .612). CONCLUSIONS:TAVI-in-valve and repeat SAVR can be done with similar operative and intermediate-term mortality. SAVR results in better hemodynamic function and thus appears the preferred option.