Robot-Assisted Aortic Valve Replacement　- First Clinical Report in Japan.

BACKGROUND: Robot-assisted valve surgery represents the latest development in the field of minimally invasive approaches. Robotic assistance may provide greater visualization, enhanced dexterity, and greater precision than traditional mini-thoracotomy aortic valve replacement.Methods and Results: Aortic valve replacement operations using the da Vinci Xi Surgical System (Intuitive Surgical Inc., Sunnyvale, CA, USA) were performed on 2 patients, 1 with severe aortic insufficiency and the other with aortic stenosis. Both patients had an uneventful postoperative course and were discharged without any adverse events. CONCLUSIONS: Robot-assisted assisted aortic valve replacement appears feasible and safe in limited cases.

Safe launch of a robotically assisted mitral valve repair program in a single center: experience of initial 20 cases under the Center for Minimally Invasive Surgery.

Robotically assisted mitral valve repair was approved by the Japanese government in April 2018. However, understanding robotic surgery involves steep learning curves of surgeons and dedicated cardiac teams. The Center for Minimally Invasive Surgery (CMIS) of Tottori University Hospital is a multidisciplinary organization established in 2011 with seven surgical departments. In this study, we report strategies for improving the safety of robotic surgery in the CMIS and early results of robotic mitral valve repair at our hospital. We reviewed the first 20 patients who underwent robotic primary mitral valve repair, including concomitant procedures, from October 2019 to September 2021 under the supervision of the CMIS. Before starting the program, the CMIS requires setting console time limit to 180 min and implementing risk management strategies through simulation training for various mechanical failures. Mitral valve repair was completed in all patients. There was no in-hospital or 30-day mortality. No conversion to median sternotomy was necessary. The analysis of mitral pathology revealed 1 case of functional mitral regurgitation, 12 cases of posterior lesions, 3 cases of anterior lesions, 3 cases of bileaflet lesions, and 1 case of commissural lesion. The average cross-clamp time was 133 ± 27 min. Sixteen cases had trace mitral regurgitation postoperatively, and 4 cases had mild mitral regurgitation. The median (interquartile range) postoperative hospital stay was 10 (8.5-12.5) days. Robotically assisted mitral valve repair was performed safely with assistance from the multidisciplinary CMIS, and the early results were satisfactory without compromising clinical outcomes.

Impact of frailty on early and mid-term outcomes of hybrid aortic arch repair.

PURPOSE: The purpose of this study was to investigate the impact of frailty on the clinical outcomes of hybrid aortic arch repair with debranching of the supra-aortic arteries. METHODS: Consecutive patients ≥ 75 years old who underwent hybrid aortic arch repair from January 2010 to December 2019 were retrospectively analyzed. Using the Canadian Study of Health and Aging (CSHA) scale, all patients with a CSHA scale score > 4 were defined as frail. The frail patients (FP) group and the non-frail patients (NFP) group were compared regarding the early and mid-term outcomes of hybrid aortic arch repair. RESULTS: A total of 84 patients were included. The early postoperative results were not markedly different between the groups, except that the rate of transfer to a rehabilitation hospital was higher in the FP group than in the NFP group. The survival at 5 years was significantly lower in the FP group at 43.0% than in the NFP group at 67.7% (P = 0.015). However, the freedom from aorta-related death was not significantly different between the two groups. CONCLUSION: Frailty did not affect the short-term outcomes of hybrid aortic arch repair; however, the mid-term outcomes, including the survival, of the frail patients were significantly worse than those of the non-frail patients, mostly because of non-aorta-related causes.

Debranching thoracic endovascular aortic repair for distal aortic arch aneurysm in elderly patients aged over 75 years old.

BACKGROUND: We examined the outcome of debranching thoracic endovascular aortic repair (d-TEVAR) without sternotomy for distal aortic arch aneurysm in patients aged ≥75 years. METHODS: Patients who underwent d-TEVAR or TAR for aortic arch aneurysm between 2008 and 2015 at our hospital and aged ≥75 years were included. Age, sex, left ventricular ejection fraction, preoperative creatinine level, diabetes, cerebrovascular disease, and chronic obstructive pulmonary disease were matched using PS. RESULTS: Among 74 patients (d-TEVAR: 51, TAR: 23), 17 patients in each group were matched. No difference in surgical outcome was detected between the d-TEVAR and TAR groups, including 30-day death (0% vs. 0%), hospital death (5.8% vs. 0%: p = 0.31) and incidence of cerebral infarction (5.8% vs. 7.6%: p = 0.27) as well as the long-term outcomes of 5-year survival (92.8% vs. 74.8%: p = 0.30) and 5-year aorta-related event-free rate (88.2% vs. 100%: p = 0.15). Average duration of ICU stay (1.3 ± 1.1 days vs. 5.6 ± 1.3 days: p = 0.025) and hospital stay (16.5 ± 5.2 days vs. 37.7 ± 19.6 days: p = 0.017) were significantly shorter in the d-TEVAR group. CONCLUSION: Our results indicated that d-TEVAR is less invasive without affecting long-term outcome up to 5 years. Although the number of the patients included in the study was small, debranching TEVAR could be one of the treatments of the choice in the elderly, especially with comorbidities.

Tolvaptan can limit postoperative paroxysmal atrial fibrillation occurrence after open-heart surgery.

PURPOSE: Tolvaptan administration in the early postoperative period after cardiac surgery rapidly treats fluid retention without affecting the renal function. Tolvaptan also has the benefit of not stimulating the renin-angiotensin and sympathetic nervous systems, which are risk factors for postoperative paroxysmal atrial fibrillation. In this study, we examined the hypothesis that tolvaptan administration reduces postoperative paroxysmal atrial fibrillation and worsening of the renal function incidence in patients who have undergone open-heart surgery. METHODS: From our previous randomized study, we selected 166 open-heart surgery patients, divided them into 2 groups [tolvaptan group, 83 patients; control (non-tolvaptan) group, 83 patients], and compared the incidence of postoperative paroxysmal atrial fibrillation and worsening of the renal function in the postoperative period between the groups. RESULTS: The incidence of worsening of the renal function was significantly lower in the tolvaptan group than in the control group (4.8% vs. 15.7%; P = 0.04). The incidence of postoperative paroxysmal atrial fibrillation within 14 days was also significantly lower in the tolvaptan group than in the control group (26.5% vs. 42.2%; P = 0.011). CONCLUSION: Tolvaptan administration in the early postoperative period after open-heart surgery may reduce the incidence of postoperative paroxysmal atrial fibrillation and worsening of the renal function.

Can Tolvaptan Protect Renal Function in the Early Postoperative Period of Cardiac Surgery?　- Results of a Single-Center Randomized Controlled Study.

BACKGROUND: Oral administration of tolvaptan, a vasopressin V2receptor antagonist, significantly reduces deterioration of renal function, which has recently been highlighted as an exacerbating factor for adverse events in patients with acute heart failure. In the present study we tested the hypothesis that concomitant administration of tolvaptan with a conventional diuretic is beneficial for perioperative body fluid management in patients who have undergone cardiac surgery.Methods and Results:In all, 280 patients who underwent cardiac surgery were prospectively randomized to concomitant treatment with tolvaptan and a conventional diuretic (tolvaptan group; 147 patients) or treatment with a conventional diuretic alone (control group; 133 patients). Groups were compared in terms of the time required to restore preoperative body weight and the incidence of worsening renal function (WRF), defined as an increase in the serum creatinine level ≥0.3 mg/dL. The time required to restore preoperative body weight was significantly shorter in the tolvaptan than control group (mean [±SD] 3.97±1.95 vs. 5.02±2.83 days, respectively; P<0.001). The incidence of WRF was significantly lower in the tolvaptan than control group (n=11 [7.5%] vs. n=25 [18.8%], respectively; P=0.011). CONCLUSIONS: Administration of tolvaptan with conventional diuretics in the early postoperative period after cardiac surgery could be beneficial in maintaining urine output without affecting renal function and may thus help avoid WRF.

Smooth muscle cell sheet transplantation preserve cardiac function and minimize cardiac remodeling in a rat myocardial infarction model.

BACKGROUND: We examined whether a vascular smooth muscle cell (SMC) sheet is effective in the treatment of a rat myocardial infarction (MI) model. METHODS: We examined the effect of SMC sheet on the cardiac function and cardiac remodeling in a rat MI model in comparison with their effect of dermal fibroblast (DFB) sheet in vivo. Furthermore, we estimated the apoptosis and secretion of angiogenic factor of SMC under hypoxic condition in comparison with DFB. Seven days after MI, monolayer cell sheets were transplanted on the infarcted area (SMC transplantation group, SMC-Tx; DFB transplantation group, DFB-Tx; no cell sheet transplantation group, Untreated; neither MI nor cell sheet transplantation group, Sham). We evaluated cardiac function by echocardiogram, degree of cardiac remodeling by histological examination, and secretion of angiogenic growth factor by enzyme immunoassay. RESULTS: Twenty-eight days after transplantation, SMC-Tx showed the following characteristics compared with the other groups: 1) significantly greater fractional area shortening (SMC-Tx, 32.3 ± 2.1 %; DFB-Tx, 23.3 ± 2.1 %; untreated, 25.1 ± 2.6 %), 2) suppressed left ventricular dilation, smaller scar expansion, and preserved wall thickness of the area at risk and the posterior wall, 3) decreased fibrosis, preserved myocardium in the scar area, and greater number of arterioles in border-zone, 4) tight attachment of SMC sheets on the scarred myocardium, and less apoptotic cell death. In in vitro experiments, SMCs secreted higher amounts of basic fibroblast growth factor (SMC, 157.7 ± 6.4 pg/ml; DFB, 3.1 ± 1.0 pg/ml), and showed less apoptotic cell death under hypoxia. CONCLUSIONS: Our results illustrate that transplantation of SMC sheets inhibited the progression of cardiac remodeling and improve cardiac function. These beneficial effects may be due to superior SMC survival.

Effect of tiopronin on excretion of homocysteine and its plasma exposure level in rats.

When the biosynthesis of homocysteine (Hcy), an amino acid containing thiol, exceeds its elimination, plasma Hcy concentration increases and results in hyperhomocysteinemia (HHC). Most of the Hcy in plasma covalently binds to the cysteine residues of albumin by disulfide bonds. Meanwhile tiopronin (TP), a thiol-containing compound, is used for treatment of cysteinuria to decrease the amount of insoluble cystine in urine, by replacing a cysteine molecule in cystine with TP to form soluble TP-cysteine complexes. The present study investigated the effect of TP on the total (protein-unbound and protein-bound) Hcy concentration and the ratio of protein-unbound Hcy to total Hcy in plasma, and the urinary excretion of Hcy. Methionine was administered orally to rats to induce temporary hyperhomocysteinemia, and then TP was administered and the plasma and urine were collected. The amount of Hcy excreted in urine was higher but the plasma concentration of Hcy was lower in the TP group than in the control group until 3 h after TP administration. In addition the ratio of protein-unbound Hcy in plasma tended to be increased by TP administration. These results demonstrated that TP enhanced the urinary excretion of Hcy, which might cause the decrease of its plasma concentration in rats.

Aortogastric Fistula Caused by a Foreign Body in a Hiatal Hernia.

Foreign body ingestion is more common in children than in adults, and sharp foreign body ingestion is extremely rare. We report a 93-year-old woman who was unaware of foreign body ingestion and who presented with sudden hematemesis and circulatory collapse. Computed tomography showed a hiatus hernia and part of the stomach herniating in the posterior mediastinum. Additionally, a needle-shaped object was seen penetrating the aorta through the herniated gastric wall. Therefore, immediate endovascular repair of the aorta was performed. Subsequent endoscopy identified a bamboo stick. Therefore, emergent laparotomy and gastrotomy were performed to retrieve the stick, followed by repair of the hernia. The postoperative recovery was uneventful. Such cases are associated with high morbidity, mandating long-term follow-up.

Two cases of thoracic aortic aneurysm with right aortic arch: comparison of two operative strategies for hybrid thoracic endovascular repair.

Hybrid TEVAR was performed in 2 patients with right aortic arch accompanied by Kommerell's diverticulum and aortic aneurysm. In patient 1, total debranch + TEVAR was performed with 1-stage median sternotomy. In patient 2, total arch replacement and insertion of a peripheral elephant trunk were performed first, followed by TEVAR. No endoleaks or aortic events were observed in either case during the observation period, and both patients had good postoperative clinical courses. We report our experience with two such cases that were treated with two different methods of hybrid TEVAR, and discuss the merits and demerits of each treatment method.

Missing leaflet: a rare cause of structural deterioration of a bovine pericardial aortic bioprosthesis-report of a case.

We experienced a rare cause of aortic bioprosthesis deterioration in which one of the leaflets disappeared 8.7 years after primary aortic valve replacement (AVR) in a male octogenarian. Successful redo AVR with a 23-mm Magna EASE (Carpentier-Edwards, Irvine, CA) was performed. No embolic complications occurred. We were unable to identify the cause of this devastating complication. When heart failure symptoms develop in patients with bioprostheses, clinicians should therefore consider a diagnosis of acute progression of structural valve deterioration and follow the patient carefully with echocardiography.