PURPOSE: To assess cardiac structural and functional changes induced by competitive amateur cycling. METHODS: Fifty-one young competitive amateur male cyclists and 47 age- and gender-matched control subjects underwent complex transthoracic echocardiographic examination focused on the detailed assessment of cardiac size and function, especially of the left ventricle (LV). Subsequently, spiroergometry was performed in all study participants and its results were compared to echocardiographic data. RESULTS: Higher left ventricular mass indexes due to the greater LV wall thickness and LV end-diastolic diameter were found in amateur cyclists as compared to control subjects. There were no differences with regard to the LV systolic function parameters. However, significantly better indices of LV diastolic function were present in cyclists. A significant correlation between maximal oxygen pulse and LV mass index/height(2.7), LV diastolic parameters and right ventricular size was noted. CONCLUSIONS: Amateur competitive cycling leads to considerable LV structural and functional changes. The increases in LV wall thickness and cavity size together with supranormal diastolic properties are key characteristics of this LV remodeling. As well, LV mass, diastolic function, and RV size are predictors of exercise capacity, indicating an important involvement of these elements in improving cardiac function with endurance training.
- MeSH
- Bicycling physiology MeSH
- Ventricular Function, Left physiology MeSH
- Competitive Behavior MeSH
- Humans MeSH
- Young Adult MeSH
- Heart Ventricles ultrasonography MeSH
- Physical Exertion physiology MeSH
- Physical Fitness physiology MeSH
- Organ Size MeSH
- Check Tag
- Humans MeSH
- Young Adult MeSH
- Male MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
- Comparative Study MeSH
The amyloidoses represent a group of diseases characterized by extracellular deposition of abnormal protein, amyloid, which is formed by insoluble extracellular fibrils in β-pleated sheets. Although cardiac involvement may occur in all types of amyloidoses, clinically relevant amyloid cardiomyopathy is a typical feature of AL amyloidosis and transthyretin-related amyloidoses. Congestive heart failure represents the commonest manifestation of amyloid heart disease. Noninvasive imaging techniques, especially echocardiography and cardiac magnetic resonance, play a major role in the diagnosis of amyloid cardiomyopathy; however, histological confirmation and exact typing of amyloid deposits is necessary whether in extracardiac location or directly in the myocardium. Early diagnosis of amyloid heart disease is of utmost importance as the presence and especially the severity of cardiac involvement generally drives the prognosis of affected subjects and plays a major role in determining the intensity of specific treatment, namely in AL amyloidosis. The management of patients with amyloid heart disease is complex. Loop diuretics together with aldosterone antagonists represent the basis for influencing signs of congestion. In AL amyloidosis, high-dose chemotherapy followed by autologous stem cell transplantation is generally considered to be a front-line treatment option, if the disease is diagnosed at its early stage. The combination of mephalan with dexamethasone has been the standard therapy for severely affected individuals; however, the combinations with several novel agents including immunomodulatory drugs and bortezomibe have been tested in clinical trials with promising results. New therapeutic substances with the potential to slow or even stop the progression of transthyretin-related amyloidosis are also extensively studied.
- MeSH
- Amyloid metabolism MeSH
- Amyloidosis diagnosis metabolism therapy MeSH
- Transplantation, Autologous MeSH
- Humans MeSH
- Heart Diseases diagnosis metabolism therapy MeSH
- Antineoplastic Combined Chemotherapy Protocols therapeutic use MeSH
- Hematopoietic Stem Cell Transplantation * MeSH
- Check Tag
- Humans MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
- Review MeSH
Dilated cardiomyopathy (DCM) represents the third most common cause of heart failure and the most frequent cause of heart transplantation. Infectious, mostly viral, and autoimmune mechanisms, together with genetic abnormalities, have been reported as three major causes of DCM. We hypothesized that Lyme disease (LD), caused by spirochete Borrelia burgdorferi (Bb), might be an important cause of new-onset unexplained DCM in patients living in a highly endemic area for LD such as the Czech Republic. We performed endomyocardial biopsy (EMB) in 39 consecutive patients presenting with symptomatic unexplained left ventricular (LV) systolic dysfunction lasting no more than 12 months. In eight subjects (21%), Bb was detected in the EMB sample by polymerase chain reaction or by electron microscopy. None of these patients exhibited any form of atrioventricular block or other extracardiac manifestation of Bb infection. Serological testing identified IgG antibodies against Bb in only two cases and IgM antibodies in none. All affected patients were treated with intravenous ceftriaxone for 3 weeks. At 6 months follow-up, LV morphology and function as well as functional status of these patients significantly improved. In conclusion, Bb infection may represent an important cause of new-onset unexplained DCM in patients living in endemic regions such as the Czech Republic. Because the antibiotic treatment appears to be markedly effective and serological examination does not provide a tool for diagnosing the disease, EMB focused on the detection of Bb should be performed in all patients from endemic areas with new-onset unexplained DCM not responding to conventional therapy.
- MeSH
- Anti-Bacterial Agents therapeutic use MeSH
- Biopsy MeSH
- Borrelia burgdorferi isolation & purification MeSH
- Ceftriaxone therapeutic use MeSH
- Cardiomyopathy, Dilated etiology microbiology MeSH
- Adult MeSH
- Ventricular Dysfunction, Left etiology microbiology MeSH
- Microscopy, Electron MeSH
- Middle Aged MeSH
- Humans MeSH
- Lyme Disease complications drug therapy MeSH
- Myocardium pathology MeSH
- Polymerase Chain Reaction MeSH
- Prevalence MeSH
- Antibodies, Bacterial blood MeSH
- Check Tag
- Adult MeSH
- Middle Aged MeSH
- Humans MeSH
- Male MeSH
- Female MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
- Geographicals
- Czech Republic MeSH
Inflammatory dilated cardiomyopathy (DCMi) represents an acquired form of dilated cardiomyopathy. Viral infection is the most common cause of DCMi. In contrast with other cardiotropic viruses, herpes simplex virus (HSV) is a very rare finding in endomyocardial biopsies of patients with dilated cardiomyopathy. We report a case of HSV-induced cardiomyopathy successfully treated with acyclovir.
- MeSH
- Acyclovir therapeutic use MeSH
- Antiviral Agents therapeutic use MeSH
- Cardiomyopathy, Dilated drug therapy etiology MeSH
- Herpes Simplex complications drug therapy MeSH
- Middle Aged MeSH
- Humans MeSH
- Myocarditis drug therapy etiology MeSH
- Treatment Outcome MeSH
- Check Tag
- Middle Aged MeSH
- Humans MeSH
- Male MeSH
- Publication type
- Journal Article MeSH
- Case Reports MeSH
- Research Support, Non-U.S. Gov't MeSH
Stormorken syndrome is a multiorgan hereditary disease caused by dysfunction of the endoplasmic reticulum (ER) Ca2+ sensor protein STIM1, which forms the Ca2+ release-activated Ca2+ (CRAC) channel together with the plasma membrane channel Orai1. ER Ca2+ store depletion activates STIM1 by releasing the intramolecular "clamp" formed between the coiled coil 1 (CC1) and CC3 domains of the protein, enabling the C terminus to extend and interact with Orai1. The most frequently occurring mutation in patients with Stormorken syndrome is R304W, which destabilizes and extends the STIM1 C terminus independently of ER Ca2+ store depletion, causing constitutive binding to Orai1 and CRAC channel activation. We found that in cis deletion of one amino acid residue, Glu296 (which we called E296del) reversed the pathological effects of R304W. Homozygous Stim1 E296del+R304W mice were viable and phenotypically indistinguishable from wild-type mice. NMR spectroscopy, molecular dynamics simulations, and cellular experiments revealed that although the R304W mutation prevented CC1 from interacting with CC3, the additional deletion of Glu296 opposed this effect by enabling CC1-CC3 binding and restoring the CC domain interactions within STIM1 that are critical for proper CRAC channel function. Our results provide insight into the activation mechanism of STIM1 by clarifying the molecular basis of mutation-elicited protein dysfunction and pathophysiology.
- MeSH
- Amino Acids metabolism MeSH
- Endoplasmic Reticulum metabolism MeSH
- Calcium Release Activated Calcium Channels * genetics MeSH
- Membrane Proteins * metabolism MeSH
- Mutation MeSH
- Mice MeSH
- ORAI1 Protein metabolism MeSH
- Stromal Interaction Molecule 1 genetics MeSH
- Calcium metabolism MeSH
- Calcium Channels metabolism MeSH
- Animals MeSH
- Check Tag
- Mice MeSH
- Animals MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH