Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0018801 (heart failure)
 72,216 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

An important determinant of cardiac output derives from the structure of the ventricular wall given by the arrangement of the cardiac muscle fibres. A key feature of this arrangement is both a global and local anisotropy. First, a preparation method necessary for analyzing the main aspects of spatial fibre architecture is outlined. Global anisotropy can be described by a gross band-like structure wrapping both left and right ventricles while local anisotropy results from the arrangement of the individual muscle fibres within the band. In pathologic cases this basic structure may be disturbed leading to cardiac failure. Second, a Finite Element model, formulated on the basis of Magnetic Resonance measurements has been devised which is intended to reflect the global as well as the local anisotropy of the ventricles in order to further the understanding of cardiac performance.
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PMID:The anisotropic structure of the human left and right ventricles. 913 17

Duchenne's progressive muscular dystrophy (DMD) is a genetic muscle disorder that causes degeneration and atrophy of the systemic and cardiac muscle. The disease is manifested early in childhood, and most of patients die by age 20 years of respiratory failure or heart failure. The cardiac involvement in DMD is characterized pathologically by degeneration and fibrosis of the myocardium, centering around the posterolateral wall of the left ventricle. Functionally, an abnormal electrocardiogram, valve motion, wall thickness, and wall motion are observed. Furthermore, abnormalities in plasma levels of atrial natriuretic peptide and autonomic function are also demonstrated. In this review, the cardiac involvements in DMD in the following aspects are described: 1) Electrocardiogram; a) high-frequency notches on the QRS complexes, b) amplitude of QRS complexes, c) late potential, d) arrhythmias, e) heart rate variability, f) a 10-year follow-up study, 2) Echocardiographic findings, 3) Hemodynamic findings, 4) Atrial natriuretic peptide.
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PMID:Cardiac involvement in progressive muscular dystrophy of the Duchenne type. 920 Nov 4

Phospholamban is a regulatory phosphoprotein which modulates the active transport of Ca2+ by the cardiac sarcoplasmic reticular Ca(2+)-ATPase enzyme (SERCA2) into the lumen of the sarcoplasmic reticulum. Phospholamban, which is a reversible inhibitor of SERCA2, represses the enzyme's activity, and this inhibition is relieved upon phosphorylation of phospholamban in response to beta-adrenergic stimulation. In this way, phospholamban is an important regulator of SERCA2-mediated myocardial relaxation during diastole. This report centers on the hypothesis that the relative levels of phospholamban: SERCA2 in cardiac muscle plays an important role in the muscle's overall contractility status. This hypothesis was tested by comparing the contractile parameters of: a) murine atrial and ventricular muscles, which differentially express phospholamban, and b) murine wild-type and phospholamban knock-out hearts. These comparisons revealed that atrial muscles, which have a 4.2-fold lower phospholamban: SERCA2 ratio than ventricular muscles, exhibited rates of force development and relaxation of tension, which were three-fold faster that these parameters for ventricular muscles. Similar comparisons were made via analyses of left-ventricular pressure development recorded for isolated, work-performing hearts from wild-type and phospholamban knock-out mice. In these studies, hearts from phospholamban knock-out mice, which were devoid of phospholamban, exhibited enhanced parameters of left-ventricular contractility in comparison to wild-type hearts. These results suggest that the relative phospholamban: SERCA2 ratio is critical in the regulation of myocardial contractility and alterations in this ratio may contribute to the functional deterioration observed during heart failure.
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PMID:The relative phospholamban and SERCA2 ratio: a critical determinant of myocardial contractility. 920 40

Report of a suicidal mono-intoxication with the class IC antiarrythmic drug propafenone. A 20-year-old female physician's assistant secretly ingested the substance (presumably 20 tablets per 300 mg) about 4-6 h before her death, and in the interim remained under the supervision of her physician. An ECG taken about 1/2-2 h after ingestion showed widening of the QRS complex and signs of an acute load of the right ventricle; the clinical symptoms were nausea, vomiting and hypotonia. After about 4 h without serious symptoms acute loss of consciousness and cardiac failure occurred, resuscitation efforts remained unsuccessful. At autopsy propafenone was found in blood (12 micrograms ml-1), liver (60 micrograms g-1) and cardiac muscle (11 micrograms g-1).
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PMID:Lethal suicidal intoxication with propafenone, after a history of self-inflicted injuries. 930 61

Mibefradil is the first of a new class of calcium antagonists with a unique structure and pharmacology. Its novel mechanism of action is characterized by L-type and selective T-type calcium channel blockade. Mibefradil is selective for smooth muscle over cardiac muscle and selectively dilates the coronary vasculature over the peripheral vasculature. In animal studies, mibefradil increases coronary blood flow during induced ischemia. In addition, in vitro studies demonstrated that mibefradil decreases smooth muscle proliferation in response to vascular injury. The most intriguing effects of mibefradil include a lack of negative inotropy and reflex tachycardia, as well as inhibition of pathologic hypertrophy and remodeling in response to vascular injury. In clinical trials, mibefradil (100 mg) was more effective than diltiazem dual-release capsules (360 mg) and as effective as amlodipine (10 mg) in treating mild-to-moderate hypertension; mibefradil (100 mg) also resulted in a greater reduction in sitting diastolic blood pressure than did nifedipine GITS (60 mg) in patients with moderate-to-severe hypertension. In patients with chronic stable angina, mibefradil (100 mg) was as effective as diltiazem SR capsules (120 mg) twice daily and more effective than amlodipine (10 mg) in improving exercise tolerance and reducing ischemic episodes. Mibefradil improved survival in a rat model of heart failure as effectively as the angiotensin-converting enzyme (ACE) inhibitor, cilazapril. The apparent lack of negative inotropic activity and neurohormonal activity with mibefradil, as well as its favorable effects on cardiac remodeling in experimental models, suggest that this agent may be beneficial in congestive heart failure. This hypothesis is being tested in the ongoing Mortality Assessment in Congestive Heart Failure (MACH-1) trial.
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PMID:Mibefradil: a selective T-type calcium antagonist. 937 39

Two isoforms of myosin heavy chain (MyHC), alpha and beta, exist in the mammalian ventricular myocardium, and their relative expression is correlated with the contractile velocity of cardiac muscle. Several pathologic stimuli can cause a shift in the MyHC composition of the rodent ventricle from alpha- to beta-MyHC. Given the potential physiological consequences of cardiac MyHC isoform shifts, we determined MyHC gene expression in human heart failure where cardiac contractility is impaired significantly. In this study, we quantitated the relative amounts of alpha- and beta-MyHC mRNA in the left ventricular free walls (LVs) of 14 heart donor candidates with no history of cardiovascular disease or structural cardiovascular abnormalities. This group consisted of seven patients with nonfailing (NF) hearts and seven patients with hearts that exhibited donor heart dysfunction (DHD). These were compared with 19 patients undergoing cardiac transplantation for chronic end-stage heart failure (F). The relative amounts of alpha-MyHC mRNA to total (i.e., alpha + beta) MyHC mRNA in the NF- and DHD-LVs were surprisingly high compared with previous reports (33.3+/-18.9 and 35.4+/-16.5%, respectively), and were significantly higher than those in the F-LVs, regardless of the cause of heart failure (2.2+/-3.5%, P < 0.0001). There was no significant difference in the ratios in NF- and DHD-LVs. Our results demonstrate that a considerable amount of alpha-MyHC mRNA is expressed in the normal heart, and is decreased significantly in chronic end-stage heart failure. If protein and enzymatic activity correlate with mRNA expression, this molecular alteration may be sufficient to explain systolic dysfunction in F-LVs, and therapeutics oriented towards increasing alpha-MyHC gene expression may be feasible.
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PMID:Myosin heavy chain gene expression in human heart failure. 941 Sep 16

The first case of chronic cardiac toxicity due to an antimalarial agent was reported in 1971 and since then several cases of heart failure, restrictive cardiomyopathy or atrioventricular block have been ascribed to this family of drugs. We report the case of a 43-year-old woman who developed juvenile chronic arthritis at the age of ten, followed in adulthood by sero-positive rheumatoid arthritis. In 1980 she was put under chloroquine sulfate (hydroxychloroquine was not available) in a dose of 200 mg/d (152.66 mg of chloroquine), with 10 mg/day of prednisone. She developed myalgia and increased skin pigmentation, but disregarded recommendations that these symptoms required discontinuation of chloroquine therapy. She was lost to follow-up, but continued the chloroquine therapy of her own accord. In December 1993, she developed a third-degree atrioventricular block with syncopes requiring implantation of a pacemaker. The rare but well-documented myopathy induced by antimalarial agents can produce early severe lesions of the cardiac muscle, which may have a predilection for the interventricular septum, explaining the risk of atrioventricular block. Although histologic studies were not performed in our patient, the clinical evidence of toxicity, absence of underlying heart disease and fairly young age of the patient pointed to chloroquine toxicity. Periodic cardiac investigations including electrocardiography may be warranted in patients under antimalarial therapy.
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PMID:Third-degree atrioventricular block in a patient under chloroquine therapy. 952 87

To probe the physiological role of calsequestrin in excitation-contraction coupling, transgenic mice overexpressing cardiac calsequestrin were developed. Transgenic mice exhibited 10-fold higher levels of calsequestrin in myocardium and survived into adulthood, but had severe cardiac hypertrophy, with a twofold increase in heart mass and cell size. In whole cell-clamped transgenic myocytes, Ca2+ channel- gated Ca2+ release from the sarcoplasmic reticulum was strongly suppressed, the frequency of occurrence of spontaneous or Ca2+ current-triggered "Ca2+ sparks" was reduced, and the spark perimeter was less defined. In sharp contrast, caffeine-induced Ca2+ transients and the resultant Na+-Ca2+ exchanger currents were increased 10-fold in transgenic myocytes, directly implicating calsequestrin as the source of the contractile-dependent pool of Ca2+. Interestingly, the proteins involved in the Ca2+-release cascade (ryanodine receptor, junctin, and triadin) were downregulated, whereas Ca2+-uptake proteins (Ca2+-ATPase and phospholamban) were unchanged or slightly increased. The parallel increase in the pool of releasable Ca2+ with overexpression of calsequestrin and subsequent impairment of physiological Ca2+ release mechanism show for the first time that calsequestrin is both a storage and a regulatory protein in the cardiac muscle Ca2+-signaling cascade. Cardiac hypertrophy in these mice may provide a novel model to investigate the molecular determinants of heart failure.
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PMID:Regulation of Ca2+ signaling in transgenic mouse cardiac myocytes overexpressing calsequestrin. 952 81

An autopsy case of a 58-year-old woman with massive cardiac involvement of adult T cell leukemia/lymphoma (ATLL) is reported. She developed cardiac failure due to aortic and mitral regurgitation with cardiac infiltration of ATLL cells, and underwent replacement of both aortic and mitral valves. Studies of the cut-surfaces revealed diffuse thickening of the subendocardial wall of the left chamber with widespread whitish-brown tumor infiltrates. In the regions surrounding the replaced aortic and mitral valves there was also massive tumor cell infiltration. The tumor cells infiltrating the cardiac muscle wall were T cell in origin and exhibited Leu-3a (CD4)-positive immunoreaction. Ultrastructurally, tumor cells contained markedly indented nuclei and some were attached directly to the muscle cells. These findings suggest that this was an unusual form of ATLL with widespread involvement of the heart.
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PMID:Adult T cell leukemia/lymphoma with massive involvement of cardiac muscle and valves. 958 91

New effective therapies have been producing longer survival times for HIV-patients. Thus non-infectious complications of late stage of HIV infection (such as the development of left ventricular dysfunction) have emerged; in fact cardiac involvement has been identified frequently at autopsy and is described in 80% of patients with acquired immunodeficiency syndrome (AIDS) as an evidence of the virus cardiotrophism, while clinical findings of left ventricular dysfunction were only detected in about 15% of the patients. It is possible that the development of heart failure had been underestimated in those years; in fact signs and symptoms of cardiac involvement had been often misinterpreted as the results of non cardiac causes (pulmonary failure or infections) also determining a delay in the beginning of cardiac therapy. The aim of this study was to follow 16 human immunodeficiency-virus positive patients during a 3-year period to evaluate the usefulness of early detection of heart failure in order to start a specific therapy as soon as possible. The follow-up consisted of a clinical and electrocardiographic control every 4 months. Echocardiography was carried out when involvement of the cardiac muscle was suspected. During the follow-up we could reveal an early involvement in 5/16 patients (31.2%) and in 2 of them (40%) early therapy caused clinical and echocardiographic regression of left ventricular dysfunction. The present study demonstrates that periodical clinical and echocardiographic controls are useful in patients with HIV infection.
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PMID:[Early detection of heart involvement using serial cardiologic controls in the follow-up of patients with AIDS]. 961 56


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