B-type natriuretic peptide and wall stress in dilated human heart

The Relationship between Fragmented QRS and Myocardial Injury in Patients with Acute Carbon Monoxide Poisoning

Background and Objectives: Carbon monoxide (CO) intoxication is one of the most common causes of poisoning-related deaths and complications. Myocardial injury is an important complication of CO poisoning. In our study, we aimed to evaluate the relationship between the presence and prevalence of fragmented QRS (fQRS) and myocardial injury in patients with CO intoxication. Materials and Methods: We retrospectively evaluated patients who presented to the emergency department of our tertiary care center with CO intoxication between January 2020 and December 2023. In our study, we performed subgroup analyses according to the presence of myocardial injury and fQRS. We evaluated the parameters and risk factors associated with myocardial injury. Results: Myocardial injury was detected in 44 patients, and fQRS was detected in 38 patients. In the myocardial injury (+) group, the fQRS rate was 38.6%, and the median number of leads with fQRS was 3 (2-6) and was significantly higher than in the myocardial injury (-) group (p < 0.001). We found that carboxyhemoglobin had a significant positive correlation with troponin (p = 0.001) and pro-B-type natriuretic peptide (proBNP) (p = 0.009). As a result of multivariate analysis, we determined that age, creatinine, proBNP, fQRS, and ≥3 leads with fQRS are independent risk factors for myocardial injury. Conclusions: Myocardial injury in CO intoxication patients is associated with proBNP, the presence of fQRS, and the number of leads with fQRS. Age, creatinine level, proBNP, the presence of fQRS, and ≥3 leads with fQRS are independent risk factors for myocardial injury in patients with CO intoxication.

Clinical Assessment of Ventricular Wall Stress in Understanding Compensatory Hypertrophic Response and Maladaptive Ventricular Remodeling

Ventricular wall stress (WS) is an important hemodynamic parameter to represent myocardial oxygen demand and ventricular workload. The normalization of WS is regarded as a physiological feedback signal that regulates the rate and extent of ventricular hypertrophy to maintain myocardial homeostasis. Although hypertrophy is an adaptive response to increased biomechanical stress, persistent hypertrophic stimulation forces the stressed myocardium into a progressive maladaptive process called ventricular remodeling, consisting of ventricular dilatation and dysfunction in conjunction with the development of myocyte hypertrophy, apoptosis, and fibrosis. The critical determinant of this pathological transition is not fully understood, but an energetic mismatch due to uncontrolled WS is thought to be a central mechanism. Despite extensive basic investigations conducted to understand the complex signaling pathways involved in this maladaptive process, clinical diagnostic studies that translate these molecular and cellular changes are relatively limited. Echocardiographic assessment with or without direct measurement of left ventricular pressure used to be a mainstay in estimating ventricular WS in clinical medicine, but in recent years more and more noninvasive applications with magnetic resonance imaging have been studied. In this review article, basic clinical applications of WS assessment are discussed to help understand the progression of ventricular remodeling.

COPD maintenance medication is linked to left atrial size: Results from the COSYCONET cohort

BACKGROUND

Lung function impairment in COPD is known to be related to reductions of left heart size, while short-term interventional trials with bronchodilators showed positive effects on cardiac parameters. We investigated whether COPD maintenance therapy has analogous long-term effects.

METHODS

Pooled data of GOLD grade 1-4 patients from visits 1 and 3 (1.5 y apart) of the COSYCONET cohort were used. Medication was categorized as use of ICS, LABA + ICS, LABA + LAMA and triple therapy (LABA + LAMA + ICS), contrasting "always" versus "never". Echocardiographic parameters comprised left ventricular end-diastolic and -systolic diameter (LVEDD, LVESD), ejection fraction (LVEF) and left atrial diameter (LA). Associations were identified by multiple regression analysis, as well as propensity score analysis.

RESULTS

Overall, 846 patients (mean age 64.5 y; 41% female) were included, 53% using ICS at both visits, 51% LABA + ICS, 56% LABA + LAMA, 40% LABA + LAMA + ICS (triple) therapy. Conversely, 30%, 32%, 28% and 42% had no ICS, LABA + ICS, LABA + LAMA or triple therapy, respectively, at both visits. Among echocardiographic measures, only LA showed statistically significant associations (increases) with medication, whereby significant effects were linked to ICS, LABA + ICS and LABA + LAMA (p < 0.05 each, "always" versus "never") and propensity score analyses underlined the role of LABA + LAMA.

CONCLUSIONS

In this observational study, COPD maintenance therapy, especially LABA + LAMA, was linked to left atrial size, consistent with the results of short-term interventional trials. These findings suggest that maintenance medication for COPD does not only improve lung function and patient reported outcomes but may also have an impact on the cardiovascular system.

TRIAL REGISTRATION

NCT01245933.

The contribution of cardiac and extracardiac factors to NT-proBNP concentrations in patients with advanced heart failure before and after left ventricular assist device implantation

The clinical significance of N-terminal pro-brain natriuretic peptide (NT-proBNP) in patients undergoing left ventricular assist device (LVAD) implantation is not fully explored. NT-proBNP concentrations are influenced by body composition, renal function and intracardiac pressures; dynamic measures pre- and post-LVAD implantation. We sought to identify the individual contribution of cardiac and extracardiac factors to NT-proBNP concentrations in advanced heart failure patients before and after LVAD implantation. We retrospectively collected data from 63 patients implanted with a LVAD with NT -proBNP measurements (2006-2019). Hemodynamic measurements were obtained through right heart catheterization (RHC). Univariable linear regression and multivariable stepwise regression models were used to analyze variables associated with NT-proBNP concentrations in the pre- and post-LVAD setting. Paired t-test was performed on a subpopulation of 13 patients with complete data. We found significant differences in all extracardiac (BMI, creatinine, eGFR) and all invasive hemodynamic measurements pre-LVAD compared to post-LVAD. NT-proBNP decreased by 83 %, in the subpopulation of 13 patients: 736 pmol/L [IQR 498-1330] to 126 pmol/L [IQR 74.8-241.7]. In multivariable analysis, only creatinine remained significantly associated with NT-proBNP before LVAD implant (p = 0.016), whereas pulmonary capillary wedge pressure (PCWP) was the only independent variable associated with NT-proBNP after LVAD implant (p < 0.0001). Creatinine and PCWP were the only independent factors associated with NT-proBNP concentrations before and after LVAD implantation, respectively. Invasive hemodynamic measurements were more closely associated with NT-proBNP concentration after LVAD than extracardiac factors and reversely pre-LVAD, suggesting that NT-proBNP serves as a useful biomarker of cardiac conditions post-LVAD implantation.

Effect of growth hormone treatment on circulating levels of NT-proBNP in patients with ischemic heart failure

AIMS

Growth hormone (GH) therapy in heart failure (HF) is controversial. We investigated the cardiovascular effects of GH in patients with chronic HF due to ischemic heart disease.

METHODS

In a double-blind, placebo-controlled trial, we randomly assigned 37 patients (mean age 66 years; 95% male) with ischemic HF (ejection fraction [EF] < 40%) to a 9-month treatment with either recombinant human GH (1.4 mg every other day) or placebo, with subsequent 3-month treatment-free follow-up. The primary outcome was change in left ventricular (LV) end-systolic volume measured by cardiac magnetic resonance (CMR). Secondary outcomes comprised changes in cardiac structure and EF. Prespecified tertiary outcomes included changes in New York Heat Association (NYHA) functional class and quality of life (QoL), as well as levels of insulin-like growth factor-1 (IGF-1) and N-terminal pro-brain natriuretic peptide (NT-proBNP).

RESULTS

No changes in cardiac structure or systolic function were identified in either treatment group; nor did GH treatment affect QoL or functional class. In the GH group, circulating levels of IGF-1 doubled from baseline (+105%; p < 0.001) and NT-proBNP levels halved (-48%; p < 0.001) during the treatment period, with subsequently a partial return of both towards baseline levels. No changes in IGF-1 or NT-proBNP were observed in the placebo group at any time during the study.

CONCLUSION

In patients with chronic ischemic HF, nine months of GH treatment was associated with significant increases in levels of IGF-1 and reductions in levels of NT-proBNP, but did not affect cardiac structure, systolic function or functional capacity.

Prognostic value of natriuretic peptides and restrictive filling pattern before surgical ventricular restoration

OBJECTIVE

Both increased natriuretic peptide levels and restrictive filling pattern (RFP) are important risk predictors in patients with heart failure. The aim of this study was to examine the role of the combined use of natriuretic peptide and RFP for the prognostic stratification of patients with ischemic cardiomyopathy undergoing surgical ventricular restoration in the Biomarker Plus study.

METHODS

A total of 186 patients (aged 64 ± 10 years) underwent echocardiographic study and N-terminal pro-B-type natriuretic peptide assay at baseline (before surgical ventricular restoration). Patients were divided into 4 groups depending on baseline diastolic filling pattern (RFP/no RFP) and N-terminal pro-B-type natriuretic peptide level (less than or greater than or equal to the upper tertile value of 2003 ŋg/L). RFP was defined as E/A ratio ≥2. All-cause death or heart failure hospitalizations within 36-month follow-up were analyzed.

RESULTS

Despite similar ejection fraction, volumes, and mass, the 4 groups presented distinct clinical and structural pattern of presurgical ventricular restoration ventricular remodeling and significantly different clinical outcome after surgical unloading. During follow-up, 67 patients died or were hospitalized for heart failure (36%). High N-terminal pro-B-type natriuretic peptide levels and RFP, considered individually, were significantly associated with outcome (P < .0001). The combination of both was associated with the highest adjusted hazard of adverse events (hazard ratio, 3.63; 95% CI, 1.73-7.6; P < .0001).

CONCLUSIONS

The simultaneous use of 2 markers, 1 biological and 1 echocardiographic, may allow better prognostic stratification and characterization of the distinct structural and clinical phenotypes in a population of patients with ischemic cardiomyopathy undergoing surgical ventricular restoration. This approach could be useful in the decision-making process to guide treatment choices in patients with ischemic cardiomyopathy.

Fiber Scaffold Patterning for Mending Hearts: 3D Organization Bringing the Next Step

Heart failure (HF) is a leading cause of death worldwide. The most common conditions that lead to HF are coronary artery disease, myocardial infarction, valve disorders, high blood pressure, and cardiomyopathy. Due to the limited regenerative capacity of the heart, the only curative therapy currently available is heart transplantation. Therefore, there is a great need for the development of novel regenerative strategies to repair the injured myocardium, replace damaged valves, and treat occluded coronary arteries. Recent advances in manufacturing technologies have resulted in the precise fabrication of 3D fiber scaffolds with high architectural control that can support and guide new tissue growth, opening exciting new avenues for repair of the human heart. This review discusses the recent advancements in the novel research field of fiber patterning manufacturing technologies for cardiac tissue engineering (cTE) and to what extent these technologies could meet the requirements of the highly organized and structured cardiac tissues. Additionally, future directions of these novel fiber patterning technologies, designs, and applicability to advance cTE are presented.

Left ventricular volume and wall stress are linked to lung function impairment in COPD

BACKGROUND

Cardiovascular comorbidities are common in chronic obstructive pulmonary disease (COPD). We examined the association between airflow limitation, hyperinflation and the left ventricle (LV).

METHODS

Patients from the COPD cohort COSYCONET underwent evaluations including forced expiratory volume in 1 s (FEV₁), forced vital capacity (FVC), effective airway resistance (R_eff), intrathoracic gas volume (ITGV), and echocardiographic LV end-diastolic volume (LVEDV), stroke volume (LVSV), end-systolic volume (LVESV), and end-diastolic and end-systolic LV wall stress. Data from Visit 1 (baseline) and Visit 3 (18 months later) were used. In addition to comparisons of both visits, multivariate regression analysis was conducted, followed by structural equation modelling (SEM) with latent variables "Lung" and "Left heart".

RESULTS

A total of 641 participants were included in this analysis. From Visit 1 to Visit 3, there were significant declines in FEV₁ and FEV₁/FVC, and increases in R_eff, ITGV and LV end-diastolic wall stress, and a borderline significant decrease in LV mass. There were significant correlations of: FEV₁% predicted with LVEDV and LVSV; R_eff with LVSV; and ITGV with LV mass and LV end-diastolic wall stress. The SEM fitted the data of both visits well (comparative fit index: 0.978, 0.962), with strong correlation between "Lung" and "Left heart".

CONCLUSIONS

We demonstrated a relationship between lung function impairment and LV wall stress in patients with COPD. This supports the hypothesis that LV impairment in COPD could be initiated or promoted, at least partly, by mechanical factors exerted by the lung disorder.

On Materials for Cardiac Tissue Engineering

In this essay the authors argue that chamber pressure dominates the biomechanics of the contraction cycle of the heart, while tissue stiffness dominates the relaxation cycle. This appears to be an under-recognized challenge in cardiac tissue engineering. Optimal approaches will involve constructing chambers or modulating the stiffness of the scaffold/substrate in synchrony with the beating cycle.

Recreating the Cardiac Microenvironment in Pluripotent Stem Cell Models of Human Physiology and Disease

The advent of human pluripotent stem cell (hPSC) biology has opened unprecedented opportunities for the use of tissue engineering to generate human cardiac tissue for in vitro study. Engineering cardiac constructs that recapitulate human development and disease requires faithful recreation of the cardiac niche in vitro. Here we discuss recent progress in translating the in vivo cardiac microenvironment into PSC models of the human heart. We review three key physiologic features required to recreate the cardiac niche and facilitate normal cardiac differentiation and maturation: the biochemical, biophysical, and bioelectrical signaling cues. Finally, we discuss key barriers that must be overcome to fulfill the promise of stem cell biology in preclinical applications and ultimately in clinical practice.

Marine omega-3 highly unsaturated fatty acids: From mechanisms to clinical implications in heart failure and arrhythmias

Therapeutic implications of marine omega-3 highly unsaturated fatty acids (HUFA) in cardiovascular disease are still discussed controversially. Several clinical trials report divergent findings and thus leave ambiguity on the meaning of oral omega-3 therapy. Potential prognostic indications of HUFA treatment have been predominantly studied in coronary artery disease, sudden cardiac death, ventricular arrhythmias, atrial fibrillation and heart failure of various origin. It is suspected that increased ventricular wall stress is crucially involved in the prognosis of heart failure. Increased wall stress and an unfavorable myocardial remodeling is associated with an increased risk of arrhythmias by stretch-activated membrane ion channels. Integration of HUFA into the microenvironment of cardiomyocyte ion channels lead to allosteric changes and increase the electrical stability. Increased ventricular wall stress appears to be involved in the local myocardial as well as in the hepatic fatty acid metabolism, i.e. a cardio-hepatic syndrome. Influences of an altered endogenous HUFA metabolism and an inverse shift of the fatty acid profile was underrated in the past. A better understanding of these interacting endogenous mechanisms appears to be required for interpreting the findings of recent experimental and clinical studies. The present article critically reviews major studies on basic pathophysiological mechanisms and treatment effects in clinical trials.

From Heart Failure to Highly Unsaturated Fatty Acid Deficiency and Vice Versa: Bidirectional Heart and Liver Interactions

BACKGROUND

In several trials, beneficial prognostic effects of highly unsaturated fatty acids (HUFAs) in heart failure were shown. Because other studies showed no incremental benefit in nearly preserved cardiac function, the question arises, whether the degree of cardiac dysfunction is involved. It is hypothesized that increased left ventricular (LV) wall stress affects the endogenous hepatic HUFA metabolism, which in turn exhibits adverse cardiac consequences.

METHODS

Cardiac magnetic resonance imaging was performed in 30 patients with suspected cardiomyopathy. The serum fatty acid profile was assessed using gas chromatography/mass spectrometry.

RESULTS

Docosahexaenoic acid (DHA; P = 0.002) and eicosapentaenoic acid (EPA; by trend) levels were decreased in patients with reduced LV ejection fraction (≤ 50%) or LV dilatation (≥ 90 mL/m(2)). Decreased DHA (P = 0.003) and EPA (P = 0.022) levels were associated with a reduced LV ejection fraction. Decreased DHA level was correlated with increased end-diastolic (P = 0.047) and end-systolic LV wall stress (P = 0.001). Pseudocholinesterase activity was inversely correlated with end-diastolic (P = 0.020) and end-systolic LV wall stress (P = 0.025).

CONCLUSIONS

DHA level was significantly reduced in heart failure. Similar, but less pronounced effects were found for EPA and arachidonic acid by trend. Increased LV wall stress was correlated with a reduced DHA level. Increased LV wall stress exhibits various adverse consequences (eg, increased oxygen consumption, favouring of arrhythmias, and an unfavourable remodelling). The increase of wall stress was paralleled by reduced HUFA level. Increased LV wall stress was correlated with reduced pseudocholinesterase, which is suggestive of hepatic congestion (ie, a cardiohepatic syndrome, involved in the altered fatty acid profile in heart failure) and has major consequences regarding the dose-efficacy of HUFA treatment.

Early trends in N-terminal pro-brain natriuretic peptide values after left ventricular assist device implantation for chronic heart failure

Left ventricular assist devices (LVADs) acutely decrease left ventricular wall stress. Thus, early postoperative levels of N-terminal pro-brain natriuretic peptide (NT-proBNP) should decrease. This study investigated postoperative changes in NT-proBNP levels, the parameters related to changes, and the possible association with complications by performing a retrospective analysis of changes in daily NT-proBNP (pg/ml) levels from admission to discharge both before and after LVAD implantation in a tertiary referral center. For 72 patients implanted with HeartMate II LVADs, baseline NT-proBNP levels were elevated at 3,943 ng/ml (interquartile range 1,956 to 12,964). Preoperative stabilization led to marked decreases in NT-proBNP. Levels peaked 3 days after surgery and subsequently decreased. Patients with complicated postoperative courses had higher early postoperative elevations. By discharge, NT-proBNP decreased markedly but was still 2.83 (1.60 to 5.76) times the age-based upper limit of normal. The 26% reduction in NT-proBNP between admission and discharge was due mostly to the preoperative reductions and not those induced by the LVAD itself. The decrease was not associated with decreases in LV volume. In conclusion, preoperative treatment reduces NT-proBNP values. The magnitude of early postoperative changes is related to the clinical course. Levels at discharge remain markedly elevated and similar to values after preoperative stabilization despite presumptive acute LV unloading.

MR, CT, and PET imaging in pericardial disease

Although echocardiography remains the standard diagnostic tool for identifying pericardial diseases, procedures with better delineation of morphology and heart function are often required. The pericardium consists of an inner visceral (epicardium) and outer parietal layer (pericardium), which constitute for the pericardial cavity. Pericardial effusion can occur as transudate, exudate, pyopneumopericardium, or hemopericardium. Potential causes are inflammatory processes, that is, pericarditis due to autoimmune or infective reasons, neoplasms, irradiation, or systemic disorders, chronic renal failure, endocrine, or metabolic diseases. Pericardial fat can mimic pericardial effusion. Using various image-acquisition sequences, MRI allows identifying and separating fluid and solid structures. Fast spin-echo T1-weighted sequences with black-blood preparation are favourably used for morphological evaluation. Fast spin-echo T2-weighted sequences, particularly with fat saturation, and short-tau inversion-recovery sequences are useful to visualize oedema and inflammation. For further tissue characterization, delayed inversion-recovery imaging is used. Therefore, image acquisition is performed at 5-20 min subsequent to contrast agent administration, the so-called technique of late gadolinium enhancement. Ventricular volumes and myocardial mass can be assessed accurately by steady-state free-precession sequences, which is required to measure cardiac function and ventricular wall stress. Constrictive pericarditis usually results from chronic inflammatory processes leading to increased stiffness, which impedes the slippage of both pericardial layers and thereby the normal cardiac filling. CT imaging can favourably assess pericardial calcification. Thus, MR and CT imaging allow a comprehensive delineation of the pericardium. Superior to echocardiography, both methods provide a larger field of view and depiction of the complete chest including abnormalities of the surrounding mediastinum and lungs. PET provides unique information on the in vivo metabolism of 18-fluorodeoxyglucose that can be superimposed on CT findings and is useful for identifying inflammatory processes or masses, for example neoplasms. These imaging techniques provide advanced information of anatomy and cardiac function to optimize the pericardial access, for example by the AttachLifter system, for diagnosis and treatment.

Predictors and prevention of diabetic cardiomyopathy

Despite our cognizance that diabetes can enhance the chances of heart failure, causes multiorgan failure,and contributes to morbidity and mortality, it is rapidly increasing menace worldwide. Less attention has been paid to alert prediabetics through determining the comprehensive predictors of diabetic cardiomyopathy (DCM) and ameliorating DCM using novel approaches. DCM is recognized as asymptomatic progressing structural and functional remodeling in the heart of diabetics, in the absence of coronary atherosclerosis and hypertension. The three major stages of DCM are: (1) early stage, where cellular and metabolic changes occur without obvious systolic dysfunction; (2) middle stage, which is characterized by increased apoptosis, a slight increase in left ventricular size, and diastolic dysfunction and where ejection fraction (EF) is <50%; and (3) late stage, which is characterized by alteration in microvasculature compliance, an increase in left ventricular size, and a decrease in cardiac performance leading to heart failure. Recent investigations have revealed that DCM is multifactorial in nature and cellular, molecular, and metabolic perturbations predisposed and contributed to DCM. Differential expression of microRNA (miRNA), signaling molecules involved in glucose metabolism, hyperlipidemia, advanced glycogen end products, cardiac extracellular matrix remodeling, and alteration in survival and differentiation of resident cardiac stem cells are manifested in DCM. A sedentary lifestyle and high fat diet causes obesity and this leads to type 2 diabetes and DCM. However, exercise training improves insulin sensitivity, contractility of cardiomyocytes, and cardiac performance in type 2 diabetes. These findings provide new clues to diagnose and mitigate DCM. This review embodies developments in the field of DCM with the aim of elucidating the future perspectives of predictors and prevention of DCM.

Mechanisms involved in the differential reduction of omega-3 and omega-6 highly unsaturated fatty acids by structural heart disease resulting in "HUFA deficiency"

The causes of reduced levels of omega-3 and omega-6 highly unsaturated fatty acids ("HUFA deficiency") in heart failure remain unresolved. HUFA profiles were examined in the serum of 331 patients with failing versus nonfailing heart disease. Arachidonic acid was positively correlated (P < 0.001) with eicosapentaenoic acid (EPA) (r = 0.40) and docosahexaenoic acid (DHA) (r = 0.53) and negatively with palmitic (r = 0.42), palmitoleic (r = 0.38), and oleic acid (r = 0.48). Delta-5 desaturase activity was reduced (P < 0.01) in heart failure patients with low ejection fraction, dilatation, increased wall stress, and reduced heart rate variability (SDNN). In these patients, the reduced (P < 0.01) HUFA and increased palmitic (P < 0.01) and oleic acid (P = 0.05) arose from separate influences involving reduced cardiac contractility (arachidonic acid and palmitic acid predicted by ejection fraction) and chamber dilatation (DHA and oleic acid predicted by end-diastolic diameter). A low DHA (0.2%-0.9% versus 1.4%-3.1%) was associated (P < 0.025) with atrial dilatation (44 ± 8 mm versus 40 ± 8 mm). Equidirectional but less pronounced effects on HUFA were induced by sympathetic activation and (or) insulin resistance (fat and sugar fed to deoxycorticosterone acetate (DOCA)-salt rats) but not by compensated cardiac overload alone (DOCA-salt or aortic constriction), or reduced fatty acid oxidation (CPT-1 inhibition). Based on administration of omega-3 HUFA (OMACOR), dilatation is identified as a target for 1-2 g omega-3 HUFA·day(-1). Interventions for reduced arachidonic acid remain to be explored.

Diabetic cardiomyopathy--fact or fiction?

Epidemiologic as well as clinical studies confirm the close link between diabetes mellitus and heart failure. Diabetic cardiomyopathy (DCM) is still a poorly understood "entity", however, with several contributing pathogenetic factors which lead in different stages of diabetes to characteristic clinical phenotypes. Hyperglycemia with a shift from glucose metabolism to increased beta-oxidation and consecutive free fatty acid damage (lipotoxicity) to the myocardium, insulin resistance, renin-angiotensin-aldosterone system (RAAS) activation, altered calcium homeostasis and structural changes from the natural collagen network to a stiffer matrix due to advanced glycation endproduct (AGE) formation, hypertrophy and fibrosis contribute to the respective clinical phenotypes of DCM. We propose the following classification of cardiomyopathy in diabetic patients: a) Diastolic heart failure with normal ejection fraction (HFNEF) in diabetic patients often associated with hypertrophy without relevant hypertension. Relevant coronary artery disease (CAD), valvular disease and uncontrolled hypertension are not present. This is referred to as stage 1 DCM. b) Systolic and diastolic heart failure with dilatation and reduced ejection (HFREF) in diabetic patients excluding relevant CAD, valvular disease and uncontrolled hypertension as stage 2 DCM. c) Systolic and/or diastolic heart failure in diabetic patients with small vessel disease (microvascular disease) and/or microbial infection and/or inflammation and/or hypertension but without CAD as stage 3 DCM. d) If heart failure may also be attributed to infarction or ischemia and remodeling in addition to stage 3 DCM the term should be heart failure in diabetes or stage 4 DCM. These clinical phenotypes of diabetic cardiomyopathy can be separated by biomarkers, non-invasive (echocardiography, cardiac magnetic resonance imaging) and invasive imaging methods (levocardiography, coronary angiography) and further analysed by endomyocardial biopsy for concomitant viral infection. The role of specific diabetic drivers to the clinical phenotypes, to macro- and microangiopathy as well as accompanying risk factors or confounders, e.g. hypertension, autoimmune factors or inflammation with or without viral persistence, need to be identified in each individual patient separately. Thus hyperglycemia, hyperinsulinemia and insulin resistance as well as lipotoxicity by free fatty acids (FFAs) are the factors responsible for diabetic cardiomyopathy. In stage 1 and 2 DCM diabetic cardiomyopathy is clearly a fact. However, precise determination of to what degree the various underlying pathogenetic processes are responsible for the overall heart failure phenotype remains a fiction.

Intrapericardial procedures for cardiac regeneration by stem cells: need for minimal invasive access (AttachLifter) to the normal pericardial cavity

In view of the only modest functional and anatomical improvements achieved by bone marrow-derived cell transplantation in patients with heart disease, the question was addressed whether the intracoronary, transcoronary-venous, and intramyocardial delivery routes are adequate. It is hypothesized that an intrapericardial delivery of stem cells or activators of resident cardiac stem cells increases therapeutic benefits. From such an intrapericardial depot, cells or modulating factors, such as thymosin β4 or Ac-SDKP, are expected to reach the myocardium with sustained kinetics. Novel tools which provide access to the pericardial space even in the absence of pericardial effusion are, therefore, described. When the pericardium becomes attached to the suction head (monitored by an increase in negative pressure), the pericardium is lifted from the epicardium ("AttachLifter"). The opening of the suction head ("Attacher") is narrowed by flexible clamps which grab the tissue and improve the vacuum seal in the case of uneven tissue. A ridge, i.e.,"needle guidance", on the suction head excludes injury to the epicardium, whereby the pericardium is punctured by a needle which resides outside the suction head. A fiberscope can be used to inspect the pericardium prior to puncture. Based on these procedures, the role of the pericardial space and the presence of pericardial effusion in cardiac regeneration can be assessed.

Association of hyperhomocysteinemia with left ventricular dilatation and mass in human heart

BACKGROUND

Hyperhomocysteinemia is a risk factor for ischemic heart disease. Several other mechanisms apply also to dilative types of heart failure of various, non-ischemic etiologies. We hypothesized that hyperhomocysteinemia is associated with left ventricular (LV) dilatation and hypertrophy in dilative cardiomyopathy.

METHODS

Homocysteine was measured in 66 individuals with suspected cardiomyopathy. Cardiac magnetic resonance imaging was used to assess LV volume, mass, and wall stress.

RESULTS

Hyperhomocysteinemia (> 12 micromol/L) was found in 45 patients (68%). LV mass was greater in these patients compared with individuals with normal homocysteine (83+/-27 vs. 67+/-19 g/m(2); p<0.02). Homocysteine was increased in patients with increased brain natriuretic peptide > or = 100 pg/mL (18.3+/-5.9 vs. 14.9+/-5.1 micromol/L; p=0.018). LV mass, LV end-diastolic and end-systolic volume (LVEDV, LVESV) were significantly increased in individuals in the upper quartile compared with the lower quartile (90+/-25 vs. 65+/-18 g/m(2), p=0.021; 114+/-50 vs. 71+/-23 mL/m(2), p=0.042; 76+/-51 vs. 36+/-22 mL/m(2), p=0.045). LV dilatation (LVEDV > or = 90 mL/m(2)) was more common in hyperhomocysteinemia (> 12 micromol/L, p=0.0166). Normalized LV mass was correlated with homocysteine (r=0.346, p=0.065). Homocysteine was not significantly correlated with LVEDV (r=0.229, p=0.065), LV end-diastolic wall stress (r=0.226, p=0.069) and LV ejection fraction.

CONCLUSIONS

Hyperhomocysteinemia appears to be, at least in part, involved in a disproportional LV dilatation, where the ensuing hypertrophy is not sufficient to compensate for the increased wall stress. A potential mechanism is the hyperhomocysteinemia associated increase in oxidative stress that favors muscle fiber slippage.

Omacor (prescription omega-3-acid ethyl esters 90): From severe rhythm disorders to hypertriglyceridemia

Despite progress made in post-myocardial infarction (MI) revascularization and background therapy for the failing heart, the prevention of adverse cardiac remodeling associated with severe rhythm disorders remains an important drug target. Part of the remodeling can be counteracted by modulating the activity of ion channels and exchangers by omega-3 acids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). In the GISSI-Prevenzione and GISSI-HF trials, omega-3 fatty acids were administered as ethyl esters (Omacor Solvay Pharmaceuticals) and not as triglycerides present in fish oil. Ethyl esters result in a sustained intestinal absorption of EPA and DHA and require various purification steps during production, thereby minimizing the content of environmental toxins. Also the rather high (38%) DHA content of Omacor should not be ignored since in rats with low dose intake of omega-3 acids, DHA but not EPA inhibited ischemia-induced arrhythmias. In patients on multiple tablets, 840 mg EPA+DHA in one capsule is preferred to increase compliance. It is not justified to refer to Omacor as "n-3 polyunsaturated fatty acid supplementation" or even "fish oil" and, based on controlled clinical trials, there is no evidence that fish oil could be a substitute of Omacor. To avoid further confusion, guidelines should be precise and refer to the medication, eg, as in NICE guideline CG48: "Omega-3-acid ethyl esters treatment licensed for secondary prevention post-MI." The anti-arrhythmogenic action of Omacor should be seen in the context of implantable cardioverter-defibrillator trials (DINAMIT, IRIS) where non-sudden death was increased and total mortality unaltered. However, Omacor administered in the GISSI-HF trial reduced the incidence of severe arrhythmic events and mortality. Also in the GISSI-Prevenzione trial, arrhythmic death and mortality were reduced. At higher dosages (daily, 3-4 g) Omacor exhibits more pronounced cardiovascular benefits and, as a licensed indication, improves hypertriglyceridemia and related lipid parameters.

Protein NMR in biomedical research

Nuclear magnetic resonance (NMR) spectroscopy is a versatile biophysical technique with wide applicability in drug discovery research, particularly for the detection and characterization of molecular interactions. This review highlights in a comprehensive manner the aspects of biomolecular NMR which are most beneficial for pharmaceutical research and presents them as contributions to the different stages of a drug discovery program: target selection, assay development, lead generation and lead optimization. Emphasis is put on the concept of the particular NMR application, rather than on technical details, and on recent examples. Finally, an appendix of frequently asked questions is given.