Follistatin-like 1 promotes cardiac fibroblast activation and protects the heart from rupture

Follistatin‐like 1 (Fstl1) is a secreted protein that is acutely induced in heart following myocardial infarction (MI). In this study, we investigated cell type‐specific regulation of Fstl1 and its function in a murine model of MI. Fstl1 was robustly expressed in fibroblasts and myofibroblasts in the infarcted area compared to cardiac myocytes. The conditional ablation of Fstl1 in S100a4‐expressing fibroblast lineage cells (Fstl1‐cfKO mice) led to a reduction in injury‐induced Fstl1 expression and increased mortality due to cardiac rupture during the acute phase. Cardiac rupture was associated with a diminished number of myofibroblasts and decreased expression of extracellular matrix proteins. The infarcts of Fstl1‐cfKO mice displayed weaker birefringence, indicative of thin and loosely packed collagen. Mechanistically, the migratory and proliferative capabilities of cardiac fibroblasts were attenuated by endogenous Fstl1 ablation. The activation of cardiac fibroblasts by Fstl1 was mediated by ERK1/2 but not Smad2/3 signaling. This study reveals that Fstl1 is essential for the acute repair of the infarcted myocardium and that stimulation of early fibroblast activation is a novel function of Fstl1.

Inspection of thick welded joints using laser-ultrasonic SAFT

The detection of defects in thick butt joints in the early phase of multi-pass arc welding would be very valuable to reduce cost and time in the necessity of reworking. As a non-contact method, the laser-ultrasonic technique (LUT) has the potential for the automated inspection of welds, ultimately online during manufacturing. In this study, testing has been carried out using LUT combined with the synthetic aperture focusing technique (SAFT) on 25 and 50mm thick butt welded joints of steel both completed and partially welded. EDM slits of 2 or 3mm height were inserted at different depths in the multi-pass welding process to simulate a lack of fusion. Line scans transverse to the weld are performed with the generation and detection laser spots superimposed directly on the surface of the weld bead. A CCD line camera is used to simultaneously acquire the surface profile for correction in the SAFT processing. All artificial defects but also real defects are visualized in the investigated thick butt weld specimens, either completed or partially welded after a given number of passes. The results obtained clearly show the potential of using the LUT with SAFT for the automated inspection of arc welds or hybrid laser-arc welds during manufacturing.

Prognostic significance of endogenous erythropoietin in long-term outcome of patients with acute decompensated heart failure

AIMS

Although previous reports suggest that an elevated endogenous erythropoietin (EPO) level is associated with worse clinical outcomes in chronic heart failure (HF) patients, the prognostic implication of EPO in patients with acute decompensated HF (ADHF) and underlying mechanisms of the high EPO level in severe HF patients who have a poor prognosis remain unclear.

METHODS AND RESULTS

We examined 539 consecutive ADHF patients with EPO measurement on admission from our registry. During a median follow-up period of 329 days, a higher EPO level on admission was independently associated with worse clinical outcomes [hazard ratio (HR) 1.25, 95% confidence interval (CI) 1.06-1.48, P = 0.008], and haemoglobin level was the strongest determinant of EPO level (P < 0.001), whereas estimated glomerular filtration rate (eGFR) was not significant in multivariate regression analysis. In the anaemic subgroup of 318 patients, a higher EPO level than expected on the basis of their haemoglobin level was related to increased adverse events (HR 1.63, 95% CI 1.05-2.49, P = 0.028). Moreover, estimated plasma volume excess rate was positively associated with EPO level (P = 0.003), and anaemic patients with a higher than expected EPO level tended to have a higher estimated plasma volume excess rate and plasma lactate level, and lower systemic oxygen saturation level with the preservation of the reticulocyte production index than those with a lower than expected EPO level.

CONCLUSION

A high EPO level predicts long-term worse clinical outcomes in ADHF patients, independent of anaemia and impaired renal function. Anaemia and hypoxia due to severe congestion may synergistically contribute to a high EPO level in high-risk HF patients.

Usefulness of Percutaneous Transluminal Coronary Balloon Angioplasty for the Left Coronary Artery Stenosis 10 Years More Than After Arterial Switch Operation

Proximal stenosis adjacent to the orifice of one or both coronary arteries may occur after the arterial switch operation (ASO) for d-transposition of the great arteries (d-TGA). Coronary artery stenosis (CAS) often progresses within the first 6 months postoperatively and may result in myocardial ischemia and infarction. Although percutaneous transluminal coronary balloon angioplasty (PCBA) for CAS within 15 months after ASO for d-TGA has been reported, there is no report of PCBA for CAS in the late period after ASO. We present the results of PCBA for CAS of the left coronary artery performed more than 10 years after ASO in an 11-year-old boy and a 14-year-old boy without complication. The stenosis degree improved in both patients from 81 to 45 and 80 to 54 %, respectively. Restenosis did not occur, and the stenosis degree improved to about 25 % late after PCBA. Although the initial effect of PCBA may not be dramatic, it can improve late after PCBA. It was considered that the optimal balloon-reference vessel ratio was about 1.0, to obtain the minimal effective lumen diameter. PCBA for CAS even if performed many years after ASO is feasible without complication. PCBA can also provide delayed improvement late after the procedure.

Effect of Discontinuation of Prednisolone Therapy on Risk of Cardiac Mortality Associated With Worsening Left Ventricular Dysfunction in Cardiac Sarcoidosis

Prednisolone (PSL) therapy is the gold standard treatment in patients with cardiac sarcoidosis (CS). However, clinicians often have difficulty in deciding whether to discontinue PSL therapy in long-term management. Sixty-one consecutive patients with CS were divided into 2 groups based on the discontinuation of PSL during the median follow-up period of 9.9 years. PSL was discontinued in 12 patients because of improvement of clinical findings. There were no significant differences between the 2 groups in age, gender, left ventricular ejection fraction (LVEF), findings of imaging techniques, incidence of fatal arrhythmias and heart failure, and dose of PSL. After discontinuation of PSL, 5 patients had cardiac death, and discontinuation of PSL was significantly associated with higher cardiac mortality compared with continuation (p = 0.035). Although patients with discontinuation had improvement of LVEF after PSL treatment, LVEF decreased after discontinuation of PSL. Furthermore, discontinuation of PSL was associated with greater percent decrease in LVEF compared with continuation (p = 0.037) during the follow-up period. In conclusion, in the long-term management of patients with CS, discontinuation of PSL was associated with poor clinical outcomes and decreased LVEF, suggesting the importance of PSL maintenance therapy.

Early development of acute kidney injury is an independent predictor of in-hospital mortality in patients with acute myocardial infarction

BACKGROUND

Acute kidney injury (AKI) often occurs in patients with acute myocardial infarction (AMI), and is associated with adverse outcomes. However, it remains unclear how timing of AKI affects it. This study assessed impact of timing of AKI on prognosis after AMI.

METHODS

This study consisted of 760 patients with AMI who were admitted within 48h after symptom onset. AKI was diagnosed as increase in creatinine ≥0.3mg/dl or ≥50% within any 48h after admission. Patients were classified into 3 groups according to the occurrence and timing of AKI: no-AKI, early-AKI (within 48h after admission) and late-AKI (>48h). Early-AKI was classified into transient early-AKI, defined as creatinine returning to the level below the criteria of AKI, and persistent early-AKI.

RESULTS

Early-AKI occurred in 64 patients (9%) and late-AKI in 32 patients (4%). Patients with early-AKI had significantly higher mortality (35%) than those with late-AKI (7%, p<0.001) and no-AKI (3%, p<0.001). Multivariate analysis showed early-AKI was an independent predictor of in-hospital mortality (OR: 3.38, 95% CI: 1.30-8.76, p=0.013), but late-AKI was not. Among patients with early-AKI, mortality was significantly higher even if AKI was transient (23%, p<0.001). Patients with persistent early-AKI had the highest mortality (66%, p<0.001).

CONCLUSIONS

Early-AKI was associated with worse outcome. Even if renal function once returned to baseline level, patients with early-AKI tended to be at high risk of mortality.

Prevalence, Clinical Features, and Prognosis of Acute Myocardial Infarction Attributable to Coronary Artery Embolism

BACKGROUND

Coronary artery embolism (CE) is recognized as an important nonatherosclerotic cause of acute myocardial infarction. Its prevalence, clinical features, and prognosis remain insufficiently characterized.

METHODS AND RESULTS

We screened 1776 consecutive patients who presented with de novo acute myocardial infarction between 2001 and 2013. CE was diagnosed based on criteria encompassing histological, angiographic, and other diagnostic imaging findings. The prevalence, clinical characteristics, treatment strategies, in-hospital outcomes, and long-term risk of CE recurrence or major adverse cardiac and cerebrovascular events (cardiac death, fatal arrhythmia, or recurrent thromboembolism) were evaluated. The prevalence of CE was 2.9% (n=52), including 8 (15%) patients with multivessel CE. Atrial fibrillation was the most common cause (n=38, 73%). Only 39% of patients with CE were treated with vitamin K antagonists, and the median international normalized ratio was 1.42 (range, 0.95-1.80). Eighteen of the 30 CE patients with nonvalvular atrial fibrillation had a CHADS2 score of 0 or 1. When those patients were reevaluated using CHA2DS2-VASc, 61% were reassigned to a higher risk category. During a median follow-up of 49 months, CE and thromboembolism recurred in 5 atrial fibrillation patients. The 5-year rate of major adverse cardiac and cerebrovascular events was 27.1%. In the propensity score-matched cohorts (n=45 each), Kaplan-Meier analysis showed a significantly higher incidence of cardiac death in the CE group than in the non-CE group (hazard ratio, 9.29; 95% confidence interval, 1.13-76.5; P<0.001).

CONCLUSIONS

Atrial fibrillation is the most frequent cause of CE. Patients with CE represent a high-risk subgroup of patients with acute myocardial infarction and require close follow-up.

Effect of Corticosteroid Therapy on Long-Term Clinical Outcome and Left Ventricular Function in Patients With Cardiac Sarcoidosis

BACKGROUND

Cardiac involvement is the worst prognostic determinant in patients with sarcoidosis, but the long-term prognostic significance of corticosteroid therapy for cardiac sarcoidosis (CS) remains unclear.

METHODS AND RESULTS

We examined 83 consecutive patients diagnosed with CS. Patients were divided into 2 groups based on the presence or absence of corticosteroid therapy at diagnosis. Patients with corticosteroid therapy had lower age and higher rate of positive findings in the myocardium on gallium scintigraphy (Ga) at diagnosis than those without. LVEF, biomarkers, and use of cardiovascular medication were similar between the 2 groups. During the follow-up (7.6±4.4 years), corticosteroid therapy was associated with fewer long-term adverse events (overall, P=0.005; cardiac death, P=0.92; symptomatic arrhythmias, P=0.89; heart failure admission, P<0.0001) and a greater % increase in LVEF than those without (7.9±36.3% vs. -16.7±34.8%, P=0.03). On Cox proportional hazards modeling, corticosteroid therapy (HR, 0.41; 95% CI: 0.20-0.89) was an independent determinant of long-term adverse event-free survival, but age, sex, LVEF, and Ga findings were not.

CONCLUSIONS

Corticosteroid therapy might have a beneficial effect on long-term clinical outcome in CS patients, particularly by reduction of heart failure admission and retarding the progression of LV systolic dysfunction.

Impact of acute and chronic hyperglycemia on in-hospital outcomes of patients with acute myocardial infarction

This study was undertaken to assess the impact of acute hyperglycemia (acute-HG) and chronic hyperglycemia (chronic-HG) on short-term outcomes in patients with acute myocardial infarction (AMI). This study consisted of 696 patients with AMI. Acute-HG was defined as admission plasma glucose ≥200 mg/dl and chronic-HG as hemoglobin A1c ≥6.5%. Acute-HG was associated with higher peak serum creatine kinase (4,094 ± 4,594 vs 2,526 ± 2,227 IU/L, p <0.001) and in-hospital mortality (9.8% vs 1.6%, p <0.001). On the contrary, there was no significant difference in peak creatine kinase (2,803 ± 2,661 vs 2,940 ± 3,181 IU/L, p = 0.59) and mortality (3.3 vs 3.7%, p = 0.79) between patients with chronic-HG and those without. Multivariate analysis showed that admission plasma glucose was an independent predictor of in-hospital mortality (odds ratio 1.15, 95% confidence interval 1.05 to 1.27, p <0.001), but hemoglobin A1c was not. When only patients with acute-HG were analyzed, chronic-HG was associated with a significantly smaller infarct size (3,221 ± 3,001 vs 5,904 ± 6,473 IU/L, p <0.001) and lower in-hospital mortality (5.5 vs 18.9%, p = 0.01). In conclusion, these results suggested that acute-HG, but not chronic-HG, was associated with adverse short-term outcomes after AMI. Paradoxically, in patients with acute-HG, chronic-HG might abate the adverse effects of acute-HG.

Trends in the clinical and pathological characteristics of cardiac rupture in patients with acute myocardial infarction over 35 years

Background

There is little known about whether the clinical and pathological characteristics and incidence of cardiac rupture (CR) in patients with acute myocardial infarction (AMI) have changed over the years.

Methods and Results

The incidence and clinical characteristics of CR were investigated in patients with AMI, who were divided into 3 cohorts: 1977–1989, 1990–2000, and 2001–2011. Of a total of 5699 patients, 144 were diagnosed with CR and 45 survived. Over the years, the incidence of CR decreased (1977–1989, 3.3%; 1990–2000, 2.8%; 2001–2011, 1.7%; P=0.002) in association with the widespread adoption of reperfusion therapy. The mortality rate of CR decreased (1977–1989, 90%; 1990–2000, 56%; 2001–2011, 50%; P=0.002) in association with an increase in the rate of emergent surgery. In multivariable analysis, first myocardial infarction, anterior infarct, female sex, hypertension, and age >70 years were significant risk factors for CR, whereas impact of hypertension on CR was weaker from 2001 to 2011. Primary percutaneous coronary intervention (PPCI) was a significant protective factor against CR. In 64 autopsy cases with CR, myocardial hemorrhage occurred more frequently in those who underwent PPCI or fibrinolysis than those who did not receive reperfusion therapy (no reperfusion therapy, 18.0%; fibrinolysis, 71.4%; PPCI, 83.3%; P=0.001).

Conclusions

With the development of medical treatment, the incidence and mortality rate of CR have decreased. However, first myocardial infarction, anterior infarct, female sex, and old age remain important risk factors for CR. Adjunctive cardioprotection against reperfusion‐induced myocardial hemorrhage is emerging in the current PPCI era.

Decreased myocardial dendritic cells is associated with impaired reparative fibrosis and development of cardiac rupture after myocardial infarction in humans

Background

Dendritic cells (DC) play pivotal roles in regulating the immune system and inflammatory response. We previously reported DC infiltration in the infarcted heart and its immunoprotective roles in the post‐infarction healing process after experimental myocardial infarction (MI). However, its clinical significance has not been determined.

Methods and Results

The degree of DC infiltration and its correlation with the post‐infarction healing process in the human infarcted heart were investigated in 24 autopsy subjects after ST‐elevation MI. Patients were divided into two groups according to the presence (n=13) or absence (n=11) of cardiac rupture. The numbers of infiltrated DC and macrophages and the extent of fibrosis in the infarcted area were examined. In the rupture group, CD68⁺ macrophage infiltration was increased and CD209⁺ DC, and CD11c⁺ DC infiltration and the extent of reparative fibrosis were decreased compared with the non‐rupture group, under matched baseline characteristics including the time from onset to death and use of revascularization. Furthermore, there was a significant positive correlation between the number of infiltrating CD209⁺ DC, and CD11c⁺ DC and the extent of reparative fibrosis.

Conclusions

Decreased number of DC in human‐infarcted myocardial tissue was associated with increased macrophage infiltration, impaired reparative fibrosis, and the development of cardiac rupture after MI. These findings suggest a protective role of DC in post‐MI inflammation and the subsequent healing process.