Molecular mechanisms of postoperative atrial fibrillation in patients with obstructive sleep apnea.

Obstructive sleep apnea (OSA) promotes atrial remodeling and fibrosis, providing a substrate for atrial fibrillation (AF). Herein, we investigate the pathophysiological mechanisms of AF in association with OSA in a cohort of cardiac surgery patients. A prospective study including patients undergoing cardiac surgery. Biomarkers reflective of AF pathophysiology (interleukin [IL-6], C-reactive protein [CRP], von Willebrand factor [vWF], N-terminal pro-brain natriuretic peptide [NT-proBNP], high-sensitivity Troponin T [hs-TnT], and Galectin-3 [Gal-3]) was assessed by functional or immunological assays. miRNAs involved in AF were analyzed by reverse transcription-polymerase chain reaction (RT-PCR). Using atrial tissue samples, fibrosis was assessed by Masson's trichrome. Connexin 40 and 43 (Cx40; Cx43) were evaluated by immunolabeling. Fifty-six patients (15 with OSA and 41 non-OSA) were included in this hypothesis-generating pilot study. OSA group had a higher incidence of postoperative AF (POAF) (46.7% vs. 19.5%; p = .042), presented an increased risk of POAF (OR 3.61, 95% CI 1.01-12.92), and had significantly higher baseline levels of NT-proBNP (p = .044), vWF (p = .049), Gal-3 (p = .009), IL-6 (p = .002), and CRP (p = .003). This group presented lower levels of miR-21 and miR-208 (both p < .05). Also, lower Cx40 levels in POAF and/or OSA patients (50.0% vs. 81.8%, p = .033) were found. The presence of interstitial fibrosis (according to myocardial collagen by Masson's trichrome) was raised in OSA patients (86.7% vs. 53.7%, p = .024). Several biomarkers and miRNAs involved in inflammation and fibrosis were dysregulated in OSA patients, which together with a higher degree of interstitial fibrosis, altered miRNA, and Cxs expression predisposes to the development of a substrate that increases the AF risk.

Inhibition of enzymes involved in collagen cross-linking reduces vascular smooth muscle cell calcification.

Vascular smooth muscle cells (VSMCs) transdifferentiate into osteoblast-like cells during vascular calcification, inducing active remodeling and calcification of the extracellular matrix (ECM). Intracellular and extracellular enzymes, such as lysyl hydroxylase 1 (PLOD1) and lysyl oxidase (LOX), contribute to ECM maturation and stabilization. We assessed the contribution of these enzymes to hyperphosphatemia-induced calcification. Human and murine VSMCs were differentiated into functional osteoblast-like cells by high-phosphate medium (HPM) conditioning. HPM promoted ECM calcification and up-regulated osteoblast markers associated with induction of LOX and PLOD1 expression and with an increase in ECM-insoluble collagen deposition. Murine VSMCs from transgenic mice overexpressing LOX (TgLOX) exhibited an increase in HPM-dependent calcification and osteoblast commitment compared with wild-type cells. Similarly, enhanced HPM-induced calcification was detected in aorta from TgLOX. Conversely, ß-aminopropionitrile (a LOX inhibitor) and LOX knockdown abrogated VSMC calcification and transdifferentiation. We found a significant positive association between LOX expression and vascular calcification in human atherosclerotic lesions. Likewise, 2,2'-dipyridil (a PLOD inhibitor) and PLOD1 knockdown impaired HPM-induced ECM mineralization and osteoblast commitment. Our findings identify LOX and PLOD as critical players in vascular calcification and highlight the importance of ECM remodeling in this process.-Jover, E., Silvente, A., Marín, F., Martínez-González, J., Orriols, M., Martinez, C. M., Puche, C. M., Valdés, M., Rodriguez, C., Hernández-Romero, D. Inhibition of enzymes involved in collagen cross-linking reduces vascular smooth muscle cell calcification.

Combined determination of B-type natriuretic peptide and high-sensitivity troponin I in the postmortem diagnosis of cardiac disease.

Cardiac disease is the most common cause of sudden death in Western countries. It is known that high-sensitivity troponin I (hs-cTnI), widely used for detection of myocardial injury, is a sensitive biochemical marker. B-type natriuretic peptide (BNP) is a reliable tool for diagnosing heart failure, and for establishing prognosis or disease severity. We aimed to evaluate the diagnostic efficacy of the postmortem determination of BNP in serum alone or in addition to other biomarkers, such as hs-cTnI and MB isoenzyme of creatine kinase (CK-MB), to ascertain whether its determination improves the post-mortem diagnosis of heart failure-associated causes of death. This study involved 133 cadavers with a mean age of 58.2 (± 17.6) years and a mean postmortem interval of 12.8 (±6.6) h. Cases were assigned into two diagnostic groups, according to the cause of death: cardiac deaths (N = 62) and control (N = 71). In the cardiac group, two categories were established according to morphological features of the heart: 'ischemic deaths' (N = 39), and 'congestive heart' (n = 23). Both hs-cTnI and BNP were useful in diagnosing cardiac deaths, whereas CK-MB did not have any diagnostic relevance. hs-cTnI is higher in cases which acute ischemia as the principal pathology, while the presence of high BNP values is significantly related with chronic cardiac situations with significant ventricular overload. Our findings show that postmortem determination of hs-cTnI and BNP provides valuable information; hs-cTnI is useful for diagnosis of cardiac deaths, mainly with ischemic implications, and BNP gave better results for the diagnosis of congestive heart failure.

Clinical implications of nonsarcomeric gene polymorphisms in hypertrophic cardiomyopathy.

BACKGROUND: Hypertrophic cardiomyopathy (HCM) is characterized by cardiomyocyte hypertrophy and fibrosis. Although is an autosomal dominant trait, a group of nonsarcomeric genes have been postulated as modifiers of the phenotypic heterogeneity. MATERIAL AND METHODS: We prospectively recruited 168 HCM patients and 136 healthy controls from three referral centres. Patients and controls were clinically stable at entry in the study. Nine polymorphisms previously associated with ventricular remodelling were determined: I/D ACE, AGTR1(A1666C), CYP11B2(C344T), PGC1-α(G482S), COLIA1(G2046T), ADRB1(R389G), NOS3(G894T), RETN(-420C>G) and CALM3(-34T>A). Their potential influence on prognosis, assessed by hospital admissions, and their cause were recorded. RESULTS: The median follow-up time was 49·5 months. Allele and genotype frequencies did not differ between patients and controls. Thirty-six patients (21·5%) required urgent hospitalization (18·5% for heart failure, 22·2% for atrial arrhythmias, 11·1% for ventricular arrhythmias, 29·6% for ischaemic heart disease, 14·8% for stroke and 3·7% for other reasons) with a hospitalization rate of 8·75% per year. Multivariate analysis showed an independent predictive value for noncarriers of polymorphic COL1A1 allele [HR: 2·76(1·26-6·05), P = 0·011] and a trend in homozygous carriers of ADRB1 Arg389 variant [HR: 1·98(0·99-4·02); P = 0·057]. CONCLUSION: Our study suggests that COL1A1 polymorphism (2046G>T) is an independent predictor of prognosis in HCM patients supporting the importance of nonsarcomeric genes on clinical prognosis in HCM.

Von Willebrand factor is associated with atrial fibrillation development in ischaemic patients after cardiac surgery.

AIMS: Atrial fibrillation (AF) is associated with an increased morbidity and mortality after cardiac surgery. Von Willebrand factor (vWF) has been proposed as a biomarker of endothelial damage/dysfunction. We hypothesized that vWF levels could be used as valuable biomarker for AF occurrence after cardiac surgery. Moreover, we explored the potential association between vWF and tissue remodelling as possible implication in post-surgical AF. METHODS AND RESULTS: We prospectively recruited 100 consecutive patients who undergoing programmed cardiac surgery with cardiopulmonary bypass and with no previous history of AF. Plasma vWF levels were determined from citrated plasma samples. Right atrial appendage tissue was obtained during cardiac surgery, and vWF expression as well as interstitial fibrosis was analysed by immunostaining and Masson's trichrome, respectively. We found raised vWF plasma levels in ischaemic vs. valvular patients (200.2 ± 66.3 vs. 157.2 ± 84.3 IU/dL; P = 0.015). Fibrosis degree was associated with plasma vWF levels. Plasma vWF was an independent prognostic marker for AF development in ischaemic patients [odds ratio, OR 6.44 (95% confidence interval, CI 1.40-36.57), P = 0.035]. CONCLUSION: Plasma vWF levels are associated with tissue fibrosis in patients undergoing cardiac surgery and with post-surgical AF development in ischaemic patients. These findings suggest an association among vWF levels, atrial remodelling, and AF development. It is supported by higher vWF expression in right atrial tissue in ischaemic patients, who developed post-surgical AF.

Long-Term Predictors of Thromboembolic Events in Nonvalvular Atrial Fibrillation Patients Undergoing Electrical Cardioversion.

BACKGROUND: Patients with nonvalvular atrial fibrillation (AF) who undergo electrical cardioversion (ECV) tend to be younger and have less comorbidity. Long-term anticoagulation after ECV should be based on thromboembolic risk. We sought to study the long-term incidence of thromboembolic events (TE), factors related to TE and compare the predictive value of the CHADS2and CHA2DS2-VASc scores in this particular population. METHODS AND RESULTS: From January 2008 to June 2012, 571 ECV were performed in 406 consecutive patients with nonvalvular AF. Risk factors for TE and factors related to anticoagulation therapy after ECV were registered. During a follow-up of approximately 2 years, the annual incidence of TE was 1.9%. Factors associated with TE were: poor quality anticoagulation control (hazard ratio [HR]: 2.91; 95% confidence interval [CI]: 1.10-7.80; P=0.03), cessation of anticoagulation after ECV (HR: 8.80; 95% CI: 3.11-25.10; P<0.001), age ≥65 years (HR: 13.65; 95% CI: 1.74-107.16; P=0.01), CHADS2score (HR: 1.59; 95% CI: 1.10-2.29; P=0.01) and CHA2DS2-VASc score (HR: 1.67; 95% CI: 1.30-2.22; P<0.001). Both risk scores predicted TE [c-statistic for CHADS2: 0.68 (95% CI: 0.62-0.74; P=0.005), for CHA2DS2-VASc: 0.75 (95% CI: 0.70-0.80; P<0.001)]. Based on c-statistics, the predictive accuracy of CHA2DS2-VASc was superior (difference between areas: 0.064±0.031; P=0.0403). CONCLUSIONS: Important determinants of long-term occurrence of TE after ECV were related to anticoagulant therapy (poor quality anticoagulation and cessation of this therapy over follow-up). The CHA2DS2-VASc score successfully predicts TE after ECV, having better predictive accuracy than the CHADS2score. (Circ J 2016; 80: 605-612).

Platelet reactivity over time in coronary artery disease patients treated with a bioabsorbable everolimus-eluting scaffold.

Everolimus-eluting bioabsorbable scaffolds (BVSs) have exhibited similar long-term clinical outcomes compared to its everolimus-eluting metallic counterparts. However, reports from earlier studies have shown a signal for an increased rate of stent thrombosis. The aim of the current investigation is to describe the platelet reactivity profiles over time in patients treated with everolimus-eluting BVS in comparison to everolimus-eluting metallic stents. This is a pilot study in which patients on aspirin and clopidogrel with at least 1 everolimus-eluting BVS were included (n = 24). Patients with at least 1 everolimus-eluting metallic stent implanted were included as control group (n = 25). Blood samples were taken at time of discharge and at 3- and 6-month follow-up. Platelet function tests included VerifyNow (VN-P2Y12), multiplate aggregometry (MEA), and light transmission aggregometry (LTA). There was no difference in platelet reactivity at discharge, 3- and 6-month visits (unadjusted p = 0.733 and p = 0.582; p = 0.432 and p = 0.899 after adjusting for discharge value platelet reactivity0, respectively) using VN-P2Y12. Similar findings were observed with LTA. However, patients with BVS showed significantly higher platelet reactivity than patients with metallic stents at 3 and 6 months in the crude analysis (p = 0.003) and after adjusting for discharge value (p = 0.013) measured with ADP-MEA. There were no differences in platelet reactivity mediated by the T × A2 pathway between both groups. Finally, there is no statistical difference in high on-clopidogrel platelet reactivity (HPR) rate between both groups. The results of this pilot study suggest that BVS might have different platelet reactivity profiles, and warrants further investigation in dedicated clinical studies.

New Approaches to the Role of Thrombin in Acute Coronary Syndromes: Quo Vadis Bivalirudin, a Direct Thrombin Inhibitor?

The pathophysiology of acute coronary syndrome (ACS) involves platelet activation and thrombus formation after the rupture of atherosclerotic plaques. Thrombin is generated at the blood-plaque interface in association with cellular membranes on cells and platelets. Thrombin also amplifies the response to the tissue injury, coagulation and platelet response, so the treatment of ACS is based on the combined use of both antiplatelet (such as aspirin, clopidogrel, prasugrel and ticagrelor) and antithrombotic drugs (unfractionated heparin, enoxaparin, fondaparinux and bivalirudin). Bivalirudin competitively inhibits thrombin with high affinity, a predictable response from its linear pharmacokinetics and short action. However, a present remarkable controversy exists between the latest main Guidelines in Clinical Practice and the key trials evaluating the use of bivalirudin in ACS. The aim of this review is to update the development of bivalirudin, including pharmacological properties, obtained information from clinical trials evaluating efficacy and safety of bivalirudin in ACS; as well as the recommendations of clinical Guidelines.

CALU polymorphism A29809G affects calumenin availability involving vascular calcification.

Calumenin inhibits gamma-carboxylation of matrix-Gla-protein preventing BMP2-dependent calcification. Our aim was to explore the clinical relevance and functionality of the CALU polymorphism rs1043550, and the relationship of calumenin time-dependent expression profile with the active calcification of human vascular smooth muscle cells (hVSMC). Coronary artery calcium score and lesion severity were assessed by cardiac computed tomography in 139 consecutive low-risk patients genotyped for rs1043550. Polymorphic (G) allele carriage was associated with lower calcium (OR: 6.19, p=0.042). Calcified arteries from CALU 'A' allele carriers undergoing cardiovascular surgery exhibited higher residual calcification, higher calumenin immunostaining and lower matrix-Gla-protein, contrary to 'G' allele carriers. In a luciferase reporter system in vascular cells, polymorphic 'G' allele reduced the mRNA stability by 30% (p < 0.05). Osteogenic high-phosphate media induced active differentiation of hVSMC onto functional osteoblast-like cells as demonstrated by extracellular matrix mineralization and osteoblast markers expression. Calumenin was early over-expressed at day 3 (p < 0.05), but decreased thereafter (mRNA and protein) with implications on gamma-carboxylation system. Calumenin was found released and co-localizing with extracellular matrix calcifications. The CALU polymorphism rs1043550 affects mRNA stability and tissue availability of calumenin thus supporting the protective clinical significance. Calumenin shows a time-dependent profile during induced calcification. These data demonstrate a novel association of vascular calcification with the VSMC phenotypic transition into osteoblast-like cells. Moreover, hyperphosphatemic stimuli render calumenin accumulation in the mineralized extracellular matrix.

TWEAK and NT-proBNP levels predict exercise capacity in hypertrophic cardiomyopathy.

BACKGROUND: Hypertrophic cardiomyopathy (HCM) is characterized by inappropriate hypertrophy, myocyte disarray and increased interstitial fibrosis. The tumour necrosis factor-like weak inducer of apoptosis (TWEAK) is a cell surface cytokine with biological activities including stimulation of cell growth, induction of inflammatory cytokines and stimulation of apoptosis. There are controversial data about the potential role of TWEAK in different cardiovascular pathologies. NT-proBNP is an established biomarker of myocardial wall stress, associated with poor functional class in HCM. We hypothesized that effort capacity in patients with HCM could be related to serum levels of these biomarkers. MATERIALS AND METHODS: We included 40 haemodynamic stable HCM patients and 53 healthy controls with similar sex and age. We studied exercise capacity by maximal oxygen consumption in a limited treadmill exercise test. TWEAK and NT-proBNP were assayed by ELISA method and automated Elecsys® platform, respectively. We obtained 46 samples of myocardial tissues by septal myectomy in patients with HCM and evaluated myocardial fibrosis, immunoreaction with TWEAK antibody and apoptosis with TUNEL assay. RESULTS: We found raised TWEAK and NT-proBNP serum levels in patients when compared with control levels (both P < 0.001). In a multivariate analysis, TWEAK and NT-proBNP levels, as well as sex, remained independently associated with the effort capacity (all P < 0.05). We found an association between immunoreaction degree and the degree of myocardial fibrosis (P = 0.021), as well as apoptosis (P = 0.002) in the tissue samples from patients undergoing septal myectomy. CONCLUSIONS: TWEAK and NT-proBNP levels are biomarkers of disease severity independently associated with the effort capacity in patients with HCM.

Small-size platelet microparticles trigger platelet and monocyte functionality and modulate thrombogenesis via P-selectin.

This study aimed to examine the mechanisms of cellular activation by small-size platelet microparticles (sPMP) and to present the performance of high-resolution flow cytometry for the analysis of subcellular entities from different origins. Plasma counts of sPMP were analysed in coronary artery disease patients (n = 40) and healthy controls (n = 40). The effect of sPMP and platelet debris (PD) in pathophysiologically relevant doses on platelet and monocyte activation parameters and thrombogenesis was investigated via flow cytometry and thromboelastometry. New generation flow cytometry identifies differences in size, levels and surface molecules of sPMP derived in the absence of stimulus, thrombin activation and platelet disruption. Addition of sPMP resulted in platelet degranulation and P-selectin redistribution to the membrane (P = 0·019) in a dose and time-dependent manner. Blood clotting time decreased after addition of sPMP (P = 0·005), but was not affected by PD. Blocking P-selectin (CD62P) in sPMP markedly reverted the effect on thrombus kinetics (P = 0·035). Exposure to sPMP stimulated monocyte expression of intercellular adhesion molecule-1 (P < 0·03) and decreased monocyte interleukin-6 receptor density (P < 0·01). These results implicate sPMP as a direct source of downstream platelet and monocyte activation. In pathological coronary artery disease conditions, higher levels of sPMP favour a prothrombotic state, partly through P-selectin expression.

The prognostic role of the adiponectin levels in atrial fibrillation.

BACKGROUND: Patients with atrial fibrillation (AF) have a high morbidity and mortality from vascular events, even despite oral anticoagulation (OAC). Rather than being a risk factor, AF has been proposed as a risk marker, being a signal of advanced atherosclerosis. Circulating adiponectin levels, a cytokine with anti-inflammatory and cardioprotector roles, are related to different atherosclerotic risk factors. The aim is to evaluate whether plasma adiponectin can be predictive of cardiovascular risk in anticoagulated patients with AF. MATERIALS AND METHODS: We included 918 stable anticoagulated out patients with nonvalvular AF [50·1% male; median age 76 (70-80) years; median score for the stroke risk stratification scheme CHA(2) DS(2) -VASc was 4 (3-5)]. Plasma adiponectin was determined by ELISA. Clinical follow-up and cardiovascular adverse events were recorded. RESULTS: After a median follow-up of 956 (784-1085) days, 113 cardiovascular events were recorded (annual rate 4·70%/year) and 99 patients died (rate 4·12%/year). Low plasma adiponectin (< 4444 ng/mL) was significantly associated with major cardiovascular events in female patients [HR 2·96 (95%CI 1·78-4·92)]; P < 0·001, even after adjusting for clinical confounder factors. Adiponectin was neither predictive of stroke/thromboembolism nor all-cause mortality in females, nor for any end-point in males. CONCLUSIONS: Adiponectin is suggested as an independent prognostic biomarker for cardiovascular events in anticoagulated female patients with AF. Our data reinforce the importance of AF as a risk marker of atherosclerotic vascular damage.

Comparative determination and monitoring of biomarkers of necrosis and myocardial remodeling between radiofrequency ablation and cryoablation.

BACKGROUND: Biomarkers of necrosis and inflammation have been found raised after radiofrequency ablation (RF). There is scarce information on biomarkers' behavior after cryoablation. Our aim was to study biomarkers of necrosis, inflammation, and interstitial remodeling after two different approaches: RF versus cryoablation. METHODS: We studied 22 consecutive patients with atrial flutter who underwent RF (10) or cryoablation (12). All patients underwent electrophysiological study and subsequent ablation. Peripheral samples were collected before the procedure, immediately after, the following day, 3 days, 1 week, 1 month, and 2 months after ablation. Samples were assayed for biomarkers of inflammation (high sensitive C-reactive protein [hs-CRP]) and tissue remodeling (C-propeptide of type I procollagen [CICP], matrix metalloproteinase 2 [MMP-2], matrix metalloproteinase 9 [MMP-9], and metallopeptidase inhibitor 1 [TIMP-1]). We also determined biomarkers of tissue necrosis (creatine kinase [CK], its MB isoenzyme, cardiac troponin I [TnI], and troponin T (TnT)] in samples obtained immediately after ablation, 6 hours postablation, and 12 hours postablation. RESULTS: Bidirectional isthmus block was achieved in all patients. We found significantly higher levels of CK, CK-MB, and TnI after cryoablation compared to RF ablation for all timing samples. These necrosis biomarkers showed significant differences depending on the time (all P < 0.001), and the interaction between the time and the used ablation approach (P = 0.005, P < 0.001, and P < 0.001, respectively). For patients who undergoing RF ablation, MMP-2 showed the greatest changes depending on the interaction between time and number of applications (P = 0.041), whereas for patients who undergoing cryoablation, CK was the most relevant biomarker depending on the interaction between time and number of applications (P = 0.006). CONCLUSIONS: We show higher levels of necrosis and myocardial injury biomarker after cryoablation versus RF. However, we found higher remodeling processes after RF. Our data support previous publications showing different lesion formation in cryoablation and RF.

High-sensitivity troponin T and copeptin in non-ST acute coronary syndromes: implications for prognosis and role of hsTnT and copeptin in non-STEACS.

UNLABELLED: High-sensitivity TnT (hsTnT) has been proposed to improve the diagnosis and stratification in acute coronary syndromes. Copeptin has been proposed for a rapid and accurate rule out of acute myocardial infarction, but some doubts exist about its use out of the first hours from admission. Abnormalities of serum hsTnT and copeptin levels in non-STEACS and negative TnT, could have prognostic implications. METHODS: We included 122 non-STEACS patients without raised TnT, 33 disease controls and 43 healthy controls. We measured hsTnT and copeptin levels. Clinical follow-up at 12 months was performed for adverse endpoints. RESULTS: Non-STEACS patients had raised hsTnT compared with both control groups (P = 0.036 and P < 0.001). Copeptin levels were higher in non-STEACS patients than healthy controls (P = 0.021), without differences with disease controls. Raised levels of hs-TnT presented prognostic implications [HR 3.29 (95%CI: 1.33-7.49), P = 0.010]. hs-TnT could be used for invasive approach decision, as it shows prognostic relevance in conservative approach-patients whereas remains unrelevant for catheterized-patients. Copeptin levels were not associated with adverse events. CONCLUSION: hsTnT levels increased in non-STEACS, were predictive of adverse events and could be important for recommending an invasive management. We cannot confirm a predictive role of copeptin out of the first hours from admission.

Whole organ, venation and epidermal cell morphological variations are correlated in the leaves of Arabidopsis mutants.

Despite the large number of genes known to affect leaf shape or size, we still have a relatively poor understanding of how leaf morphology is established. For example, little is known about how cell division and cell expansion are controlled and coordinated within a growing leaf to eventually develop into a laminar organ of a definite size. To obtain a global perspective of the cellular basis of variations in leaf morphology at the organ, tissue and cell levels, we studied a collection of 111 non-allelic mutants with abnormally shaped and/or sized leaves, which broadly represent the mutational variations in Arabidopsis thaliana leaf morphology not associated with lethality. We used image-processing techniques on these mutants to quantify morphological parameters running the gamut from the palisade mesophyll and epidermal cells to the venation, whole leaf and rosette levels. We found positive correlations between epidermal cell size and leaf area, which is consistent with long-standing Avery's hypothesis that the epidermis drives leaf growth. In addition, venation parameters were positively correlated with leaf area, suggesting that leaf growth and vein patterning share some genetic controls. Positional cloning of the genes affected by the studied mutations will eventually establish functional links between genotypes, molecular functions, cellular parameters and leaf phenotypes.

Diagnostic Application of Postmortem Cardiac Troponin I Pericardial Fluid/Serum Ratio in Sudden Cardiac Death.

In approximately 5% of unexpected deaths, establishing a conclusive diagnosis exclusively on the basis of anatomo-pathological findings in a classic autopsy is difficult. Postmortem biomarkers have been actively investigated as complementary indicators to help to reach valid conclusions about the circumstances of death. Several studies propose either the pericardial fluid or peripheral veins as a location for troponin determination, but the optimum sampling site is still a matter of debate. Our objective was to evaluate the association between the ratio of troponin values in the pericardial fluid and serum (determined postmortem) and the diagnosis of acute myocardial infarction (AMI) in the context of sudden cardiac death. We included 175 forensic cases. Two groups were established: AMI deaths (48; 27.4%) and the control group (127; 72.6%). The cardiac Troponin I (cTnI) values in the pericardial fluid and the troponin ratio were found to be associated with the cause of death. Univariate regression analyses showed that both age and the cTnI ratio were significantly associated with the diagnosis of AMI death. In a multivariate analysis, adjusting for confounding factors, the age and cTnI ratio were independent predictors of death from myocardial infarction. We performed a receiver operating characteristic (ROC) curve for the cTnI ratio for AMI death and selected a cut-off point. Our biomarker was found to be a valuable and highly effective tool for use in the forensic field as a complementary method to facilitate diagnosis in nonconclusive autopsies.

Serum levels of high-sensitivity troponin T: a novel marker for cardiac remodeling in hypertrophic cardiomyopathy.

BACKGROUND: Hypertrophic cardiomyopathy (HCM) is characterized by inappropriate hypertrophy, small-vessel coronary artery disease, myocyte disarray, and increased interstitial fibrosis. High-sensitivity troponin T (hs-TnT) could be a reliable indicator of myocardial remodeling, a proposed prognostic marker in HCM. Therefore we hypothesized that increased hs-TnT levels are related to different variables associated with myocardial remodeling, such as the presence of fibrosis assessed with cardiac magnetic resonance imaging (MRI). METHODS AND RESULTS: We included 95 hemodynamically stable HCM patients, 72 male, aged 45.7 ± 14.2 years, and 45 healthy control subjects with similar age and gender. A complete history and clinical examination was performed, including 12-lead electrocardiogram (ECG), echocardiography, 24-hour ECG-Holter monitoring, symptom-limited treadmill exercise test, and late gadolinium enhancement in cardiac MRI. Risk factors for sudden death were evaluated. A blinded cardiac MRI was performed with late gadolinium enhancement study. Serum hs-TnT levels were assayed. A high proportion (42%) of hemodynamically stable patients studied showed increased levels of hs-TnT. The hs-TnT levels were raised in patients with severe dyspnea: New York Heart Association (NYHA) functional class ≥3 (P = .020), outflow obstruction (P = .013), systolic dysfunction (P = .037), abnormal blood pressure response (P = .036), and presence of gadolinium enhancement (P = .021). The hs-TnT levels correlated positively with the maximum left ventricular wall thickness (r = 0.47; P < .001), left atrial diameter (r = 0.36, P = .014), and outflow gradient (r = 0.28; P = .008). CONCLUSIONS: A high proportion of hemodynamically stable patients show increased levels of hs-TnT. We observed that raised hs-TnT serum levels are associated with different conditions related to the severity of the disease.

Biomarkers of pathophysiology in hypertrophic cardiomyopathy: implications for clinical management and prognosis.

The study of biomarkers and their signalling pathways has allowed the development of new therapeutic strategies in a range of disorders. The aim of the present systematic review is to provide an overview of different biomarkers in patients with hypertrophic cardiomyopathy that could give some insight into the pathophysiologic mechanism(s) underlying the typical clinical and histological manifestations of the disease. Several pathophysiological models are presented and discussed, including studies that have investigated these biomarkers for diagnostic and prognostic reasons, in relation to disease progression and/or mortality.

Proteomics in Deaths by Drowning: Diagnostic Efficacy of Apolipoprotein A1 and α-1Antitrypsin, Pilot Study.

Drowning is one of the leading causes of death worldwide. The pathophysiology of drowning is complex and, sometimes, interpretation of the circumstances of death in the autopsy becomes the main source of information in its diagnosis. New advances in medical research, such as proteomics, especially in forensic pathology, are still in the development. We proposed to investigate the application of Mass Spectrometry-based technologies, to identify differentially expressed proteins that may act as potential biomarkers in the postmortem diagnosis of drowning. We performed a pilot proteomic experiment with the inclusion of two drowned and two control forensic cases. After applying restrictive parameters, we identified apolipoprotein A1 (ApoA1) and α-1 antitrypsin as differentially expressed between the two diagnostic groups. A validation experiment, with the determination of both proteins in 25 forensic cases (16 drowned and 9 controls) was performed, and we corroborated ApoA1 higher values in the drowning group, whereas α-1 antitrypsin showed lower levels. After adjusting by confounder factors, both remained as predictive independent factors for diagnosis of drowning (p = 0.010 and p = 0.022, respectively). We constructed ROC curves for biomarkers' levels attending at the origin of death and established an ApoA1 cut-off point of 100 mg/dL. Correct classification based on the diagnosis criteria was reached for 73.9% of the cases in a discriminant analysis. We propose apolipoprotein A1 (with our cutoff value for correct classification) and α-1 antitrypsin as valuable biomarkers of drowning. Our study, based on forensic cases, reveals our proteomic approach as a new complementary tool in the forensic diagnosis of drowning and, perhaps, in clinical future implications in drowned patients. However, this is a pilot approach, and future studies are necessary to consolidate our promising preliminary data.

Galectin-3 and ß-trace protein concentrations are higher in clinically unaffected patients with Fabry disease.

Current therapies have not shown benefit in organ damage reversal in Fabry disease (FD), but biomarkers could help risk stratification and prognosis. We investigated if several biomarkers of cardiac fibrosis, cardiac wall stress, myocardial injury, renal function and inflammation, are associated with early cardiac affectation in FD patients. We included FD patients from four cardiology outpatient clinics of southeastern Spain. At inclusion, Galectin-3 (Gal-3), N-terminal proB-type natriuretic peptide, high sensitivity troponin T (hsTnT), ß-trace protein (BTP) and interleukin-6 concentrations were measured. The relation of biomarkers concentrations with clinical features, cardiac involvement and organ affectation according to the Mainz Severity Score Index (MSSI) was investigated. 44 FD patients (n = 21 affected and n = 23 unaffected) were compared to age and sex-respectively matched healthy controls. Significant differences in biomarkers' concentration between FD groups were observed. Importantly, Gal-3 and BTP levels were higher in unaffected patients when compared with age and sex-matched healthy controls (both p < 0.05). All the biomarkers correlated with clinical features. When cut-off values for clinical affectation (measured as MSSI ≥ 20) were established, only hsTnT (OR 30.69, 95% CI 2.70-348.42) and male sex (OR 8.17, 95% CI 1.16-57.75) were independently associated with cardiac damage by multivariate regression analysis. Gal-3 and BTP levels are increased in unaffected FD patients compared to healthy controls. This suggests that these biomarkers could be useful for the early detection of cardiac affectation in FD patients. On the other hand, hsTnT and male sex are independent risk factors for established clinical cardiac damage in FD.