First Report of Electromagnetic Interference Between Percutaneous Ventricular Assist Device and Implantable Cardioverter-Defibrillator.

Electromagnetic interference (EMI) between implantable left ventricular assist devices and cardiac implantable electronic devices has been observed. We demonstrated the first case of EMI between a percutaneous ventricular assist device and an implantable cardioverter-defibrillator, validated by an extra vivo simulation test. EMI might depend on the distance between devices. (Level of Difficulty: Advanced.).

Lysophosphatidylserine induces necrosis in pressure overloaded male mouse hearts via G protein coupled receptor 34.

Heart failure is a leading cause of mortality in developed countries. Cell death is a key player in the development of heart failure. Calcium-independent phospholipase A2ß (iPLA2ß) produces lipid mediators by catalyzing lipids and induces nuclear shrinkage in caspase-independent cell death. Here, we show that lysophosphatidylserine generated by iPLA2ß induces necrotic cardiomyocyte death, as well as contractile dysfunction mediated through its receptor, G protein-coupled receptor 34 (GPR34). Cardiomyocyte-specific iPLA2ß-deficient male mice were subjected to pressure overload. While control mice showed left ventricular systolic dysfunction with necrotic cardiomyocyte death, iPLA2ß-deficient mice preserved cardiac function. Lipidomic analysis revealed a reduction of 18:0 lysophosphatidylserine in iPLA2ß-deficient hearts. Knockdown of Gpr34 attenuated 18:0 lysophosphatidylserine-induced necrosis in neonatal male rat cardiomyocytes, while the ablation of Gpr34 in male mice reduced the development of pressure overload-induced cardiac remodeling. Thus, the iPLA2ß-lysophosphatidylserine-GPR34-necrosis signaling axis plays a detrimental role in the heart in response to pressure overload.

Successful Bridging to Allogeneic Hematopoietic Stem Cell Transplantation by Azacitidine and Venetoclax in a Case of Acute Myeloid Leukemia With t(3;3)(q21.3;q26.2) Developed Early After Orthotopic Heart Transplantation.

A 48-year-old male patient developed acute myeloid leukemia (AML) with t(3;3)(q21.3;q26.2) chromosomal mutation 8 months after orthotopic heart transplantation from a human leukocyte antigen-unmatched brain-dead donor for cardiac sarcoidosis. He had sequelae of stroke and chronic renal failure at the time of AML diagnosis. He received 3 cycles of azacitidine and venetoclax induction therapy and achieved complete hematological remission with incomplete count recovery without causing severe complications, including infection. He sequentially underwent allogeneic peripheral blood stem cell transplantation from a HLA-8/8 matched, ABO-blood matched, unrelated female donor and successfully achieved donor cell engraftment. His transplanted heart was viable, and the coronary vessels were not damaged even after allogeneic peripheral blood stem cell transplantation. Although AML relapsed afterward, azacytidine/venetoclax was a tolerable bridging therapy even for early-onset AML after heart transplantation.

End-stage Hypertrophic Cardiomyopathy with Advanced Heart Failure in Patients Carrying MYH7 R453 Variants: A Case Series.

The MYH7 R453 variant has been identified in inherited hypertrophic cardiomyopathy (HCM) and is associated with sudden death and a poor prognosis. The detailed clinical course of HCM with the MYH7 R453 variant, from a preserved to a reduced left ventricular ejection fraction, has not been reported. We identified the MYH7 R453C and R453H variants in three patients who progressively developed advanced heart failure requiring circulatory support and summarized the clinical course and echocardiographic parameters of these patients over the years. Because of the rapid disease progression, we consider genetic screening for patients with HCM imperative for future prognosis stratification.

Rubicon-regulated beta-1 adrenergic receptor recycling protects the heart from pressure overload.

Heart failure has high morbidity and mortality in the developed countries. Autophagy is important for the quality control of proteins and organelles in the heart. Rubicon (Run domain Beclin-1-interacting and cysteine-rich domain-containing protein) has been identified as a potent negative regulator of autophagy and endolysosomal trafficking. The aim of this study was to investigate the in vivo role of Rubicon-mediated autophagy and endosomal trafficking in the heart. We generated cardiomyocyte-specific Rubicon-deficient mice and subjected the mice to pressure overload by means of transverse aortic constriction. Rubicon-deficient mice showed heart failure with left ventricular dilatation, systolic dysfunction and lung congestion one week after pressure overload. While autophagic activity was unchanged, the protein amount of beta-1 adrenergic receptor was decreased in the pressure-overloaded Rubicon-deficient hearts. The increases in heart rate and systolic function by beta-1 adrenergic stimulation were significantly attenuated in pressure-overloaded Rubicon-deficient hearts. In isolated rat neonatal cardiomyocytes, the downregulation of the receptor by beta-1 adrenergic agonist was accelerated by knockdown of Rubicon through the inhibition of recycling of the receptor. Taken together, Rubicon protects the heart from pressure overload. Rubicon maintains the intracellular recycling of beta-1 adrenergic receptor, which might contribute to its cardioprotective effect.

Administration of a TLR9 Inhibitor Attenuates the Development and Progression of Heart Failure in Mice.

Mitochondrial deoxyribonucleic acid, containing the unmethylated cytidine-phosphate-guanosine motif, stimulates Toll-like receptor 9 to induce inflammation and heart failure. A small chemical, E6446 [(6-[3-(pyrrolidin-1-yl)propoxy)-2-(4-(3-(pyrrolidin-1-yl)propoxy)phenyl]benzo[d]oxazole)], is a specific Toll-like receptor 9 inhibitor in cardiomyocytes. In this study, we showed that E6446 exerts beneficial effects for the prevention and treatment of pressure overload-induced heart failure in mice. When administered before the operation and chronically thereafter, E6446 prevented the development of left ventricular dilatation as well as cardiac dysfunction, fibrosis, and inflammation. Furthermore, when administered after the manifestation of cardiac dysfunction, E6446 slowed progression of cardiac remodeling. Thus, the inhibitor may be a novel therapeutic agent for treating patients with heart failure.

Bcl-2-like protein 13 is a mammalian Atg32 homologue that mediates mitophagy and mitochondrial fragmentation.

Damaged mitochondria are removed by mitophagy. Although Atg32 is essential for mitophagy in yeast, no Atg32 homologue has been identified in mammalian cells. Here, we show that Bcl-2-like protein 13 (Bcl2-L-13) induces mitochondrial fragmentation and mitophagy in mammalian cells. First, we hypothesized that unidentified mammalian mitophagy receptors would share molecular features of Atg32. By screening the public protein database for Atg32 homologues, we identify Bcl2-L-13. Bcl2-L-13 binds to LC3 through the WXXI motif and induces mitochondrial fragmentation and mitophagy in HEK293 cells. In Bcl2-L-13, the BH domains are important for the fragmentation, while the WXXI motif facilitates mitophagy. Bcl2-L-13 induces mitochondrial fragmentation in the absence of Drp1, while it induces mitophagy in Parkin-deficient cells. Knockdown of Bcl2-L-13 attenuates mitochondrial damage-induced fragmentation and mitophagy. Bcl2-L-13 induces mitophagy in Atg32-deficient yeast cells. Induction and/or phosphorylation of Bcl2-L-13 may regulate its activity. Our findings offer insights into mitochondrial quality control in mammalian cells.

Atherosclerotic change at one year after implantation of Endeavor zotarolimus-eluting stent vs. everolimus-eluting stent.

BACKGROUND: Atherosclerosis progression is thought to be one of the mechanisms of late stent failure. Atherosclerosis progression is detected as yellow plaque formation on angioscopy. Cypher sirolimus-eluting stent has been reported to accelerate atherosclerosis progression, but the influence of Endeavor zotarolimus-eluting stent (Endeavor-ZES) or Xience everolimus-eluting stent (Xience-EES) on atherosclerosis has not been clarified. Therefore, we examined the serial changes in extent of atherosclerosis after the implantation of Endeavor-ZES or Xience-EES. METHODS AND RESULTS: Consecutive patients who received implantation of Endeavor-ZES (n=25) or Xience-EES (n=30) at de novo lesion of native coronary artery and who had successful angioscopy immediately after stent implantation (baseline) and at 1-year follow-up were included in the study. Change in the maximum yellow color grade (grade 0-3) of the stented segment from baseline to follow-up was examined and was compared between Endeavor-ZES and Xience-EES. The maximum yellow color grade decreased significantly from baseline to follow-up in Endeavor-ZES (1.6±1.1 vs. 0.4±0.8, P<0.001), but it did not change in Xience-EES (1.7±1.0 vs. 1.4±0.7, P=0.23). Although the maximum yellow color grade was not different between Endeavor-ZES and Xience-EES at baseline (P=0.72), it was significantly lower in Endeavor-ZES than in Xience-EES at follow-up (P<0.001). CONCLUSIONS: Atherosclerosis evaluated by yellow color of the plaque was significantly reduced at 1 year after Endeavor-ZES implantation, but was not changed after Xience-EES implantation.

Positive peritoneal washing cytology is a potential risk factor for the recurrence of curatively resected colorectal cancer.

PURPOSES: Whether free peritoneal cancer cells should be considered peritoneal dissemination in colorectal cancer patients remains controversial. The aim of this study was to investigate the clinical significance of positive peritoneal washing cytology (PWC) in patients with colorectal cancer. METHODS: We retrospectively analyzed the records of 771 sequential patients diagnosed with stage 0-III colorectal cancer who underwent R0 resection and had no distant metastases or peritoneal dissemination. RESULTS: PWC was performed on all 771 patients. Sixty-eight patients experienced metastasis recurrence, 10 of whom experienced peritoneal recurrence. Of the 10 patients with peritoneal recurrence, 6 had positive PWC. Out of the 771 patients, 21 had positive PWC. Of these 21 patients, 6 had peritoneal recurrence, while 4 had distant metastasis and no peritoneal recurrence during the observation period. The 5-year disease-free survival was 89.0 % in the patients with negative PWC vs. 46.8 % in the patients with positive PWC (p < 0.0001, log-rank test). A Cox proportional hazards model revealed that positive PWC was the strongest independent risk factor for cancer-specific recurrence. CONCLUSIONS: Our study highlights PWC as a useful prognostic tool in patients undergoing curative surgery for colorectal cancer, since positive PWC was shown to be a potential risk factor for recurrence.

Frequency and location of yellow and disrupted coronary plaques in patients as detected by angioscopy.

BACKGROUND: Clarification of frequency and distribution of yellow plaques and disrupted plaques will increase understanding of acute coronary syndrome (ACS) onset. METHODS AND RESULTS: Consecutive patients with ACS (n=75) or without ACS (n=90) who received coronary angioscopic examination were studied. Distance from ostium to yellow plaques, diameter stenosis and vessel wall irregularity at the site of yellow plaques, their yellow color grade (grade 13) and if they had thrombus were analyzed. Yellow plaques with thrombus were regarded as disrupted. Average number of yellow plaques, grade-3 yellow plaques and disrupted yellow plaques per vessel was 4.0, 0.87 and 1.0, respectively. The number of grade-3 yellow plaques and disrupted yellow plaques per vessel were larger in ACS than in non-ACS patients. Yellow plaques were distributed diffusely in the right coronary artery but more in mid-segments in the left anterior descending coronary artery and left circumflex coronary artery. Diameter stenosis in the non-culprit segments was severer at disrupted than at non-disrupted yellow plaques. Vessel wall irregularity was detected more frequently at disrupted than at non-disrupted yellow plaques. CONCLUSIONS: Approximately 4 yellow plaques, 1 grade-3 yellow plaque and 1 disrupted yellow plaque were detected per vessel. About 25% of detected yellow plaques were disrupted. More grade-3 yellow plaques and disrupted yellow plaques were detected in ACS than in non-ACS patients. These findings strengthen the association between yellow plaques detected by angioscopy and ACS events.

Acute coronary syndrome: insight from angioscopy.

Although the concept of vulnerable plaque has become common, it is still impossible to predict effectively the onset of acute coronary syndrome (ACS). Thin-cap fibroatheroma (TCFA) is regarded as vulnerable from pathological studies and various diagnostic tools have tried to detect TCFA clinically but failed to predict ACS. Because there are so many silent plaque ruptures detected, it is supposed that many vulnerable plaques might have ruptured but not caused ACS. Some factor(s) other than the rupture of vulnerable plaque is required for the onset of ACS. "Vulnerable blood" may be one of them. The thrombogenic potential of blood (ie, vulnerable blood) may play an important and determinant role in the onset of ACS, the process of which will be discussed from the angioscopic point of view.