Dimitrios Th. Kremastinos

Mid-Region Pro-Hormone Markers for Diagnosis and Prognosis in Acute Dyspnea: Results From the BACH (Biomarkers in Acute Heart Failure) Trial

OBJECTIVES Our purpose was to assess the diagnostic utility of mid-regional pro-atrial natriuretic peptide (MR-proANP) for the diagnosis of acute heart failure (AHF) and the prognostic value of mid-regional pro-adrenomedullin (MR-proADM) in patients with AHF. BACKGROUND There are some caveats and limitations to natriuretic peptide testing in the acute dyspneic patient. METHODS The BACH (Biomarkers in Acute Heart Failure) trial was a prospective, 15-center, international study of 1,641 patients presenting to the emergency department with dyspnea. A noninferiority test of MR-proANP versus B-type natriuretic peptide (BNP) for diagnosis of AHF and a superiority test of MR-proADM versus BNP for 90-day survival were conducted. Other end points were exploratory. RESULTS MR-proANP (> or =120 pmol/l) proved noninferior to BNP (> or =100 pg/ml) for the diagnosis of AHF (accuracy difference 0.9%). In tests of secondary diagnostic objectives, MR-proANP levels added to the utility of BNP levels in patients with intermediate BNP values and with obesity but not in renal insufficiency, the elderly, or patients with edema. Using cut-off values from receiver-operating characteristic analysis, the accuracy to predict 90-day survival of heart failure patients was 73% (95% confidence interval: 70% to 77%) for MR-proADM and 62% (95% confidence interval: 58% to 66%) for BNP (difference p < 0.001). In adjusted multivariable Cox regression, MR-proADM, but not BNP, carried independent prognostic value (p < 0.001). Results were consistent using NT-proBNP instead of BNP (p < 0.001). None of the biomarkers was able to predict rehospitalization or visits to the emergency department with clinical relevance. CONCLUSIONS MR-proANP is as useful as BNP for AHF diagnosis in dyspneic patients and may provide additional clinical utility when BNP is difficult to interpret. MR-proADM identifies patients with high 90-day mortality risk and adds prognostic value to BNP. (Biomarkers in Acute Heart Failure [BACH]; NCT00537628).

Human phospholamban null results in lethal dilated cardiomyopathy revealing a critical difference between mouse and human

In human disease and experimental animal models, depressed Ca(2+) handling in failing cardiomyocytes is widely attributed to impaired sarcoplasmic reticulum (SR) function. In mice, disruption of the PLN gene encoding phospholamban (PLN) or expression of dominant-negative PLN mutants enhances SR and cardiac function, but effects of PLN mutations in humans are unknown. Here, a T116G point mutation, substituting a termination codon for Leu-39 (L39stop), was identified in two families with hereditary heart failure. The heterozygous individuals exhibited hypertrophy without diminished contractile performance. Strikingly, both individuals homozygous for L39stop developed dilated cardiomyopathy and heart failure, requiring cardiac transplantation at ages 16 and 27. An over 50% reduction in PLN mRNA and no detectable PLN protein were noted in one explanted heart. The expression of recombinant PLN-L39stop in human embryonic kidney (HEK) 293 cells and adult rat cardiomyocytes showed no PLN inhibition of SR Ca(2+)-ATPase and the virtual absence of stable PLN expression; where PLN was expressed, it was misrouted to the cytosol or plasma membrane. These findings describe a naturally-occurring loss-of-function human PLN mutation (PLN null). In contrast to reported benefits of PLN ablation in mouse heart failure, humans lacking PLN develop lethal dilated cardiomyopathy.

Ascorbic Acid Prevents Contrast-Mediated Nephropathy in Patients With Renal Dysfunction Undergoing Coronary Angiography or Intervention

Background—Contrast agents can cause a reduction in renal function that may be due to the generation of reactive oxygen species. Conflicting evidence suggests that administration of the antioxidant acetylcysteine prevents this renal impairment. The action of other antioxidant agents has not been investigated. Methods and Results—We conducted a randomized, double-blind, placebo-controlled trial of ascorbic acid in 231 patients with a serum creatinine concentration ≥1.2 mg/dL who underwent coronary angiography and/or intervention. Ascorbic acid, 3 g at least 2 hours before the procedure and 2 g in the night and the morning after the procedure, or placebo was administered orally. Contrast-mediated nephropathy was defined by an absolute increase of serum creatinine ≥0.5 mg/dL or a relative increase of ≥25% measured 2 to 5 days after the procedure. Contrast-mediated nephropathy occurred in 11 of the 118 patients (9%) in the ascorbic acid group and in 23 of the 113 patients (20%) in the placebo group (odds ratio [OR], 0.38; 95% confidence interval [CI], 0.17 to 0.85; P=0.02). The mean serum creatinine concentration increased significantly in the placebo group (from 1.36±0.50 to 1.50±0.54 mg/dL, P<0.001) and nonsignificantly in the ascorbic acid group (from 1.46±0.52 to 1.52±0.64 mg/dL, P=0.07). The mean increase in serum creatinine concentration was greater in the placebo group than in the ascorbic acid group (difference of 0.09 mg/dL; 95% CI, 0.00 to 0.17; P=0.049). Conclusions—Prophylactic oral administration of ascorbic acid may protect against contrast-mediated nephropathy in high-risk patients undergoing a coronary procedure.

Physical training modulates proinflammatory cytokines and soluble fas-soluble fas ligand system in patients with chronic heart failure

OBJECTIVES We sought to investigate the effects of physical training on circulating proinflammatory cytokines and the soluble apoptosis mediators Fas (sFas) and Fas ligand (sFasL) in patients with chronic heart failure (CHF). BACKGROUND Recent investigations have shown an overexpression of circulating proinflammatory cytokines and soluble apoptosis mediators in patients with CHF, which may be related to their exercise intolerance and clinical deterioration. METHODS Plasma levels of tumor necrosis factor-alpha (TNF-alpha), soluble TNF receptors I and II (sTNF-RI and sTNF-RII, respectively), interleukin-6 (IL-6), soluble IL-6 receptor (sIL-6R), sFas and sFasL were measured in 24 patients with stable CHF (New York Heart Association functional class II/III; left ventricular ejection fraction 23.2 +/- 1.3%) and in 20 normal control subjects before and after a 12-week program of physical training in a randomized, crossover design. Functional status of patients with CHF was evaluated by using a cardiorespiratory exercise test to measure peak oxygen consumption (VO2max). RESULTS Physical training produced a significant reduction in plasma levels of TNF-alpha (7.5 +/- 1.0 pg/ml vs. 4.6 +/- 0.7 pg/ml, p < 0.001), sTNF-RI (3.3 +/- 0.2 ng/ml vs. 2.7 +/- 0.2 ng/ml, p < 0.005), sTNF-RII (2.6 +/- 0.2 ng/ml vs. 2.3 +/- 0.2 ng/ml, p = 0.06), IL-6 (8.3 +/- 1.2 pg/ml vs. 5.9 +/- 0.8 pg/ml, p < 0.005), sIL-6R (34.0 +/- 3.0 ng/ml vs. 29.2 +/- 3.0 ng/ml, p < 0.01), sFas (5.5 +/- 0.7 ng/ml vs. 4.5 +/- 0.8 ng/ml, p = 0.05) and sFasL (34.9 +/- 5.0 pg/ml vs. 25.2 +/- 4.0 pg/ml, p < 0.05), as well as a significant increase in VO2max (16.3 +/- 0.7 ml/kg per min vs. 18.7 +/- 0.8 ml/kg per min, p < 0.001). Good correlations were found between a training-induced increase in VO2max and a training-induced reduction in levels of the proinflammatory cytokine TNF-alpha (r = -0.54, p < 0.01) and the apoptosis inducer sFasL (r = -0.57, p < 0.005) in patients with CHF. In contrast, no significant difference in circulating cytokines and apoptotic markers was found with physical training in normal subjects. CONCLUSIONS Physical training reduces plasma levels of proinflammatory cytokines and the sFas/sFasL system in patients with CHF. These immunomodulatory effects may be related to the training-induced improvement in functional status of patients with CHF.

A mutation in the human phospholamban gene, deleting arginine 14, results in lethal, hereditary cardiomyopathy

The sarcoplasmic reticulum Ca2+-cycling proteins are key regulators of cardiac contractility, and alterations in sarcoplasmic reticulum Ca2+-cycling properties have been shown to be causal of familial cardiomyopathies. Through genetic screening of dilated cardiomyopathy patients, we identified a previously uncharacterized deletion of arginine 14 (PLN-R14Del) in the coding region of the phospholamban (PLN) gene in a large family with hereditary heart failure. No homozygous individuals were identified. By middle age, heterozygous individuals developed left ventricular dilation, contractile dysfunction, and episodic ventricular arrhythmias, with overt heart failure in some cases. Transgenic mice overexpressing the mutant PLN-R14Del recapitulated human cardiomyopathy exhibiting similar histopathologic abnormalities and premature death. Coexpression of the normal and mutant-PLN in HEK-293 cells resulted in sarcoplasmic reticulum Ca2+-ATPase superinhibition. The dominant effect of the PLN-R14Del mutation could not be fully removed, even upon phosphorylation by protein kinase A. Thus, by chronic suppression of sarcoplasmic reticulum Ca2+-ATPase activity, the nonreversible superinhibitory function of mutant PLN-R14Del may lead to inherited dilated cardiomyopathy and premature death in both humans and mice.

Inhibition of Interleukin-1 by Anakinra Improves Vascular and Left Ventricular Function in Patients With Rheumatoid Arthritis

Background— Interleukin-1 increases nitrooxidative stress. We investigated the effects of a human recombinant interleukin-1a receptor antagonist (anakinra) on nitrooxidative stress and vascular and left ventricular function. Methods and Results— In an acute, double-blind trial, 23 patients with rheumatoid arthritis were randomized to receive a single injection of anakinra (150 mg SC) or placebo and, after 48 hours, the alternative treatment. At baseline and 3 hours after the injection, we assessed (1) coronary flow reserve, aortic distensibility, systolic and diastolic (Em) velocity of the mitral annulus, and E to Em ratio (E/Em) using echocardiography; (2) flow-mediated, endothelium-dependent dilation of the brachial artery; and (3) malondialdehyde, nitrotyrosine, interleukin-6, endothelin-1, and C-reactive protein. In a chronic, nonrandomized trial, 23 patients received anakinra and 19 received prednisolone for 30 days, after which all indices were reassessed. Compared with baseline, there was a greater reduction in malondialdehyde, nitrotyrosine, interleukin-6, and endothelin-1 and a greater increase in flow-mediated dilation, coronary flow reserve, aortic distensibility, systolic velocity of mitral annulus, and E/Em after anakinra than after placebo (malondialdehyde −25% versus 9%; nitrotyrosine −38% versus −11%; interleukin-6 −29% versus 0.9%; endothelin-1 −36% versus −11%; flow-mediated dilation 45% versus −9%; coronary flow reserve 29% versus 4%; and aortic distensibility 45% versus 2%; P<0.05 for all comparisons). After 30 days of treatment, the improvement in biomarkers and in vascular and left ventricular function was greater in the anakinra group than in the prednisolone group (P<0.05). Conclusions— Interleukin-1 inhibition improves vascular and left ventricular function and is associated with reduction of nitrooxidative stress and endothelin.

Ischemic postconditioning: experimental models and protocol algorithms

Ischemic postconditioning, a simple mechanical maneuver at the onset of reperfusion, reduces infarct size after ischemia/reperfusion. After its first description in 2003 by Zhao et al. numerous experimental studies have investigated this protective phenomenon. Whereas the underlying mechanisms and signal transduction are not yet understood in detail, infarct size reduction by ischemic postconditioning was confirmed in all species tested so far, including man. We have now reviewed the literature with focus on experimental models and protocols to better understand the determinants of protection by ischemic postconditioning or lack of it. Only studies with infarct size as unequivocal endpoint were considered. In all species and models, the duration of index ischemia and the protective protocol algorithm impact on the outcome of ischemic postconditioning, and gender, age, and myocardial temperature contribute.

Methods for evaluating endothelial function: a position statement from the European Society of Cardiology Working Group on Peripheral Circulation

The endothelium holds a pivotal role in cardiovascular health and disease. Assessment of its function was until recently limited to experimental designs due to its location. The advent of novel techniques has facilitated testing on a more detailed basis, with focus on distinct pathways. This review presents available in-vivo and ex-vivo methods for evaluating endothelial function with special focus on more recent ones. The diagnostic modalities covered include assessment of epicardial and microvascular coronary endothelial function, local vasodilation by venous occlusion plethysmography and flow-mediated dilatation, arterial pulse wave analysis and pulse amplitude tonometry, microvascular blood flow by laser Doppler flowmetry, biochemical markers and bioassays, measurement of endothelial-derived microparticles and progenitor cells, and glycocalyx measurements. Insights and practical information on the theoretical basis, methodological aspects, and clinical application in various disease states are discussed. The ability of these methods to detect endothelial dysfunction before overt cardiovascular disease manifests make them attractive clinical tools for prevention and rehabilitation.

Polyphenols compounds from red grapes acutely improve endothelial function in patients with coronary heart disease

Background It has been shown that acute intake of red wine improves endothelial-dependent vasodilatation. It is not clear, however, which constituents of red wine are responsible for this effect. We examined whether acute intake of a red grape polyphenol extract has a positive effect on brachial artery flow-mediated dilatation. Methods We recruited 30 male patients with coronary heart disease. They were randomly assigned either to a red grape polyphenol extract (600 mg) dissolved in 20 ml of water (n = 15) or 20 ml of water (placebo) (n = 15). The extract of grapes contained 4.32 mg epicatechin, 2.72 mg catechin, 2.07 mg gallic acid, 0.9 mg trans-resveratrol, 0.47 mg rutin, 0.42 mg ε-viniferin, 0.28 mg, p-coumaric acid, 0.14 mg ferulic acid and 0.04 mg quercetin per gram. Flow-mediated dilatation of the brachial artery was evaluated after reactive hyperemia induced by cuff obstruction of the forearm, using high-resolution ultasonography. Particularly, flow-mediated dilatation was measured after fasting and 30, 60 and 120 min after the intake of the grape extract or placebo. Results Intake of the red grape polyphenol extract caused an increase in flow-mediated dilatation, peaking at 60 min, which was significantly higher than the baseline values (4.52 ± 1.34 versus 2.6 ± 1.5%; P < 0.001) and the corresponding values at 60 min after the intake of placebo (4.52 ± 1.34 versus 2.64 ± 1.8%, P < 0.001). There was no change in FMD values after the intake of placebo throughout the whole duration of the study. Conclusion Polyphenolic compounds from red grapes acutely improve endothelial function in patients with coronary heart disease. These results could probably, at least partly, explain the favorable effects of red wine on the cardiovascular system.

Left ventricular diastolic Doppler characteristics in beta-thalassemia major.

BACKGROUND Diastolic left ventricular function expressed by diastolic Doppler characteristics of the left ventricle has never been properly investigated. METHODS AND RESULTS Left ventricular inflow and pulmonary vein flow patterns were assessed by Doppler echocardiography in 88 beta-thalassemia major patients with normal left ventricular systolic function; 34 were young (age, 15.1 +/- 3.2 years) and 54 were adults (age, 25.1 +/- 3.6 years). The findings were compared with those obtained from 22 young (age, 13.8 +/- 2.4 years) and 24 adult (age, 25.3 +/- 4.1 years) normal individuals. In both groups of patients, peak flow velocities in early (E) and late (A) diastole were higher than in the control subjects (young E: P < .01; adult E: P < .001; young A: P < .05; adult A: P < .05), whereas no difference was found in the E/A ratio, deceleration time, or isovolumic relaxation time. Pulmonary vein systolic (S) and diastolic (D) velocities were also higher in beta-thalassemia major patients compared with the control subjects (young S: P < .05; adult S: P < .05; young D: P < .05; adult D: P < .05). Restrictive left ventricular abnormalities were only found in 7 patients who were among the oldest beta-thalassemia major population of the adult group (P < .01) with highly elevated mean serum ferritin. In comparison to the remaining adult patients, interventricular septum and left ventricular posterior wall thickness were increased (P < .01 and P < .01, respectively). The left atrium and right ventricle were dilated (P < .05 and P < .01, respectively). CONCLUSIONS Doppler diastolic indexes in beta-thalassemia major patients with normal left ventricular systolic function are similar to those seen in conditions with an increased preload, probably because of chronic anemia. Only severe iron loading and deposition in the myocardium leads to the restrictive abnormalities of left ventricular filling.