The patient was a 59-year-old man who had undergone aortic valve replacement with a mechanical valve for aortic stenosis eight years ago. Six months ago, he developed complete atrioventricular block and underwent pacemaker implantation. One day before admission, he presented to a local clinic with complaints of dyspnea and chest pain. Suspecting acute myocardial infarction, he was referred to our hospital for further evaluation and was subsequently admitted. On admission, he exhibited fever and elevated inflammatory markers. Transthoracic echocardiography and computed tomography revealed vegetations on the prosthetic valve and an annular abscess with aneurysmal dilatation of the sinus of Valsalva. Based on these findings, prosthetic valve endocarditis was diagnosed, and semi-urgent surgery was performed. Intraoperatively, numerous vegetations were found attached to the prosthetic valve annulus, and the annular abscess had extensively invaded the myocardium circumferentially. Aneurysmal dilatation of the sinus of Valsalva was observed, especially around the left and right commissures. After debridement of the abscess cavity, it was determined that Bentall procedure was not feasible due to extensive annular destruction and fragility of the surrounding myocardial tissue. Therefore, we opted for a root reconstruction using the “graft insertion technique” as described by Nakamura et al. A 5-cm length of tube graft was inverted and inserted from the aortic root into the left ventricular outflow tract (LVOT). Nine mattress sutures using 3-0 polypropylene with pledgets were placed from inside the graft through the LVOT, with external reinforcement using a Teflon felt strip, followed by continuous suturing for added security. The intraventricular portion of the graft was pulled out through the LVOT and trimmed. A preconstructed composite graft was then anastomosed to the trimmed end. The right coronary artery was reimplanted using the button technique. The left coronary artery was injured during dissection of adhesion and could not be reimplanted; therefore, a bypass from the great saphenous vein to the left anterior descending artery was performed. Despite the loss of healthy annular tissue due to complete debridement of the infected valve and myocardial abscess, the reconstruction of the aortic root was successful without the need for additional hemostatic sutures. The “graft insertion technique，” though not yet widely established, offers a valuable approach for reconstructing severely damaged and fragile aortic roots in the setting of prosthetic valve endocarditis. It allows for safe and reliable surgical repair even in challenging anatomical conditions.

Purpose: Determination of optimal treatment strategies for HER2-positive advanced gastric cancer (AGC) in randomized trials is necessary despite difficulties in direct comparison between trastuzumab deruxtecan (T-DXd) and nivolumab as third or later-line treatments. Materials and Methods: This single-institution, retrospective study aimed to describe the real-world efficacy and safety of T-DXd and nivolumab as ≥ third line treatments for HER2-positive AGC between March 2016 and May 2022. Overall, 58 patients (median age, 64 years;69% male) were eligible for the study (T-DXd group, n=20; nivolumab group, n=38). Results: Most patients exhibited a HER2 3+ status (72%) and presented metastatic disease at diagnosis (66%). The response rates of 41 patients with measurable lesions in the T-DXd and nivolumab groups were 50% and 15%, respectively. The T-DXd and nivolumab groups had a median progression-free survival of 4.8 months (95% confidence interval [CI], 3.3, 7.0) and 2.3 months (95% CI, 1.5, 3.5), median overall survival (OS) of 10.8 months (95% CI, 6.9, 23.8) and 11.7 months (95% CI, 7.6, 17.1), and grade 3 or greater adverse event rates of 50% and 2%, respectively. Overall, 64% patients received subsequent treatment. Among 23 patients who received both regimens, the T-DXd–nivolumab and nivolumab–T-DXd groups had a median OS of 14.0 months (95% CI, 5.0, not reached) and 19.3 months (95% CI, 9.5, 25.1), respectively. Conclusions T-DXd and nivolumab showed distinct efficacy and toxicity profiles as ≥ third line treatments for HER2-positive AGC. Considering the distinct features of each regimen, they may help clinicians personalize optimal treatment approaches for these patients.