A novel double snare technique to retrieve embolized septal and left atrial appendage occluders.

BACKGROUND: Device embolization is the most frequent procedural complication during transcatheter closure of congenital cardiac defects. Retrieval of an embolized device may often be complicated by failure to introduce the right atrial (RA) disk hub into the sheath or difficulty in securely grasping the hub pin of RA disk. We aimed to evaluate the efficiency and success rate of device retrieval using a novel double snare technique. METHODS: We reviewed retrieval procedures of embolized atrial septal defect (ASD) or left atrial appendage (LAA) occluder using double snare technique reported from five tertiary referral centers in Korea, Japan, and Uzbekistan. A total of 16 retrieval procedures in 15 patients were reported, including 14 patients who were planned for ASD device closure while 1 patient was planned for LA appendage occlusion. RESULTS: Retrieved devices included 15 ASD occluders from six different manufacturers and one Amplantzer cardiac plug. Success rate of retrieval procedure was 100% using the double snare technique. There were no complications related to device retrieval. Most (15/16, 93.8%) of these devices could be retrieved through their original delivery sheaths. In six patients for whom retrieval was unsuccessful with conventional single snare technique and switched to double snare technique, the retrieval time was shortened significantly (P = 0.004*) by using the double snare technique. CONCLUSIONS: The double snare technique enables effective retrieval of various embolized devices. It abolishes the need of changing the sheath to a larger one in most patients.

Modification to the injection needle to a screw needle improves effective cell delivery in acute myocardial infarction.

Evaluation of therapeutic effects of transplanted cells in ischemic heart failure models are important issues. However, traditional injection needles that are widely used in clinical practice tend to reduce the amount of functional cells relative to the injected amount. We now describe a cell transplantation technique using a screw needle. After inducing acute myocardial infarction in a rat model, human embryonic stem cell-derived endothelial cells were injected into the infarcted regions with a screw or straight-curved needle. When an equal volume of cells was transplanted, the screw group suffered minimal cell loss, showed improvement in LV wall thickness (74.5 ± 6.2 vs. 64.4 ± 7.8 %), epicardium scar length (19.3 ± 2.8 vs. 24.6 ± 6.4 %), and area of engraft. Thus, even a simple change in the structure of an instrument can have a large impact on transplantation efficiency.

Overexpression of phosphoinositide-3-kinase class II alpha enhances mesenchymal stem cell survival in infarcted myocardium.

The efficacy of mesenchymal stem cell (MSC) therapy for myocardial regeneration is limited by the poor survival of stem cells after transplantation into the infarcted heart. To improve the cell survival of MSCs in the infarcted heart, MSCs were genetically engineered to overexpress phosphoinositide-3-kinase class II alpha (PI3K-C2α). PI3K-C2α overexpression increased PI3K expression and the cell viability of MSCs. Furthermore, levels of survival-related phosphorylation were elevated in PI3K-C2α-MSCs. But, the level of apoptotic proteins downregulated and the number of PI-positive cells decreased in PI3K-C2α-MSCs compared to hypoxic MSCs. Nine rats per group had 1×10(6) cells (20 µl PBS) transplanted after myocardial infarction. One week after transplantation, infarct size and area of fibrosis were reduced in the PI3K-C2α-MSC-transplanted group. The number of TUNEL positive cells declined, while the mean microvessel count per field was higher in the PI3K-C2α-MSC group than the MSC-injected group. Heart function was improved in the PI3K-C2α-MSCs group as assessed using a Millar catheter at 3weeks after transplantation. These findings suggest that overexpression of PI3K-C2α in MSCs can assist cell survival and enhance myocardial regeneration.

Which Neural Tract Plays a Major Role in Memory Impairment After Multiple Cerebral Infarcts? A Case Report.

Injury to the thalamocortical tract (one in the Papez circuit) that leads to memory impairment following brain injury is very rare. In this study, we present a case of partial injury to the thalamocortical tract that causes memory impairment after concurrent thalamic and hippocampal infarct. A 20-year-old male complained of memory impairment 1 month after partial injury to the thalamocortical tract. Using a probabilistic diffusing tensor tractography, it was found that the right thalamocortical tract was thinner than the left thalamocortical tract. However, all other neural tracts including the fornix, cingulum, and mammillothalamic tract were intact on both hemispheres. Therefore, the memory impairment in this patient was considered as being due to thalamic infarct based on the observation that the fornix from hippocampal infarct was intact. This case suggests that the assessment of lesions in the neural tracts of the Papez circuit might be useful for understanding the mechanism of memory impairment following cerebral infarction.

Mechanism of cognitive impairment in chronic patients with putaminal hemorrhage: A diffusion tensor tractography.

It is not clear whether the fornix and cingulum are involved in cognition after putaminal hemorrhage (PH). We investigated structural changes and differences of the neural tracts, and the relationship between the integrity of the neural tracts and cognition not only at the affected but also at the unaffected side.Sixteen patients with left chronic putaminal hemorrhage and 20 healthy volunteers were enrolled. Using diffusion tensor tractography (DTT), we compared fiber number (FN), fractional anisotropy (FA), and apparent diffusion coefficient (ADC) of the neural tracts between patient and control groups. The relationship between the neural tract parameters and neuropsychological results was also analyzed.The left fornix FN was significantly lower than the right fornix FN in the patient group. Except for the cingulum FA, the neural tracts parameters for both the affected and unaffected hemispheres differed significantly between the groups. The fornix FA and ADC at the affected side were significantly correlated with intelligence quotient (IQ), mini-mental status examination (MMSE), and short-term memory. Interestingly, the fornix ADC at the unaffected side was significantly correlated with MMSE. However, none of the cingulum parameters was correlated with neuropsychological results.The fornix integrity is critical for cognitive impairment after putaminal hemorrhage.

Serum levels of advanced glycation end products are associated with in-stent restenosis in diabetic patients.

The formation of advanced glycation end products (AGEs), in various tissues has been known to enhance immunoinflammatory reactions and local oxidant stresses in long standing diabetes. Recently, AGEs have been reported to play a role in neointimal formation in animal models of arterial injury. We attempted to determine whether the serum levels of AGEs are associated with coronary restenosis in diabetic patients. Blood samples were collected from diabetic patients with coronary artery disease undergoing stent implantation and the serum levels of AGEs were analyzed by the fluorescent intensity method. The development of in-stent restenosis (ISR) was evaluated by a 6-month follow-up coronary angiography. A total of 263 target lesions were evaluated, in 203 patients. The ISR rate in the high-AGE (>170 U/ml) group (40.1%) was significantly higher than in the low-AGE group (

Upregulation of extracellular matrix metalloproteinase inducer (EMMPRIN) and gelatinases in human atherosclerosis infected with Chlamydia pneumoniae: the potential role of Chlamydia pneumoniae infection in the progression of atherosclerosis.

Chlamydia pneumoniae infection implicated as an important etiologic factor of atherosclerosis, especially in coronary artery disease (CAD), was found in vitro to be associated with the induction of matrix metalloproteinases (MMPs). An extracellular matrix metalloproteinase inducer (EMMPRIN)/ membrane-type 1 matrix metalloproteinase (MT1-MMP) system which induces and activates MMPs, is suggested to be functional and were upregulated in the failing myocardium. However, the upstream regulation of MMPs by C. pneumoniae within atheroma itself remains unclear. We evaluated the seroepidemiologic study of C. pneumoniae infection in CAD patients (n= 391) and controls (n=97) and performed histopathological and in vitro analysis in atherosclerotic vascular tissues obtained from patients with seropositive to C. pneumoniae (n=20), by using immunochemistry for C. pneumoniae, EMMPRIN/MT1-MMP, MMP-2, and MMP-9. The seropositive rates of both anti-C. pneumoniae IgG and IgA were 56.7% in CAD group and 43.3% in control group (P=0.033). Seropositive rate was increased in subgroups of CAD patients without conventional coronary risk factors compared to those with conventional risk factors. Immunoreactivities of EMMPRIN, MT1-MMP, MMP-2, and MMP-9 were increased in the atheromatous plaque itself, predominantly in immunoreactive macrophages/mononuclear cells to C. pneumoniae. Furthermore, Western blot analysis showed that EMMPRIN and MMP-2 were detected more prominently in atherosclerotic tissues infected with C. pneumoniae compared to control tissues. Zymographic analysis revealed that activities of MMP-2 and MMP-9 were more increased in atherosclerotic tissues infected with C. pneumoniae compared to control tissues. The present study demonstrated upstream regulation of MMPs can be induced by C. pneumoniae within atheromatous plaque itself. These findings help to understand the potential role of C. pneumoniae in the progression of atherosclerosis.

The use of aggregates of purified cardiomyocytes derived from human ESCs for functional engraftment after myocardial infarction.

Embryonic stem cells (ESCs) have the capacity to undergo directed differentiation into contracting cardiomyocytes. Therefore, functional cardiomyocytes derived from human embryonic stem cells (hESC-CMs) are potential candidates for cellular cardiomyoplasty to regenerate the myocardium after infarction. However, the directed differentiation of hESCs induces not only contracting cardiomyocytes but also other cell types. Thus, a risk of teratoma formation and oncologic transformation exists following the transplantation of hESC-CMs containing other cell lineages. In addition, the transplantation of hESC-CMs into the infarcted myocardium limits therapeutic efficacy due to low viability and poor engraftment. In this study, we established an efficient preparation method to obtain pure contracting cardiomyocytes from hESCs. We also developed a delivery system to achieve enhanced viability and a functional connection with the host myocardium after transplantation in a myocardial infarction model. A serum-free medium was used to obtain pure contracting cardiomyocytes from other cell lineages after the cardiac differentiation of hESCs. Aggregates of purified hESC-CMs were formed, and then the expression of cardiomyocyte-specific markers and the viability of the aggregated CMs were examined in hypoxic conditions. In addition, we determined whether the viability of the hESC-CMs and their ability to engraft with the host myocardium could be enhanced by transplanting them as aggregates in a myocardial infarction model. The therapeutic efficacy of the cardiomyocytes was examined by immunohistochemical analyses as well as physiological analyses of left-ventricular function. We found that the transplantation of contracting hESC-CM aggregates improved their survival and function in infarcted rat hearts in comparison to the transplantation of dissociated cells. Our method using hESC-CMs can be considered an effective strategy for clinical applications without critical barriers.

Aortic dissection and rupture in an 11-year-old child: A case report.

We present the case of an 11-year-old boy who developed sudden severe chest pain. When he was referred to the emergency department with this chest pain and palpitation, he could not even stand up. The sudden onset of chest pain was first complained about while he was swimming at school about 30 min previously. His arterial blood pressure was 150/90 mm Hg, heart rate was 120/min, and the chest pain was combined with shortness of breath and diaphoresis. During the evaluation in the emergency room, he complained of much severer chest pain and newly developed abdominal pain. We suspected aortic dissection and took computed tomography (CT) images of his chest and abdomen. The diagnosis of aortic dissection type B was established with the help of CT imaging. The patient went to surgery immediately with blood pressure control. He was lost before the operation because of aortic rupture. We report one rare case of aortic dissection type B with rupture in an eleven-year-old child in Korea.

Aortic dissection and rupture in a child.

After developing sudden severe chest pain, an 11-year-old boy presented to the emergency room with chest pain and palpitations and was unable to stand up. The sudden onset of chest pain was first reported while swimming at school about 30 minutes prior to presentation. Arterial blood pressure (BP) was 150/90 mmHg, heart rate was 120/minute, and the chest pain was combined with shortness of breath and diaphoresis. During the evaluation in the emergency room, the chest pain worsened and abdominal pain developed. An aortic dissection was suspected and a chest and abdomen CT was obtained. The diagnosis of aortic dissection type B was established by CT imaging. The patient went to surgery immediately with BP control. He died prior to surgery due to aortic rupture. Here we present this rare case of aortic dissection type B with rupture, reported in an 11-year-old Korean child.

Is stem cell-based therapy going on or out for cardiac disease?

Acute myocardial infarction and subsequent heart failure are leading causes of death worldwide. Stem cell-based therapies have improved cardiac function in recent clinical trials, but cardiomyocyte regeneration has not been demonstrated in human hearts. Angiogenesis and restoration of cardiac perfusion have been successfully performed using bone marrow derived stem cells and other adult stem cells. Resident cardiac stem cells are known to differentiate into multiple heart cell types, including cardiomyocytes. Furthermore, induced pluripotent stem cells are a focus of research due to the great potential for customized stem cell therapy.

Isolated pulmonary arterial hypertension-janus' faces of hyperthyroidism.

We describe a 54-year-old woman with isolated pulmonary arterial hypertension accompanied by hyperthyroidism due to Graves' disease. Her pulmonary artery hypertension resolved spontaneously after restoration of euthyroidism. This case suggests that hyperthyroidism should be considered a reversible cause of pulmonary arterial hypertension.

Clopidogrel pretreatment before primary percutaneous coronary stenting in patients with acute ST-segment elevation myocardial infarction: comparison of high loading dose (600 mg) versus low loading dose (300 mg).

BACKGROUND: Aggressive platelet inhibition is crucial to reduce myocardial injury and early cardiac events after coronary intervention. As compared with the conventional 300-mg dose, pretreatment with a 600-mg loading dose of clopidogrel significantly reduced periprocedural myocardial infarction (MI) in patients undergoing percutaneous coronary intervention (PCI). We investigated that the advantage of the 600-mg dose in inhibiting platelet aggregation more rapidly than the 300-mg dose may actually have special value for acute ST-segment elevation MI patients. METHODS: A total of 171 patients with ST-segment elevation MI underwent primary PCI. A 600-mg (n=73) or 300-mg (n=98) loading regimen of clopidogrel was given before the procedure. We did a follow-up of all patients clinically for 30 days after coronary intervention. The primary endpoint was the 30-day occurrence of death, MI, urgent revascularization, or stroke. RESULTS: The primary endpoint occurred in 1.4% (1 of 73) of patients in the high dose versus 11.2% (11 of 98) of those in the conventional loading dose group (P=0.013). Death, recurrent MI, urgent revascularization, and stroke were lower in patients treated with the high dose of clopidogrel compared with conventional dose. Safety endpoints were similar in the two groups. CONCLUSION: Pretreatment with a 600-mg loading dose of clopidogrel before the procedure is safe and, as compared with the conventional 300-mg dose, significantly reduces recurrent MI and urgent revascularization in patients with primary PCI.

Successful endovascular treatment of iatrogenic coronary artery dissection extending into the entire ascending aorta.

Iatrogenic acute dissection of the ascending aorta during percutaneous coronary intervention occurs rarely. Localized aortic dissections may be treated by sealing the entry with a coronary stent. However, extensive dissections may require a surgical intervention. A case of iatrogenic coronary dissection with extensive propagation into the ascending aorta during angioplasty of the right coronary artery is presented. The aortic dissection was successfully treated by stenting at the right coronary artery ostium. Follow-up computed tomography and coronary angiography showed complete resolution of aortic dissection.