A rare case of delayed complete lead dislodgement after deep septal pacing: A hidden risk of the specific procedure.

Deep septal ventricular pacing is a recently developed physiological pacing modality with good efficacy; however, it has a potential risk of unusual complications. Here, we report a patient with pacing failure and spontaneous, complete lead dislodgement after >2 years of deep septal pacing, possibly caused by systemic bacterial infection and specific lead behavior in the septal myocardium. This case report may implicate a hidden risk of unusual complications in deep septal pacing.

Impact of an improved driveline management for HeartMate II and HeartMate 3 left ventricular assist devices.

BACKGROUND: We evaluated the impact of a standardized driveline care strategy, including a subfascial-tunneling method and dressing protocol, on the incidence of driveline infection (DLI). METHODS: DLI data from all HeartMate II (HMII) and HeartMate 3 (HM3) patients (including exchange devices) were retrospectively collected between 2013 and 2021. The driveline subfascial-tunneling method was altered in three steps (A: right direct; B: left triple, C: right triple), and the shower protocol was changed in two steps (A: with/without cover, B: with cover). Disinfection was individually tailored after changing the shower protocol. Complications associated with morbidity and mortality were evaluated for each modification. RESULTS: During the study period, 80 devices were implanted (HMII, n = 54; HM3, n = 26). The 8-year incidence of DLI was 15% (n = 8) in HMII patients and 0% in HM3 patients (p = 0.039). DLI was not associated with hospital mortality. The modified dressing protocol and tunneling method was associated with a significantly better DLI incidence rate in comparison to the previous one: Protocol-A (n = 17), Protocol-B (n = 63), 35% vs 3% (p = 0.0009), Method-A (n = 13), Method-B (n = 42), Method-C (n = 25), 46% vs 5% vs 0% (p = 0.0001). The rete of freedom form DLI at 1, 2, and 3 years had also significant difference between groups: Protocol-A and Protocol-B, 80%, 54%, 54% vs 96%, 96%, 96%, respectively (p < 0.0001), Method-A, Method-B and Method-C, 76%, 44%, 44%, vs 94%, 94%, 94% vs 100%, 100%, respectively (p < 0.0001). CONCLUSIONS: A standardized triple driveline tunneling strategy and waterproof dressing protocol reduced driveline infection in HM3 patients to 0%.

Therapeutic effect of allogeneic bone marrow-derived mesenchymal stromal cells on aortic aneurysms.

We previously reported the effectiveness of autologous mesenchymal stromal cells (MSCs) for the treatment of aortic aneurysm (AA), mediated mainly by these cells' anti-inflammatory properties. In this study, we investigate whether the therapeutic effects of allogeneic MSCs on AA are the same as those of autologous MSCs. To examine the immune response to allogeneic MSCs, C57BL/6 lymphocytes were co-cultured with BALB/c MSCs for 5 days in vitro. Apolipoprotein E-deficient C57BL/6 mice with AA induced by angiotensin II were randomly divided into three groups defined by the following intravenous injections: (i) 0.2 ml of saline (n = 10, group S) as a control, (ii) 1 × 106 autologous MSCs (isolated from C57BL/6, n = 10, group Au) and (iii) 1 × 106 allogeneic MSCs (isolated from BALB/c, n = 10, group Al). Two weeks after injection, aortic diameters were measured, along with enzymatic activities of MMP-2 and MMP-9 and cytokine concentrations in AAs. Neither allogenic (BALB/c) MSCs nor autologous (C57BL/6) MSCs accelerated the proliferation of lymphocytes obtained from C57BL/6. Compared with group S, groups Au and Al had significantly shorter aortic diameters (group S vs Au vs Al; 2.29 vs 1.40 vs 1.36 mm, respectively, p < 0.01), reduced MMP-2 and MMP-9 activities, downregulated IL-6 and MCP-1 and upregulated expression of IGF-1 and TIMP-2. There were no differences in these results between groups Au and Al. Thus, our study suggests that treatment with allogeneic MSCs improves chronic inflammation and reduced aortic dilatation. These effects were equivalent to those of autologous MSCs in established mouse models of AA.

Is Hybrid Repair for an Entire Shaggy Aorta Feasible?

OBJECTIVE: This paper reviewed clinical experiences to evaluate the feasibility of a surgical strategy for an entire shaggy aorta. METHODS: Fifty-two (52) surgeries (47 men, average age 72±7 years) were performed for an entire shaggy aorta at the current institution from 2002-2017. Open surgery was performed in 30 cases, including total arch replacement in 12, extended aortic arch replacement via L-shaped thoracotomy in 10 and median sternotomy combined with left thoracotomy in two, and thoracoabdominal aortic replacement in six. Hybrid procedures were performed in 22 cases: type I hybrid arch repair in six, type II hybrid arch repair in seven and type III hybrid arch repair in nine. RESULTS: Hospital mortality was significantly higher with a hybrid repair: surgical, one case (3%); hybrid, six cases (27%), (p=0.0125). Stroke occurred at relatively high rates in both groups: surgical, seven cases (23%); hybrid, six cases (27%) (p=0.75). Spinal cord injury was significantly higher in hybrid repair: surgical, one case (3%); hybrid, seven cases (32%), (p=0.004). Open surgery revealed a better long-term survival rate than the hybrid procedure at 5 and 10 years: surgical, 82%, 65.7%; hybrid, 53%, 35.1%, respectively (p=0.0452). The rate of freedom from aortic events was significantly better with open surgery than a hybrid procedure at 5 and 10 years: surgical, 96%, 85%; hybrid, 83%, 41.3%, respectively (p=0.0082). CONCLUSIONS: Surgery for an entire shaggy aorta was frequently associated with embolic complications such as stroke, paraplegia, renal failure, and bowel necrosis. However, open surgical repair may produce better early and late outcomes and freedom from aortic events compared with hybrid repair.

Spinal cord injury following aortic arch replacement.

PURPOSE: Postoperative spinal cord injury is a devastating complication after aortic arch replacement. The purpose of this study was to determine the predictors of this complication. METHODS: A group of 254 consecutive patients undergoing aortic arch replacement via median sternotomy, with (n = 78) or without (n = 176) extended replacement of the upper descending aorta, were included in a risk analysis. The frozen elephant trunk technique was used in 46 patients. The patients' atherothrombotic lesions (extensive intimal thickening of > 4 mm) were identified from computed tomography images. RESULTS: Complete paraplegia (n = 7) and incomplete paraparesis (n = 4) occurred immediately after the operation (permanent spinal cord injury rate, 1.97%; transient spinal cord injury rate, 2.36%). A multivariable logistic regression analysis identified the use of the frozen elephant trunk technique (odds ratio 36.3), previous repair of thoracoabdominal aorta or descending aorta (odds ratio 29.4), proximal atherothrombotic aorta (odds ratio 9.6), chronic obstructive lung disease (odds ratio 7.1) and old age (odds ratio 1.1) as predictors of spinal cord injury (p < 0.0001, area under curve 0.93). CONCLUSIONS: Spinal cord injury occurs with a non-negligible incidence following aortic arch replacement. The full objective assessment of the morphology of the whole aorta and the recognition of the risk factors are mandatory.

The oral administration of clarithromycin prevents the progression and rupture of aortic aneurysm.

OBJECTIVE: The pathogenesis of aortic aneurysm (AA) is associated with chronic inflammation in the aortic wall with increased levels of matrix metalloproteinases (MMPs). Clarithromycin (CAM) has been reported to suppresses MMP activity. In this study, we investigated whether CAM could prevent the formation and rupture of AA. METHODS: Male apolipoprotein E-deficient mice (28-30 weeks of age) were infused with angiotensin II for 28 days. CAM (100 mg/kg/d) or saline (as a control) was administered orally to the mice every day (CAM group, n = 13; control group, n = 13). After the administration period, the aortic diameter, elastin content, macrophage infiltration, MMP levels, and levels of inflammatory cytokines, including nuclear factor κB (NF-κB), were measured. RESULTS: The aortic diameter was significantly suppressed in the CAM group (P < .001). No rupture death was observed in the CAM group in contrast to five deaths (38%) in the control group (P < .01). CAM significantly suppressed the degradation of aortic elastin (56.3% vs 16.5%; P < .001) and decreased the infiltration of inflammatory macrophages (0.05 vs 0.16; P < .01). Compared with the controls, the enzymatic activity of MMP-2 and MMP-9 was significantly reduced in the CAM group (MMP-2, 0.15 vs 0.56 [P < .01]; MMP-9, 0.12 vs 0.60 [P < .01]), and the levels of interleukin 1ß (346.6 vs 1066.0; P < .05), interleukin 6 (128.4 vs 346.2; P < .05), and phosphorylation of NF-κB were also decreased (0.3 vs 2.0; P < .01). CONCLUSIONS: CAM suppressed the progression and rupture of AA through the suppression of inflammatory macrophage infiltration, a reduction in MMP-2 and MMP-9 activity, and the inhibition of elastin degradation associated with the suppression of NF-κB phosphorylation.

Strategy of Cardiovascular Surgery for Patients With Dementia as Evaluated by Mini-Mental State Examination.

BACKGROUND: The strategy for cardiovascular surgery in dementia patients is controversial, so we aimed to investigate whether preoperative dementia and its severity might affect the outcomes of cardiovascular surgery by evaluating with the Mini-Mental State Examination (MMSE). Methods and Results: The study group comprised 490 patients undergoing cardiovascular surgery. Their preoperative cognitive status was evaluated using the MMSE, and analysis was performed to compare the patients with MMSE score <24 (dementia group, n=51) or MMSE score 24-30 (non-dementia group, n=439). Furthermore, the effect of the severity of dementia was analyzed with a cut-off MMSE score of 19/20. Risk factors for surgical outcomes were explored using multivariate logistic regression analysis. Hospital mortality was 11.8% in the dementia group and 2.1% in the non-dementia group (P=0.002). Regarding the postoperative morbidities, the incidence of cerebrovascular disorder (P=0.001), pneumonia (P=0.039), delirium (P=0.004), and infection (P=0.006) was more frequent in dementia group. Among the patients with MMSE <20, hospital mortality was as high as 25%, and the rate of delirium was 58%. Multivariate logistic regression analysis revealed that MMSE score <24 (P=0.003), lower serum albumin (P=0.023) and aortic surgery (P=0.036) were independent risk factors for hospital death. CONCLUSIONS: Preoperative dementia affects the outcomes of cardiovascular surgery with regard to hospital death and delirium. The surgical indication for patients with MMSE <20 might be difficult, but surgery with an appropriate strategy should be considered for patients with MMSE <24.

＜Editors' Choice＞ Effects of exosomes derived from the induced pluripotent stem cells on skin wound healing.

Recently, the effects of stem cell supernatants or exosomes, such as skin wounds, have attracted attention. However, the effects of the induced pluripotent stem (iPS) cell-derived exosomes (iPS-Exos) have not been investigated in detail. Here, we investigated the effects of iPS-Exos on skin wound healing using an animal model. We isolated iPS-Exos from the iPS cell culture media. Control exosomes were isolated from unused iPS cell culture media (M-Exos). We first observed the morphologic characteristics of the isolated exosomes and examined the expression of surface antigens. The effects of these exosomes on the migratory response and proliferation of fibroblasts were analyzed as well. Additionally, using a diabetic ulcer model, the effects of iPS-Exos and M-Exos on skin wound healing were investigated. Transmission electron microscope analysis demonstrated that the size of iPS-Exos (120 ± 25 nm) was significantly larger than that of M-Exos (≤ 100 nm). Flow cytometry analyses showed that iPS-Exos were positive for CD9, CD63, and CD81, whereas they were negative for HLA-ABC and -DR expression. The migratory ability of fibroblasts cocultured with iPS-Exos was shown to be higher than that of the cells cocultured with M-Exos, as demonstrated using scratch assay. Skin wound healing model results showed that the administration of iPS-Exos results in a faster wound closure compared with that observed in the M-Exo group. In conclusion, the results obtained here indicate that iPS-Exos may promote the migration of fibroblasts in vitro and in vivo, suggesting the possibility of using iPS-Exos for the treatment of diabetic ulcer.

Bone marrow-derived mesenchymal stromal cells regress aortic aneurysm via the NF-kB, Smad3 and Akt signaling pathways.

BACKGROUND AIMS: We have confirmed that aortic aneurysm (AA) can be regressed by the administration of bone marrow-derived mesenchymal stromal cells (BM-MSCs). We investigated the kinetics of signaling pathways in AA following treatment with BM-MSCs. METHODS: Angiotensin II-infused apolipoprotein E-deficient mice were treated by intravenous injection of 1 × 106 BM-MSCs in 0.2 mL saline (BM-MSCs group, n = 5) or 0.2 mL saline (saline group, n = 5). Mice were sacrificed 2 weeks after injection and subjected to measurements of the incidence of AA and levels of phosphorylated proteins. Levels of proteins in conditioned media of BM-MSCs were also measured. RESULTS: The incidence of AA in the BM-MSCs group was reduced (BM-MSC 40% versus saline 100%, P <0.05). Levels of pNF-kB and pSTAT1 were reduced (pNF-kB: 0.28 versus 0.45 unit/mL, P <0.05, pSTAT1: 0.16 versus 0.34, P <0.05), whereas levels of pAkt and pSmad3 were elevated (pAkt: 0.13 versus 0.07, P <0.01, pSmad3: 1.07 versus 0.47, P <0.05) in the BM-MSCs group. The levels of pNF-kB, pAkt, and pSmad3 were correlated with aortic diameters. Trophic factors including IGFPB-3, NRF, Activin A and PDGF-AA were secreted from BM-MSCs (IGFBP-3: 35.2 pg/mL, NRF: 3.1 pg/mL, Activin A: 3.1 pg/mL, PDGF-AA: 0.45 pg/mL). CONCLUSIONS: Our findings suggested that the therapeutic mechanism of BM-MSC-mediated AA regression could contribute to regulation of the NF-kB, Smad3 and Akt signaling pathways. In addition, paracrine actions by factors including NRF, IGFBP-3, Activin A and PDGF-AA might have affected these signaling pathways.

Clinical outcomes and quality of life after surgery for dilated ascending aorta at the time of aortic valve replacement; wrapping versus graft replacement.

Wrapping and graft replacement are two optional procedures for the treatment of dilated ascending aorta at the time of aortic valve replacement (AVR). Wrapping is considered less invasive. The aim of this study was to compare the short- and long-term clinical outcomes as well as the long-term quality of life in patients undergoing these two procedures.This study enrolled 40 consecutive patients with dilated ascending aorta who had undergone either wrapping (WAA group, n=20) or replacement (RAA group, n=20) of the ascending aorta at the time of AVR. Short-term outcomes, long-term deaths, and aortic events were evaluated, as was quality of life using the SF-36 Short Form. Long-term maximal proximal aortic diameter was also obtained.There were no early deaths in either group. Pump time was shorter, and transfusion (55% vs. 95%, p=0.035) and postoperative atrial fibrillation (5% vs. 30%, p=0.036) rates were lower, in the WAA than in the RAA group. At a mean follow-up of 4.9 years, the overall 5 year survival rates in the WAA and RAA groups were 78.1% and 87.5%, respectively. There were no significant between group differences in SF-36 scores in any subcategory of this survey. Long-term maximal aortic diameter remained stable in both groups. Both surgical interventions for dilated ascending aorta at the time of AVR yield favorable and comparable results in patients with suitable anatomy. Furthermore, we found no differences in quality of life between these procedures.

[Total Arch Replacement Using Manufactured Frozen Elephant Trunk after Acute Type-A Dissection Repair].

The purpose of this study is to assess the result of total arch replacement(TAR) using manufactured frozen elephant trunk(FET) for chronic aortic dissection after initial repair including the effect of aortic remodeling by the FET. Between 2003 and 2015, we performed 11 TAR using manufactured FET. Initial repairs before were 9 ascending aortic replacements and 2 Bentall operations. The entry of residual dissection was located at arch in 7 and at distal anastomosis site in 4. There was no hospital death. The operative complication included 2 surgical site infection, 1 interstitial pneumonia and 1 paraplegia with almost full recovery. Postoperative computed tomography 2.1 months after operation showed distal end of the FET was located at aortic valve level in 7 and at pulmonary bifurcation level in 4. There was no entry in thoracic aorta. Thrombosis of descending aorta was achieved in 7 patients. Significant midterm aortic remodeling (increased diameter of true lumen and decreased diameter of false lumen) was achieved, although the total diameter of aorta was increased. TAR using manufactured FET after type-A dissection repair promoted entry closure and thrombosis of false lumen. It requires long-term observation to judge the effect for aortic remodeling.

The long-term results and changing patterns of biological valves at the mitral position in contemporary practice in Japan.

Mitral valve surgery has changed with the wide acceptance of mitral valve repair. The aim of this study is to obtain the long-term results of patients who underwent mitral valve replacement (MVR) using a biological prosthesis in contemporary practice in Japan. From January 1990 to December 2013, 76 patients underwent MVR using a biological prosthesis with or without concomitant surgery. Data were obtained by means of a questionnaire and a telephone interview. The mean follow-up period was 4.26 years. The etiologies of the patients included dilated cardiomyopathy (DCM) (n=20 [26.3%]), ischemic mitral regurgitation (n=7 [9.2%]). There is a trend towards decreasing number of rheumatic and degenerative disease and increasing number of DCM and ischemic mitral regurgitation. Three patients (3.9%) died in the perioperative period. The 5- and 10-year overall survival rates were 69.6% and 31.7%, respectively. The 5- and 10-year freedom from valve related death were 95.6% and 80.6 %, respectively. The linearized rates of valve-related complications were as follows: thromboembolism (0.63%/patient/year), bleeding (1.25%/patient/year). One patient underwent reoperation for structural degeneration 13 years after the first operation. The present study shows the long-term results of mitral valve replacement with bioproshtesis in a contemporary case series. The practice pattern is changing. The low rate of valve-related complication justify the current patient selection.

[Aortic Valve Replacement of Quadricuspid Valve with Regurgitation].

Congenital quadricuspid aortic valve is a very rare malformation. In most cases it has been found incidentally at aortic valve surgery or at autopsy. It frequently causes aortic regurgitation, which may become manifest in adulthood and require surgical treatment. We reported 4 cases of aortic regurgitation with quadricuspid aortic valve. In all cases, aortic valve replacement was preformed with prosthetic valve, and their postoperative courses were uneventful. Two were Hurwitz's classification type b, one was type a and the last patient was type c. Although quadricuspid aortic valve is a rare anomaly, its potential for severe valve failure in adulthood should be kept in mind.

The number of cardiovascular surgeries in Japan may decrease after 2020.

The expected future number of cardiovascular operations is estimated based on the predicted Japanese population and the rate of cardiovascular surgery performance calculated from 16845 cases treated by the Nagoya University group of hospitals between 2001 and 2013. The population of <20-year-old individuals has decreased since 1990, while that of 20-64-year-old individuals has also decreased since 2000. The population of 65-79-year-old individuals is expected to peak in 2020, with only the population of ≥80-year-old individuals expected to increase until 2040. The performance rate of cardiovascular surgery per 100,000 population is low in the 20-64-year-old group and increases to reach a peak in the elderly population of 70-74-year-old individuals in valvular heart disease (55.5), ischemic heart disease (54.5) and thoracic aortic aneurysm (31.9) and decreases to about half those values in the ≥80-year-old age group. The number of cardiovascular operations (all types) per 100,000 was 40.6 in 2002, 42.1 in 2006 and 46.6 in 2010. The total number of expected cardiovascular operations is increasing slightly and will reach a peak in 2020 with an estimated 61,506 operations. It then decreases gradually to reach 55966 in 2035, on the premise that the cardiovascular surgery performance rate does not change from the present time. In order to maintain and expand to meet the medical needs of cardiovascular surgery, it is crucial that an effort be made to increase the cardiovascular surgery performance rate, especially in octogenarian patients.

Administration of an antibody against apoptosis inhibitor of macrophage prevents aortic aneurysm progression in mice.

Apoptosis inhibitor of macrophage (AIM) is known to induce apoptosis resistance in macrophages and to exacerbate chronic inflammation, leading to arteriosclerosis. The role of AIM in aortic aneurysm (AA) remains unknown. This study examined the effects of an anti-AIM antibody in preventing AA formation and progression. In apolipoprotein E-deficient mice, AA was induced by subcutaneous angiotensin II infusion. Mice were randomly divided into two groups: (i) AIM group; weekly anti-murine AIM monoclonal antibody injection (n = 10), and (ii) IgG group; anti-murine IgG antibody injection as control (n = 14). The AIM group, compared with the IgG group, exhibited reduced AA enlargement (aortic diameter at 4 weeks: 2.1 vs. 2.7 mm, respectively, p = 0.012); decreased loss of elastic lamellae construction; reduced expression levels of IL-6, TNF-α, and MCP-1; decreased numbers of AIM-positive cells and inflammatory M1 macrophages (AIM: 1.4 vs. 8.0%, respectively, p = 0.004; M1 macrophages: 24.5 vs. 55.7%, respectively, p = 0.017); and higher expression of caspase-3 in the aortic wall (22.8 vs. 10.5%, respectively, p = 0.019). Our results suggest that administration of an anti-AIM antibody mitigated AA progression by alleviating inflammation and promoting M1 macrophage apoptosis.

Thromboelastographic evaluation after cardiac surgery optimizes transfusion requirements in the intensive care unit: a single-center retrospective cohort study using an inverse probability weighting method.

OBJECTIVE: There are no reports from Japan showing the effects of using the thromboelastography algorithm on transfusion requirements after Intensive Care Unit (ICU) admission, and post-implementation knowledge regarding the thromboelastography algorithm under the Japanese healthcare system is insufficient. Therefore, this study aimed to clarify the effect of the TEG6s thromboelastography algorithm on transfusion requirements for patients in the ICU after cardiac surgery. METHODS: We retrospectively compared the requirements for blood transfusion up to 24 h after ICU admission using the thromboelastography algorithm (January 2021 to April 2022) (thromboelastography group; n = 201) and specialist consultation with surgeons and anesthesiologists (January 2018 to December 2020) (non-thromboelastography group; n = 494). RESULTS: There were no significant between-group differences in terms of age, height, weight, body mass index, operative procedure, duration of surgery or cardiopulmonary bypass, body temperature, or urine volume during surgical intervention. Moreover, there was no significant between-group difference in the amount of drainage at 24 h after ICU admission. However, crystalloid and urine volumes were significantly higher in the thromboelastography group than in the non-thromboelastography group. Additionally, fresh-frozen plasma (FFP) transfusion volumes were significantly lower in the thromboelastography group. However, there were no significant between-group differences in red blood cell count or platelet transfusion volume. After variable adjustment, the amount of FFP used from the operating room to 24 h after ICU admission was significantly reduced in the thromboelastography group. CONCLUSIONS: The thromboelastography algorithm optimized transfusion requirements at 24 h after admission to the ICU following cardiac surgery.

Intravenous administration of mesenchymal stem cells prevents angiotensin II-induced aortic aneurysm formation in apolipoprotein E-deficient mouse.

BACKGROUND: Mesenchymal stem cells (MSCs) are known to be capable of suppressing inflammatory responses. We previously reported that intra-abdominal implantation of bone marrow-derived MSCs (BM-MSCs) sheet by laparotomy attenuated angiotensin II (AngII)-induced aortic aneurysm (AA) growth in apolipoprotein E-deficient (apoE-/-) mice through anti-inflammation effects. However, cell delivery by laparotomy is invasive; we here demonstrated the effects of multiple intravenous administrations of BM-MSCs on AngII-induced AA formation. METHODS: BM-MSCs were isolated from femurs and tibiae of male apoE-/- mice. Experimental AA was induced by AngII infusion for 28 days in apoE-/- mice. Mice received weekly intravenous administration of BM-MSCs (n=12) or saline (n=10). After 4 weeks, AA formation incidence, aortic diameter, macrophage accumulation, matrix metalloproteinase (MMP)' activity, elastin content, and cytokines were evaluated. RESULTS: AngII induced AA formation in 100% of the mice in the saline group and 50% in the BM-MSCs treatment group (P < 0.05). A significant decrease of aortic diameter was observed in the BM-MSCs treatment group at ascending and infrarenal levels, which was associated with decreased macrophage infiltration and suppressed activities of MMP-2 and MMP-9 in aortic tissues, as well as a preservation of elastin content of aortic tissues. In addition, interleukin (IL)-1ß, IL-6, and monocyte chemotactic protein-1 significantly decreased while insulin-like growth factor-1 and tissue inhibitor of metalloproteinases-2 increased in the aortic tissues of BM-MSCs treatment group. CONCLUSIONS: Multiple intravenous administrations of BM-MSCs attenuated the development of AngII-induced AA in apoE-/- mice and may become a promising alternative therapeutic strategy for AA progression.

Long-term outcome of complete cardiovascular implantable electronic device removal with cardiopulmonary bypass.

Definitive endovascular techniques have been developed for pacemaker lead extraction; however, a few patients require immediate secondary open heart surgery because of incomplete transvenous lead extraction. This study examined the safety, effectiveness, and long-term outcome of the removal of cardiovascular implantable electronic device (CIED) via median sternotomy under cardiopulmonary bypass. The removal of CIED was performed in 6 patients (mean age 57 ± 16 years, 5 males and 1 female), from September 2000 to April 2011. The reasons for removal included eradication of an infection in 5 patients and elimination of pacemaker component allergy in 1. Positive culture results, including methicillin-sensitive Staphylococcus aureus (MSSA, n = 2), methicillin-resistant S. aureus (MRSA, n = 1), coagulase-negative staphylococci (CNS, n = 1), and methicillin-resistant S. epidermidis (MRSE, n = 1) were observed in all 5 infected patients. Mitral annuloplasty (n = 1), mitral valvuloplasty (n = 1), tricuspid annuloplasty (n = 3). Implantation of myocardial pacing leads (n = 5) were performed concomitantly (n = 4), or secondarily (n = 1). All 6 patients were alive in good condition at 72 ± 55 months following CIED removal. New device infection occurred in 1 patient during long-term follow up. Complete surgical removal of pacing systems via median sternotomy with cardiopulmonary bypass is, therefore, considered to be safe and feasible with acceptable long term results.

A comparative study of two types of sternal pins used for sternal closure: poly-L-lactide sternal pins versus uncalcined hydroxyapatite poly-L-lactide sternal pins.

Bioabsorbable poly-L-lactide (PLLA) sternal pins are applied to reinforce sternal closure during cardiac surgery. However, these pins lack osteoconductivity. A new bioabsorbable sternal pin with osteoconductivity, made of uncalcined hydroxyapatite and poly-L-lactide (u-HA-PLLA) has been developed. This study was conducted to compare the two types of sternal pins in terms of sternal stability and healing after median sternotomy. Between October 2006 and January 2012, 105 patients underwent aortic surgery for aortic aneurysms or dissection via median sternotomy and sternal closure with sternal pins. Among these patients, 75 were followed for 12 months using serial computed tomography (CT). PLLA sternal pins were used in 30 patients (group A) and u-HA-PLLA sternal pins were used in 45 patients (group B). The incidence rates of transverse sternal dehiscence, anteroposterior displacement and complete sternal fusion were evaluated using CT. The cross-sectional cortical bone density area (CBDA) of the sternum around the sternal pins was examined to evaluate the osteoconductivity of the sternal pins. There were no significant differences between groups A and B in the sternal dehiscence rate (6.7 vs 4.4 %), sternal displacement rate (6.7 vs 2.2 %) or 12-month sternal fusion rate (63.3 vs 73.3 %). The CBDA around the sternal pins significantly increased between discharge and 12 months after surgery in group B (P < 0.001) but not in group A. These results show that u-HA-PLLA sternal pins exhibit certain osteoconductivity; however, both PLLA and u-HA-PLLA sternal pins provide comparable clinical outcomes regarding sternal stability and healing.

A review of current status of cell-based therapies for aortic aneurysms.

An aortic aneurysm (AA) is defined as focal aortic dilation that occurs mainly with older age and with chronic inflammation associated with atherosclerosis. The aneurysmal wall is a complex inflammatory environment characterized by endothelial dysfunction, macrophage activation, vascular smooth muscle cell (VSMC) apoptosis, and the production of proinflammatory molecules and matrix metalloproteases (MMPs) secreted by infiltrated inflammatory cells such as macrophages, T and B cells, dendritic cells, neutrophils, mast cells, and natural killer cells. To date, a considerable number of studies have been conducted on stem cell research, and growing evidence indicates that inflammation and tissue repair can be controlled through the functions of stem/progenitor cells. This review summarizes current cell-based therapies for AA, involving mesenchymal stem cells, VSMCs, multilineage-differentiating stress-enduring cells, and anti-inflammatory M2 macrophages. These cells produce beneficial outcomes in AA treatment by modulating the inflammatory environment, including decreasing the activity of proinflammatory molecules and MMPs, increasing anti-inflammatory molecules, modulating VSMC phenotypes, and preserving elastin. This article also describes detailed studies on pathophysiological mechanisms and the current progress of clinical trials.