Regeneration of Nonhuman Primate Hearts With Human Induced Pluripotent Stem Cell-Derived Cardiac Spheroids.

BACKGROUND: The clinical application of human induced pluripotent stem cell-derived cardiomyocytes (CMs) for cardiac repair commenced with the epicardial delivery of engineered cardiac tissue; however, the feasibility of the direct delivery of human induced pluripotent stem cell-derived CMs into the cardiac muscle layer, which has reportedly induced electrical integration, is unclear because of concerns about poor engraftment of CMs and posttransplant arrhythmias. Thus, in this study, we prepared purified human induced pluripotent stem cell-derived cardiac spheroids (hiPSC-CSs) and investigated whether their direct injection could regenerate infarcted nonhuman primate hearts. METHODS: We performed 2 separate experiments to explore the appropriate number of human induced pluripotent stem cell-derived CMs. In the first experiment, 10 cynomolgus monkeys were subjected to myocardial infarction 2 weeks before transplantation and were designated as recipients of hiPSC-CSs containing 2×107 CMs or the vehicle. The animals were euthanized 12 weeks after transplantation for histological analysis, and cardiac function and arrhythmia were monitored during the observational period. In the second study, we repeated the equivalent transplantation study using more CMs (6×107 CMs). RESULTS: Recipients of hiPSC-CSs containing 2×107 CMs showed limited CM grafts and transient increases in fractional shortening compared with those of the vehicle (fractional shortening at 4 weeks after transplantation [mean ± SD]: 26.2±2.1%; 19.3±1.8%; P<0.05), with a low incidence of posttransplant arrhythmia. Transplantation of increased dose of CMs resulted in significantly greater engraftment and long-term contractile benefits (fractional shortening at 12 weeks after transplantation: 22.5±1.0%; 16.6±1.1%; P<0.01, left ventricular ejection fraction at 12 weeks after transplantation: 49.0±1.4%; 36.3±2.9%; P<0.01). The incidence of posttransplant arrhythmia slightly increased in recipients of hiPSC-CSs containing 6×107 CMs. CONCLUSIONS: We demonstrated that direct injection of hiPSC-CSs restores the contractile functions of injured primate hearts with an acceptable risk of posttransplant arrhythmia. Although the mechanism for the functional benefits is not fully elucidated, these findings provide a strong rationale for conducting clinical trials using the equivalent CM products.

[Successful Removal of Intrapericardial Needle using Needle Guidance System].

A 41-year-old man stuck himself with needle through his pericardium during suicide attempt. Chest radiography revealed several needles in the bilateral lung fields as well. Computed tomography (CT) and echocardiography showed massive pericardial effusion and a needle penetrating the pericardium. The patient was initially treated conservatively, including pericardial drainage, and, seven days later, we removed the needle using syngo Needle Guidance in hybrid operating room. The length of skin incision was only 2 cm, and the postoperative course was uneventful. No previous studies, to the best of our knowledge, have shown the use of syngo Needle Guidance to remove a needle in the pericardial cavity. This surgical procedure is minimally invasive for the patient.

Strategies to improve outcomes for acute type A aortic dissection with cerebral malperfusion.

OBJECTIVES: We aimed to identify predictors of postoperative permanent neurological deficits (PNDs) and evaluate the early management of cerebral perfusion in patients undergoing surgical repair of acute type A aortic dissection with cerebral malperfusion. METHODS: Between October 2009 and September 2018, a total of 197 patients with acute type A aortic dissection underwent aortic replacement. Of these, 42 (21.3%) patients had an imaging cerebral malperfusion (ICM). ICM was assessed preoperatively, which also revealed whether dissected supra-aortic branch vessels were occluded or narrowed by a thrombosed false lumen. After September 2017, early reperfusion and extra-anatomic revascularization were performed in cases with ICM. RESULTS: Hospital mortality rates for cases with ICM were 4.8% (2/42). Before September 2017, PND were observed in 6 patients (54.5%) with preoperative neurological symptoms (n = 11), and 7 patients (33.3%) without neurological symptoms (n = 21) in patients with ICM. Occlusion or severe stenosis of supra-aortic branch vessels (odds ratio, 7.66; P < 0.001), regardless of preoperative clinical neurological symptoms, was a risk factor for PND. After September 2017, 7 of 10 patients with ICM underwent early reperfusion and extra-anatomic revascularization. PND did not occur in any of these 7 patients. CONCLUSIONS: Occlusion or severe stenosis of supra-aortic branch vessels is a predictor of PND risk in patients undergoing surgery for acute type A aortic dissection. Early reperfusion and extra-anatomic revascularization may reduce the risk of neurological complications in patients with ICM, with or without neurological symptoms.

Skeletal muscle quality affects patient outcomes in acute type A aortic dissection.

OBJECTIVES: Although skeletal muscle quantity is linked to surgical outcomes, quality remains unexamined. In this study, we evaluated whether skeletal muscle quality and quantity could predict surgical outcomes in acute type A aortic dissection (ATAAD). METHODS: Skeletal muscle quality and quantity were evaluated using computed tomography (CT) values and the psoas muscle mass index, respectively. From May 2004 to December 2017, 324 ATAAD patients underwent aortic replacement after CT scans and psoas muscle mass index measurements. Patients were grouped into intramuscular fat (IMF; n = 55) and non-IMF (n = 269) deposition groups. RESULTS: The mean ages of the patients were 72.3 ± 9.7 and 66.8 ± 12.1 years (P = 0.002), and hospital mortality rates were 3.6% (2/55) and 7.4% (20/269; P = 0.393) for IMF and non-IMF deposition groups, respectively. IMF deposition was a risk factor for a deterioration in activities of daily living at discharge by multivariable analysis [odds ratio 0.33, 95% confidence interval (CI) 0.16-0.69; P = 0.003]. The mean follow-up was 43.9 ± 36.8 months. The 5-year survival was significantly worse for the IMF deposition group (IMF 73.8% vs non-IMF 88.2%; P = 0.010). The multivariable Cox proportional hazard analysis showed that IMF deposition significantly predicted poor survival (hazard ratio 3.26, 95% CI 1.47-7.24; P = 0.004), unlike psoas muscle mass index and age. CONCLUSIONS: Skeletal muscle quality, defined by IMF deposition, was an independent predictor of overall survival and postoperative activities of daily living dependence risk in patients undergoing surgery for ATAAD. Thus, IMF deposition may be an additional risk factor for estimating late outcomes of ATAAD surgery.

Impact of Frailty on Outcomes in Acute Type A Aortic Dissection.

BACKGROUND: Although frailty is used to predict morbidity and mortality, its effect on the outcomes of acute type A aortic dissection has not been examined. Therefore, the objective of this study was to evaluate the role of frailty in predicting postoperative morbidity and mortality of patients with acute type A aortic dissection. METHODS: A retrospective analysis of a prospectively maintained database was undertaken for all patients (n = 310) undergoing aortic surgery between May 2004 and March 2017. Frailty was evaluated using an index consisting of age more than 70 years, body mass index less than 18.5 kg/m2, serum creatinine greater than 1.2 mg/dL, anemia, history of stroke, hypoalbuminemia, and the psoas muscle area index. One point was given for each criterion met, for a frailty score between 0 and 7. Frailty was defined as a score of 3 or more. RESULTS: Of all patients, 106 (34.2%) were defined as frail. Inhospital mortality rates of frail versus nonfrail patients were not significantly different (10.4% versus 8.3%, respectively; p = 0.54). Incidences of postoperative major morbidities without reexploration for bleeding were also not statistically different. Five-year survival rates were significantly worse for frail patients than for nonfrail patients (57.7% versus 85.1%, respectively; p = 0.0001). A frailty score of 3 or greater was associated with late mortality, and long-term outcomes were clearly stratified by frailty score. CONCLUSIONS: Frailty, as defined using a seven-component frailty index, can serve as an independent predictor of the risk of late mortality for patients undergoing surgery for acute type A aortic dissection. Such frailty markers, all of which are easily assessed preoperatively, may provide valuable information for patient counseling and risk stratification before aortic surgery.

Surgical Repair of Cervical Aortic Arch With Brain Circulation Anomaly Through Clamshell Incision.

We report the successful surgical repair of a cervical aortic arch and diverticulum with a brain circulation anomaly through a clamshell incision. Because of the reliability of selective antegrade cerebral perfusion and superior exposure, we chose an approach through a clamshell incision. We describe the utility of this approach for treating a cervical aortic arch with a diverticulum.

Platelet function during cardiopulmonary bypass using multiple electrode aggregometry: comparison of centrifugal and roller pumps.

Blood trauma may be lower with centrifugal pumps (CPs) than with roller pumps (RPs) during cardiopulmonary bypass (CPB), because, unlike RPs, CPs do not compress the tubing, and shear stress is considered lower in CPs than in RPs. However, relative platelet function remains unclear. Using multiple electrode aggregometry (MEA), we compared platelet function with CP and RP. Ten swine underwent CPB for 3 h, with five weaned off using CP and five using RP. Platelet function was measured using MEA, as were hemoglobin concentration and platelet count, before sternotomy, after heparin infusion, 30 min and 3 h after starting CPB, after protamine infusion, and 60 min after stopping CPB. Platelet activation was initiated with adenosine diphosphate (ADP), arachidonic acid (AA), and thrombin receptor-activating protein 6 (TRAP). Fibrinogen, platelet factor 4 (PF4), and ß-thromboglobin (ß-TG) concentrations were measured before sternotomy and 60 min after stopping CPB. In the CP group and using ADP, aggregation was significantly reduced 30 min (P = 0.019) and 3 h (P = 0.027) after starting CPB, recovering to baseline 60 min after CPB was stopped. In the RP group, aggregation was significantly decreased 30 min (P = 0.007) and 3 h (P = 0.003) after starting CPB and after protamine administration (P = 0.028). With AA, aggregation significantly decreased 30 min after starting CPB in both the CP (P = 0.012) and RP (P = 0.016) groups, slightly increasing 3 h after starting CPB and after protamine infusion, and recovering to baseline 60 min after CPB cessation. With TRAP, aggregation in the CP and RP groups decreased 30 min after starting the pump, although changes were not significant; aggregation gradually recovered after 3 h and returned to baseline 60 min after the pumps were stopped. There were no significant differences at all sampling points of MEA. In both groups, fibrinogen, PF4, and ß-TG concentrations were similar 60 min after pump cessation and before sternotomy. Platelet function, evaluated with MEA, was lowest 30 min after CPB was started but did not decrease over time in either group. As assessed by MEA, platelet function using CP and RP did not differ significantly. Platelet dysfunction was caused mainly by initial contact with foreign materials and may not be dependent on type of pump.