Reinforcement of pimobendan with guideline-directed medical therapy may reduce the rehospitalization rates in patients with heart failure: retrospective cohort study

BACKGROUND

Pimobendan reportedly improves the subjective symptoms of heart failure. However, evidence of improved prognosis is lacking. This study aimed to determine whether reinforcing guideline-directed medical therapy (GDMT) improved rehospitalization rates for worsening heart failure in patients administered pimobendan.

METHODS

A total of 175 patients with heart failure who were urgently admitted to our hospital for worsening heart failure and who received pimobendan between January 2015 and February 2022 were included. Of the 175 patients, 44 were excluded because of in-hospital death at the time of pimobendan induction. The remaining 131 patients were divided into two groups, the reduced ejection fraction (rEF) (n = 93) and non-rEF (n = 38) groups, and further divided into the GDMT-reinforced and non-reinforced groups.

RESULTS

In patients with rEF, the rate of rehospitalization for heart failure was significantly lower in the GDMT-reinforced group than in the non-reinforced group (log-rank test, P = .04). However, the same trend was not observed in the non-rEF group.

CONCLUSIONS

Reinforcing GDMT may reduce the heart failure rehospitalization rate in patients with pimobendan administration and rEF. However, multicenter collaborative research is needed.

TRIAL REGISTRATION

IRB Approval by the Nippon Medical School Hospital Ethics Committee B-2021-433 (April 10, 2023).

Fractional excretion of urea nitrogen can identify true worsening renal function in patients with heart failure

AIMS

Fractional excretion of urea nitrogen (FEUN), used to differentiate the cause of acute kidney injury, has emerged as a useful fluid index in patients with heart failure (HF). We hypothesized that FEUN could be useful in identifying worsening renal function (WRF) associated with poor outcomes in patients with acute HF (AHF).

METHODS AND RESULTS

Overall, 1103 patients with AHF (median age, 78 years; male proportion, 60%) were categorized into six groups according to the presence of WRF and FEUN values (low, ≤32.1%; medium, >32.1% and ≤38.0%; and high, >38.0%) at discharge. WRF was defined as an increase of ≥0.3 mg/dL in the serum creatinine level from admission to discharge. FEUN was calculated by the following formula: (urinary urea × serum creatinine) × 100/(serum urea × urinary creatinine). The cut-off values for low, medium, and high FEUN were based on a previous study. The primary outcome of this study was HF readmission after hospital discharge. During the 1 year follow-up, 170 HF readmissions occurred. Kaplan-Meier analysis revealed significantly higher HF readmission rates in patients with WRF than in those without WRF (log-rank test, P < 0.001). Additionally, among patients with WRF, HF readmission rates were lowest in those with medium FEUN values, followed by those with low FEUN values and those with high FEUN values. On multivariable analysis, the presence of WRF with low or high FEUN values was independently associated with increased HF readmission, as compared with the absence of WRF with medium FEUN values. Notably, no association was noted between WRF with medium FEUN values and HF readmission.

CONCLUSIONS

The prognostic impact of WRF was significantly mediated by the FEUN values and was associated with worse outcomes only when the FEUN values were either low or high. Our study suggests that FEUN can identify prognostically relevant WRF in patients with AHF.

Effectiveness of Repetitive Hyperbaric Oxygen Therapy for Chronic Limb-Threatening Ischemia

BACKGROUND

Lower extremity artery disease is strongly associated with morbidity and is typically addressed through revascularization interventions. We assessed the clinical outcomes of patients with chronic limb-threatening ischemia (CLTI) without revascularization who did and did not undergo repetitive hyperbaric oxygen therapy (HBOT).

METHODS

Between April 2002 and March 2017, the records of 58 patients with CLTI (Rutherford classification 4 in 19% and 5 in 81%) were evaluated retrospectively. HBOT was performed at 2.8 atm of oxygen (HBOT group). The control group included those who could not continue HBOT and historical controls. Patients in poor general health or with an indication for revascularization therapy were excluded. We examined major adverse events (MAEs) and limb salvage rates. Independent predictors and risk stratification were analyzed using a multivariate regression analysis.

RESULTS

The mean age was 71±13 years. Of all patients, 67% had diabetes and 43% were undergoing hemodialysis. The mean follow-up period was 4.3±0.8 years. The overall survival rate was 84.5% and 81.0% at 1 and 3 years, respectively. The Cox regression analysis indicated that high body mass index (odds ratio [OR]: 0.86; 95% confidence interval [CI]: 0.76-0.97; p=0.01), well-nourished (OR: 1.21; 95% CI: 1.01-1.45), and HBOT (OR: 0.05; 95% CI: 0.01-0.26; p<0.001) independently predicted absence of MAEs. For major limb amputation, the ankle-brachial index (OR: 0.2; 95% CI: 0.05-0.86; p=0.03) and HBOT (OR: 0.04; 95% CI: 0.004-0.32; p=0.003) were independent predictors.

CONCLUSIONS

Repetitive, stand-alone HBOT was associated with MAE-free survival and limb salvage in patients with CLTI.

Impact of Red Blood Cell Transfusion on Subsequent Cardiovascular Events in Patients with Acute Heart Failure and Anemia

Red blood cell (RBC) transfusion therapy is often performed in patients with acute heart failure (AHF) and anemia; however, its impact on subsequent cardiovascular events is unclear. We examined whether RBC transfusion influences major adverse cardiovascular events (MACE) after discharge in patients with AHF and anemia.We classified patients with AHF and anemia (nadir hemoglobin level < 10 g/dL) according to whether they received RBC transfusion during hospitalization. The endpoint was MACE (composite of all-cause death, non-fatal acute coronary syndrome/stroke, or heart failure readmission) 180 days after discharge. For survival analysis, we used propensity score matching analysis with the log-rank test. As sensitivity analysis, we performed inverse probability weighting analysis and multivariable Cox regression analysis.Among 448 patients with AHF and anemia (median age, 81 years; male, 55%), 155 received RBC transfusion and 293 did not. The transfused patients had worse clinical features than the non-transfused patients, with lower levels of nadir hemoglobin and serum albumin and a lower estimated glomerular filtration rate. In the propensity-matched cohort of 87 pairs, there was no significant difference in the MACE-free survival rate between the 2 groups (transfused, 73.8% vs. non-transfused, 65.3%; P = 0.317). This result was consistent in the inverse probability weighting analysis (transfused, 76.0% vs. non-transfused, 68.7%; P = 0.512), and RBC transfusion was not significantly associated with post-discharge MACE in the multivariable Cox regression analysis (adjusted hazard ratio: 1.468, 95% confidence interval: 0.976-2.207; P = 0.065).In conclusion, this study suggests that RBC transfusions for anemia may not improve clinical outcomes in patients with AHF.

The association of calcium channel blocker with risk of adverse limb events in patients with chronic limb-threatening ischemia after endovascular treatment

Symptoms of lower-extremity artery disease (LEAD) emerge from impaired vascularization in distal circulation of the extremities. Calcium channel blockers (CCB) can improve distal circulation when used as adjunctive therapy with endovascular treatment (EVT), but few studies have evaluated that. We investigated the relationship between CCB therapy and post-EVT outcomes. Through a consecutive EVT registry, we evaluated those relationships in whole cohort and the following 2 subgroups; the patients suffered from intermittent claudication (IC) or chronic limb-threatening ischemia (CLTI), with adjusting baseline characteristics by propensity score matchings. The primary endpoints were major adverse cardiac and cerebrovascular events (MACCE, a composite endpoint of all death, nonfatal myocardial infarction, and nonfatal stroke), and major adverse limb event (MALE, a composite of major amputation, acute limb ischemia, and surgical reintervention). The group that received CCB had less MALE in whole cohort (HR 0.31; 95% confidence interval (CI) 0.20-0.47), and less MACCE and MALE in CLTI cohort (HR 0.67; 0.50-0.89 and 0.32; 0.20-0.52 respectively) compared to the group that did not receive CCB. The relationships were common in the cohorts with baseline adjustment. MACCE and MALE in IC (HR 1.01; 0.57-1.80 and 0.60; 0.25-1.45, respectively) showed no significant differences both with and without baseline adjustment. CCB use was related to fewer MACCE and MALE events in adjusted patients who underwent EVT, and the trend was more evident, especially in the adjusted CLTI cohort. This study highlights the necessity of future studies regarding CCB. Clinical Trial Registration: URL: https://www.umin.ac.jp ; Unique identifiers: UMIN000015100.

Clinical utility of 67 Gallium-SPECT/CT for determining osteotomy indication in patients with lower-limb osteomyelitis

Standard non-invasive methods for diagnosing and selecting the best treatment for osteomyelitis in patients with multiple chronic conditions remain to be established. We aimed to evaluate the ability of quantitative ⁶⁷ Ga-citrate single-photon emission computed tomography (⁶⁷ Ga-SPECT/CT) to determine the indication for either non-surgical treatment or osteotomy in patients with lower-limb osteomyelitis (LLOM) associated with diabetes mellitus and lower-extremity ischemia, based on monitoring of inflammatory activity in bone tissue. This single-centre prospective study conducted from January 2012 to July 2017 included 90 consecutive patients with suspected LLOM. Regions of interest were drawn on SPECT images during quantification of Ga accumulation. Subsequently, the inflammation-to-background ratio (IBR) was calculated by dividing the maximal accumulated lesion number by the mean number for the distal femur bone marrow of the unaffected side. Osteotomy was performed in 28 of 90 patients (31%). The osteotomy rate was higher for patients with IBR >8.4 (71.4%) than for those with IBR ≤8.4 (5.5%) (p < 0.001, sensitivity: 0.89, specificity: 0.84). In the multivariate Cox regression analysis, IBR >8.4 was an independent risk factor for osteotomy (hazard ratio [HR]: 19.0, 95% confident interval [CI]: 5.6-63.9, p < 0.001). Transcutaneous oxygen tension (TcPO₂ ) was identified as an independent risk factor for lower-limb amputation (HR: 0.96, 95% CI: 0.92-0.99, p = 0.01). The current results indicate that quantitative ⁶⁷ Ga-SPECT/CT is useful for distinguishing patients with LLOM likely to require osteotomy.

Utility of fractional excretion of urea nitrogen in heart failure patients with chronic kidney disease

AIMS

Maintenance of euvolaemia with diuretics is critical in heart failure (HF) patients with chronic kidney disease (CKD); however, it is challenging because no reliable marker of volume status exists. Fractional excretion of urea nitrogen (FEUN) is a useful index of volume status in patients with renal failure. We aimed to examine whether FEUN is a surrogate marker of volume status for risk stratification in HF patients with CKD.

METHODS AND RESULTS

We examined 516 HF patients with CKD (defined as discharge estimated glomerular filtration rate < 60 mL/min/1.73 m² ) whose FEUN was measured at discharge (median age, 80 years; 58% male). The patients were divided into four groups according to quartile FEUN value at discharge: low-FEUN, FEUN ≤ 32.1; medium-FEUN, 32.1 < FEUN ≤ 38.0; high-FEUN, 38.0 < FEUN ≤ 43.7; and extremely-high-FEUN, FEUN > 43.7. FEUN was calculated by the following formula: (urinary urea × serum creatinine) × 100/(serum urea × urinary creatinine). During the 3 year follow-up, 131 HF readmissions occurred. Kaplan-Meier analysis showed that the HF readmission rate was significantly lower in the medium-FEUN group than in the other three groups (log-rank test, P = 0.029). Multivariate Cox regression analysis identified the low-FEUN, high-FEUN, and extremely-high-FEUN values as independent factors associated with post-discharge HF readmission. In the analysis of 130 patients who underwent right heart catheterization during hospitalization, a significant correlation between FEUN value and right atrial pressure was observed (R = 0.243, P = 0.005). Multivariate linear regression analysis revealed that FEUN value at discharge decreased in a dose-dependent manner with loop diuretics.

CONCLUSIONS

In HF patients with CKD, FEUN is a potential marker of volume status for risk stratification of post-discharge HF readmission. Low FEUN value (FEUN ≤ 32.1) may represent intravascular dehydration, whereas high FEUN value (FEUN > 38.0) may represent residual congestion; both of them were independent risk factors for HF readmission. FEUN may be useful to determine euvolaemia and guide fluid management in HF patients with CKD.

Substantial Reduction of Acute Ischemic Mitral Regurgitation Using Impella in AMI Complicated with Cardiogenic Shock

A 77-year-old female presented with loss of consciousness, blood pressure of 90/60 mmHg, and heart rate of 47 bpm. At admission, highly sensitive Trop-T and lactate were elevated, and an electrocardiogram revealed an infero-posterior ST elevation myocardial infarction. Echocardiography revealed a depressed left ventricular ejection fraction with abnormal wall motion in the infero-posterior region and hyperkinetic apical movement along with severe mitral regurgitation (MR). Coronary angiography showed a hypoplastic right coronary artery, 100% thrombotic occlusion of the dominant left circumflex (LCx) artery, and 75% stenosis in the left anterior descending (LAD) artery. Substantial hemodynamic improvement with the reduction of acute ischemic MR was achieved by the initiation of an Impella 2.5, which is a transvalvular axial flow pump, and successful percutaneous coronary intervention (PCI) was conducted with stents to the LCx. The patient was weaned off the Impella 2.5 in 5 days, received staged PCI to LAD, and was later discharged after completion of the staged PCI to LAD.

Comparison of Percutaneous Coronary Intervention Procedures and Outcomes for Recent and Acute ST-Elevation Myocardial Infarction

Although the primary percutaneous coronary intervention (PCI) is an established treatment for acute ST-elevation myocardial infarction (STEMI), relevant guidelines do not recommend it for recent-STEMI cases with a totally occluded infarcted related artery (IRA). However, PCI is allowed in Japan for recent-STEMI cases, but little is known regarding its outcomes. We aimed to examine the details and outcomes of PCI procedures in recent-STEMI cases with a totally occluded IRA and compared the findings with those in acute-STEMI cases.Among the 903 consecutive patients admitted with acute coronary syndrome, 250 were treated with PCI for type I STEMI with a totally occluded IRA. According to the time between symptom onset and diagnosis, patients were divided into the recent-STEMI (n = 32) and acute-STEMI (n = 218) groups. The background, procedure details, and short-term outcomes were analyzed. No significant differences between the groups were noted regarding patient demographics, acute myocardial infarction severity, or IRA distribution. Although the stent number and type were similar, significant differences were observed among PCI procedures, including the number of guidewires used, rate of microcatheter or double-lumen catheter use, and application rate of thrombus aspiration. The thrombolysis rate in the myocardial infarction flow 3-grade post-PCI did not differ significantly between the groups. Both groups had a low frequency of procedure-related complications. The in-hospital mortality rates were 0% and 4.6% in the recent-STEMI and acute-STEMI groups, respectively (P > 0.05).Although recent-STEMI cases required complicated PCI techniques, their safety, success rate, and in-hospital mortality were comparable to those of acute-STEMI cases.

Angioscopic findings 1 year after percutaneous coronary intervention for chronic total occlusion

BACKGROUND

Chronic total occlusion (CTO) is a high-risk factor for stent thrombosis, but little is known about the difference in neointimal healing between CTO and non-CTO lesions regarding implanted stents. We investigated factors affecting neointimal healing after stent implantation for CTO and non-CTO lesions using angioscopy.

METHODS

We retrospectively evaluated 106 stents in 85 consecutive patients between March 2016 and July 2020. Their average age was 68 ± 11 years, and participants (73 male and 12 female) underwent follow-up angiography and angioscopy 1 year after percutaneous coronary intervention (PCI). The stents (n = 106) were divided into three groups according to the lesion status at the previous PCI: CTO (n = 17), acute coronary syndrome (ACS) (n = 35), and stable coronary artery disease without CTO or non-CTO (n = 54).

RESULTS

The neointimal stent coverage grade was significantly lower in the CTO and ACS groups than in the non-CTO group (0.4 ± 0.5, 0.9 ± 0.8, and 1.4 ± 0.8, respectively, p < 0.001). Thrombi were significantly more frequent in CTO and ACS than in non-CTO (71 %, 51 %, and 15 %, respectively, p < 0.001). The yellow grade in CTO was comparable to that in ACS but significantly higher in CTO than in non-CTO (CTO vs. ACS vs. non-CTO 1.5 ± 0.7, 1.4 ± 0.6, and 0.9 ± 0.7, respectively, p = 0.007).

CONCLUSIONS

Delayed healing occurs in stents implanted for CTO lesions. Longer dual-antithrombotic therapy may be beneficial.

Clinical Characteristics and Prognosis of Life-Threatening Acute Myocardial Infarction in Patients Transferred to an Emergency Medical Care Center

Patients with acute myocardial infarction (AMI) triaged as life-threatening are transferred to our emergency medical care center (EMCC). However, data on these patients remain limited. We aimed to compare the characteristics and AMI prognosis of patients transferred to our EMCC with those transferred to our cardiovascular intensive care unit (CICU) using whole and propensity-matched cohorts.We analyzed the data of 256 consecutive AMI patients transferred from the scene to our hospital by ambulance between 2014 and 2017. The EMCC and CICU groups comprised 77 and 179 patients, respectively. There were no significant between-group age or sex differences. Patients in the EMCC group had more disease severity score and had the left main trunk identified as the culprit more frequently (12% versus 0.6%, P < 0.001) than those in the CICU group; however, the number of patients with multiple culprit vessels did not differ. The EMCC group had a longer door-to-reperfusion time (75 [60, 109] minutes versus 60 [40, 86] minutes, P< 0.001) and a higher in-hospital mortality (19% versus 4.5%, P < 0.001), especially from non-cardiac causes (10% versus 0.6%, P < 0.001), than the CICU group. However, peak myocardial creatine phosphokinase did not significantly differ between the groups. The EMCC group had a significantly higher 1-year post-discharge mortality than the CICU group (log-rank, P = 0.032); this trend was maintained after propensity score matching, although the difference was not statistically significant (log-rank, P = 0.094).AMI patients transferred to the EMCC exhibited more severe disease and worse overall in-hospital and non-cardiac mortality than those transferred to the CICU.

Vascular Endothelial Dysfunction in Myeloproliferative Neoplasms and Gene Mutations

Essential thrombocythemia (ET) and polycythemia vera (PV), are common Philadelphia-negative myeloproliferative neoplasms (MPN). Patients with MPN have a high rate of cardiovascular complications and often have acquired JAK2V617F and CALR genetic mutations. In this study, we aimed to analyze vascular endothelial function in patients with MPN.We evaluated 27 outpatients, including 10 patients diagnosed with MPN, flow-mediated dilatation (FMD), and nitroglycerin-mediated dilation (NMD), between September 2014 and August 2016. We measured serum adiponectin, which protects vascular endothelial function, and serum asymmetric dimethyl arginine (ADMA), which inhibits the production of adiponectin. The presence or absence of JAK2V617F and CALR mutations was evaluated in patients with MPN.Venous thrombosis was observed more frequently in patients with MPN than in those without. Seven MPN patients were diagnosed with PV, and 3 MPN patients were diagnosed with ET. JAK2V617F and CALR mutations were found in 5 and 3 MPN patients, respectively. FMD was significantly lower in JAK2V617F-positive MPN patients than in JAK2V617F-negative MPN patients, although NMD, adiponectin, and ADMA were similar in both groups. Adiponectin levels were higher and ADMA levels were lower in CALR-positive MPN patients than in CALR-negative MPN patients. There was no difference in FMD and NMD prevalence between the 2 groups. Furthermore, we had 3 representative MPN patients who were complicated with coronary spasm, possibly caused by MPN-related endothelial dysfunction.We found that patients with MPN presented with endothelial dysfunction, which was related to the presence of genetic mutations and was sometimes associated with cardiovascular disease.

Cyclophosphamide-induced cardiotoxicity at conditioning for allogeneic hematopoietic stem cell transplantation would occur among the patients treated with 120 mg/kg or less

Cyclophosphamide (CY)-induced cardiotoxicity involves rare lethal complications. We previously reported the cardiac events of 811 allogeneic hematopoietic stem cell transplant (allo-HSCT) recipients; 12 out of 811 recipients (1.5%) developed fatal heart failure. The mortality rate was also very high (91.6%, 11/12). CY dose (200 mg/kg or more) was reported as the independent risk factor. The main disease in patients treated with 200 mg/kg or more of CY was severe aplastic anemia (AA). Therefore, we reduced the dose of CY during conditioning for AA (from 200 to 100 mg/kg), and then we analyzed the clinical features of 294 patients who received a total dose of at least 100 mg/kg of CY. We also compared the clinical features between the current study and our previous study. The proportion of patients treated with at least 200 mg/kg of CY was reduced from 4.2% to 0%. However, CY-induced heart failure occurred in four of the 294 patients (1.4%), which was similar to the finding reported in our previous study (1.5%). Two of these four patients received a post-transplant CY (PTCy) regimen (CY 100 mg/kg). All four patients were treated in the cardiac intensive care unit (C-ICU), and two patients survived. In summary, even the CY dose of 120 mg/kg or less would cause cardiotoxicity. We should also carefully monitor patients treated with PTCy, considering the possibility of CY-induced cardiotoxicity. Early diagnosis and ICU management have contributed to improved outcomes.

Feasibility and safety of CT-aided pericardiocentesis from a subxiphoid anterior approach by using fluoroscopy in patients with chronic pericardial effusions

Background

Pericardiocentesis is an essential procedure for the diagnosis and treatment of pericardial effusions. The purpose of this study was to evaluate the feasibility and safety of a subxiphoid anterior approach using fluoroscopy aided by a sagittal axis chest computed tomography (CT) view in comparison with an ultrasound‐guided apical approach in patients with chronic pericardial effusion.

Methods

Among 72 consecutive patients (68.8 ± 14.4 years old, 52 males) with hemodynamically stable chronic pericardial effusions, a total of 85 procedures were retrospectively analyzed. We divided them into two groups according to the site of the approach for the pericardiocentesis.

Results

A subxiphoid anterior approach (n = 53) was performed guided by fluoroscopy. The sagittal axis view of the chest CT was constructed to determine the puncture angle and direction for the subxiphoid anterior approach. An apical approach (n = 32) was performed by ultrasound guidance. The success rates of the anterior and apical approaches were 98.1% and 93.8%, respectively. There were two cases with cardiac perforations in the apical approach group, while no cases developed perforations in the subxiphoid anterior approach group.

Conclusion

The subxiphoid anterior approach for pericardiocentesis was feasible and safe for managing chronic pericardial effusions. A reconstruction of the sagittal axis view of the chest CT imaging was helpful to identify the direction and depth to access the pericardial space from the subxiphoid puncture site before the pericardiocentesis using the lateral fluoroscopic view.

Hemodynamic Collapse Caused by Cardiac Dysfunction and Abdominal Compartment Syndrome in a Patient with Mitochondrial Disease

We herein report a case of mitochondrial disease with heart and intestinal tract involvement resulting in hemodynamic collapse. A 66-year-old woman was transferred to our hospital because of cardiogenic shock. Vasopressors were administered, and a circulatory support device was deployed. However, her hemodynamics did not improve sufficiently, and we detected abdominal compartment syndrome caused by the aggravation of chronic intestinal pseudo-obstruction as a complication. Insertion of a colorectal tube immediately decreased the intra-abdominal pressure, improving the hemodynamics. Finally, we diagnosed her with mitochondrial disease, concluding that the resulting combination of acute heart failure and abdominal compartment syndrome had aggravated the hemodynamics.

Adjunctive Catheter-Directed Thrombolysis during Primary PCI for ST-Segment Elevation Myocardial Infarction with High Thrombus Burden

BACKGROUND

High coronary thrombus burden has been associated with unfavorable outcomes in patients with ST-segment elevation myocardial infarction (STEMI), the optimal management of which has not yet been established.

METHODS

We assessed the adjunctive catheter-directed thrombolysis (CDT) during primary percutaneous coronary intervention (PCI) in patients with STEMI and high thrombus burden. CDT was defined as intracoronary infusion of tissue plasminogen activator (t-PA; monteplase).

RESULTS

Among the 1849 consecutive patients with STEMI, 263 had high thrombus burden. Moreover, 41 patients received t-PA (CDT group), whereas 222 did not receive it (non-CDT group). No significant differences in bleeding complications and in-hospital and long-term mortalities were observed (9.8% vs. 7.2%, p = 0.53; 7.3% vs. 2.3%, p = 0.11; and 12.6% vs. 17.5%, p = 0.84, CDT vs. non-CDT). In patients who underwent antecedent aspiration thrombectomy during PCI (75.6% CDT group and 87.4% non-CDT group), thrombolysis in myocardial infarction grade 2 or 3 flow rate after thrombectomy was significantly lower in the CDT group than in the non-CDT group (32.2% vs. 61.0%, p < 0.01). However, the final rates improved without significant difference (90.3% vs. 97.4%, p = 0.14).

CONCLUSIONS

Adjunctive CDT appears to be tolerated and feasible for high thrombus burden. Particularly, it may be an option in cases with failed aspiration thrombectomy.

Impact of the COVID-19 Pandemic on ST-elevation Myocardial Infarction from a Single-center Experience in Tokyo

Objective The coronavirus disease 2019 (COVID-19) pandemic has had a significant impact on global healthcare systems. Some studies have reported the negative impact of COVID-19 on ST-elevation myocardial infarction (STEMI) patients; however, the impact in Japan remains unclear. This study investigated the impact of the COVID-19 pandemic on STEMI patients admitted to an academic tertiary-care center in Tokyo, Japan. Methods In this retrospective, observational, cohort study, we included 398 consecutive patients who were admitted to our institute from January 1, 2018, to March 10, 2021, and compared the incidence of hospitalization, clinical characteristics, time course, management, and outcomes before and after March 11, 2020, the date when the World Health Organization declared COVID-19 a pandemic. Results There was a 10.7% reduction in hospitalization of STEMI patients during the COVID-19 pandemic compared with that in the previous year (117 vs. 131 cases). During the COVID-19 pandemic, the incidence of late presentation was significantly higher (26.5% vs. 12.1%, p<0.001), and the onset-to-door [241 (IQR: 70-926) vs. 128 (IQR: 66-493) minutes, p=0.028] and door-to-balloon [72 (IQR: 61-128) vs. 60 (IQR: 43-90) min, p<0.001] times were significantly longer than in the previous year. Furthermore, the in-hospital mortality was higher, but the difference was not significant (9.4% vs. 5.0%, p=0.098). Conclusion The COVID-19 pandemic significantly impacted STEMI patients in Tokyo and resulted in a slight decrease in hospitalization, a significant increase in late presentation and treatment delays, and a slight but nonsignificant increase in mortality. In the COVID-19 era, the acute management system for STEMI in Japan must be reviewed.

Clinical Characteristics, Achievement of Secondary Prevention Goals, and Outcomes of Patients with Recurrent Acute Coronary Syndrome

BACKGROUND

Because development of acute coronary syndrome (ACS) worsens the prognosis of patients with coronary artery disease, preventing recurrent ACS is crucial. However, the degree to which secondary prevention treatment goals are achieved in patients with recurrent ACS is unknown.

METHODS

214 consecutive ACS patients were classified as having First ACS (n=182) or Recurrent ACS (n=32), and the clinical characteristics of these groups were compared. Fifteen patients died or developed cardiovascular (CV) events during hospitalization, and the remaining 199 patients were followed from the date of hospital discharge to evaluate subsequent CV events.

RESULTS

Patients in the Recurrent ACS group were older than those in the First ACS group (76.8±10.8 years vs 68.8±13.4 years, p=0.002) and had a higher rate of diabetes mellitus (DM) (65.6% vs 36.8%, p=0.003). The rate of achieving a low-density lipoprotein cholesterol (LDL-C) level of <70 mg/dL in the Recurrent ACS group was only 28.1%, even though 68.8% of these patients were taking statins. An HbA1c level of <7.0% was achieved in 66.7% of patients with recurrent ACS who had been diagnosed with DM. Overall, 12.5% of patients with recurrent ACS had received optimal treatment for secondary prevention. CV events after hospital discharge were noted in 37.9% of the Recurrent ACS group and 21.2% of the First ACS group (log-rank test: p=0.004). However, recurrent ACS was not an independent risk factor for CV events (adjusted hazard ratio: 2.09, 95% confidence interval: 0.95 to 4.63, p=0.068).

CONCLUSION

Optimal treatment for secondary prevention was not achieved in some patients with recurrent ACS, and achievement of the guideline-recommended LDL-C goal for secondary prevention was especially low in this population.

Empagliflozin confers reno-protection in acute myocardial infarction and type 2 diabetes mellitus

AIMS

Although the reno-protective effects of sodium-glucose cotransporter 2 inhibitors are known in patients with heart failure or type 2 diabetes mellitus (T2DM), this effect has not been confirmed in patients with acute myocardial infarction (AMI).

METHODS AND RESULTS

The prospective, multicentre, randomized, double-blind, placebo-controlled EMBODY trial investigated patients with AMI and T2DM in Japan. The eligible patients included adults aged 20 years or older, diagnosed with AMI and T2DM, and who could be discharged within 2-12 weeks after the onset of AMI. One hundred and five patients were randomized (1:1) to receive once daily 10 mg empagliflozin or placebo within 2 weeks of AMI onset. In this sub-analysis, we investigated the time course of renal functional parameters such as serum creatinine levels and estimated glomerular filtration rate (eGFR) from baseline to Weeks 4, 12, and 24. Ninety-six patients (64 ± 11 years, 78 male) were included in the full analysis (n = 46 and 50 in the empagliflozin and placebo groups, respectively). We used serum creatinine and eGFR as indicators of renal function. In the placebo group, eGFR decreased from 66.14 mL/min/1.73 m2 at baseline to 62.77 mL/min/1.73 m2 by Week 24 (P = 0.023) but remained unchanged in the empagliflozin group (from 64.60 to 64.36 mL/min/1.73 m2 , P = 0.843). In the latter group, uric acid improved from 5.8 mg/dL at baseline to 4.9 mg/dL at Week 24 (P < 0.001). In the earlier analysis of 56 patients with eGFR ≥ 60 mL/min/1.73 m2 , the eGFR decreased and the serum creatinine increased from baseline to 24 weeks in the placebo group, significantly different to the empagliflozin group (-6.61 vs. +0.22 mL/min/1.73 m2 , P = 0.008 and +0.063 vs. -0.001 mg/dL, P = 0.030, respectively). The changes in serum creatinine and eGFR from baseline to Week 24 were significantly correlated with those in uric acid in the placebo group (r = 0.664, P < 0.001 and r = -0.675, P < 0.001, respectively) but not in the empagliflozin group.

CONCLUSIONS

Empagliflozin prevented the kidney functional decline in patients with AMI and T2DM, especially those with baseline eGFR ≥ 60 mL/min/1.73 m2 . Early administration of sodium-glucose cotransporter 2 inhibitors in these patients is considered desirable for renal protection.

A novel gradient and multilayered sheet with a silk fibroin/polyvinyl alcohol core-shell structure for bioabsorbable arterial grafts

Bioabsorbable arterial grafts can potentially improve patency and neovessel formation; however, their application in clinical settings has not been realized. In this study, we developed bioabsorbable gradient sheets based on silk fibroin (SF) and polyvinyl alcohol (PVA) with a core-shell nanofibrous structure. This gradient sheet was expected to promote vascular remodeling while we maintained its physical properties and a gradual degrading process from the luminal surface. ESP was conducted at various flow rates for SF and PVA to achieve the multilayer gradient structure. Furthermore, the elasticity of the gradient sheet could be increased by increasing the PVA flow rate; however, this reduced the tensile strength of the core-shell fibers. Notably, the physical properties of the gradient sheet did not degrade even after 7 days of immersion in a phosphate buffer saline solution, which indicates that the structure could maintain its structural integrity while resisting arterial pressure. In vitro experiments revealed that the number of endothelial cells attached to the SF/PVA sheet was notably higher than that on the cell-culture dish. The gradient sheets were implanted in rat abdominal aortas and explanted after 14 days to confirm acute-phase patency and vascular remodeling. The gradient sheets constructed with SF composed of polyurethane and PVA improved the ease of handling of the material, and these sheets resulted in a favorable vascular remodeling outcome. Our results strongly suggest that the SF/PVA-based gradient sheets described in this study can serve as a novel design for bioabsorbable arterial grafts upon further modifications.

Effect of Empagliflozin Versus Placebo on Body Fluid Balance in Patients With Acute Myocardial Infarction and Type 2 Diabetes Mellitus: Subgroup Analysis of the EMBODY Trial

BACKGROUND

The development of heart failure is associated with fluid balance, including that of extracellular water (ECW) and intracellular water (ICW). This study determined whether sodium-glucose cotransporter 2 inhibitors affect fluid balance and improve heart failure in patients after acute myocardial infarction.

METHODS AND RESULTS

EMBODY was a prospective, randomized, double-blinded, placebo-controlled trial of Japanese patients with acute myocardial infarction and type 2 diabetes. Overall, 55 patients who underwent bioelectrical impedance analysis were randomized to receive once daily 10 mg empagliflozin or placebo 2 weeks after acute myocardial infarction onset. We investigated the time course of body fluid balance measured using the bioelectrical impedance analysis device, InBody. The primary end points were changes in body fluid balance from weeks 0 to 24. Changes between baseline and week 24 in the empagliflozin and placebo groups were -0.21 L (P = .127) and +0.40 L (P = .001) in ECW (P = .001) and -0.23 L (P = .264) and +0.74 L (P < .001) in ICW (P < .001), respectively. In a stratified analysis, the rise in ECW and ICW was significantly attenuated in the empagliflozin group in contrast to the placebo group in participants with a body mass index of 25 or higher but not in those with a body mass index of less than 25.

CONCLUSIONS

Early sodium-glucose cotransporter 2 inhibitor administration may attenuate changes in ECW and ICW.

Effect of Empagliflozin Versus Placebo on Plasma Volume Status in Patients with Acute Myocardial Infarction and Type 2 Diabetes Mellitus

INTRODUCTION

Plasma volume status (PVS), a parameter of the discrepancy between actual plasma volume (PV) and ideal PV, has been recently evaluated as a prognostic marker in patients with heart failure. This subgroup analysis of the EMBODY trial was designed to determine whether a sodium-glucose cotransporter 2 (SGLT2) inhibitor affects the alleviation of heart failure and improvement of PVS in patients after acute myocardial infarction (AMI) with congestive heart failure (CHF).

METHODS

The EMBODY trial was a prospective, multicenter, randomized, double-blind, placebo-controlled trial to identify the effect of an SGLT2 inhibitor on cardiac sympathetic hyperactivity in patients with AMI and type 2 diabetes mellitus (T2DM) in Japan. In total, 105 patients were randomized (1:1) to receive 10 mg empagliflozin or a placebo (once daily), 2 weeks after the onset of AMI. In this subanalysis, we investigated the time-course of PVS at baseline and weeks 4, 12, and 24.

RESULTS

Overall, 96 patients were included in the subgroup analysis set (age 64.3 ± 10.9 years, 80.2% men; 46 in the empagliflozin group and 50 in the placebo group). Body weight and PVS decreased in the empagliflozin group compared with the placebo group at 24 weeks (- 2.2 vs. + 0.1 kg, P < 0.001, and - 5.1 vs. - 0.3%, P < 0.001, respectively). Decreased PVS, defined as a change in PVS of < - 4.5%, was associated with the administration of empagliflozin (odds ratio 2.61, 95% confidence interval 1.11-6.15, P = 0.028). N-terminal pro b-type natriuretic peptide levels decreased in both the empagliflozin and placebo groups (1028.7-370.3 pg/mL, P < 0.001, and 1270.6-673.7 pg/mL, P < 0.01, respectively).

CONCLUSION

Empagliflozin reduced the body weight and PVS. Early SGLT2 inhibitor administration in patients with AMI, CHF, and T2DM can therefore be effective in reducing the body weight and PVS.

TRIAL REGISTRATION

UMIN 000030158.

Relationship Between Procedural Right Bundle Branch Block and 1-Year Outcome After Alcohol Septal Ablation for Hypertrophic Obstructive Cardiomyopathy - A Retrospective Study

BACKGROUND

Alcohol septal ablation (ASA) is a treatment option in patients with drug-refractory symptomatic hypertrophic obstructive cardiomyopathy (HOCM). In many patients, right bundle branch block (RBBB) develops during ASA because septal branches supply the right bundle branch. However, the clinical significance of procedural RBBB is uncertain.Methods and Results:We retrospectively reviewed 184 consecutive patients with HOCM who underwent ASA. We excluded 40 patients with pre-existing RBBB (n=10), prior pacemaker implantation (n=15), mid-ventricular obstruction type (n=10), and those lost to follow-up (n=5), leaving 144 patients for analysis. Patients were divided into 2 groups according to the development (n=95) or not (n=49) of procedural RBBB. ASA conferred significant decreases in the left ventricular pressure gradient (LVPG) in both the RBBB and no-RBBB group (from 74±48 to 27±27 mmHg [P<0.001] and from 75±45 to 31±33 mmHg [P<0.001], respectively). None of the RBBB patients developed further conduction system disturbances. The percentage reduction in LVPG at 1 year after the procedure was significantly greater in the RBBB than no-RBBB group (66±24% vs. 49±45%; P=0.035). Procedural RBBB was not associated with pacemaker implantation after ASA, but was associated with reduction in repeat ASA (odds ratio 0.34; 95% confidence interval 0.13-0.92; P=0.045).

CONCLUSIONS

Although RBBB frequently occurs during the ASA procedure, it does not adversely affect clinical outcomes.

Non-cardiovascular disorders in a contemporary cardiovascular intensive care unit in Japan

BACKGROUND

In the modern US cardiovascular intensive care unit (CICU), the incidence of non-cardiovascular disorders has increased and non-cardiovascular disorders are associated with an increase in morbidity and mortality. In Japan, however, data regarding the association between non-cardiovascular disorders and outcomes in the CICU are limited.

METHODS

This study examined 490 consecutive admissions to a closed CICU at the Nippon Medical School Hospital from January to December 2017. Characteristics, diagnoses, treatments, and outcomes of admitted patients were identified.

RESULTS

The most common primary diagnosis was acute coronary syndrome (50.4%), followed by acute heart failure (20.0%), arrhythmia (6.7%), and non-cardiovascular diseases (3.7%). The mortality rate and median length of stay (LOS) in the CICU were 4.7% and 4 (interquartile range, 2-8) days, respectively. Of all patients, 42.2% (n = 207) developed non-cardiovascular complications such as acute respiratory failure, acute kidney injury, or sepsis during CICU stay. Multivariate logistic regression analysis revealed that acute respiratory failure and sepsis were significantly associated with mortality in the CICU (odds ratio, 11.014 and 25.678, respectively; both p<0.05). The multiple linear regression analysis showed that acute kidney injury was significantly associated with LOS in the CICU (β=0.144, p = 0.002).

CONCLUSIONS

Approximately half of patients admitted to the CICU had non-cardiovascular disorders including non-cardiovascular disease and non-cardiovascular complications, which were significantly associated with mortality and LOS in the CICU.

Characteristics of the Inter-arm Difference in Blood Pressure in Acute Aortic Dissection

BACKGROUND

An inter-arm difference in blood pressure (IADBP) is characteristic of acute aortic dissection (AAD), but which arm shows lower blood pressure (BP) and the mechanism of IADBP has not been fully elucidatedMethods: We identified consecutive patients with chest and/or back pain and suspected acute cardiovascular disease whose BP had been measured in both arms. We retrospectively compared the characteristics of such patients with AAD (n=93) to those without (non-AAD group, n=122). Additionally, we separately compared patients with type A AAD (TAAD group, n=58) or type B AAD (TBAD group, n=35) to non-AAD group. Characteristics included in these comparisons were patients' backgrounds and IADBP-related factors such as systolic BP (SBP) in the right arm (R) and left arm (L), R-L or L-R as the IADBP. Computed tomography (CT) findings of AD extending to the brachiocephalic artery (BCA) and/or left subclavian artery (LSCA) were examined in patients having IADBP.

RESULTS

In the TAAD group, the prevalence of R<130mmHg (38%-vs.-19%, p=0.009), L-R>15mmHg (19%-vs.-8%, p=0.047), L-R>20mmHg (14%-vs.-4%, p=0.029) was higher than in the non-AAD group. Multivariate analysis showed L-R>15mmHg with R<130mmHg was independently associated with TAAD (OR 25.97, 95% CI 2.45-275.67, p=0.007). However, IADBP-related factors were not associated with TBAD. AAD patients with L-R>20mmHg were all TAAD, and all aortic dissection extended to BCA just before the right common carotid artery on CT.

CONCLUSIONS

IADBP was characterized by R<L with low R in TAAD, but was not associated with TBAD.

Gastrointestinal bleeding increases the risk of subsequent cardiovascular events in patients with acute cardiovascular diseases requiring intensive care

Gastrointestinal (GI) bleeding worsens the outcomes of critically ill patients in the intensive care unit (ICU). Owing to a lack of corresponding data, we aimed to investigate whether GI bleeding during cardiovascular-ICU (C-ICU) admission in acute cardiovascular (CV) disease patients is a risk factor for subsequent CV events. Totally, 492 consecutive C-ICU patients (40.9% acute coronary syndrome, 22.8% heart failure) were grouped into GI bleeding (n = 27; 12 upper GI and 15 lower GI) and non-GI bleeding (n = 465) groups. Thirty-nine patients died or developed CV events during hospitalization, and 453 were followed up from the date of C-ICU discharge to evaluate subsequent major adverse CV events. The GI bleeding group had a higher Acute Physiology and Chronic Health Evaluation II score (20.2 ± 8.2 vs. 15.1 ± 6.8, p < 0.001), higher frequency of mechanical ventilator use (29.6% vs. 13.1%, p = 0.039), and longer C-ICU admission duration (8 [5–16] days vs. 5 [3–8] days, p < 0.001) than the non-GI bleeding group. The in-hospital mortality rate did not differ between the groups. Of those who were followed-up, CV events after C-ICU discharge were identified in 34.6% and 14.3% of patients in the GI and non-GI bleeding groups, respectively, during a median follow-up period of 228 days (log rank, p < 0.001). GI bleeding was an independent risk factor for subsequent CV events (adjusted hazard ratio: 2.23, 95% confidence interval: 1.06–4.71; p = 0.035). GI bleeding during C-ICU admission was independently associated with subsequent CV events in such settings.

Effects of empagliflozin versus placebo on cardiac sympathetic activity in acute myocardial infarction patients with type 2 diabetes mellitus: the EMBODY trial

Background

Protection from lethal ventricular arrhythmias leading to sudden cardiac death (SCD) is a crucial challenge after acute myocardial infarction (AMI). Cardiac sympathetic and parasympathetic activity can be noninvasively assessed using heart rate variability (HRV) and heart rate turbulence (HRT). The EMBODY trial was designed to determine whether the Sodium–glucose cotransporter 2 (SGLT2) inhibitor improves cardiac nerve activity.

Methods

This prospective, multicenter, randomized, double-blind, placebo-controlled trial included patients with AMI and type 2 diabetes mellitus (T2DM) in Japan; 105 patients were randomized (1:1) to receive once-daily 10-mg empagliflozin or placebo. The primary endpoints were changes in HRV, e.g., the standard deviation of all 5-min mean normal RR intervals (SDANN) and the low-frequency–to–high-frequency (LF/HF) ratio from baseline to 24 weeks. Secondary endpoints were changes in other sudden cardiac death (SCD) surrogate markers such as HRT.

Results

Overall, 96 patients were included (46, empagliflozin group; 50, placebo group). The changes in SDANN were + 11.6 and + 9.1 ms in the empagliflozin (P = 0.02) and placebo groups (P = 0.06), respectively. Change in LF/HF ratio was – 0.57 and – 0.17 in the empagliflozin (P = 0.01) and placebo groups (P = 0.43), respectively. Significant improvement was noted in HRT only in the empagliflozin group (P = 0.01). Whereas intergroup comparison on HRV and HRT showed no significant difference between the empagliflozin and placebo groups. Compared with the placebo group, the empagliflozin group showed significant decreases in body weight, systolic blood pressure, and uric acid. In the empagliflozin group, no adverse events were observed.

Conclusions

This is the first randomized clinical data to evaluate the effect of empagliflozin on cardiac sympathetic and parasympathetic activity in patients with T2DM and AMI. Early SGLT2 inhibitor administration in AMI patients with T2DM might be effective in improving cardiac nerve activity without any adverse events.

Trial Registration: The EMBODY trial was registered by the UMIN in November 2017 (ID: 000030158). UMIN000030158; https://upload.umin.ac.jp/cgi-open-bin/ctr_e/ctr_view.cgi?recptno=R000034442.

Imatinib attenuates neotissue formation during vascular remodeling in an arterial bioresorbable vascular graft

Background

Bioresorbable vascular grafts (BVGs) can transform biologically into active blood vessels and represent an alternative to traditional synthetic conduits, which are prone to complications such as infection and thrombosis. Although platelet-derived growth factors and c-Kit positive cells play an important role in smooth muscle cell (SMC) migration and proliferation in vascular injury, atherosclerosis, or allograft, their roles in the vascular remodeling process of an arterial BVG remains unknown. Thus, we assessed the neottisue formation on arterial BVG remodeling by administrating imatinib, which is both a platelet-derived growth factor receptor kinase inhibitor and c-Kit receptor kinase inhibitor, in a murine model.

Methods

BVGs were composed of an inner poly(_L-lactic-co-ε-caprolactone) copolymer sponge layer and an outer electrospun poly(_L-lactic acid) nanofiber layer, which were implanted into the infrarenal abdominal aortas of C57BL/6 mice. After graft implantation, saline or 100 mg/kg of imatinib was administrated intraperitoneally daily for 2 weeks (n = 20 per group). Five mice in each group were scheduled to be humanely killed at 3 weeks and 15 at 8 weeks, and BVGs were explanted for histologic assessments.

Results

Graft patency during the 8-week observational period was not significantly different between groups (control, 86.7% vs imatinib, 80.0%; P > .999). Neotissue formation consisting of endothelialization, smooth muscle proliferation, and deposition of collagen and elastin was not observed in either group at 3 weeks. Similar endothelialization was achieved in both groups at 8 weeks, but thickness and percent area of neotissue formation were significantly higher in the control group than in the imatinib group, (thickness, 30.1 ± 7.2 μm vs 19.6 ± 4.5 μm [P = .001]; percent area, 9.8 ± 2.7% vs 6.8 ± 1.8% [P = .005]). Furthermore, SMC layer and deposition of collagen and elastin were better organized at 8 weeks in the control group compared with the imatinib group. The thickness of SMC layer and collagen fiber area were significantly greater at 8 weeks in the control group than in the imatinib group (P < .001 and P = .026, respectively). Because there was no difference in the inner diameter of explanted BVGs (831.7 ± 63.4 μm vs 841.8 ± 41.9 μm; P = .689), neotissue formation was thought to advance toward the outer portion of the BVG with degradation of the polymer scaffold.

Conclusions

Imatinib attenuates neotissue formation during vascular remodeling in arterial bioresorbable vascular grafts (BVGs) by inhibiting SMC layer formation and extracellular matrix deposition.

This study demonstrated that imatinib attenuated neotissue formation during vascular remodeling in arterial Bioresorbable vascular graft (BVG) by inhibiting smooth muscle cell formation and extracellular matrix deposition. In addition, as imatinib did not modify the inner diameter of BVG, neotissue advanced circumferentially toward the outer portion of the neovessel. Currently, BVGs have not yet been clinically applied to the arterial circulation. The results of this study are helpful for the design of BVG that can achieve an optimal balance between polymer degradation and neotissue formation.

P889Clinical significance of four-dimensional flow magnetic resonance imaging measurement of turbulent kinetic energy for hypertrophic obstructive cardiomyopathy

Purpose

The aims of this study were to investigate the relationship between TKE value and echocardiographic findings, clinical symptoms and evaluate the usefulness of 4D flow MRI to distinguish hypertrophic obstructive cardiomyopathy (HOCM) from non-obstructive HCM (HNCM).

Methods

From April 2018 to January 2019, 18 hypertrophic obstructive cardiomyopathy (HOCM) and 14 non-obstructive HCM (HNCM) patients underwent 4D flow MRI. We investigated TKE value calculated by 4D flow MRI, echocardiographic findings; left ventricular pressure gradient (LVPG), mitral regurgitation (MR) and clinical symptom.

Results

HOCM was defined by the 30 mmHg or greater of LVPG (HOCM: 87.7±47.3 mmHg, HNCM; 5.8±7.8 mmHg, p<0.001). TKE value in HOCM patients was significantly higher than HNCM (14.2±4.7 mJ vs. 9.0±4.6 mJ, p<0.001). There was a significant positive linear relationship between TKE value and LVPG (r=0.488, p=0.046). There was no significant relationship between NYHA functional class and TKE value (p=0.47) or LVPG (p=0.11). ROC curve analysis showed that optimal cut off point of TKE value between HOCM and HNCM (sensitivity=95%, specificity=62%, AUC=0.798) was 9.270 mJ. Multiple linear regression showed that there was significant association between severity of MR and combination of TKE (p=0.015) or LVPG (p–=0.012). A representative case demonstrated the significant reduction of TKE value 1 week and 3 months after alcohol septal reduction compared with that obtained before the procedure (Figure)

Conclusion

Our findings suggest that 4D Flow MRI can effectively evaluate the energy dissipation associated with LV outflow tract obstruction and TKE value is useful for identifying HOCM. TKE value also can be the novel parameter of the severity of HOCM.

P3852Twenty-eight-year temporal trends of treatment strategy and short-term outcomes in patients with high-risk pulmonary embolism: impact of ESC guidelines changes

Background

Thrombolysis has been recommended for high-risk pulmonary embolism (PE) in ESC guidelines, used as a reference in Japan. Recently, indication of thrombolysis for acute PE has been limited with recent guideline revision. Little is known regarding trends of treatment strategy and mortality in high-risk PE patients.

Purpose

To clarify temporal trends of treatment strategy and short-term outcomes in high-risk PE patients.

Methods

A retrospective analysis of therapeutic interventions and short-term outcomes was performed for 52 consecutive high-risk PE patients including cardiac arrest. According to timing of ESC guidelines update (2000, 2008 and 2014), patients were divided into four time periods: 1992 to 2000, 2001 to 2008, 2009 to 2014, and 2015 to 2018.

Results

Mean age and proportion of male were not different over the period. Nosocomial case decreased from 100% to 25% (p<0.01). Postoperative cases (relative contraindication for thrombolysis) included 43% of all patients. Cardiac arrest and VA-ECMO use were 42% and 21% of all patients. Any thrombolytic therapy including catheter-directed intervention showed a non-significant decrease trend (92%-87%-71%-44%, p=0.067). Temporary or retrieval IVC filter insertion showed a significant downward trend (36%-80%-54%-22%, p=0.025). The entire study 30-day mortality was 23%. There was no significant difference in 30-day mortality over the periods (14%-27%-14%-44%, p=0.303). However, major bleeding decreased significantly (71%-40%-7%-22%, p=0.004) (Table).

Table 1 1992–2000 (n=14) 2001–2008 (n=15) 2009–2014 (n=14) 2015–2018 (n=9) p Age (years) 54±12 59±17 64±13 65±16 0.224 Male 29% 13% 29% 44% 0.269 Any thrombolytic therapy 92% 87% 71% 44% 0.067 Catheter-directed therapy 86% 87% 71% 0% <0.01   with thrombolytics (92%) (83%) (90%)   without thromboloytics (8%) (17%) (10%) Only intravenous thrombolysis 8% 7% 7% 44% 0.038 Temporary/retrieval IVC filter 36% 80% 54% 22% 0.025 ICU stay (days) 15±14 10±18 5±4 8±8 0.206 30-day mortality 14% 27% 14% 44% 0.303 Major bleeding 71% 40% 7% 22% 0.004

Conclusion

The temporal analysis identified a decreased trend in any thrombolytic therapy and IVC filter insertion in high-risk PE. The study also found a decreasing trend in major bleeding.

Differential outcomes of venous and arterial tissue engineered vascular grafts highlight the importance of coupling long-term implantation studies with computational modeling

Electrospinning is commonly used to generate polymeric scaffolds for tissue engineering. Using this approach, we developed a small-diameter tissue engineered vascular graft (TEVG) composed of poly-ε-caprolactone-co-l-lactic acid (PCLA) fibers and longitudinally assessed its performance within both the venous and arterial circulations of immunodeficient (SCID/bg) mice. Based on in vitro analysis demonstrating complete loss of graft strength by 12 weeks, we evaluated neovessel formation in vivo over 6-, 12- and 24-week periods. Mid-term observations indicated physiologic graft function, characterized by 100% patency and luminal matching with adjoining native vessel in both the venous and arterial circulations. An active and robust remodeling process was characterized by a confluent endothelial cell monolayer, macrophage infiltrate, and extracellular matrix deposition and remodeling. Long-term follow-up of venous TEVGs at 24 weeks revealed viable neovessel formation beyond graft degradation when implanted in this high flow, low-pressure environment. Arterial TEVGs experienced catastrophic graft failure due to aneurysmal dilatation and rupture after 14 weeks. Scaffold parameters such as porosity, fiber diameter, and degradation rate informed a previously described computational model of vascular growth and remodeling, and simulations predicted the gross differential performance of the venous and arterial TEVGs over the 24-week time course. Taken together, these results highlight the requirement for in vivo implantation studies to extend past the critical time period of polymer degradation, the importance of differential neotissue deposition relative to the mechanical (pressure) environment, and further support the utility of predictive modeling in the design, use, and evaluation of TEVGs in vivo. STATEMENT OF SIGNIFICANCE: Herein, we apply a biodegradable electrospun vascular graft to the arterial and venous circulations of the mouse and follow recipients beyond the point of polymer degradation. While venous implants formed viable neovessels, arterial grafts experienced catastrophic rupture due to aneurysmal dilation. We then inform a previously developed computational model of tissue engineered vascular graft growth and remodeling with parameters specific to the electrospun scaffolds utilized in this study. Remarkably, model simulations predict the differential performance of the venous and arterial constructs over 24 weeks. We conclude that computational simulations should inform the rational selection of scaffold parameters to fabricate tissue engineered vascular grafts that must be followed in vivo over time courses extending beyond polymer degradation.

Bone marrow-derived mononuclear cell seeded bioresorbable vascular graft improves acute graft patency by inhibiting thrombus formation via platelet adhesion

Background:

Acute thrombosis is a crucial cause of bioresorbable vascular graft (BVG) failure. Bone marrow-derived mononuclear cell (BM-MNC)-seeded BVGs demonstrated high graft patency, however, the effect of seeded BM-MNCs against thrombosis remains to be elucidated. Thus, we evaluated an antithrombotic effect of BM-MNC-seeding and utilized platelet-depletion mouse models to evaluate the contribution of platelets to acute thrombosis of BVGs.

Methods and results:

BVGs were composed of poly (glycolic acid) mesh sealed with poly (l-lactideco-ε-caprolactone). BM-MNC-seeded BVGs and unseeded BVGs were implanted to wild type C57BL/6 mice (n = 10/group) as inferior vena cava interposition conduits. To evaluate platelet effect on acute thrombosis, c-Mpl^–/– mice and Pf4-Cre⁺; iDTR mice with decreased platelet number were also implanted with unseeded BVGs (n = 10/group). BVG patency was evaluated at 2, 4, and 8 weeks by ultrasound. BM-MNC-seeded BVGs demonstrated a significantly higher patency rate than unseeded BVGs during the acute phase (2-week, 90% vs 30%, p = .020), and patency rates of these grafts were sustained until week 8. Similar to BM-MNC-seeded BVGs, C-Mpl^−/− and Pf4-Cre⁺; iDTR mice also showed favorable graft patency (2-week, 90% and 80%, respectively) during the acute phase. However, the patency rate of Pf4-Cre⁺; iDTR mice decreased gradually after DTR treatment as platelet number recovered to baseline. An in vitro study revealed BM-MNC-seeding significantly inhibited platelet adhesion to BVGs compared to unseeded BVGs, (1.75 ± 0.45 vs 8.69 ± 0.68 × 10³ platelets/mm², p < .001).

Conclusions:

BM-MNC-seeding and the reduction in platelet number prevented BVG thrombosis and improved BVG patency, and those results might be caused by inhibiting platelet adhesion to the BVG.

Effect of Empagliflozin Versus Placebo on Cardiac Sympathetic Activity in Acute Myocardial Infarction Patients with Type 2 Diabetes Mellitus: Rationale

INTRODUCTION

Protection from lethal ventricular arrhythmias leading to sudden cardiac death is one of the most important problems after myocardial infarction. Cardiac sympathetic hyperactivity is related to poor prognosis and fatal arrhythmias and can be non-invasively assessed with heart rate variability, heart rate turbulence, T-wave alternans, late potentials, and ¹²³I-meta-iodobenzylguanide (¹²³I-MIBG) scintigraphy. Sodium glucose cotransporter 2 (SGLT2) inhibitors potentially reduce sympathetic nervous system activity that is augmented in part due to the stimulatory effect of hyperglycemia. The EMBODY trial is designed to determine whether the suppression of cardiac sympathetic activity induced by the SGLT2 inhibitor is accompanied by protection against adverse cardiovascular outcomes.

METHODS

The EMBODY trial is a prospective, multicenter, randomized, double-blind, placebo-controlled trial in patients with acute MI and type 2 diabetes in Japan. A total of 98 patients will be randomized (1:1) to receive once-daily placebo or empagliflozin, an SGLT2 inhibitor, 10 mg. The primary end point is the change from baseline to 24 weeks in heart rate variability. Secondary end points include the change from baseline for other sudden cardiac death surrogate-markers such as heart rate turbulence, T-wave alternans, late potentials, and ¹²³I-MIBG scintigraphy imaging. Adverse effects will be evaluated throughout the trial period.

PLANNED OUTCOMES

The EMBODY trial will evaluate the potential cardioprotective effect of empagliflozin and will provide additional important new data regarding its preventative effects on sudden cardiac death.

TRIAL REGISTRATION

Unique Trial Number, UMIN000030158 ( https://upload.umin.ac.jp/cgi-open-bin/ctr/ctr_view.cgi?recptno=R000034442 ).

FUNDING

Nippon Boehringer Ingelheim and Eli Lilly and Company.

Differentiation of circulating neural progenitor cells in vitro on fibrin-based composite -matrix involves Wnt- β-catenin-like signaling

Isolation of progenitors with regenerative potential and their in vitro induction to specific lineage may be necessary for effective cell transplantation outcome. Earlier, we standardized specific niche for derivation of neural progenitor cells (NPCs) from circulating mononuclear cells to neural like cells (NLC) in vitro, for applications in neural regeneration. The current study analysed the prospective involvement of signaling mechanism for in vitro lineage commitment of circulating NPCs. Preferred mechanism selected was Wnt-like signaling because this is one of the pathways implicated in the central nervous system (CNS) development and homeostasis. We sought to determine the activation of Wnt3a-specific genes in the standardized NPC culture system. To start with, it was found that when standardized NPC culture niche was supplemented with Wnt 3a protein, no additional morphological changes happen. Chemical inhibitors of the pathway retarded NPC to NLC conversion both in the absence and presence of supplemented Wnt-3a. In earlier studies, involvement of the niche constituents- fibronectin (FN), laminin (La) and fibrin (Fib)- for NPC growth and differentiation was established. In an attempt to study the role of these adhesive proteins by adding antibodies against FN, La & Fib together, molecular level signaling changes seen were comparable to that occur in response to Wnt3a chemical inhibitor. Therefore, induction of Wnt 3a-like signal from the matrix-dependent niche constituents may be implicated in the differentiation of NPC to NLC. The results substantiate the potential applications of the fibrin-based composite niche in neural engineering for regeneration.

Novel application and serial evaluation of tissue-engineered portal vein grafts in a murine model

AIM

Surgical management of pediatric extrahepatic portal vein obstruction requires meso-Rex bypass using autologous or synthetic grafts. Tissue-engineered vascular grafts (TEVGs) provide an alternative, but no validated animal models using portal TEVGs exist. Herein, we preclinically assess TEVGs as portal vein bypass grafts.

MATERIALS & METHODS

TEVGs were implanted as portal vein interposition conduits in SCID-beige mice, monitored by ultrasound and micro-computed tomography, and histologically assessed postmortem at 12 months.

RESULTS

TEVGs remained patent for 12 months. Histologic analysis demonstrated formation of neovessels that resembled native portal veins, with similar content of smooth muscle cells, collagen type III and elastin.

CONCLUSION

TEVGs are feasible portal vein conduits in a murine model. Further preclinical evaluation of TEVGs may facilitate pediatric clinical translation.

A novel application of the culotte stent technique to bail out a jailed common iliac artery

Implanting a self-expandable stent at the ostium of the common iliac artery (CIA) may lead to coverage of the orifice of the contralateral CIA. Here, we describe a novel application of the culotte stent technique using a balloon-expandable stent to bail out an ostial stenotic legion of a jailed CIA due to prior self-expandable stent placement. The bilateral CIAs were revascularized by culotte stenting, and patency of the stents was confirmed 3 years after the procedure. The culotte stent technique was successfully applied to an ostial stenotic lesion of a jailed CIA.

Tropoelastin inhibits intimal hyperplasia of mouse bioresorbable arterial vascular grafts

Neointimal hyperplasia, which results from the activation, proliferation and migration of vascular smooth muscle cells (SMCs), is a detrimental condition for vascular stents or vascular grafts that leads to stenosis. Preventing neointimal hyperplasia of vascular grafts is critically important for the success of arterial vascular grafts. We hypothesized that tropoelastin seeding onto the luminal surface of the graft would prevent neointimal hyperplasia through suppressing neointimal smooth muscle cell proliferation. In this study, we investigated the efficacy of tropoelastin seeding in preventing neointimal hyperplasia of bioresorbable arterial vascular grafts. Poly (glycolic acid) (PGA) fiber mesh coated with poly (l-lactic-co-ε-caprolactone) (PLCL) scaffolds reinforced by poly (l-lactic acid) (PLA) nano-fibers were prepared as bioresorbable arterial grafts. Tropoelastin was then seeded onto the luminal surface of the grafts. Tropoelastin significantly reduced the thickness of the intimal layer. This effect was mainly due to a substantial reduction the number of cells that stained positive for SMC (α-SMA) and PCNA in the vessel walls. Mature elastin and collagen type I and III were unchanged with tropoelastin treatment. This study demonstrates that tropoelastin seeding is beneficial in preventing SMC proliferation and neointimal hyperplasia in bioresorbable arterial vascular grafts.

STATEMENT OF SIGNIFICANCE

Small resorbable vascular grafts can block due to the over-proliferation of smooth muscle cells in neointimal hyperplasia. We show here that the proliferation of these cells is restricted in this type of graft. This is achieved with a simple dip, non-covalent coating of tropoelastin. It is in principle amendable to other grafts and is therefore an attractive process. This study is particularly significant because: (1) it shows that smooth muscle cell proliferation can be reduced while still accommodating the growth of endothelial cells, (2) small vascular grafts with an internal diameter of less than 1mm are amenable to this process, and (3) this process works for resorbable grafts.

Deconstructing the Tissue Engineered Vascular Graft: Evaluating Scaffold Pre-Wetting, Conditioned Media Incubation, and Determining the Optimal Mononuclear Cell Source

Stenosis limits widespread use of tissue-engineered vascular grafts (TEVGs), and bone marrow mononuclear cell (BM-MNC) seeding attenuates this complication. Yet seeding is a multistep process, and the singular effects of each component are unknown. We investigated which components of the clinical seeding protocol confer graft patency and sought to identify the optimal MNC source. Scaffolds composed of polyglycolic acid and ε-caprolactone/ι-lactic acid underwent conditioned media (CM) incubation (n = 25) and syngeneic BM-MNC (n = 9) or peripheral blood (PB)-MNC (n = 20) seeding. TEVGs were implanted for 2 weeks in the mouse IVC. CM incubation and PB-MNC seeding did not increase graft patency compared to control scaffolds prewet with PBS (n = 10), while BM-MNC seeding reduced stenosis by suppressing inflammation and smooth muscle cell, myofibroblast, and pericyte proliferation. IL-1β, IL-6, and TNFα were elevated in the seeded BM-MNC supernatant. Further, BM-MNC seeding reduced platelet activation in a dose-dependent manner, possibly contributing to TEVG patency.

Novel Bioresorbable Vascular Graft With Sponge-Type Scaffold as a Small-Diameter Arterial Graft

BACKGROUND

Current commercialized small-diameter arterial grafts have not shown clinical effectiveness due to their poor patency rates. The present study evaluated the feasibility of an arterial bioresorbable vascular graft, which has a porous sponge-type scaffold, as a small-diameter arterial conduit.

METHODS

The grafts were constructed by a 50:50 poly (1-lactic-co-ε-caprolactone) copolymer (PLCL) scaffold reinforced by a poly (1-lactic acid) (PLA) nanofiber. The pore size of the PLCL scaffold was adjusted to a small size (12.8 ± 1.85 μm) or a large size (28.5 ± 5.25 μm). We compared the difference in cellular infiltration, followed by tissue remodeling, between the groups. The grafts were implanted in 8- to 10-week-old female mice (n = 15 in each group) as infrarenal aortic interposition conduits. Animals were monitored for 8 weeks and euthanized to evaluate neotissue formation.

RESULTS

No aneurysmal change or graft rupture was observed in either group. Histologic assessment demonstrated favorable cell infiltration into scaffolds, neointimal formation with endothelialization, smooth muscle cell proliferation, and elastin deposition in both groups. No significant difference was observed between the groups. Immunohistochemical characterization with anti-F4/80 antibody demonstrated that macrophage infiltration into the grafts occurred in both groups. Staining for M1 and M2, which are the two major macrophage phenotypes, showed no significant difference between groups.

CONCLUSIONS

Our novel bioresorbable vascular grafts showed well-organized neointimal formation in the high-pressure arterial circulation environment. The large-pore scaffold did not improve cellular infiltration and neotissue formation compared with the small-pore scaffold.

TGF-β receptor 1 inhibition prevents stenosis of tissue-engineered vascular grafts by reducing host mononuclear phagocyte activation

Stenosis is a critical problem in the long-term efficacy of tissue-engineered vascular grafts (TEVGs). We previously showed that host monocyte infiltration and activation within the graft drives stenosis and that TGF-β receptor 1 (TGF-βR1) inhibition can prevent it, but the latter effect was attributed primarily to inhibition of mesenchymal cell expansion. In this study, we assessed the effects of TGF-βR1 inhibition on the host monocytes. Biodegradable TEVGs were implanted as inferior vena cava interposition conduits in 2 groups of C57BL/6 mice (n = 25/group): unseeded grafts and unseeded grafts with TGF-βR1 inhibitor systemic treatment for the first 2 wk. The TGF-βR1 inhibitor treatment effectively improved TEVG patency at 6 mo compared to the untreated control group (91.7 vs. 48%, P < 0.001), which is associated with a reduction in classic activation of mononuclear phagocytes. Consistent with these findings, the addition of rTGF-β to LPS/IFN-γ-stimulated monocytes enhanced secretion of inflammatory cytokines TNF-α, IL-12, and IL-6; this effect was blocked by TGF-βR1 inhibition (P < 0.0001). These findings suggest that the TGF-β signaling pathway contributes to TEVG stenosis by inducing classic activation of host monocytes. Furthermore, blocking monocyte activation by TGF-βR1 inhibition provides a viable strategy for preventing TEVG stenosis while maintaining neotissue formation.-Lee, Y.-U., de Dios Ruiz-Rosado, J., Mahler, N., Best, C. A., Tara, S., Yi, T., Shoji, T., Sugiura, T., Lee, A. Y., Robledo-Avila, F., Hibino, N., Pober, J. S., Shinoka, T., Partida-Sanchez, S., Breuer, C. K. TGF-β receptor 1 inhibition prevents stenosis of tissue-engineered vascular grafts by reducing host mononuclear phagocyte activation.

Rational design of an improved tissue-engineered vascular graft: determining the optimal cell dose and incubation time

AIM

We investigated the effect of cell seeding dose and incubation time on tissue-engineered vascular graft (TEVG) patency.

MATERIALS & METHODS

Various doses of bone marrow-derived mononuclear cells (BM-MNCs) were seeded onto TEVGs, incubated for 0 or 12 h, and implanted in C57BL/6 mice. Different doses of human BM-MNCs were seeded onto TEVGs and measured for cell attachment.

RESULTS

The incubation time showed no significant effect on TEVG patency. However, TEVG patency was significantly increased in a dose-dependent manner. In the human graft, more bone marrow used for seeding resulted in increased cell attachment in a dose-dependent manner.

CONCLUSION

Increasing the BM-MNC dose and reducing incubation time is a viable strategy for improving the performance and utility of the graft.

Imaging Angiogenesis Using 99mTc-Macroaggregated Albumin Scintigraphy in Patients with Peripheral Artery Disease

One problem of vascular angiogenesis therapy is the lack of reliable methods for evaluating blood flow in the microcirculation. We aimed to assess whether (99m)Tc-macroaggregated albumin perfusion scintigraphy ((99m)Tc-MAA) predicts quantitated blood flow after therapeutic angiogenesis in patients with peripheral artery disease.

METHODS

Forty-six patients with peripheral artery disease were treated with bone marrow mononuclear cell implantation (BMCI). Before and 4 wk after BMCI, blood flow was evaluated via transcutaneous oxygen tension (TcPO2), ankle-brachial index, intravenous (99m)Tc-tetrofosmin perfusion scintigraphy ((99m)Tc-TF), and intraaortic (99m)Tc-MAA.

RESULTS

Four weeks after BMCI, TcPO2 improved significantly (20.4 ± 14.4 to 36.0 ± 20.0 mm Hg, P < 0.01), but ankle-brachial index did not (0.65 ± 0.30 to 0.76 ± 0.24, P = 0.07). Improvement in (99m)Tc-TF count (0.60 ± 0.23 to 0.77 ± 0.29 count ratio/pixel, P < 0.01) and (99m)Tc-MAA count (5.21 ± 3.56 to 10.33 ± 7.18 count ratio/pixel, P = 0.02) was observed in the foot region but not the lower limb region, using both methods. When these data were normalized by subtracting the pixel count of the untreated side, the improvements in (99m)Tc-TF count (-0.04 ± 0.26 to 0.08 ± 0.32 count ratio/pixel, P = 0.04) and (99m)Tc-MAA count (1.49 ± 3.64 to 5.59 ± 4.84 count ratio/pixel, P = 0.03) in the foot remained significant. (99m)Tc-MAA indicated that the newly developed arteries were approximately 25 μm in diameter.

CONCLUSION

BMCI induced angiogenesis in the foot, which was detected using (99m)Tc-TF and (99m)Tc-MAA. (99m)Tc-MAA is a useful method to quantitate blood flow, estimate vascular size, and evaluate flow distribution after therapeutic angiogenesis.

A mouse model of endocardial fibroelastosis

BACKGROUND

Endocardial fibroelastosis (EFE) is a pathologic condition of abnormal deposition of collagen and elastin within the endocardium of the heart. It is seen in conjunction with a variety of diseases including hypoplastic left heart syndrome and viral endocarditis. While an experimental model using heterotopic heart transplant in rats has been described, we sought to fully describe a mouse model that can be used to further elucidate the potential mechanisms of and treatments for EFE.

MATERIALS AND METHODS

The hearts of 2-day-old C57BL/6 mice were transplanted into the abdomen of 7-week-old C57BL/6 mice. At 2 weeks, the hearts were harvested and histologic analysis was performed using hematoxylin and eosin, Masson's trichrome, Russell-Movat's pentachrome, Picrosirius red, Hart's, Verhoeff-Van Gieson, and Weigert's Resorcin-Fuchsin stains. Additionally, one heart was analyzed using transmission electron microscopy (TEM).

RESULTS

Specimens demonstrated abnormal accumulation of both collagen and elastin within the endocardium with occasional expansion into the myocardium. Heterogeneity in extracellular matrix deposition was noted in the histologic specimens. In addition, TEM demonstrated the presence of excess collagen within the endocardium.

CONCLUSIONS

The heterotopic transplantation of an immature heart into a mouse results in changes consistent with EFE. This model is appropriate to investigate the etiology and treatment of EFE.