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1.
Circulation ; 100(17): 1791-7, 1999 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-10534466

RESUMO

BACKGROUND: Interaction between wave fronts in the right and left atrium may be important for maintenance of atrial fibrillation, but little is known about electrophysiological properties and preferential routes of transseptal conduction. METHODS AND RESULTS: Eighteen patients (age 44+/-12 years) without structural heart disease underwent right atrial electroanatomic mapping during pacing from the distal coronary sinus (CS) or the posterior left atrium. During distal CS pacing, 9 patients demonstrated a single transseptal breakthrough near the CS os, 1 patient in the high right atrium near the presumed insertion of Bachmann's bundle and 1 patient near the fossa ovalis. The mean activation time from stimulus to CS os was 48+/-15 ms compared with 86+/-15 ms to Bachmann's bundle insertion (P<0.01) and 59+/-23 ms to the fossa ovalis (P=NS and P<0.01, respectively). During left atrial pacing, the earliest right atrial activation was near Bachmann's bundle in 5 and near the fossa ovalis in 4 patients. The activation time from stimulus to CS os was 70+/-15 ms compared with 47+/-16 ms to Bachmann's bundle (P<0.01) and 59+/-25 ms to the fossa ovalis (P=NS). Whereas the total septal activation time was not significantly different during CS pacing compared with left atrial pacing (41+/-16 versus 33+/-17 ms), the total right atrial activation time was longer during CS pacing (117+/-49 versus 79+/-15 ms; P<0.05). CONCLUSIONS: Three distinct sites of early right atrial activation may be demonstrated during left atrial pacing. These sites are in accord with anatomic muscle bundles and may have relevance for maintenance of atrial flutter or fibrillation.


Assuntos
Função Atrial , Mapeamento Potencial de Superfície Corporal/métodos , Sistema de Condução Cardíaco/fisiologia , Adulto , Condutividade Elétrica , Eletrofisiologia , Feminino , Humanos
2.
J Am Coll Cardiol ; 35(5): 1276-87, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10758970

RESUMO

OBJECTIVES: This study was directed at developing spatial 62-lead electrocardiogram (ECG) criteria for classification of counterclockwise (CCW) and clockwise (CW) typical atrial flutter (Fl) in patients with and without structural heart disease. BACKGROUND: Electrocardiographic classification of CCW and CW typical atrial Fl is frequently hampered by inaccurate and inconclusive scalar waveform analysis of the 12-lead ECG. METHODS: Electrocardiogram signals from 62 torso sites and multisite endocardial recordings were obtained during CCW typical atrial Fl (12 patients), CW typical Fl (3 patients), both forms of typical Fl (4 patients) and CCW typical and atypical atrial Fl (1 patient). All the Fl wave episodes were divided into two or three successive time periods showing stable potential distributions from which integral maps were computed. RESULTS: The initial, intermediate and terminal CCW Fl wave map patterns coincided with: 1) caudocranial activation of the right atrial septum and proximal-to-distal coronary sinus activation, 2) craniocaudal activation of the right atrial free wall, and 3) activation of the lateral part of the subeustachian isthmus, respectively. The initial, intermediate and terminal CW Fl wave map patterns corresponded with : 1) craniocaudal right atrial septal activation, 2) activation of the subeustachian isthmus and proximal-to-distal coronary sinus activation, and 3) caudocranial right atrial free wall activation, respectively. A reference set of typical CCW and CW mean integral maps of the three successive Fl wave periods was computed after establishing a high degree of quantitative interpatient integral map pattern correspondence irrespective of the presence or absence of organic heart disease. CONCLUSIONS: The 62-lead ECG of CCW and CW typical atrial Fl in man is characterized by a stereotypical spatial voltage distribution that can be directly related to the underlying activation sequence and is highly specific to the direction of Fl wave rotation. The mean CCW and CW Fl wave integral maps present a unique reference set for improved clinical detection and classification of typical atrial Fl.


Assuntos
Flutter Atrial/classificação , Flutter Atrial/diagnóstico , Mapeamento Potencial de Superfície Corporal/métodos , Eletrocardiografia/métodos , Endocárdio , Sistema de Condução Cardíaco , Idoso , Algoritmos , Flutter Atrial/tratamento farmacológico , Flutter Atrial/etiologia , Flutter Atrial/fisiopatologia , Mapeamento Potencial de Superfície Corporal/instrumentação , Análise Discriminante , Eletrocardiografia/instrumentação , Endocárdio/fisiopatologia , Feminino , Sistema de Condução Cardíaco/fisiopatologia , Cardiopatias/complicações , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Fatores de Risco , Rotação , Sensibilidade e Especificidade , Fatores de Tempo
3.
Methods Inf Med ; 44(5): 674-86, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16400376

RESUMO

OBJECTIVE: The computer model-based computation of the cardiac activation sequence in humans has been recently subject of successful clinical validation. This method is of potential interest for guiding ablation therapy of arrhythmogenic substrates. However, computation times of almost an hour are unattractive in a clinical setting. Thus, the objective is the development of a method which performs the computation in a few minutes run time. METHODS: The computationally most expensive part is the product of the lead field matrix with a matrix containing the source pattern on the cardiac surface. The particular biophysical properties of both matrices are used for speeding up this operation by more than an order of magnitude. A conjugate gradient optimizer was developed using C++ for computing the activation map. RESULTS: The software was tested on synthetic and clinical data. The increase in speed with respect to the previously used Fortran 77 implementation was a factor of 30 at a comparable quality of the results. As an additional finding the coupled regularization strategy, originally introduced for saving computation time, also reduced the sensitivity of the method to the choice of the regularization parameter. CONCLUSIONS: As it was shown for data from a WPWpatient the developed software can deliver diagnostically valuable information at a much shorter span of time than current clinical routine methods. Its main application could be the localization of focal arrhythmogenic substrates.


Assuntos
Técnicas Eletrofisiológicas Cardíacas , Processamento de Imagem Assistida por Computador/métodos , Arritmias Cardíacas/cirurgia , Áustria , Ablação por Cateter , Simulação por Computador , Humanos , Software , Fatores de Tempo
4.
Methods Inf Med ; 44(4): 508-15, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16342917

RESUMO

OBJECTIVES: Noninvasive imaging of the cardiac activation sequence in humans could guide interventional curative treatment of cardiac arrhythmias by catheter ablation. Highly automated signal processing tools are desirable for clinical acceptance. The developed signal processing pipeline reduces user interactions to a minimum, which eases the operation by the staff in the catheter laboratory and increases the reproducibility of the results. METHODS: A previously described R-peak detector was modified for automatic detection of all possible targets (beats) using the information of all leads in the ECG map. A direct method was applied for signal classification. The algorithm was tuned for distinguishing beats with an adenosine induced AV-nodal block from baseline morphology in Wolff-Parkinson-White (WPW) patients. Furthermore, an automatic identification of the QRS-interval borders was implemented. RESULTS: The software was tested with data from eight patients having overt ventricular preexcitation. The R-peak detector captured all QRS-complexes with no false positive detection. The automatic classification was verified by demonstrating adenosine-induced prolongation of ventricular activation with statistical significance (p <0.001) in all patients. This also demonstrates the performance of the automatic detection of QRS-interval borders. Furthermore, all ectopic or paced beats were automatically separated from sinus rhythm. Computed activation maps are shown for one patient localizing the accessory pathway with an accuracy of 1 cm. CONCLUSIONS: The implemented signal processing pipeline is a powerful tool for selecting target beats for noninvasive activation imaging in WPW patients. It robustly identifies and classifies beats. The small beat to beat variations in the automatic QRS-interval detection indicate accurate identification of the time window of interest.


Assuntos
Processamento de Sinais Assistido por Computador , Software , Complexos Ventriculares Prematuros/diagnóstico , Síndrome de Wolff-Parkinson-White/diagnóstico , Potenciais de Ação , Adenosina , Adulto , Algoritmos , Ablação por Cateter , Eletrocardiografia , Eletrofisiologia , Feminino , Humanos , Modelos Anatômicos , Fatores de Tempo , Complexos Ventriculares Prematuros/cirurgia , Síndrome de Wolff-Parkinson-White/cirurgia
5.
J Heart Valve Dis ; 3(2): 185-9; discussion 190, 1994 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-8012637

RESUMO

Patients with pulmonary artery hypertension in the late course of isolated aortic stenosis are considered to have a poor prognosis. The aim of the following study was to determine the incidence of pulmonary artery hypertension, the postoperative course after valve replacement and the reversibility of pulmonary hypertension dependent on the valve prosthesis diameter. Seventy-six consecutive patients with symptomatic aortic stenosis undergoing isolated aortic valve replacement were studied. Preoperative right and retrograde left heart catheterization was performed in the cardiac catheterization laboratory. Three days after valve replacement, hemodynamic evaluation was repeated by a Swan-Gantz catheter. Patients with preoperative pulmonary hypertension (systolic pulmonary artery pressure > 30 mmHg, n = 53) differed significantly from patients without pulmonary hypertension (n = 23) with respect to systolic pulmonary pressure (52.4 +/- 17 vs. 24.3 +/- 4 mmHg), pulmonary capillary wedge pressure (22.3 +/- 10 vs. 8.8 +/- 2, p < 0.001), left ventricular end diastolic pressure (29.6 +/- 13 vs. 21.4 +/- 11) and valve area (0.64 +/- 0.10 vs. 0.79 +/- 0.11 cm2, p < 0.05). No difference was found with respect to age, maximum systolic transvalvular aortic gradient or cardiac output. Following valve replacement, the two groups did not differ significantly in fatal (2/53 vs. 1/23 or non-fatal (14/53 vs. 5/23) complications. In patients with pulmonary hypertension, systolic pulmonary pressure decreased from 52.4 +/- 17 to 38.9 +/- 6, diastolic pressure from 24.7 +/- 9 to 12.6 +/- 3, pulmonary capillary wedge pressure from 22.3 +/- 10 to 12.1 +/- 3, pulmonary capillary wedge pressure from 22.3 +/- 10 to 12.1 +/- 3 mmHg.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Estenose da Valva Aórtica/cirurgia , Próteses Valvulares Cardíacas , Hipertensão Pulmonar/etiologia , Idoso , Idoso de 80 Anos ou mais , Valva Aórtica/fisiopatologia , Valva Aórtica/cirurgia , Estenose da Valva Aórtica/complicações , Estenose da Valva Aórtica/fisiopatologia , Cateterismo Cardíaco , Feminino , Hemodinâmica , Humanos , Hipertensão Pulmonar/fisiopatologia , Masculino , Pessoa de Meia-Idade , Prognóstico
6.
Clin Nephrol ; 42(5): 309-14, 1994 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-7851032

RESUMO

The objectives of this study were to evaluate the specific effect of the ACE-inhibitor lisinopril on myocardial mass and diastolic function in uremic patients using a protocol designed to leave blood pressure unchanged. Nineteen hemodialysis patients (7 males; mean age: 55 +/- 13 years; mean time on dialysis: 44 +/- 35 months) received lisinopril for 6 months in addition to their preexistent antihypertensive treatment regimens (mean: 1.4 +/- 0.8 drugs). Doses of antihypertensive drugs were adjusted to keep both systolic and diastolic blood pressure stable. Nine patients were withdrawn from lisinopril treatment after 43 +/- 33 days because of hypotension (n = 4), withdrawn consent (n = 3), stroke (n = 1) and cough (n = 1). Seven of them were further studied as controls. Ten patients received 6.4 +/- 4 mg lisinopril as a mean for 6 months. Mean myocardial mass, calculated by M-mode echocardiography, was 324 +/- 103 g before, and 313 +/- 79 g after 6 months of lisinopril treatment. In the control patients, myocardial mass was 318 +/- 110 g initially, and after 6 months, it was 334 +/- 159 g. Early and late transmitral diastolic flow velocities were not significantly influenced by lisinopril. Throughout the study, both the systolic and diastolic 24-h mean blood pressure levels remained stable (systolic: before: 145 +/- 19 mmHg, at 6 months: 147 +/- 17 mmHg; diastolic: before: 87 +/- 12 mmHg, at 6 months 87 +/- 10 mmHg). Thus, no specific effect of lisinopril on regression of myocardial hypertrophy or improvement of diastolic function could be observed within a 6-month period in this small group of hemodialysis patients.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Anti-Hipertensivos/uso terapêutico , Diástole/efeitos dos fármacos , Hipertensão/tratamento farmacológico , Hipertrofia Ventricular Esquerda/tratamento farmacológico , Lisinopril/uso terapêutico , Diálise Renal , Função Ventricular Esquerda/efeitos dos fármacos , Pressão Sanguínea/efeitos dos fármacos , Ecocardiografia , Ecocardiografia Doppler , Feminino , Humanos , Hipertensão/complicações , Hipertrofia Ventricular Esquerda/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Fatores de Tempo , Uremia/complicações , Uremia/terapia
7.
J Interv Card Electrophysiol ; 3(4): 311-9, 1999 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-10525245

RESUMO

The local dispersion of conduction and refractoriness has been considered essential for induction of atrial arrhythmias. This study sought to determine whether a difference of refractoriness and vulnerability for induction of atrial fibrillation between trabeculated and smooth as well as high and low right atrium may contribute to initiation of atrial fibrillation in dogs. In 14 healthy mongrel dogs weighing 22.4 +/- 1 kg, closed-chest endocardial programmed stimulation was performed from four distinct right atrial sites. Atrial refractory periods and vulnerability for induction of atrial fibrillation or premature atrial complexes were determined during a basic cycle length of 400 and 300 ms and an increasing pacing current strength. For a pacing cycle length of 300 ms, atrial refractory periods were longer on the smooth, as compared to the trabeculated right atrium (102 +/- 25 vs. 97 +/- 17 ms, p < 0.05), whereas for a pacing cycle length of 400 ms, there was no significant difference. The duration of the vulnerability zone for induction of atrial fibrillation was longer on the smooth right atrium, for a cycle length of both 400 ms (40 +/- 30 vs. 31 +/- 22 ms; p < 0.05) and 300 ms (33 +/- 25 vs. 23 +/- 21 ms; p < 0. 01). When comparing high and low right atrium, refractory periods were longer on the the low right atrium, for a cycle length of both 400 ms (111 +/- 23 vs. 94 +/- 24 ms; p < 0.01) and 300 ms (104 +/- 20 vs. 96 +/- 23 ms; p < 0.01). For a pacing cycle length of 300 ms, the duration of the atrial fibrillation vulnerability zone was longer for the high, as compared to the low right atrium (34 +/- 22 vs. 22 +/- 22, p < 0.01). Seven dogs with easily inducible episodes of atrial fibrillation demonstrated significantly shorter refractory periods as compared to 7 non-vulnerable dogs, regardless of pacing site and current strength. In conclusion, significant differences in refractoriness and vulnerability for induction of atrial fibrillation can be observed in the area of the crista terminalis in healthy dogs. Thus, local anatomic factors may play a role in the initiation of atrial fibrillation.


Assuntos
Fibrilação Atrial/etiologia , Função do Átrio Direito/fisiologia , Período Refratário Eletrofisiológico/fisiologia , Animais , Estimulação Cardíaca Artificial , Suscetibilidade a Doenças , Cães
8.
Med Biol Eng Comput ; 42(2): 146-50, 2004 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15125142

RESUMO

Non-invasive imaging of cardiac electrophysiology provides a non-invasive way of obtaining information about electrical excitation. An iterative algorithm based on a general regularisation scheme for non-linear, ill-posed problems in Hilbert scales was applied to the electrocardiographic inverse problem, imaging the ventricular surface activation time (AT) map. This method was applied to electrocardiographic data from a 31-year-old healthy volunteer and a 24-year-old patient suffering from a Wolff-Parkinson-White (WPW) syndrome. The objective was to evaluate non-invasive AT imaging of an autonomous sinus rhythm and to quantify the localisation error of non-invasive AT imaging by localising the accessory pathway of the WPW syndrome and a pacing site for left ventricle pacing. The distances between the invasive and non-invasive localisation of the pacing site and the accessory pathway were 8 mm and 5 mm. The clinical case presented, shows that this non-invasive AT imaging approach may enable the reconstruction of single focal events with sufficient accuracy for potential clinical application.


Assuntos
Mapeamento Potencial de Superfície Corporal/métodos , Síndrome de Wolff-Parkinson-White/diagnóstico , Adulto , Algoritmos , Humanos , Imageamento por Ressonância Magnética , Masculino , Processamento de Sinais Assistido por Computador
9.
Wien Klin Wochenschr ; 108(10): 289-92, 1996.
Artigo em Alemão | MEDLINE | ID: mdl-8711914

RESUMO

The detection of all teeth with periapical pathological conditions and optimal treatment of the affected teeth are a part of the evaluation program for patients who are scheduled to undergo cardiac value replacement. 48 patients (50 value replacement operations) were evaluated for the incidence of periapical pathological conditions, as well as for the different kinds of oral surgical interventions. A periapical pathological condition was present in 28 of 48 patients (58.3%). In general, the incidence of a dental focus was significantly higher in patients awaiting aortic valve replacement than in patients undergoing mitral valve replacement (69.7% vs. 23.1%; p < 0.01). Patients for aortic valve replacement presented significantly more periapical pathological conditions than patients for mitral valve replacement (1.7 vs. 0.8). Optimal timing of dental consultations is helpful in the oral rehabilitation of patients about to undergo a valve replacement procedure. Furthermore, close interdisciplinary cooperation is necessary to minimize the social and psychological problems following unexpected tooth extractions. Cardiologists and heart surgeons have an important role in the organisation of the oral rehabilitation of patients undergoing valve replacement procedures.


Assuntos
Endocardite Bacteriana/prevenção & controle , Doenças das Valvas Cardíacas/cirurgia , Próteses Valvulares Cardíacas , Abscesso Periapical/terapia , Complicações Pós-Operatórias/prevenção & controle , Cuidados Pré-Operatórios , Doenças Dentárias/terapia , Adulto , Idoso , Valva Aórtica/cirurgia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valva Mitral/cirurgia , Abscesso Periapical/diagnóstico , Radiografia Panorâmica , Fatores de Risco , Doenças Dentárias/diagnóstico
10.
Wien Klin Wochenschr ; 110(8): 292-5, 1998 Apr 24.
Artigo em Alemão | MEDLINE | ID: mdl-9615961

RESUMO

In the present study pulmonary function test data were obtained from 15 healthy volunteers and 15 patients with slightly impaired ventilation during both normal and maximally reduced opening of the mouth (trismus, intercuspid position). The aim of the study was to examine the effects of complete trismus on pulmonary function using objective and subjective parameters. In maximally reduced mouth opening, both groups showed an impairment of all subjective and objective pulmonary function test data. In healthy volunteers, the significant changes in the test data (p < 0.05) simulated mild to moderate pulmonary impairment, whereas patients with an already impaired pulmonary function showed a marked deterioration of their initial respiratory condition. The results of the subjective and objective parameters examined indicate that an intercuspid position (trismus) further aggravates pulmonary functional impairments. Complete trismus can be considered a risk factor to pulmonary function in patients using mouth-breathing as primary or supportive mode of respiration.


Assuntos
Pneumopatias Obstrutivas/fisiopatologia , Medidas de Volume Pulmonar , Respiração Bucal/fisiopatologia , Trismo/fisiopatologia , Adulto , Resistência das Vias Respiratórias/fisiologia , Dispneia/fisiopatologia , Feminino , Humanos , Pneumopatias Obstrutivas/diagnóstico , Masculino , Ventilação Pulmonar/fisiologia , Valores de Referência , Trismo/diagnóstico
11.
Wien Klin Wochenschr ; 108(5): 133-6, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-8901126

RESUMO

Assessment of heart rate variability as a measure of sympathovagal balance has proven useful in the risk stratification of patients with coronary artery disease. Since diabetic subjects with autonomic neuropathy, carrying a high risk of cardiovascular events, have been shown to have reduced heart rate variability, we performed a short-term (600 RR-intervals) frequency and time domain analysis in type I diabetic subjects. 19 patients without clinical signs of autonomic neuropathy were compared with 11 age- and sex-matched control persons. At a comparable cycle length, diabetic subjects differed significantly from healthy controls in all calculated time domain parameters (standard deviation: 41 +/- 23 vs. 66 +/- 17 ms, p = 0.005; root mean square successive difference of normal RR-intervals: 25 +/- 17 vs. 41 +/- 17 ms, p = 0.02) and frequency domain parameters (low frequency: 58 +/- 67 vs. 158 +/- 97 ms2, p = 0.002; high frequency: 29 +/- 42 vs. 85 +/- 96 ms2, p = 0.03). Thus, short-term frequency and time domain analysis of heart rate variability can be used easily and quickly in an outpatient setting for estimation of changes in the sympathovagal balance in diabetic subjects. However, the prognostic significance and the influence of drugs on impaired heart rate variability in diabetic subjects have yet to be determined.


Assuntos
Doenças do Sistema Nervoso Autônomo/fisiopatologia , Doença das Coronárias/fisiopatologia , Diabetes Mellitus Tipo 1/fisiopatologia , Frequência Cardíaca/fisiologia , Adolescente , Adulto , Doenças do Sistema Nervoso Autônomo/diagnóstico , Doença das Coronárias/diagnóstico , Diabetes Mellitus Tipo 1/diagnóstico , Eletrocardiografia , Feminino , Análise de Fourier , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Processamento de Sinais Assistido por Computador , Sistema Nervoso Simpático/fisiopatologia , Nervo Vago/fisiopatologia
12.
Wien Klin Wochenschr ; 108(17): 552-4, 1996.
Artigo em Alemão | MEDLINE | ID: mdl-8992788

RESUMO

The development of left main coronary artery stenosis is a rare complication arising after aortic valve replacement. We report the different clinical course of two cases. One patient developed typical exertional angina 3 months after uneventful aortica valve replacement. Coronary stenosis had been excluded on preoperative coronary angiography. One day before hospital admission for coronary angiography the patient died suddenly. The second patient reported symptoms typical of angina 6 months after aortic valve replacement. Coronary angiography revealed critical left coronary ostial stenosis, which was successfully treated by surgical revascularization. These cases demonstrate the rare, yet potentially fatal complication of left coronary ostial stenosis. Early coronary angiography seems warranted in the event of typical exertional angina, even after angiographic exclusion of relevant coronary artery stenosis before aortic valve replacement.


Assuntos
Estenose da Valva Aórtica/cirurgia , Angiografia Coronária , Doença das Coronárias/diagnóstico por imagem , Próteses Valvulares Cardíacas , Complicações Pós-Operatórias/diagnóstico por imagem , Cardiopatia Reumática/cirurgia , Estenose da Valva Aórtica/diagnóstico por imagem , Ponte de Artéria Coronária , Doença das Coronárias/cirurgia , Morte Súbita Cardíaca/etiologia , Feminino , Humanos , Pessoa de Meia-Idade , Complicações Pós-Operatórias/cirurgia , Reoperação , Cardiopatia Reumática/diagnóstico por imagem
13.
Wien Klin Wochenschr ; 108(12): 358-62, 1996.
Artigo em Alemão | MEDLINE | ID: mdl-8767408

RESUMO

Since 24-hour blood pressure monitoring seems to be superior to occasional blood pressure measurement as far as risk stratification is concerned, we compared the two methods in patients with secondary hypertension and left ventricular hypertrophy. In 26 haemodialysis patients (12 male, mean age 54 +/- 13 years), the mean occasional blood pressure values during haemodialysis were 147 +/- 18/82 +/- 9 mmHg, the mean 24-hour blood pressure values were 145 +/- 21/ 85 +/- 13 mmHg, during the day 145 +/- 23/86 +/- 13, during the night 143 +/- 25/81 +/- 13 mmHg. The nocturnal reduction of mean blood pressure was -3.6 +/- 7%. Both methods of blood pressure monitoring showed a significant correlation with the relevant echocardiographic parameters of left ventricular hypertrophy, cardiac mass and interventricular septum diameter. Patients with and without a nocturnal reduction in blood pressure could not be differentiated by the mean occasional blood pressure values. Therefore, 24 h ambulatory blood pressure monitoring seems warranted in this high risk group, especially to monitor antihypertensive drug therapy.


Assuntos
Monitores de Pressão Arterial , Hipertrofia Ventricular Esquerda/fisiopatologia , Monitorização Fisiológica , Diálise Renal , Adulto , Idoso , Pressão Sanguínea/fisiologia , Ritmo Circadiano/fisiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Fatores de Risco
14.
Wien Klin Wochenschr ; 124(9-10): 340-7, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22576960

RESUMO

In any type of invasive surgery, the patient's individual risk of thromboembolism has to be weighed against the risk of bleeding. Based on various everyday situations in clinical routine, the purpose of the present expert recommendations is to provide appropriate perioperative and periinterventional management for patients with atrial fibrillation undergoing long-term treatment with the thrombin inhibitor dabigatran. As we currently have no routine laboratory test to measure therapeutic levels of the substance or the risk of bleeding, general measures such as a standardized documentation of the patient's history, a sufficient time interval between the last preoperative dose and the procedure, and careful control of local hemostasis should be given special attention.


Assuntos
Fibrilação Atrial/tratamento farmacológico , Fibrilação Atrial/cirurgia , Benzimidazóis/efeitos adversos , Benzimidazóis/uso terapêutico , Hemorragia Pós-Operatória/induzido quimicamente , Hemorragia Pós-Operatória/prevenção & controle , Pré-Medicação/normas , beta-Alanina/análogos & derivados , Áustria , Dabigatrana , Feminino , Humanos , Masculino , Assistência Perioperatória/métodos , Assistência Perioperatória/normas , Guias de Prática Clínica como Assunto , Pré-Medicação/métodos , beta-Alanina/efeitos adversos , beta-Alanina/uso terapêutico
16.
Pacing Clin Electrophysiol ; 22(4 Pt 1): 643-54, 1999 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10234718

RESUMO

Animal models and human studies of atrial activation mapping and entrainment have considerably enhanced our understanding of the anatomical substrate for atrial flutter and created the basis for a definite cure with radiofrequency catheter ablation. As atrial flutter has now become a curable arrhythmia, emphasis is shifting to understand the most common arrhythmia: atrial fibrillation. Furthermore, from clinical observation, it is apparent that there is a relationship between atrial fibrillation and atrial flutter in patients with atrial arrhythmias. Techniques that have informed our understanding of the anatomical basis of atrial flutter may also be useful in understanding the relationship between atrial fibrillation and flutter, including animal models, clinical endocardial mapping, and intracardiac anatomical imaging. Thus, atrial anatomy and its relationship to electrophysiological findings, and the role of partial or complete conduction barriers around which reentry can and cannot occur, may be of importance for atrial fibrillation as well. Ultimately, the relationship between atrial fibrillation and atrial flutter may inform our understanding of the mechanisms of atrial fibrillation itself, and help to develop new approaches to device, catheter-based, and pharmacological therapy for atrial fibrillation.


Assuntos
Fibrilação Atrial/fisiopatologia , Flutter Atrial/fisiopatologia , Animais , Fibrilação Atrial/patologia , Fibrilação Atrial/terapia , Flutter Atrial/patologia , Flutter Atrial/cirurgia , Mapeamento Potencial de Superfície Corporal , Ablação por Cateter , Modelos Animais de Doenças , Eletrocardiografia , Átrios do Coração/inervação , Átrios do Coração/patologia , Átrios do Coração/fisiopatologia , Sistema de Condução Cardíaco/fisiopatologia , Humanos
17.
Dtsch Med Wochenschr ; 121(46): 1424-7, 1996 Nov 15.
Artigo em Alemão | MEDLINE | ID: mdl-8974874

RESUMO

HISTORY AND CLINICAL FINDINGS: Case 1: a 20-year-old previously healthy man sustained multiple nonvascular injuries without visible chest trauma in a car accident. Four days later a loud systolic murmur was heard over the heart. Case 2: a 21-year-old man similarly sustained in a car accident multiple injuries without visible chest involvement but causing haemorrhagic shock. A loud systolic heart murmur was heard and after shock treatment he developed left heart failure requiring catecholamine infusions. INVESTIGATIONS: Echocardiography demonstrated posttraumatic ventricular septal rupture in both patients. Cardiac catheterisation revealed a small left to right (1 : 1.6) shunt in case 1, and a large one, 1 : 3, with markedly elevated pulmonary artery pressure in case 2. COURSE: In case 1, no treatment was needed as the intracardiac shunt was small and there were no symptoms. But in case 2 the large shunt with pulmonary hypertension required operative closure with a Dacron patch 2 days after the diagnosis had been established. CONCLUSION: Ventricular septal rupture after blunt trauma to the chest is a rare occurrence. Even though in general the prognosis is good, a large intracardiac shunt may require early surgical repair.


Assuntos
Ruptura Cardíaca/etiologia , Septos Cardíacos/lesões , Traumatismo Múltiplo/complicações , Traumatismos Torácicos/complicações , Ferimentos não Penetrantes/complicações , Acidentes de Trânsito , Adulto , Cateterismo Cardíaco , Ecocardiografia Doppler em Cores , Eletrocardiografia , Emergências , Ruptura Cardíaca/diagnóstico , Ruptura Cardíaca/cirurgia , Septos Cardíacos/diagnóstico por imagem , Septos Cardíacos/cirurgia , Humanos , Masculino , Traumatismo Múltiplo/diagnóstico , Traumatismos Torácicos/diagnóstico , Ferimentos não Penetrantes/diagnóstico
18.
Circulation ; 96(10): 3484-91, 1997 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-9396445

RESUMO

BACKGROUND: A transitional rhythm precedes the spontaneous onset of atrial flutter in an animal model, but few data are available in man. METHODS AND RESULTS: In 10 patients, 16 episodes of atrial fibrillation (166+/-236 seconds) converting into atrial flutter during electrophysiological evaluation were analyzed. A 20-pole catheter was used for mapping the right atrial free wall. Preceding the conversion was a characteristic sequence of events: (1) a gradual increase in atrial fibrillation cycle length (150+/-25 ms after onset, 166+/-28 ms before conversion, P<.01); (2) an electrically silent period (267+/-45 ms); (3) "organized atrial fibrillation" (cycle length, 184+/-24 ms) with the same right atrial free wall activation direction as during atrial flutter; (4) another delay on the lateral right atrium (283+/-52 ms); and (5) typical atrial flutter (cycle length, 245+/-38 ms). The coronary sinus generally had a different rate than the right atrial free wall until the beat that initiated flutter, when right atrium and coronary sinus were activated in sequence. During 1313 seconds of fibrillation, there were 171 episodes of "organized atrial fibrillation." An additional activation delay at least 30 ms longer than the mean organized atrial fibrillation cycle length was sensitive (100%) and specific (99%) for impending organization into atrial flutter. During organized atrial fibrillation, right atrial free wall activation was craniocaudal in 70% and caudocranial in 30%, which may explain why counterclockwise flutter is a more common clinical rhythm than clockwise flutter. Atrial flutter never degenerated into fibrillation, even after adenosine infusion. CONCLUSIONS: Anatomic barriers, along with statistical properties of conduction and refractoriness during atrial fibrillation, may explain the remarkably stereotypical pattern of endocardial activation during the initiation of atrial flutter via fibrillation and the rarity of degeneration of flutter to fibrillation once it stabilizes.


Assuntos
Fibrilação Atrial/complicações , Fibrilação Atrial/fisiopatologia , Flutter Atrial/etiologia , Flutter Atrial/fisiopatologia , Idoso , Idoso de 80 Anos ou mais , Eletrocardiografia , Feminino , Previsões , Humanos , Masculino , Pessoa de Meia-Idade
19.
Pacing Clin Electrophysiol ; 24(3): 316-22, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11310300

RESUMO

The effect of dual site pacing for prevention of atrial fibrillation may be due to synchronization of right and left atrial activation. Little is known, however, about the effect of pacing from single right atrial sites on differences in interatrial conduction. Twenty-eight patients without structural heart disease were studied following radiofrequency catheter ablation of supraventricular arrhythmias. Pacing was performed using standard multipolar catheters from the presumed insertion site of Bachmann's bundle, the coronary sinus ostium, the high lateral right atrium, and the right atrial appendage (n = 8 patients). Bipolar recording was performed from the distal coronary sinus, the high and low lateral right atrium, and the posterolateral left atrium (n = 13 patients). The longest conduction time from each pacing to each recording site was considered the total atrial activation time for the respective pacing site. During high right atrial pacing, the total atrial activation time was determined by the conduction to the distal coronary sinus (118 +/- 18 ms), during coronary sinus ostium pacing by the conduction to the high right atrium (94 +/- 18 ms), and during Bachmann's bundle pacing by the conduction to the distal coronary sinus (74 +/- 18 ms). The total atrial activation time was significantly shorter during pacing from Bachmann's bundle, as compared to pacing from other right atrial sites. Thus, in normal atria, pacing from the insertion of Bachmann's bundle causes a shorter total atrial activation time and less interatrial conduction delay, as compared to pacing from other right atrial sites. These findings may have implications for alternative pacing sites for prevention of atrial fibrillation.


Assuntos
Fibrilação Atrial/prevenção & controle , Estimulação Cardíaca Artificial/métodos , Marca-Passo Artificial , Análise de Variância , Fibrilação Atrial/fisiopatologia , Ablação por Cateter , Feminino , Sistema de Condução Cardíaco/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Processamento de Sinais Assistido por Computador , Taquicardia Supraventricular/cirurgia , Resultado do Tratamento
20.
Eur Heart J ; 14(11): 1579-81, 1993 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-8299645

RESUMO

As a result of chronic ergotamine abuse, reversible arterial narrowing has been documented angiographically in peripheral, but not in coronary arteries. We report on a patient with no cardiovascular risk factors, but because of chronic ergotamine abuse suffered on acute myocardial infarction, complicated by ventricular fibrillation. Coronary angiography performed 3 days after resuscitation revealed a distal occlusion of the left anterior descending artery. Three months later, spontaneous recanalization had occurred, and no residual narrowing was seen angiographically. Thus, surveillance of patients with migraine headache to avoid chronic ergotamine abuse is recommended to prevent cardiovascular complications.


Assuntos
Ergotamina/efeitos adversos , Infarto do Miocárdio/induzido quimicamente , Transtornos Relacionados ao Uso de Substâncias/complicações , Doença das Coronárias/induzido quimicamente , Feminino , Humanos , Pessoa de Meia-Idade , Transtornos de Enxaqueca/tratamento farmacológico
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