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T Meinertz

Publications and source records attributed to T Meinertz.

At least 19 recordsLinked to original sources
PubMed2007

[Patterns of delayed-enhancement in MRI of ischemic and non-ischemic cardiomyopathies].

Contrast-enhanced MRI using the delayed-enhancement technique (DE-MRI) is widely applied in the clinical work-up of myocardial diseases. Myocardial diseases of varying etiology result in myocardial changes, such as necrosis, fibrosis, edema and metabolite deposition, which can be visualized by DE-MRI. Acute and chronic ischemic diseases based on a coronary artery disease as well as non-ischemic cardiomyopathies display DE. Cardiomyopathies often show a characteristic enhancement pattern. While ischemic lesions are localized in the subendocardium, non-ischemic cardiomyopathies often display an intramyocardial or subepicardial pattern. The typical pattern for dilated cardiomyopathies is band-like and intramyocardial with septal involvement. Arrhythmogenic right-ventricular dysplasias/cardiomyopathies are frequently associated with right-ventricular DE. In the case of amyloid cardiomyopathies which are often restrictive cardiomyopathies, subendocardial and circular DE is typically observed. Hypertrophic cardiomyopathies display patchy intramyocardial DE usually in the anteroseptal region. Acute myocarditis is typically accompanied by intramyocardial or subepicardial DE affecting the lateral wall. In the case of chronic myocarditis, intramyocardial or subepicardial DE is observed most frequently. Cardiac sarcoidosis typically entails patchy subepicardial DE with right- and left-ventricular involvement. Since there is an overlap between the enhancement patterns of cardiomyopathies, the diagnostic accuracy of DE-MRI is limited and the diagnosis must be based on additional clinical and MRI findings. The amount of DE often corresponds with cardiac functional parameters as well as with the frequency of cardiac events so that DE-MRI may be useful for risk stratification. Furthermore, DE-MRI can be helpful in the planning and evaluation of myocardial biopsies and electrophysiological examinations.

Acute Disease↗
PubMed2006

Trapidil is as effective as isosorbide-dinitrate for treating stable angina pectoris: a multinational, multicenter, double-blind, randomized study.

OBJECTIVE: Nitrates have long been used in the treatment of stable angina pectoris. We set out to show that trapidil, a triazolo-pyrimidine with a mode of action different from that of nitrates, is not inferior to isosorbide-dinitrate (ISDN) in the treatment of this clinical syndrome. PATIENTS AND METHODS: We studied the efficacy of 200 mg trapidil (t.i.d.) vs. ISDN (20 mg b.i.d.) in patients with chronic stable angina treated for 12 weeks. The therapeutic effect was measured in terms of responder rate as change in total exercise time (TET) by at least 60 seconds using the bicycle ergometer test. RESULTS: A total of 648 patients were included in the study. Responder rates in the Per- Protocol (PP) population (n = 529) were 50.4% (n = 133) in the trapidil group and 52.5% (n = 139) in the ISDN group (p = 0.233). As the lower non-inferiority limit (-15%) was clearly excluded from the 95% CI (pp: -10.6%, +6.4%; ITT -9.7%, 5.7%), non-inferiority of trapidil compared to ISDN can be concluded. Trapidil 200 mg t.i.d. combined with short-acting NTG prn as rescue medication over 12 weeks in subjects with chronic stable angina pectoris proved to have similar effects on TET and on other clinical endpoints as ISDN 20 mg b.i.d. The secondary efficacy analyses did not reveal any clinically relevant differences between treatment groups, and were not in conflict with the non-inferiority claim. Patients in the ISDN group had significantly more headache (34.1%; n = 110) compared to those taking trapidil (19.3%, n = 62; p <0.0001). CONCLUSIONS: Overall results of this study show that both drugs are equally effective and safe for the short-term treatment of patients with chronic stable angina pectoris and that trapidil can be considered as therapeutically equivalent to ISDN.

Adult↗
PubMed2006

[Current concepts of diabetic atherogenesis].

Morbidity and mortality in patients with diabetes is mainly driven by its vascular manifestations. The underlying pathophysiology of diabetes is centrally linked to increased generation of reactive oxygen species, namely superoxide and hydrogen peroxide. Superoxide, generated upon uncoupling of the mitochondrial respiratory chain, oxidizes endothelial-derived nitric oxide and thus impairs endothelial function. Superoxide-derived hydrogen peroxide is the principal substrate for leukocyte-derived peroxidases, in particular myeloperoxidase, which associates with endothelial cells and has been shown to catalytically oxidize nitric oxide in vivo. Superoxide also promotes synthesis of advanced glycation endproducts, which also exert potent proatherogenic properties. Moreover, superoxide and hydrogen peroxide activate the redox-sensitive transcription factors NF-kappaB and thus mediates expression of proinflammatory proteins like adhesion molecules. Herein some the most recent discoveries in the pathophysiology of diabetic vasculopathy are reviewed.

Diabetic Angiopathies↗
PubMed2005

[Antiarrhythmic therapy--recent aspects of pharmacologic treatment].

Over the last years the indication for antiarrhythmic therapy has changed due to the development of other therapeutic approaches. However, antiarrhythmics are important in the acute treatment as well as the prevention of recurrent rhythm disorders. In line with the antiarrhythmic agents of class IC and III also beta-blockers, ACE inhibitors and AT (1) antagonists can be used primarily with a lower risk of severe cardiac side effects. Recent studies demonstrate that for patients with atrial fibrillation there was no benefit of rhythm control versus rate control. However, rhythm control with antiarrhythmics is beneficial in the treatment of highly symptomatic or hemodynamically compromised patients. Hybrid therapy and the "pill in the pocket"-strategy seem to be potent new therapeutic options.

Anti-Arrhythmia Agents↗
PubMed2005

[Quality of life following percutaneous coronary interventions in octogenarians].

BACKGROUND: Percutaneous coronary interventions (PCI) are increasingly performed in elderly patients. However, it is not known whether PCI leads to symptomatic relief comparable to that in younger patients. PATIENTS AND METHODS: 55 Patients aged 80 years or above with stable angina (82 +/- 2 years, 33 males, 22 females) were prospectively compared with younger patients (62 +/- 8 years) regarding their quality of life following PCI. For psychometric evaluation, the German version of the SF-36 Health Survey was used. RESULTS: Prior to angioplasty, there was significant physical pain, a perception of reduced general health and a significant limitation of physical activity in both groups. The number of diseased vessels was 2.7 +/- 0.6 in octogenarian patients vs. 2.6 +/- 0.7 in control patients; interventions were performed in 1.1 +/- 0.3 vs. 1.0 +/- 0.2 vessels and in 1.3 +/- 0.7 vs. 1.3 +/- 0.5 lesions. Frequency of stent implantation was 0.9 +/- 0.3 per lesion in both groups. Success rates were comparable in both groups (94 % vs. 97 %), as well as complication rates In both groups 6 months after angioplasty, bodily pain had decreased, the perception of general health and the ability to fulfill physical role expectations had improved. The effects on bodily pain and on the ability to fulfill physical role expectations were more pronounced in octogenarian patients. CONCLUSIONS: Our study shows that PCI improves quality of life in octogenarian patients with stable angina without excessive risk. The benefits of PCI were, in some aspects, even more pronounced than in younger patients.

Activities of Daily Living↗
PubMed2005

Coronary artery anomalies Part II: recent insights from clinical investigations.

Congenital anomalies of the coronary arteries occur in 0.2-1.2% of the general population; they cause 12% of sports-related sudden cardiac deaths and 1.2% of non-sports-related deaths. We review some of the substantial advances that have been made both, in the understanding of the embryonic development of the coronary arteries and in the clinical diagnosis and management of their anomalies. In this second part of our review we elucidate recent approaches to defining coronary anomalies and provide information on their incidence and prognosis. In addition, we discuss the options for screening large populations for potentially lethal coronary malformations and elucidate the role of invasive diagnostic modalities such as intravascular ultrasound, flow wire and pressure wire. The clinical relevance of coronary anomalies is discussed particularly for the ill-defined group of anomalies that only occasionally cause severe clinical events comprising anomalous origination of a coronary artery from the opposite sinus (ACAOS), coronary artery fistulae and myocardial bridging. Finally, we provide an update on current diagnostic and therapeutic recommendations.

Arrhythmias, Cardiac↗
PubMed2005

Radiofrequency catheter ablation of two accessory pathways with different unidirectional conduction properties.

Simultaneous occurrence of narrow and broad QRS complex tachycardias in patients with WPW syndrome usually indicates a macroreentry in an orthodromic atrioventricular reentry-tachycardia using the AV node as antegrade and the accessory pathway as retrograde conduction and vice versa in an antidromic circuit. We report on a 32-year-old woman with WPW syndrome presenting with both a narrow and a broad QRS complex tachycardia using two accessory pathways with different unidirectional conduction properties in combination of an exclusively antegrade conducting AV node. This case report describes conventional mapping techniques and ablation of this unusual entity of a WPW syndrome.

Adult↗
PubMed2005

[Prevention of coronary heart disease: smoking].

Smoking is the leading preventable cause of illness and premature death in Germany, claiming over 110,000 lives a year because it directly increases the risk of dying from heart disease, stroke, emphysema and a variety of cancers. The overwhelming majority of smokers begin tobacco use before they reach adulthood. Among those young people who smoke, the average age is now 13-14. In Germany, about 39% of male and 31% of female adults (age 18-60 years) continue to smoke, despite information about the unequivocally negative health consequences of smoking. The exact mechanisms of smoking-related vascular disease are not yet known. Smoking causes acute hemodynamic alterations such as increase in heart rate, systematic and coronary vascular resistance, myocardial contractility, and myocardial oxygen demand. These short-term effects could lower the ischemic threshold in smokers with coronary artery disease and contribute to the increased risk for acute cardiovascular events. Endothelial damage is thought to be an initiating event in atherosclerosis and early studies have demonstrated that long-term smoking has direct toxic effects with structural changes of human endothelial cells. Recent research has shown the importance of the functional role of the endothelium in regulating vascular tone, platelet-endothelial interactions, leukocyte adhesion and smooth muscle cell proliferation via synthesis and release of a variety of substances such as nitric oxide. There is strong evidence that smoking leads to endothelial dysfunction mainly by increased inactivation of nitric oxide by oxygen-derived free radicals. Smoking also increases oxidative modification of LDL and is associated with lower HDL plasma levels. Smoking induces a systemic inflammatory response with increased leukocyte count and elevation of the C-reactive protein level. Importantly, the prothrombotic effects of smoking have been repeatedly demonstrated to cause alterations in platelet function, imbalance of antithrombotic vs prothrombotic factors, and decrease of fibrinolytic activity. Given the enormous health hazard of tobacco use, complete abstinence from smoking should be achieved. Smoking cessation counselling should be given to healthy subjects and even more vigorously to patients with manifested disease. Every effort should be undertaken to prevent children and adolescents from starting to smoke. Brief tobacco dependence treatment is effective, and every smoker should be offered at least brief treatment at every office visit. More intensive treatment is more effective in producing long-term abstinence from tobacco. Nicotine replacement therapy (nicotine patches or gum), clinician-delivered social support, and skills training are the three most effective components of smoking cessation treatment. A framework for tobacco control measures is necessary to reduce tobacco consumption and exposure to tobacco smoke. Recommendations on specific tobacco control interventions are: 1. increase in tobacco taxes; 2. comprehensive tobacco advertising bans; 3. legislation prohibiting smoking in work and public places; 4. prohibiting the sales of tobacco products to persons under 18; 5. comprehensive disclosure of the physical, chemical and design characteristics of all tobacco products; 6. training of health professionals to promote smoking prevention and cessation interventions; and 7. development of a national network of smoking cessation treatment services.

Age Distribution↗
PubMed2005

[Calcium scoring and coronary angiography performed with multislice spiral CT -- clinical experience].

PURPOSE: To report our clinical experience in calcium scoring and coronary angiography with multislice computer tomography (MSCT). MATERIAL AND METHODS: Cardiac four-row MSCT (Siemens, Volume Zoom, Erlangen, Germany) was performed in 60 patients, comprising 45 patients without known coronary vessel disease (CVD) and falling in an intermediate risk (group I) by calcium scoring, and 15 patients with multivessel disease by the combination of calcium scoring and MSCT coronary angiography (group II). Group I underwent analysis of risk factors as well as patient management in the form of risk profile modulation, indication for invasive selective coronary angiography (SCA) and supplemental myocardial diagnostic evaluation (e. g., SPECT). Agatston and volume scores (Virtuoso, Siemens, Erlangen, Germany) were calculated for calcium scoring. Group II had the calcium scoring and diagnostic accuracy of MSCT in detecting coronary artery stenosis evaluated according to established American Heart Association (AHA) criteria. SCA was used as gold standard. RESULTS: In group I, calcium scoring was positive in 27/45 (60 %) patients, with 14/27 (52 %) consecutively referred to SCA and 2/27 (7 %) to SPECT. SCA revealed significant coronary stenosis (> 60 %) in 5/27 (19 %) patients and SPECT detected myocardial ischemia in 0/2 patients. Patients with obstructive coronary vessel disease showed a significantly increased calcium score of > 300 together with a high risk profile. Patients with negative calcium score showed significantly less risk factors (p < 0.05). The use of calcium scoring in therapeutic procedures in the form of increased modulation of risk factors was documented in 21/45 (47 %) patients. In group II, sensitivity, specificity and diagnostic accuracy for the detection of high grade coronary artery stenosis were 64 %, 99 % and 96 %, and the Agatston and Volume scores were 333 +/- 123 and 334 +/- 136, respectively. CONCLUSION: MSCT can be applied as risk profile module for coronary screening of patients with intermediate risk. As non-invasive alternative for the evaluation of coronary vessel disease, it can be useful in some cases by providing additional information.

Adult↗
PubMed2004

Coronary artery anomalies. Part I: Recent insights from molecular embryology.

Congenital anomalies of the coronary arteries occur in 0.2-1.2% of the general population and may cause substantial cardiovascular morbidity and mortality. We review some of the advances that have been made both, in the understanding of the embryonic development of the coronary arteries (part I) and in the clinical diagnosis and management of their anomalies (part II). In this first part of our review we elucidate basic mechanisms of coronary vasculogenesis, angiogenesis and embryonic arteriogenesis. Moreover, we review the role of cellular progenitors such as epicardium-derived cells, cardiac neural crest cells and cells of the peripheral conduction system. Then we discuss the role of growths factors (such as FGV, HIF 1, PDGF B, TGFbeta1, VEGF, and VEGFR-2) and genes (such as FOG-2, VCAM-1, Bves, and RALDH2) at different states of coronary development. and we discuss the role of the cardiac neural crest in the concurrence of coronary anomalies with aortic root malformations. This part of the article is designed to review major determinants of coronary vascular development to provide a better understanding of the multiplicity of options and mechanisms that may give rise to coronary anomaly. To this end, we highlight results from experiments that provide insight in mechanisms of coronary malformation.

Animals↗
PubMed2004

Prognostic significance of the signal averaged electrocardiogram in patients with chronic stable coronary artery disease. Analysis in the time domain and by spectral temporal mapping.

BACKGROUND: Ventricular late potentials detected by the signal averaged electrocardiogram (SAECG) have been used to predict cardiac death in patients after recent myocardial infarction. The goal of this study was to investigate the prognostic significance of the SAECG in a population of chronic coronary artery disease, with and without previous myocardial infarction. METHODS: SAECG was recorded in 698 patients with angiographically proven coronary artery disease and analyzed by time domain analysis (TDA) and by spectral temporal mapping (STM). Cardiac death or ventricular fibrillation (= cardiac event) were used as the primary endpoint for follow-up (25 to 33 months). RESULTS: A cardiac event occurred in 46 out of 698 patients (6.6%). An abnormal SAECG using TDA was found in 43% of patients with a cardiac event, as compared to 21.7% in those without (p<0.0005). The probability of a cardiac event during follow-up was 4.4% when TDA and STM were both normal, 9.5% and 10.2% when either STM or TDA were abnormal and 28.5% when both were abnormal. A duration of the averaged QRS complex of more than 120 ms and a left ventricular ejection fraction of less than 45% were the only independent predictors of a cardiac event. Logistic regression analysis could predict a cardiac event with a sensitivity of 54% and a specificity of 88%. CONCLUSIONS: In patients with chronic coronary artery disease the duration of the signal averaged QRS complex and left ventricular ejection fraction are independent predictors of cardiac death or ventricular fibrillation.

Adult↗