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1.
Int J Cardiol ; 405: 131865, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38365013

RESUMO

BACKGROUND: Finding patients with chronic coronary syndromes (CCS) whom revascularization could benefit, is complicated. Myocardial flow reserve (MFR), a measurement of myocardial perfusion, has proven prognostic value on survival and risk of major adverse cardiac events (MACE). We investigated if MFR identifies who may benefit from revascularization. METHODS: Among 7462 patients from Danish hospitals examined with 82Rb PET between January 2018 and August 2020, patients with ≥5% reversible perfusion defects were followed for MACE and all-cause mortality. Associations between revascularisation (within 90 days) and outcomes according to MFR (< and ≥ 2) was assessed by Cox regression adjusted by inverse probability weighting for demographics, cardiovascular risk factors, comorbidities, and 82Rb PET variables. RESULTS: Of 1806 patients with ≥5% reversible perfusion defect, 893 (49%) had MFR < 2 and 491 underwent revascularisation (36.6% in MFR < 2 versus 17.9% MFR ≥ 2, p < 0.001). During a median follow-up of 37.0 [31.0-45.8 IQR] months, 251 experienced a MACE and 173 died. Revascularisation was associated with lower adjusted risk of all-cause mortality (hazard ratio [HR], 0.51 [95% CI, 0.30-0.88], p = 0.015) and MACE (HR, 0.54 [0.33-0.87], p = 0.012) in patients with MFR < 2 but not MFR ≥ 2 for all-cause mortality (HR 1.33 [0.52-3.40], p = 0.542) and MACE (HR 1.50 [0.79-2.84], p = 0.211). MFR significantly modified the association between revascularisation and MACE, but not all-cause mortality (interaction p-value 0.021 and 0.094, respectively). CONCLUSIONS: Revascularization was associated with improved prognosis among patients with impaired MFR. No association was seen in patients with normal MFR. In patients with regional ischemia, MFR may identify patients with a prognostic benefit from revascularization.


Assuntos
Reserva Fracionada de Fluxo Miocárdico , Revascularização Miocárdica , Tomografia por Emissão de Pósitrons , Sistema de Registros , Radioisótopos de Rubídio , Humanos , Masculino , Feminino , Idoso , Revascularização Miocárdica/métodos , Revascularização Miocárdica/estatística & dados numéricos , Pessoa de Meia-Idade , Tomografia por Emissão de Pósitrons/métodos , Reserva Fracionada de Fluxo Miocárdico/fisiologia , Dinamarca/epidemiologia , Seguimentos , Resultado do Tratamento , Doença da Artéria Coronariana/cirurgia , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/fisiopatologia , Doença da Artéria Coronariana/mortalidade
2.
Catheter Cardiovasc Interv ; 74(5): 710-7, 2009 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-19496145

RESUMO

BACKGROUND: Spontaneous coronary artery dissection (SCAD) is a rare cause of acute coronary syndrome (ACS) that associates with a high acute-phase mortality rate, whereas long-term outcome is less well described. OBJECTIVE: To describe the incidence, predictors, and prognosis of SCAD. DESIGN: Retrospective case-identification study from the Western Denmark Heart Registry and the database of the Forensic Institute at Aarhus University from 1999 through 2007. RESULTS: SCAD was documented in 22 of 32,869 (0.7 per thousand) angiograms in the angiographic registry. The SCAD incidence among cases of ACS was 22 of 11,175 (2.0 per thousand). None was seen in the forensic database. The mean age was 48.7 +/- 8.9 years (range: 37-71 years). Females constituted 17 of 22 (77%) patients and all had undergone one or more pregnancies; two cases occurred in the postpartum period. The left descending artery (LAD) was the predominant site of entry. The age distribution, prevalence of the cardiovascular risk factors, presence of coronary atherosclerosis, and entry of the dissection were comparable among genders. Treatment was percutaneous coronary intervention in 13 of 22 (59%), coronary artery bypass operation in 2 of 22 (9%), and medical treatment in 7 of 22 (32%) patients. The mean follow-up period was 3.6 +/- 2.9 years. One patient suffered from recurrent SCAD; another patient died suddenly. The MACE- (cardiac death, nonfatal myocardial infarction, and new revascularization) free survival was 81% after 24 months. CONCLUSION: SCAD is a rare disease that mainly affects younger women. Compared with earlier reports, the prognosis seems to be improved by early diagnosis and interventional treatment.


Assuntos
Síndrome Coronariana Aguda/epidemiologia , Dissecção Aórtica/epidemiologia , Aneurisma Coronário/epidemiologia , Síndrome Coronariana Aguda/etiologia , Síndrome Coronariana Aguda/mortalidade , Síndrome Coronariana Aguda/terapia , Adulto , Fatores Etários , Idoso , Dissecção Aórtica/complicações , Dissecção Aórtica/diagnóstico , Dissecção Aórtica/mortalidade , Dissecção Aórtica/terapia , Angioplastia Coronária com Balão , Fármacos Cardiovasculares/uso terapêutico , Aneurisma Coronário/complicações , Aneurisma Coronário/diagnóstico , Aneurisma Coronário/mortalidade , Aneurisma Coronário/terapia , Angiografia Coronária , Ponte de Artéria Coronária , Dinamarca/epidemiologia , Intervalo Livre de Doença , Feminino , Humanos , Incidência , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Recidiva , Sistema de Registros , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Fatores Sexuais , Fatores de Tempo , Resultado do Tratamento , Ultrassonografia de Intervenção
3.
Int J Cardiovasc Imaging ; 35(9): 1709-1720, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31016502

RESUMO

We aimed to identify factors influencing the sensitivity of perfusion imaging after an initial positive coronary computed tomography angiography (CCTA) using invasive coronary angiography (ICA) with conditional fractional flow reserve (FFR) as reference. Secondly we aimed to identify factors associated with revascularisation and to evaluate treatment outcome after ICA. We analysed 292 consecutive patients with suspected significant coronary artery disease (CAD) at CCTA, who underwent perfusion imaging with either cardiac magnetic resonance (CMR) or myocardial perfusion scintigraphy (MPS) followed by ICA with conditional FFR. Stratified analysis and uni- and multiple logistic regression analyses were performed to identify predictors of diagnostic agreement between perfusion scans and ICA and predictors of revascularisation. Myocardial ischemia evaluated with perfusion scans was present in 65/292 (22%) while 117/292 (40%) had obstructive CAD evaluated by ICA. Revascularisation rate was 90/292 (31%). The overall sensitivity for perfusion scans was 39% (30-48), specificity 89% (83-93), PPV 69% (57-80) and NPV 68% (62-74). Stratified analysis showed higher sensitivities in patients with multi-vessel disease at CCTA 49% (37-60) and typical chest pain 50% (37-60). Predictors of revascularisation were multi-vessel disease by CCTA (OR 3.51 [1.91-6.48]) and a positive perfusion scan (OR 4.69 [2.49-8.83]). The sensitivity for perfusion scans after CCTA was highest in patients with typical angina and multiple lesions at CCTA and predicted diagnostic agreement between perfusion scans and ICA. Abnormal perfusion and multi vessel disease at CCTA predicted revascularisation.


Assuntos
Angiografia por Tomografia Computadorizada , Angiografia Coronária/métodos , Doença da Artéria Coronariana/diagnóstico por imagem , Vasos Coronários/diagnóstico por imagem , Reserva Fracionada de Fluxo Miocárdico , Imageamento por Ressonância Magnética , Imagem de Perfusão do Miocárdio/métodos , Cintilografia/métodos , Idoso , Doença da Artéria Coronariana/fisiopatologia , Doença da Artéria Coronariana/cirurgia , Vasos Coronários/fisiopatologia , Vasos Coronários/cirurgia , Dinamarca , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Revascularização Miocárdica , Valor Preditivo dos Testes , Reprodutibilidade dos Testes , Índice de Gravidade de Doença , Resultado do Tratamento
4.
Eur Heart J Cardiovasc Imaging ; 19(4): 369-377, 2018 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-29447342

RESUMO

Aims: Perfusion scans after coronary computed tomography angiography (CCTA) in patients with suspected coronary artery disease (CAD) may reduce unnecessary invasive coronary angiographies (ICAs). However, the diagnostic accuracy of perfusion scans after primary CCTA is unknown. The aim of this study was to determine the diagnostic accuracy of cardiac magnetic resonance (CMR) and myocardial perfusion scintigraphy (MPS) against ICA with fractional flow reserve (FFR) in patients suspected of CAD by CCTA. Methods and results: Included were consecutive patients (1675) referred to CCTA with symptoms of CAD and low/intermediate risk profile. Patients with suspected CAD based on CCTA were randomized 1:1 to CMR or MPS followed by ICA with FFR. Obstructive CAD was defined as FFR ≤ 0.80 or > 90% diameter stenosis by visual assessment. After initial CCTA, 392 patients (23%) were randomized; 197 to CMR and 195 to MPS. Perfusion scans and ICA were completed in 292 patients (CMR 148, MPS 144). Based on the ICA, 117/292 (40%) patients were classified with CAD. Sensitivity, specificity, negative predictive value (NPV), and positive predictive value (PPV) for CMR were 41%, 95% CI [28-54], 84% [75-91], 62% [45-78], and 68% [58-76], respectively. For the MPS group 36% [24-50], 94% [87-98], 81% [61-93], and 68% [59-76], respectively. Conclusion: Patients with low/intermediate CAD risk and a positive CCTA scan represent a challenge to perfusion techniques indicated by the low sensitivity of both CMR and MPS with FFR as a reference. The mechanisms underlying this discrepancy need further investigation.


Assuntos
Angiografia por Tomografia Computadorizada/métodos , Angiografia Coronária/métodos , Doença da Artéria Coronariana/diagnóstico por imagem , Imagem Cinética por Ressonância Magnética/métodos , Imagem de Perfusão do Miocárdio/métodos , Idoso , Doença da Artéria Coronariana/fisiopatologia , Feminino , Reserva Fracionada de Fluxo Miocárdico/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Sensibilidade e Especificidade
5.
Int J Cardiol ; 71(3): 235-42, 1999 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-10636529

RESUMO

AIM: To compare the QT dispersion in unselected patients with insulin-dependent diabetes mellitus to non-diabetic control subjects and to assess the association between the QT dispersion and cardiac autonomic neuropathy, ischaemic heart disease, blood pressure level and nephropathy. METHODS: 42 patients with insulin-dependent diabetes mellitus and 80 control subjects aged 40-57 years participated. The QT interval was measured in a resting 12-lead electrocardiogram (ECG) and the QT dispersion defined as the difference between the maximum and minimum QT interval. Bazett's formula was used to correct for heart rate (QTc). The degree of cardiac autonomic neuropathy was assessed by five function tests and ischaemic heart disease was defined by a previous myocardial infarction, ECG abnormalities or a positive exercise test. RESULTS: Compared to control subjects, diabetic patients had a longer QTc interval (433 vs. 416 ms; P=0.002) and a higher QT dispersion (36 vs. 30 ms; P=0.02). In the diabetic group, the QTc interval was prolonged in patients with autonomic neuropathy (449 vs. 420 ms; P=0.007) and the QT dispersion was increased in patients with ischaemic heart disease (51 vs. 33 ms; P=0.004). No association was found to urinary albumin excretion rate or blood pressure. CONCLUSION: The QT dispersion as well as the QTc interval is increased in patients with insulin-dependent diabetes mellitus. The association between QT dispersion and ischaemic heart disease indicates that abnormalities in cardiac repolarisation may be caused by complications to diabetes rather than diabetes in itself.


Assuntos
Diabetes Mellitus Tipo 1/fisiopatologia , Eletrocardiografia , Isquemia Miocárdica/fisiopatologia , Adulto , Idoso , Sistema Nervoso Autônomo/fisiopatologia , Neuropatias Diabéticas/complicações , Neuropatias Diabéticas/fisiopatologia , Teste de Esforço , Feminino , Frequência Cardíaca , Humanos , Masculino , Pessoa de Meia-Idade , Isquemia Miocárdica/etiologia , Prognóstico
6.
Int J Cardiol ; 50(2): 153-62, 1995 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-7591326

RESUMO

To evaluate the impact of ectopic atrial activity and cardiac autonomic function for development of atrial fibrillation or flutter we studied 128 consecutive patients undergoing elective coronary artery bypass grafting. The patients were Holter monitored during a 96-h postoperative period. Autonomic balance was estimated by heart rate variability measurement. Thirty-eight (30%) patients developed sustained atrial fibrillation or flutter. Holter recordings were analyzed in a case-base design matching for age, beta-blocker treatment, and time elapsed after the operation. The number of supraventricular ectopic beats/h was increased (P < 0.01) in the case group during each of the last 7 h before onset of atrial fibrillation or flutter. Episodes of supraventricular tachycardia 62% vs. 26%; cases vs. controls (P = 0.007), episodes of non-sustained atrial fibrillation 29% vs. 0% (P = 0.0009), and episodes of non-sustained atrial flutter 15% vs. 0% (P = 0.05) were significant predictors of atrial fibrillation or flutter. Mean heart rate/h was increased in each of the 24 h preceding the arrhythmia. However, indexes of autonomic heart function did not differ significantly between groups. Patients developing atrial fibrillation or flutter after coronary artery bypass surgery present 'warning' atrial arrhythmias: numerous supraventricular ectopic beats, paroxysmal supraventricular tachycardia, and episodes of nonsustained atrial fibrillation and flutter.


Assuntos
Antagonistas Adrenérgicos beta/administração & dosagem , Fibrilação Atrial/fisiopatologia , Flutter Atrial/fisiopatologia , Ponte de Artéria Coronária , Doença das Coronárias/cirurgia , Metoprolol/administração & dosagem , Complicações Pós-Operatórias/fisiopatologia , Taquicardia Atrial Ectópica/fisiopatologia , Antagonistas Adrenérgicos beta/efeitos adversos , Adulto , Fatores Etários , Idoso , Fibrilação Atrial/diagnóstico , Flutter Atrial/diagnóstico , Sistema Nervoso Autônomo/efeitos dos fármacos , Sistema Nervoso Autônomo/fisiopatologia , Estudos de Casos e Controles , Eletrocardiografia Ambulatorial/efeitos dos fármacos , Feminino , Seguimentos , Átrios do Coração/efeitos dos fármacos , Átrios do Coração/fisiopatologia , Frequência Cardíaca/efeitos dos fármacos , Frequência Cardíaca/fisiologia , Humanos , Masculino , Metoprolol/efeitos adversos , Pessoa de Meia-Idade , Complicações Pós-Operatórias/diagnóstico , Fatores de Risco , Taquicardia Atrial Ectópica/diagnóstico , Taquicardia Paroxística/diagnóstico , Taquicardia Paroxística/fisiopatologia
7.
Int J Cardiol ; 36(3): 253-61, 1992 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-1358829

RESUMO

Atrial fibrillation and atrial flutter are common arrhythmias after coronary artery bypass grafting. Although the consequences of the arrhythmia are generally not life-threatening, it constitutes a major clinical problem often requiring conversion to sinus rhythm. Atrial fibrillation or flutter can result in hypotension, heart failure, pneumonia, and stroke. This article reviews the literature on epidemiology, electrophysiology, risk factors, and preventive trials. The major conclusions are: (1) In patients undergoing coronary artery bypass surgery, the incidence of postoperative atrial fibrillation or flutter is 20-30%, the peak incidence being on the second or third postoperative day. (2) The strongest independent preoperative predictor for atrial fibrillation or flutter is the patients' age. (3) Intra-atrial conduction delay recorded pre and peroperatively may predict development of atrial fibrillation. (4) Peroperative inducibility of atrial fibrillation by pacing the right atrium may identify patients at risk for postoperative atrial fibrillation. (5) Development of postoperative atrial fibrillation or flutter has not been associated with peroperative or postoperative events. (6) The specificity and sensitivity of age and other possible relevant factors for prediction of atrial fibrillation or flutter after coronary artery bypass grafting is low. (7) No effective prophylactic regimen has yet been established.


Assuntos
Fibrilação Atrial/epidemiologia , Flutter Atrial/epidemiologia , Ponte de Artéria Coronária/efeitos adversos , Complicações Pós-Operatórias/epidemiologia , Antagonistas Adrenérgicos beta/uso terapêutico , Fatores Etários , Fibrilação Atrial/tratamento farmacológico , Fibrilação Atrial/prevenção & controle , Flutter Atrial/tratamento farmacológico , Flutter Atrial/prevenção & controle , Estimulação Cardíaca Artificial , Eletrofisiologia , Estudos de Avaliação como Assunto , Humanos , Incidência , Complicações Pós-Operatórias/tratamento farmacológico , Complicações Pós-Operatórias/prevenção & controle , Valor Preditivo dos Testes , Fatores de Risco , Sensibilidade e Especificidade , Fatores de Tempo
8.
Int J Cardiol ; 58(2): 135-40, 1997 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-9049678

RESUMO

Ninety-eight patients, who developed atrial fibrillation/flutter after coronary artery bypass grafting within 1-6 days after surgery, were included into a double-blind, placebo-controlled, randomized trial to assess the efficacy and safety of dofetilide. Patients were randomly allocated to dofetilide 4 micrograms/kg i.v. (n = 33), dofetilide 8 micrograms/kg i.v. (n = 32) or placebo (n = 33) given intravenously over 15 min at a constant infusion rate. Responders were defined as patients who converted to sinus rhythm at any time during the initial 3 h after the start of the infusion. The conversion rates were 24% (8/33) on placebo, 36% (12/33) on dofetilide 4 micrograms/kg, and 44% (14/32) on dofetilide 8 micrograms/kg. The P-values (two-tailed) were 0.27 for dofetilide 4 micrograms/kg vs. placebo, 0.11 for dofetilide 8 micrograms/kg vs. placebo, and 0.10 for dose-response relationship. Short episodes of aberrant ventricular conduction and ventricular tachycardia were seen separately in three subjects after dofetilide 8 micrograms/kg. No episodes of torsades de pointes were noted. No negative inotropic effect was noted. In conclusion, dofetilide was well tolerated, but the effects on atrial fibrillation/flutter did not attain statistical significance, possibly due to the high placebo conversion rate.


Assuntos
Antiarrítmicos/uso terapêutico , Fibrilação Atrial/tratamento farmacológico , Flutter Atrial/tratamento farmacológico , Ponte de Artéria Coronária , Fenetilaminas/uso terapêutico , Complicações Pós-Operatórias/tratamento farmacológico , Sulfonamidas/uso terapêutico , Idoso , Fibrilação Atrial/etiologia , Flutter Atrial/etiologia , Intervalos de Confiança , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Efeito Placebo , Tamanho da Amostra , Resultado do Tratamento
9.
Med Biol Eng Comput ; 36(4): 438-44, 1998 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10198526

RESUMO

There is a growing interest in the analysis of beat-to-beat variations of the morphology (BBM) of cardiac waves in electrocardiograms (ECG). Such analyses are confronted with the low BBM-to-noise ratio. An ECG clustering technique is introduced that brings the benefits of signal averaging to BBM analysis and recovers the beat-to-beat pattern of BBM. ECG clustering aligns waves and sorts them into clusters. The precision of the alignment was enhanced by sub-sample alignment. Kohonen's self-organising neural networks identified the clusters of the cardiac waves during training. The subsequent clustering of a wave results in a label for the closest cluster, a distance to the cluster and optimal alignment. Furthermore, ECG clustering avoids base-line variations and amplitude modulation sufficiently to be applied to the QRS wave in the raw ECG. The technique is demonstrated on 14 subjects with coronary heart disease and no myocardial infarction, myocardial infarction, or inducible ventricular tachycardia. ECG clustering is a general-purpose technique for beat-to-beat analysis, where the variations are cyclic as in the sinus rhythm. Results show that beat-to-beat variations in the QRS morphology are in general cyclic, with a main period of about four cardiac cycles. All calculations were performed with the Cardio software.


Assuntos
Doença das Coronárias/diagnóstico , Eletrocardiografia/métodos , Processamento de Sinais Assistido por Computador , Humanos , Redes Neurais de Computação
10.
Child Abuse Negl ; 23(1): 15-29, 1999 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10075190

RESUMO

OBJECTIVE: According to sociological and ecological models of abuse, typically nonabusive parents could behave abusively towards their children under certain circumstances. The purpose of this study was to examine factors that place parents at risk of abusing their children by predicting parents' use of discipline practices and attitudes that may bias parents towards abusive behaviors, which we refer to as abuse-proneness. METHOD: A telephone interview was administered by the Gallup Organization to a nationally representative sample of 1,000 parents. Using a set of theoretically relevant risk factors, multiple regression was used to predict variations in parental attitudes (i.e., attitudes towards physical discipline and attitudes that devalue children) and parental discipline practices (i.e., physical discipline, nonphysical discipline, and verbal abuse). RESULTS: The findings confirmed the importance of examining elements of parental attitudes, history, personality characteristics, as well as religion and ideology in predicting abuse proneness. Child age also was an important predictor in all analyses except predicting parental attitudes that devalue children. The findings suggest also, however, that it may be unduly simplified to regard parents as somewhere on a continuum of nonpunitive to punitive disciplinarians. Social isolation was not a significant predictor in any of the analyses. CONCLUSIONS: Although many important theoretical predictors of abuse proneness were confirmed, many questions arise regarding the diversity of discipline practices that parents use, and the relevance of child's age and social isolation in predicting abuse proneness. Implications for practitioners and future research are discussed.


Assuntos
Atitude , Maus-Tratos Infantis , Pais , Adolescente , Adulto , Idoso , Análise Fatorial , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Análise de Regressão , Fatores de Risco , Fatores Socioeconômicos
11.
J Okla State Med Assoc ; 92(4): 193-8, 1999 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10213972

RESUMO

BACKGROUND AND PURPOSE: The explosion at the Murrah Federal Building in Oklahoma City on April 19, 1995, affected many members of the community as well as direct victims. Our goal was to measure the exposure and effects among the general population. METHODS: We conducted surveys of the Oklahoma City metropolitan area and a control area to measure exposure and impact, primarily stress and psychological distress. RESULTS: Of the adults in the Oklahoma City MSA, 61.5 percent (58.5 percent to 64.5 percent with 95 percent confidence) reported experiencing at least one direct result of the bombing. In population terms, about 433 thousand adults (between 412 thousand and 457 thousand, with 95 percent confidence) were exposed to one or more of the consequences of the bombing. Oklahomans reported higher rates (about double) of increased alcohol use, smoking more or starting smoking. They reported more stress (about double), psychological distress (about double), post-traumatic stress-disorder components, and intrusive thoughts (double) related to the bombing than in the control area. Oklahomans also reported higher rates of seeking help for their stress or taking steps to reduce stress. The differences persisted into 1996, more than a year after the bombing. CONCLUSION: The exposure to the bombing was widespread, including more than half the adults in the metropolitan area surrounding Oklahoma City. The psychological effects were high and, while decreasing, persisted more than a year after the bombing. Primary care practitioners should screen their patients, who may normally not be considered victims, for exposure to the effects of a terrorist disaster for an extended period of time.


Assuntos
Explosões , Saúde Mental , Estresse Psicológico , Adulto , Feminino , Humanos , Masculino , Oklahoma , Transtornos de Estresse Pós-Traumáticos/etiologia , Violência
12.
Ugeskr Laeger ; 160(7): 1001-5, 1998 Feb 09.
Artigo em Dinamarquês | MEDLINE | ID: mdl-9477747

RESUMO

Chronic atrial fibrillation is by definition always preceded by paroxysmal atrial fibrillation. The electropathophysiological mechanisms underlying paroxysmal atrial fibrillation are reviewed: atrial electrophysiological inhomogeneity, atrial ectopic activity, and cardiac autonomic dysfunction. Safe and effective interventions that prevent the progression from paroxysmal into chronic atrial fibrillation have not yet been developed. Such developments should be given high priority, as the consequences of chronic atrial fibrillation--stroke and heart failure--are unacceptable.


Assuntos
Fibrilação Atrial , Fibrilação Atrial/diagnóstico , Fibrilação Atrial/fisiopatologia , Fibrilação Atrial/prevenção & controle , Doença Crônica , Humanos
13.
Ugeskr Laeger ; 155(11): 769-74, 1993 Mar 15.
Artigo em Dinamarquês | MEDLINE | ID: mdl-8460426

RESUMO

The activity of the cardiac autonomic nervous system can be estimated by measurement of beat to beat variations in heart rate-heart rate variability (HRV). In survivors after myocardial infarction, reduced 24-hour HRV, is an independent predictor of mortality/sudden cardiac death. The attenuated HRV is presumed to indicate reduced vagal function and concomitant high sympathetic activity. In experimental studies, this combination reduces the threshold for inducing malignant tachyarrhythmias, and is very probably a clinically important factor for the evolution of ventricular arrhythmias. Measurement of HRV in ordinary 24-hour ECG recordings can, together with other non-invasive measurements, stratify arrhythmic risk in survivors of myocardial infarction.


Assuntos
Arritmias Cardíacas/diagnóstico , Morte Súbita Cardíaca , Frequência Cardíaca , Infarto do Miocárdio/mortalidade , Arritmias Cardíacas/etiologia , Ritmo Circadiano , Frequência Cardíaca/efeitos dos fármacos , Humanos , Infarto do Miocárdio/diagnóstico , Infarto do Miocárdio/fisiopatologia , Prognóstico
14.
Ugeskr Laeger ; 158(27): 3919-23, 1996 Jul 01.
Artigo em Dinamarquês | MEDLINE | ID: mdl-8701506

RESUMO

To investigate the impact of pre-operative autonomic balance and atrial ectopic activity on the risk of atrial fibrillation or flutter after aorto-coronary artery bypass surgery 24-hour Holter monitoring was analyzed in 102 patients before coronary artery bypass grafting. Index for vagal tone was calculated as % successive RR-interval differences > 6%. Twenty-nine (28%) of the 102 patients developed atrial fibrillation or flutter. Independent predictors (90% confidence interval) of postoperative atrial fibrillation or flutter were identified by logistic regression analysis: the independent predictors were older age, relative risk 1.07/year (1.02-1.12), vagal index < 10%, relative risk 4.50 (1.40-14.5), > or= 10 ectopic supraventricular beats/24 hour, relative risk 3.03 (1.05-8.72), and one or more event of non-sustained supraventricular tachycardia, relative risk 3.02 (1.11-8.22). Thus, age of the patient, attenuated preoperative cardiac vagal modulation, ectopic supraventricular beats, and paroxysmal non-sustained supraventricular tachycardia are independent risk factors for the development of atrial fibrillation or flutter after coronary artery bypass surgery.


Assuntos
Fibrilação Atrial/etiologia , Ponte de Artéria Coronária/efeitos adversos , Taquicardia Atrial Ectópica/complicações , Fibrilação Atrial/prevenção & controle , Flutter Atrial/etiologia , Flutter Atrial/prevenção & controle , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Monitorização Fisiológica , Complicações Pós-Operatórias/prevenção & controle , Cuidados Pré-Operatórios , Estudos Prospectivos , Fatores de Risco , Taquicardia Atrial Ectópica/diagnóstico , Taquicardia Atrial Ectópica/fisiopatologia , Nervo Vago/fisiologia
15.
Ugeskr Laeger ; 158(8): 1068-72, 1996 Feb 19.
Artigo em Dinamarquês | MEDLINE | ID: mdl-8638339

RESUMO

The aim of the present study was to evaluate survival and therapy for ventricular tachyarrhythmia in patients treated with implantable cardioverter-defibrillator (ICD)-implantation at Skejby Hospital. Seventy-two patients, of which 54 were male, have received an ICD since 1989. Mean (range) age was 54 (16-74) years. Forty-nine (68%) had ischaemic heart disease. The patients were followed for a median (range) of 14 (1/2-50) months. Kaplan-Meyer plots are presented for total mortality, cardiac mortality, sudden cardiac mortality, appropriate therapy, and therapy for life-threatening tachyarrhythmia. After one, two and three years respectively, mortality was respectively 13, 27, and 32%, cardiac mortality was 5, 19, and 24%, sudden cardiac mortality was 3, 6, and 12%, cumulative incidence of appropriate therapy was 56, 66, and 90%, and cumulative incidence of therapy for life-threatening tachyarrhythmia was 19, 29 and 52%. It is concluded, that the majority of patients treated with an ICD developed ventricular tachyarrhythmia and had appropriate or lifesaving ICD-therapy during follow-up.


Assuntos
Desfibriladores Implantáveis , Taquicardia Ventricular/terapia , Adolescente , Adulto , Idoso , Dinamarca/epidemiologia , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Taquicardia Ventricular/mortalidade , Taquicardia Ventricular/fisiopatologia
16.
Ugeskr Laeger ; 156(40): 5817-23, 1994 Oct 03.
Artigo em Dinamarquês | MEDLINE | ID: mdl-7985270

RESUMO

Late potentials in the QRS complex can be detected with signal-averaged electrocardiography and are associated with delayed and disorganized ventricular activation. This article reviews the technique, describes the pathophysiological basis of late potentials, and assesses the prognostic value of late potentials for subsequent development of ventricular tachyarrhythmias and sudden cardiac death in postmyocardial infarction patients.


Assuntos
Infarto do Miocárdio/complicações , Taquicardia Ventricular/etiologia , Fatores Etários , Eletrocardiografia/métodos , Feminino , Humanos , Masculino , Infarto do Miocárdio/diagnóstico , Infarto do Miocárdio/fisiopatologia , Prognóstico , Fatores de Risco , Processamento de Sinais Assistido por Computador , Taquicardia Ventricular/diagnóstico , Taquicardia Ventricular/fisiopatologia , Fatores de Tempo
17.
BMJ ; 318(7184): 667; author reply 668, 1999 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-10215364
18.
Heart ; 95(5): 362-9, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19218262

RESUMO

There is a continuing controversy about the acceptable time-window for primary percutaneous coronary intervention (PPCI) in patients with ST-elevation myocardial infarction (STEMI). Recent American and European guidelines recommend PPCI if the delay in performing PPCI instead of administering fibrinolysis (PCI-related delay) is <60 min and the presentation delay is more than 3 h. Based on a review of the literature, this viewpoint recommends a revision of the guidelines. The evidence supports an acceptable PCI-related delay of 80-120 min and PPCI as the better reperfusion strategy also in the early incomers. Furthermore, the previous assumption that PPCI is less time-dependent than fibrinolysis is questioned. To maximise the number of patients with STEMI eligible for PPCI the optimal logistic may be to establish the diagnosis in the prehospital phase, to bypass local hospitals and re-route patients directly to catheterisation laboratories running 24/7.


Assuntos
Angioplastia Coronária com Balão/métodos , Fibrinolíticos/uso terapêutico , Infarto do Miocárdio/terapia , Guias de Prática Clínica como Assunto , Angiografia Coronária , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto , Encaminhamento e Consulta , Terapia Trombolítica , Fatores de Tempo
19.
Clin Auton Res ; 8(3): 165-71, 1998 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9651666

RESUMO

Low parasympathetic activity is associated with late potentials detected at a noise level of 0.4 microV in a signal-averaged electrocardiogram (SAECG) following myocardial infarction. In contrast, at a noise level of 0.2 microV, lowering parasympathetic activity influences late potential parameters in the opposite direction in healthy subjects. The aim of this study was to estimate the relationship between parasympathetic activity and the SAECG obtained at noise levels of 0.4 and 0.2 microV in healthy subjects. Two SAECG recordings in 10 healthy subjects were obtained at noise levels of 0.2 and 0.4 microV before and after parasympathetic blockade using atropine (1 mg). Signal-averaged QRS duration (SA-QRS), late potential duration (LPD) defined as duration of terminal signals below 40 microV, and root mean square voltage of the terminal 40 ms of the averaged QRS (RMS40) were measured. At a noise level of 0.2 microV SA-QRS reduced from 124 +/- 14 to 114 +/- 17 ms (P = 0.008), LPD from 37 +/- 10 to 28 +/- 14 ms (P = 0.01), and RMS40 increased from 26 +/- 22 to 41 +/- 25 microV (P = 0.006) during parasympathetic blockade compared to baseline values. At a noise level of 0.4 microV the SA-QRS (115 +/- 15 ms) and LPD (29 +/- 11 ms) were lower and the RMS40 (37 +/- 23 microV) was higher compared to the noise level 0.2 microV, and no systematic alterations of the three variables were found during parasympathetic blockade. The parasympathetic nervous system may induce a very low-amplitude late potential in the SAECG. The data suggest that parasympathetic activity and a low noise level may lead to a false late potential-positive SAECG in low arrhythmia risk subjects. Therefore, we recommend the use of a noise level of 0.4 microV or identification of high arrhythmia risk patients by late potential and low parasympathetic activity.


Assuntos
Eletrocardiografia/efeitos dos fármacos , Parassimpatolíticos/farmacologia , Adulto , Atropina/farmacologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Ruído/efeitos adversos , Fatores de Risco
20.
Eur Heart J ; 14(11): 1554-60, 1993 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-8299640

RESUMO

Alterations in the right ventricular function may or may not contribute to progressive cardiac dysfunction after left ventricular infarction. Ligation of the left coronary artery (LCAL) was lethal within 24 h for 25% of 100 rats, whereas none of 21 sham-operated rats died. No rats died during the following 4 weeks, after which the ischaemic area of the left ventricular wall appeared fibrotic and weighed 0.041% of the body weight. Simultaneously, the weight of the right ventricle increased from 0.037 to 0.072% of the body weight. The hypertrophied right papillary muscle had a depressed force of contraction and prolonged contraction and relaxation phases. Angiotensin converting enzyme inhibition (ACEI) started early (24 h) prevented hypertrophy and normalized the contractile pattern under basic conditions. However, isoprenaline stimulation revealed that the relaxation phase was still prolonged. Concentration-effect curves for Ca2+ indicated that the pathological relaxation observed in the hypertrophied muscles and during isoprenaline stimulation of myocardium in ACEI treated animals could be due to insufficient re-uptake of cytosolic Ca2+ by the sarcoplasmic reticulum. The results support the idea that the development of right ventricular hypertrophy may contribute to pathophysiological consequences of an infarct in the left ventricle. ACEI started after 24 h prevented hypertrophy, whereas ACEI started after 14 days did not. ACEI was unable to normalize completely the balance between energy demand and energy delivery.


Assuntos
Inibidores da Enzima Conversora de Angiotensina/farmacologia , Contração Miocárdica/fisiologia , Infarto do Miocárdio/fisiopatologia , Músculos Papilares/fisiopatologia , Função Ventricular Direita/fisiologia , Angiotensina II/sangue , Inibidores da Enzima Conversora de Angiotensina/uso terapêutico , Animais , Cardiomegalia/prevenção & controle , Masculino , Ratos , Ratos Wistar
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