RESUMEN
Radiofrequency (RF) ablation requires a complex set of devices as well as profound electrophysiological experience and substantial knowledge of physical science basics. To establish RF ablation in-vitro teaching-system, six workstations were equipped with computer-controlled RF ablation generators. Universal connection boxes allow ablation-essays with catheters of different make and model. Special wetlabs were developed combining a basin containing isotonic saline solution with a thermostat and a pump to simulate blood flow. This hands-on teaching system can be used to demonstrate differences in lesion-forming dependent on tip-electrodes, sensor technology and ablation techniques, influence of blood flow and electrode-angle to the myocardium. It was also utilized to reproduce industrial in-vitro tests.
RESUMEN
AIMS: Coronary artery disease in young adults is important task of contemporary cardiology. Presented our results experience and opinion were obtained by our long term investigation of myocardial infarction in young patients under 40 years. METHODS: Two sets of patients were examined - 78 patients (74 men, 4 women) hospitalised in pretrombolytic era in prospective 8 years follow up (1984-1992) and 39 patients (35 men, 4 women) admitted during period 2000-2010 analysed retrospective. RESULTS: Myocardial infarction in young age belongs roughly to two different groups with considerable overlap in pathogenetic mechanisms: 1. angiographycally normal coronary arteries or unilocular nonsignificant atherosclerotic stenosis (less 50%) in 25-30% with thrombotic occlusion of one infarct related artery probably with substantial vasospastic component. Patients were younger (average 31.7 ± 3.7 years), dominant risk factors smoking, hyperlipidemia, excessive physical and emotional stress. Disease course and prognosis are favourable. 2. premature accelerated atherosclerosis with significant (more 50%) in 70-75 % often multivessel affection. Pts were significantly older (average 35.8 ± 2.6 years; < 0.001) bad risk factors profile, worse clinical course and poor long-term prognosis. CONCLUSIONS: Study of myocardial infarction in young adults indicates: great role of risk factors, mainly smoking, hyperlipidemia, family history and type A behaviour, hostility with participation of low education level and social inequality (unemployment). Noticeable are hypercoagulable states and trauma. Dominancy of men (90-95%). Prognosis depends on age, extend of coronary atherosclerosis and residual cardiac function. Disease picture has not been changed during last 30 years. Aggressive control over risk factors is unavoidable. Current requirement is to evaluate impact of modern treatment strategy on long-term survival. Key words: coronary artery disease - myocardial infarction at young age.
Asunto(s)
Enfermedad de la Arteria Coronaria/diagnóstico , Infarto del Miocardio/diagnóstico , Adulto , Factores de Edad , Angiografía Coronaria , Enfermedad de la Arteria Coronaria/complicaciones , Femenino , Estudios de Seguimiento , Humanos , Masculino , Infarto del Miocardio/complicaciones , Pronóstico , Factores de RiesgoRESUMEN
BACKGROUND: Each and every hospital of any kind is forced, due to increased cost pressure, to work as economically and as efficiently as possible. This even applies when the operational orientations of the hospitals institutions are different. In the present article an analysis of the repercussions of the treatment of postoperative complications in terms of entrepreneurial practice is given. Our focus is on the opportunity cost. METHOD: A theoretical calculation of opportunity costs is made based on the example of postoperative infections following cardiac surgery and the resulting treatment. The bases of the examinations are the results collected at the hospital Mediclin Herzentrum Lahrâ/âBaden in 2008. The wound healing disorders were recorded from November 2004 until November 2007 and include 3675âpatients who were operated on using a median sternotomy. Out of the 3675âpatients 45 (1.2 %) were affected. Various treatment options are at hand. The used therapy algorithm in our practice is dependent on the stage and the development of the infection. RESULTS: If the high trim point, the medial trim point and the low trim point of the mediastinitis patients, as well as the average revenue and the surcharge omission on exceeding the high trim point (these data can be found in the annual accounts) and knowledge of the actual length of stay of the mediastinitis patient are known, the opportunity cost, respectively potential turnover increases, can be calculated. Reducing the medial trim point from 48.43 to, for example, 36.37âdays could potentially produce a turnover increase of as much as 10â633.41â. CONCLUSION: Keeping patient safety in mind, significant turnover increases can be achieved with adequate planning. The considered sales situation, however, can only be achieved under the same terms: these being free operating room and bed capacities, available personnel, equal cost of materials as well as enough patients. The consideration of opportunity costs could be important for entrepreneurs if staff shortage continues and, in economical terms, non-expendable capacities are created.
Asunto(s)
Análisis Costo-Beneficio , Cardiopatías/economía , Cardiopatías/cirugía , Costos de Hospital/estadística & datos numéricos , Mediastinitis/economía , Complicaciones Posoperatorias/economía , Esternotomía/economía , Infección de la Herida Quirúrgica/economía , Grupos Diagnósticos Relacionados/economía , Emprendimiento/economía , Femenino , Alemania , Humanos , Tiempo de Internación/economía , Masculino , Mediastinitis/cirugía , Modelos Económicos , Programas Nacionales de Salud/economía , Planificación de Atención al Paciente/economía , Complicaciones Posoperatorias/cirugía , Mecanismo de Reembolso/economía , Infección de la Herida Quirúrgica/cirugíaRESUMEN
The German National Institute for Quality in Healthcare has also developed a program of external quality assessment in the field of cardiology. Hospitals are committed to collect certain data of diagnostic coronary angiography, percutaneous coronary interventions and pacemaker implantations. If statistical abnormalities are observed a so called structured dialogue is implemented. The responsible physicians of the hospitals are asked to comment possible quality deficits. Appointed members of quality commissions examine the answers and can invite the responsible physicians for interviews or also visit the hospital. However the validity of the quality data is problematic, because audits or check-ups of quality assessment in place are lacking. Therefore the results should not be misused for a comparison or ranking of hospitals with each other. As long as the validity of the quality assessment has not been improved, the results should also not be accessible for other parties, such as health insurances.
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Cardiología/normas , Garantía de la Calidad de Atención de Salud , Academias e Institutos/normas , Angioplastia Coronaria con Balón/normas , Alemania , Hospitales/normas , Humanos , Marcapaso Artificial/normasRESUMEN
Patients with aortocoronary bypass surgery generally have a severe, advanced coronary atherosclerosis. An intensive risk-factor management should be of special importance in these patients. However, cholesterol treatment goals are the same for operated or non-operated patients with coronary artery disease. Effective cholesterol lowering does not only decrease the progression of atherosclerosis in native coronary vessels but also helps to prevent the development of atherosclerosis in venous bypass grafts. Clinical studies demonstrated that this leads to an improvement of clinical endpoints. Unfortunately we know from registries, that even in bypass patients recommended guidelines for cholesterol lowering are often not followed.
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Anticolesterolemiantes/uso terapéutico , Puente de Arteria Coronaria , Hipercolesterolemia/tratamiento farmacológico , Aterosclerosis/tratamiento farmacológico , Aterosclerosis/prevención & control , Aterosclerosis/cirugía , Colesterol/sangre , Vasos Coronarios/efectos de los fármacos , Vasos Coronarios/patología , Adhesión a Directriz , Humanos , Hipercolesterolemia/complicaciones , Guías de Práctica Clínica como Asunto , Factores de RiesgoRESUMEN
Two methods for the determination of I- in raw and processed milk were examined. A simple ion-specific electrode (ISE) method was compared against a more complex HPLC reference technique. Accuracy and precision were evaluated both within and between the 2 methods. Both methods yielded good recoveries for Ion spiked samples, ranging from 87 to 114% for ISE and 91 to 100% for HPLC. Within-run repeatability and between-run reproducibility were superior with the HPLC method, but were still more than acceptable with the ISE technique. Overall agreement of paired results between ISE and HPLC methods was good (r2 = 0.85 on raw herd milk; r2 = 0.84 on processed milk). The ISE method had a significant positive bias relative to the HPLC reference method. Both methods lend themselves well to the measurement of I- in raw or processed milk. Given its relatively low cost and ease of use, the ISE method is well suited as a screening method. The impressive accuracy, precision, selectivity, and limit of detection of the HPLC technique make it an ideal confirmation method.
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Cromatografía Líquida de Alta Presión/métodos , Yoduros/análisis , Electrodos de Iones Selectos , Leche/química , Animales , Manipulación de Alimentos , Reproducibilidad de los Resultados , Sensibilidad y EspecificidadRESUMEN
The article describes the exposure pathways of cadmium in the Czech urban population. The data on Cd concentrations originated from the Environmental Health Monitoring System, which has been realized in 30 cities since 1994. The data on cadmium content in particular exposure pathways - diet, drinking water, ambient air and soil -were processed for the period 1994-2003. The estimate of the daily dietary intake for an average adult population amounted to 11-19 microg/d, i.e. 0.17-0.30 microg/kg bw/d, which represents 17%-30% of the PTWI (provisional tolerable weekly intake). The contribution from drinking water to the oral exposure is low; on average 0.5 microg/d. Potential exposure to airborne Cd was estimated at about 0.02 microg/d. The additional Cd intake from urban soil ingestion probable in small children was found to be insignificant based on Cd concentrations in the soil of kindergarten playgrounds. Biomonitoring outputs characterize the recent and life-long cadmium burden of the Czech population from general environment In 1994-2003, the median blood Cd levels ranged in the interval 0.9-0.4 microg/l blood, in smokers being more than double that in non-smokers. Blood Cd levels detected indicate slightly decreasing trend as well as urine Cd levels (range of median values 0.44-0.28 microg/g creatinine). Since 1996 the levels in children have been found in more than 50% cases below the detection limit of the methods used. The estimated total cadmium intake in the Czech urban population does not signalize any increased risk of health impairment considering non-carcinogenic effects.
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Cadmio/toxicidad , Exposición a Riesgos Ambientales , Población Urbana , Líquidos Corporales/química , Cadmio/análisis , Preescolar , República Checa , Monitoreo del Ambiente , Análisis de los Alimentos , Humanos , Exposición por Inhalación , Control de Calidad , Contaminantes del Suelo/análisis , Espectrofotometría Atómica , Abastecimiento de Agua/análisisRESUMEN
Carvedilol, a nonselective beta 1-, beta 2-adrenoreceptor blocking agent with alpha 1-adrenoreceptor blocking activity, is often prescribed as an adjunctive pharmacological therapy in patients who received an ICD. Despite the new ICD technology, concomitant antiarrhythmic therapy still represents the most important concern in patients with an ICD. As illustrated by this case, carvedilol may also increase the energy requirement for internal defibrillation.
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Carbazoles/efectos adversos , Desfibriladores Implantables , Propanolaminas/efectos adversos , Taquicardia Ventricular/terapia , Anciano , Carbazoles/administración & dosificación , Carvedilol , Terapia Combinada , Capacidad Eléctrica , Humanos , Masculino , Propanolaminas/administración & dosificación , Taquicardia Ventricular/etiologíaRESUMEN
The paper presents the results of geochemical investigations carried out in the city of Prague. Czech Republic, between the years 1994-1997, by the Czech Geological Institute, National Institute of Public Health and Hygiene Stations of Prague. Exposure assessment for children as the most sensitive population, based on soil ingestion pathway, indicates that lead is the major pollutant of concern, especially in the central regions of the city. Direct exposure assessment was done by analyzing blood and urine samples collected from children aged 3-6 years. Blood lead levels were the only biomarker significantly higher as compared to the control group (32.1 +/- 17.4 microg/l, 25.1 +/- 15.4 microg/l). This pilot study supports the establishment of a new sub-system within the already existing System of Monitoring the Environmental Impact on Population Health of the Czech Republic.
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Exposición a Riesgos Ambientales/efectos adversos , Monitoreo del Ambiente/métodos , Metales Pesados/efectos adversos , Suelo/análisis , Adolescente , Adulto , Niño , Preescolar , República Checa , Femenino , Estado de Salud , Humanos , Masculino , Metales Pesados/análisis , Persona de Mediana Edad , Proyectos Piloto , Medición de Riesgo , Muestreo , Sensibilidad y Especificidad , Población UrbanaRESUMEN
Experimental and clinical data suggests that almost all Class III antiarrhythmic agents diminish their ability to prolong cardiac repolarization at fast heart rates. However, only limited data exists about the time course of efficacy decay of Class III agents after sudden increase of the heart rate. In the present study, we assessed both rate and time dependent changes of the efficacy of d-sotalol in higher stimulation frequencies following an abrupt increase in heart rate. This might imitate the situation seen in the development of paroxysmal tachycardias. Monophasic action potentials were recorded from the right ventricular apex during sinus rhythm and constant stimulation with the paced cycle length (PCL) of 550 ms, 400 ms, and 330 ms in the baseline and 20 minutes after intravenous administration of d-sotalol (2.5 mg/kg) in seven patients with documented life-threatening ventricular tachyarrhythmias. D-sotalol significantly prolonged monophasic action potential duration at different steady-state heart rates (sinus rhythm: 21.1% +/- 3.6%; PCL 550 ms: 16.6% +/- 4.3%, 400 ms: 11.2% +/- 2.7%, 330 ms: 5.8% +/- 2.1%). The prolongation is significantly shorter in higher steady-state pacing, confirming a pronounced reverse-use dependent decrease of the efficacy of d-sotalol at faster stimulation frequencies. After the abrupt increase in heart rate, the beat-to-beat adaptation of the postdrug action potential prolongation exhibits only slight reverse-use dependent shortening. The decrease of the efficacy of d-sotalol is insignificant for the first 20 consecutive beats at the stimulation frequency of the PCL of 400 msec (from 16.6% at PCL of 550 ms to 14.6% at the 20th beat of the PCL of 400 ms), and for the first ten consecutive beats at the stimulation frequency of the PCL of 330 ms (from 16.8% at PCL of 550 ms to 12.3% at the 10th beat of the PCL of 330 ms). This slow decay of action potential prolongation after an abrupt increase in heart rate might contribute to the antiarrhythmic action of d-sotalol in cardiac tachyarrhythmias.
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Potenciales de Acción/efectos de los fármacos , Antiarrítmicos/farmacología , Corazón/fisiopatología , Sotalol/farmacología , Taquicardia Ventricular/fisiopatología , Anciano , Estimulación Cardíaca Artificial , Electrofisiología , Frecuencia Cardíaca , Humanos , Masculino , Persona de Mediana EdadRESUMEN
Of the traditional antiarrhythmic agents administered in the treatment of ventricular tachycardias, those belonging to Class III are most commonly used. However, some ventricular tachycardias displaying special clinical, electrocardiographic and/or electrophysiologic characteristics have been successfully treated with calcium antagonists. Otherwise, Class IV antiarrhythmic agents are primarily used in the treatment of supraventricular tachyarrhythmias. It is reasonable to suspect that calcium-dependent phenomena underlie ventricular tachyarrhythmias in a number of patients. Verapamil-sensitive sustained left ventricular tachycardias represent a typical example. Sufficient response to calcium antagonists has also been demonstrated for exercise-induced ventricular tachycardias and repetitive monomorphic ventricular tachycardias. Characteristically, these arrhythmias occur in young patients with no structural heart disease. The long-term prognosis of these patients is in fact very good, but because of intrusive symptoms, pharmacological or nonpharmacological (radiofrequency ablation) treatment is often indicated. Through correct diagnosis and implementation of a short- and long-term therapy with calcium antagonists, and excellent alternative to the potentially harmful therapy with Class I and Class III antiarrhythmic agents can be offered.
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Antiarrítmicos/uso terapéutico , Bloqueadores de los Canales de Calcio/uso terapéutico , Electrocardiografía/efectos de los fármacos , Taquicardia Ventricular/tratamiento farmacológico , Antiarrítmicos/efectos adversos , Calcio/fisiología , Bloqueadores de los Canales de Calcio/efectos adversos , Ensayos Clínicos como Asunto , Prueba de Esfuerzo/efectos de los fármacos , Humanos , Taquicardia Ventricular/fisiopatologíaRESUMEN
Transesophageal phase images and precordial electrocardiography (ECG) were used to localize accessory pathways during adenosine-induced preexcitation in 30 patients (18 men, mean age +/- SD 33 +/- 14 years) undergoing endocardial mapping for suspected Wolff-Parkinson-White syndrome. Digitized 2-dimensional echocardiographic cine loops were mathematically transformed using a first harmonic Fourier algorithm before and after catheter ablation. Endocardial mapping found single accessory pathways with anterograde conduction in 20 patients, concealed pathways in 7, and atrioventricular reentry circuits in 3 patients. At baseline, precordial ECG correctly localized 8 pathways (40%) with anterograde conduction and predicted 5 adjacent locations (25%), but findings were normal in 7 patients (35%). Phase imaging correctly identified only 3 pathway locations (15%), findings were normal in 15 (75%), and could not be obtained in 2 patients (10%). Adenosine augmented manifest but minimal preexcitation in 9 patients and unmasked latent preexcitation in 7. In 4 patients, preexcitation was already maximal at baseline. During adenosine-augmented preexcitation, ECG correctly identified 13 locations (65%), but still predicted 7 adjacent locations (35%). However, phase imaging correctly identified 15 locations (75%) and predicted only 3 adjacent locations (15%). All midseptal (n = 2) and anteroseptal (n = 2) locations were correctly identified by phase imaging, but none by ECG. On follow-up studies in 16 patients, successful catheter ablation (n = 13) was equally well confirmed by ECG and phase imaging. Therefore, transesophageal echocardiographic phase imaging during adenosine-induced preexcitation is a readily available and safe procedure that appears clinically most useful for identifying septal pathways.
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Adenosina/farmacología , Ecocardiografía Transesofágica , Sistema de Conducción Cardíaco/fisiopatología , Síndrome de Wolff-Parkinson-White/fisiopatología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Factores de Confusión Epidemiológicos , Electrocardiografía , Femenino , Sistema de Conducción Cardíaco/efectos de los fármacos , Humanos , Masculino , Persona de Mediana Edad , Síndrome de Wolff-Parkinson-White/diagnóstico por imagenRESUMEN
The implantable cardioverter/defibrillator is gaining increasing significance in the therapy of life-threatening ventricular arrhythmias. Independently, the team of Mirowski and the team of Schuder started to develop experimental automatic implantable defibrillators in the seventies. In 1980, the first human implant of an automatic defibrillator was done by Levi Watkins together with the team of Mirowski in Baltimore, USA. Since 1989 implantable cardioverter/defibrillators exhibit multiple functions among which are high energy defibrillation therapy, low energy cardioversion, antitachycardia pacing, permanent and post therapy antibradycardia pacing, diagnostic counters, and device status parameters. This offers a markedly improved technical device to the patients. Evaluation of the patient's diagnostic counters provide a detailed overview about the patient's arrhythmia history and information for optimizing antitachycardia pacing therapy and additional antiarrhythmic drug therapy. The availability of non-thoractomy transvenous lead systems and biphasic shock forms allows the insertion of the device without open chest surgery and even without subcutaneous leads resulting in low mortality rates and an exclusively transvenous system. Single-lead unipolar devices are currently investigated in clinical trials. Future development of atrial sensing lead systems may further reduce inappropriate shock therapy triggered by sinus tachycardia or atrial tachyarrhythmias, e.g. atrial fibrillation, and may be used for dual chamber stimulation. Hemodynamic sensors for determining the severity of the arrhythmia are currently under experimental evaluation. Possible prognostic indications of ICD therapy in patients without a history of malignant arrhythmias are currently studied in several prospective trials. All new directions hold promise to expand and improve the use of ICDs in patients at risk for sudden cardiac death.
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Desfibriladores Implantables/tendencias , Taquicardia Ventricular/terapia , Muerte Súbita Cardíaca/prevención & control , Diseño de Equipo , Falla de Equipo , Predicción , Humanos , Tasa de Supervivencia , Taquicardia Ventricular/mortalidadRESUMEN
The complexity of newer implantable defibrillators has made device follow-up increasingly more intricate. Extensive data-logging capacity provides specific information on recorded events, which facilitates more accurate determination of patient arrhythmias. This helps the clinician judge whether the device is detecting and treating arrhythmias appropriately, or whether false sensing of external signals or supraventricular rhythms is occurring. There is also a record of the efficacy of delivered therapy from the device that helps in optimizing subsequent programming. Programming itself has become much more complicated, with multiple independently programmable therapy zones, each with numerous available therapeutic modalities. In addition, defibrillator status information has been improved. Accurate battery voltage measurements give a reasonable estimate of remaining device life, and pace/sense and shock lead impedances can be measured to provide information on total system integrity. Together, these advances allow more specific programming of the device to the individual patient's condition but require increasing experience and expertise of the physician.
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Desfibriladores Implantables , Desfibriladores Implantables/tendencias , Electrodos Implantados , Diseño de Equipo , Falla de Equipo , Humanos , Marcapaso Artificial , Programas Informáticos , Taquicardia Ventricular/terapia , TelemetríaRESUMEN
Eighty-six patients were treated with an implantable cardioverter defibrillator (ICD) because of sustained ventricular tachycardia (VT) or ventricular fibrillation (VF). In 27 patients an epicardial system was used, in 59 patients a transvenous system with a subcutaneous patch electrode was implanted. During a mean follow-up time of 17 +/- 9 months, inappropriate activations of the ICD due to supraventricular tachycardia were documented by Holter monitoring in 14 patients (16%). In 8 patients paroxysmal atrial fibrillation (AF), in 2 patients chronic AF, in 1 patient atrial flutter, and in 3 patients sinus tachycardia triggered antitachycardia pacing functions (12 patients) or internal defibrillation (2 patients). In 3 patients (5%) VT was induced by inappropriate antitachycardia pacing. In an additional 18 patients (21%) inappropriate activation of antitachycardia functions due to atrial tachyarrhythmias were suspected based on telemetry readouts or the patient's history. Inappropriate activation of ICD therapy triggered by intermittent supraventricular tachyarrhythmias is common. Further improvements of detection algorithms for supraventricular tachycardia are required in future device generations.
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Desfibriladores Implantables , Marcapaso Artificial , Taquicardia Supraventricular/fisiopatología , Amiodarona/uso terapéutico , Fibrilación Atrial/fisiopatología , Fibrilación Atrial/terapia , Quimioterapia Adyuvante , Electrocardiografía , Electrocardiografía Ambulatoria , Diseño de Equipo , Falla de Equipo , Prueba de Esfuerzo , Femenino , Estudios de Seguimiento , Frecuencia Cardíaca/fisiología , Humanos , Masculino , Persona de Mediana Edad , Tasa de Supervivencia , Taquicardia Paroxística/fisiopatología , Taquicardia Paroxística/terapia , Taquicardia Supraventricular/tratamiento farmacológico , Taquicardia Supraventricular/terapia , Taquicardia Ventricular/tratamiento farmacológico , Taquicardia Ventricular/fisiopatología , Taquicardia Ventricular/terapia , Fibrilación Ventricular/tratamiento farmacológico , Fibrilación Ventricular/fisiopatología , Fibrilación Ventricular/terapiaRESUMEN
The authors present the case-history of a 15-year-old sportsman with acute "non Q" myocardial infarction. The disease is associated with excessive physical strain and subsequent protracted paroxysm of supraventricular tachycardia with severe hypotension. The paper is supplemented by ECG tracings and laboratory findings, echocardiographic, scintigraphic, coronarographic and other examinations. Pathological changes of the coronary arteries, or preexisting metabolic disease or myocardial disease, valvular defects or congenital anomalies were not confirmed. The authors draw attention to the possible occurrence of myocardial infarction also in very young subjects as a result of excessive physical strain along with other possible pathogenetic mechanisms.
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Infarto del Miocardio , Adolescente , Electrocardiografía , Ejercicio Físico , Humanos , Masculino , Infarto del Miocardio/etiología , Infarto del Miocardio/fisiopatología , Taquicardia Supraventricular/etiología , Taquicardia Supraventricular/fisiopatologíaRESUMEN
In a group of 25 men after myocardial infarction (MI) at an age under 40 years the occurrence of risk factors of ischaemic heart disease, the results of both invasive and noninvasive investigations as well as other special examinations within one year after the attack of acute MI were analysed. In 36% there was a normal finding or nonsignificant stenosis on the coronary arteries (less than 50% lumen obstruction at coronary angiography); a significant stenosis was found in 64%, out of which only one coronary vessel was affected in 32%. Dominant risk factors were: smoking, lipid metabolism disturbances, hypertension and a positive family history. The average number of risk factors in the group with a normal finding on the coronary arteries was 2.55, and in the group with a significant coronary sclerosis 4.85. The risk of myocardial infarction is increased by the coexistence of heavy smoking habits and vigorous physical activity. No correlation was found between the extent and location of coronary sclerosis and the functional parametres and wall motion of the left ventricle. An analysis of occupational status before MI revealed that 52% of the patients were workers, 40% professional drivers and only 8% were clerks.