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3.
Clin Exp Rheumatol ; 21(2): 199-204, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12747274

RESUMO

BACKGROUND: Raynaud's phenomenon is often the first symptom and occurs eventually in more than 95% of patients with systemic sclerosis (SSc). Angiographic studies disclose narrowing and obstruction of the digital arteries, which on autopsy histologic study show prominent subintimal connective tissue proliferation without inflammation, as well as adventitial fibrosis. It is also known that primary cardiac problems include pericarditis, left ventricular or biventricular failure, serious supraventricular or ventricular arrhythmias emerge in patients with SSc. It is not known if these patients present hypertension or hypotension and which parameter of the ambulatory blood pressure may influence such a disease course. METHODS: A total of 85 subjects underwent clinical blood pressure (BP) readings, 24-hour ambulatory BP monitoring, left ventricular assessment by echocardiography and measurement of intima media thickness (IMT) of the right-left internal carotid arteries (RICA and LICA) and right-left common carotid arteries (RCCA and LCCA). The population consisted of 40 subjects with SSc according to the criteria of the American College of Rheumatology (SCL-group) who were not receiving any antihypertensive treatment and 45 healthy volunteers (control group). The two groups did not differ in age. RESULTS: Clinical systolic and diastolic blood pressure, clinical heart rate, mean 24 h systolic blood pressure, SD systolic blood pressure, mean 24 h diastolic blood pressure, SD 24 h diastolic blood pressure, mean 24 h heart rate, SD 24 h heart rate, pulse pressure 24 h, serum glucose, cholesterol, triglycerides, HDL, LDL, creatinine, urea, potassium and natrium did not statistically significant differ between the two groups. Furthermore, the left ventricular mass/BSA and IMT of both carotid arteries did not show a statistically significant difference between the groups. CONCLUSION: Systemic sclerosis is not associated with clinical blood pressure or the parameter of 24 h blood pressure monitoring.


Assuntos
Arteriosclerose/fisiopatologia , Hipertensão/fisiopatologia , Hipotensão/fisiopatologia , Escleroderma Sistêmico/fisiopatologia , Arteriosclerose/complicações , Monitorização Ambulatorial da Pressão Arterial , Artérias Carótidas/diagnóstico por imagem , Ecocardiografia , Ventrículos do Coração/diagnóstico por imagem , Humanos , Hipertensão/complicações , Hipotensão/complicações , Escleroderma Sistêmico/complicações
4.
Int J Artif Organs ; 24(7): 478-83, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11510920

RESUMO

Data concerning the effect of arterial compliance (AC) on hemodynamics during intraaortic balloon counterpulsation (IABC) are lacking. This study examines the effect of AC on acute hemodynamics induced by IABC in 15 patients with post-infarction cardiogenic shock. AC was estimated by aortic pulse wave analysis using the reflection time index (RTI). Measurements were obtained once per day during IABC. The % reduction in systolic aortic pressure (ASAP), end-diastolic aortic pressure (AEDAP) and the peak aortic diastolic augmentation (PADA) were used as performance indices of IABC; 107 sets of measurements were obtained. Multivariate analysis indicated an independent association of each IABC performance index with AC (p<0.05). A high AC group (RTI< or =20.6%, n=40) and a low AC group (RTI>20.6%, n=67) were obtained. DeltaSAP deltaEDAP and PADA were significantly higher in the low AC group by almost 75%, 54.6% and 11.3% (p<0.03), while arterial blood pressure did not significantly differ. Arterial compliance is an independent factor affecting hemodynamics during IABC. RTI values higher than 20.6% may predict a better acute hemodynamic response to IABC.


Assuntos
Aorta/fisiologia , Complacência (Medida de Distensibilidade) , Hemodinâmica , Idoso , Aorta Torácica/fisiologia , Feminino , Artéria Femoral/fisiologia , Humanos , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Valor Preditivo dos Testes
5.
Pacing Clin Electrophysiol ; 23(7): 1127-32, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10914369

RESUMO

We hypothesized that the variance of P wave duration (P variance) in the 12-lead ECG could reflect the spatial dispersion of P wave duration due to inhomogeneous and delayed propagation of sinus impulses in the atria, and moreover could present better reproducibility than maximum P wave duration and P wave dispersion that have already been used for the prediction of idiopathic paroxysmal AF. We also tested a semiautomated PC-based method to improve the accuracy and reproducibility of P wave measurements. A 12-lead ECG was obtained from 60 patients with idiopathic paroxysmal AF and from 50 healthy controls. All ECGs were analyzed manually using magnifying lens and calipers, while 20 randomly selected ones were scanned and analyzed on screen using common commercial software. P maximum, P dispersion, and P variance were all significantly higher in patients with paroxysmal AF than in controls. A P maximum value of 110 ms, a P dispersion value of 40 ms, and a P variance value of 120 ms2 separated patients from controls with a sensitivity of 88%, 83%, and 80%, respectively and a specificity of 75%, 85%, and 74%, respectively. The reproducibility of P variance was higher compared to P dispersion and P maximum. Finally, the PC-based method significantly increased accuracy and reproducibility of P wave measurements. Thus, the variance of P wave duration could be a useful ECG marker for the prediction of paroxysmal idiopathic AF and the use of PC-based methods may enhance the accurate measuring of P wave duration on the ECG.


Assuntos
Fibrilação Atrial/diagnóstico , Eletrocardiografia , Fibrilação Atrial/diagnóstico por imagem , Fibrilação Atrial/fisiopatologia , Estudos de Casos e Controles , Ecocardiografia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Distribuição Aleatória , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
6.
Pacing Clin Electrophysiol ; 23(3): 352-8, 2000 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10750136

RESUMO

Patients with frequent episodes of paroxysmal atrial fibrillation (AF) are prone to develop permanent AF and have an increased thromboembolic risk. We have previously shown that P wave dispersion (P dispersion), defined as the difference between the maximum and the minimum P wave duration, and maximum P wave duration (P maximum) can distinguish patients with paroxysmal lone AF. The ability of those ECG markers and of other clinical and ECG variables to detect patients at risk for recurrent AF was tested in 88 patients, aged 64 +/- 12 years. All patients had a history of symptomatic episodes of AF during the last 2 years and had not previously received any antiarrhythmic prophylaxis. P maximum and P dispersion were calculated from a 12-lead surface ECG recorded in all patients during sinus rhythm. A computerized ECG system was used and P maximum and P dispersion were calculated on screen from the averaged complexes of all 12 leads. Age (P = 0.01), history of organic heart disease (P = 0.03), P maximum (P < 0.001), minimum P wave duration (P = 0.05), and P dispersion (P < 0.001) were found to be significant univariate predictors of recurrent AF, whereas only P maximum (P < 0.001) and age (P = 0.037) remained significant independent predictors of frequent AF paroxysms in the multivariate analysis. It is concluded that advanced age and prolonged P wave duration may be used as predictors of frequently relapsing AF. Therefore, simple AF predictors exist that could possibly distinguish the patients in whom prophylaxis with antiarrhythmic medicines should be instituted.


Assuntos
Fibrilação Atrial/diagnóstico , Eletrocardiografia , Adulto , Idoso , Idoso de 80 Anos ou mais , Fibrilação Atrial/diagnóstico por imagem , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Recidiva , Ultrassonografia
7.
Pacing Clin Electrophysiol ; 22(11): 1640-7, 1999 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-10598968

RESUMO

P wave dispersion (P dispersion), defined as the difference between the maximum and the minimum P wave duration, and maximum P wave duration (P maximum) are electrocardiographic (ECG) markers that have been used to evaluate the discontinuous propagation of sinus impulses and the prolongation of atrial conduction time, respectively. To study the effects of myocardial ischemia on P dispersion and P maximum, 95 patients with coronary artery disease (CAD) and typical angina pectoris and 15 controls with angina like symptoms underwent 12-lead surface ECG during and after the relief of pain. During pain and during the asymptomatic period, P maximum and P dispersion were calculated from the averaged complexes of all 12 leads. P dispersion increased significantly during spontaneous angina (45+/-17 ms) compared to the asymptomatic period (40+/-15 ms), P < 0.001 only in the patient group. Both P maximum and P dispersion showed higher values during angina in those patients who developed diffuse ischemia, as estimated with ST segment changes in multiple ECG leads. P dispersion showed higher values during the anginal episode in patients with left ventricular dysfunction, independently of the presence of a previous myocardial infarction. Atrial conduction abnormalities, as estimated with P maximum and particularly P dispersion, are significantly influenced by myocardial ischemia in patients with CAD and spontaneous angina.


Assuntos
Angina Pectoris/fisiopatologia , Eletrocardiografia , Isquemia Miocárdica/fisiopatologia , Adulto , Idoso , Angina Pectoris/diagnóstico , Nó Atrioventricular/fisiopatologia , Feminino , Átrios do Coração/fisiopatologia , Ventrículos do Coração/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/diagnóstico , Infarto do Miocárdio/fisiopatologia , Isquemia Miocárdica/diagnóstico , Recidiva , Nó Sinoatrial/fisiopatologia , Disfunção Ventricular Esquerda/diagnóstico , Disfunção Ventricular Esquerda/fisiopatologia
8.
J Hypertens ; 17(10): 1463-70, 1999 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-10526908

RESUMO

OBJECTIVE AND METHODS: To determine whether hypertensive patients at risk for paroxysmal atrial fibrillation (AF) could be detected while in sinus rhythm, a computer-based 12-lead surface electrocardiogram was recorded in 50 hypertensive patients with history of paroxysmal AF (group A) and in 60 hypertensive patients without history of AF (group B). The maximum P-wave duration (P(maximum)), the minimum P-wave duration (P(minimum)), P-wave dispersion (Pdispersion = Pmaximum Pminimum), adjusted P-wave dispersion (APdispersion = Pdispersion/square root of the number of measurable leads), mean P-wave duration (mean P) and the standard deviation of the P-wave duration in all measured leads (SDP) were calculated. RESULTS: Pdispersion, APdispersion and SDP were significantly higher in group A than in group B (Pdispersion, 52 +/- 19 versus 41 +/- 15 ms, P< 0.001; APdispersion, 15.2 +/- 5.5 versus 11.9 +/- 4.6 ms, P< 0.001; SDP, 16 +/- 5 versus 13 +/- 5 ms, P < 0.001). P(minimum), mean P and left ventricle ejection fraction (LVEF) were significantly lower in group A than in group B (Pminimum, 79 +/- 18 versus 91 +/- 13 ms, P < 0.001; mean P, 108 +/- 18 versus 116 +/- 13 ms, P= 0.005; LVEF, 64 +/- 5 versus 69 +/- 8%, P< 0.001). Pminimum, Pdispersion, mean P, SDP, APdispersion and LVEF were found to be significant univariate predictors of paroxysmal AF, whereas only Pminimum (P< 0.001) remained a significant independent predictor of paroxysmal AF in the multivariate analysis. CONCLUSION: Hypertensive patients at risk for paroxysmal AF could be detected while in sinus rhythm by computer-assisted electrocardiographic P-wave analysis.


Assuntos
Fibrilação Atrial/fisiopatologia , Eletrocardiografia , Hipertensão/fisiopatologia , Idoso , Fibrilação Atrial/etiologia , Feminino , Humanos , Hipertensão/complicações , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Risco
9.
Clin Cardiol ; 21(8): 585-90, 1998 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9702386

RESUMO

BACKGROUND: Heart rate variability (HRV) analysis is problematic during maximal treadmill exercise testing (ET) due to rapidly changing heart rate. HYPOTHESIS: The aim of this study was to assess HRV spectral components during treadmill ET in patients with coronary artery disease (CAD) and in healthy controls, and to search for possible differences between the two groups. METHODS: Thirty patients with CAD and 30 age-matched healthy controls underwent symptom-limited ET and continuous electrocardiographic monitoring. For adequate assessment of HRV during maximal ET, we calculated the HRV measures [normalized units (NU)]--low-frequency (0.040-0.150 Hz) power (LF), high-frequency (0.150-0.400 Hz) power (HF), and the LF/HF ratio--from all the sequential stages of the ET with limited changes (20 beats/min) in heart rate (stress 80-100, 100-120, 120-140, 140-160, 160-180/recovery 180-160, 160-140, 140-120, 120-100, 100-80). RESULTS: Both LF and HF were found to decrease gradually during ET and to increase during the recovery period in both patients and controls (p < 0.001). LF values were higher during the recovery period than during the respective stages of exercise time in both patients and controls, and LF/HF ratio was higher during recovery in patients only. CONCLUSIONS: During maximal ET (1) vagal tone withdraws during the exercise time and increases during the recovery period; (2) the sympathetic activity predominates during the recovery period, especially in patients with CAD and exercise-induced myocardial ischemia. This finding raises the possibility of ischemia-induced cardiocardiac sympathetic excitatory reflexes.


Assuntos
Doença das Coronárias/diagnóstico , Isquemia Miocárdica/fisiopatologia , Reflexo/fisiologia , Nervo Vago/fisiopatologia , Estudos de Casos e Controles , Doença das Coronárias/fisiopatologia , Eletrocardiografia , Eletrocardiografia Ambulatorial , Teste de Esforço , Feminino , Frequência Cardíaca/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade
10.
Am Heart J ; 135(5 Pt 1): 733-8, 1998 May.
Artigo em Inglês | MEDLINE | ID: mdl-9588401

RESUMO

BACKGROUND: The prolongation of intraatrial and interatrial conduction time and the inhomogeneous propagation of sinus impulses are well known electrophysiologic characteristics in patients with paroxysmal atrial fibrillation (PAF). METHODS: To search for possible electrocardiographic markers that could serve as predictors of idiopathic PAF, we measured the maximum P-wave duration (P maximum) and the difference between the maximum and the minimum P-wave duration (P dispersion) from the 12-lead surface electrocardiogram of 60 patients with a history of idiopathic PAF and 40 age-matched healthy control subjects. RESULTS: P maximum and P dispersion were found to be significantly higher in patients with idiopathic PAF than in control subjects. A P maximum value of 110 msec and a P dispersion value of 40 msec separated patients from control subjects, with a sensitivity of 88% and 83% and a specificity of 75% and 85%, respectively. CONCLUSIONS: P maximum and P dispersion are simple electrocardiographic markers that could be used for the prediction of idiopathic PAF.


Assuntos
Fibrilação Atrial/diagnóstico , Eletrocardiografia , Taquicardia Paroxística/diagnóstico , Adulto , Idoso , Anisotropia , Fibrilação Atrial/etiologia , Fibrilação Atrial/fisiopatologia , Feminino , Átrios do Coração/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Valores de Referência , Processamento de Sinais Assistido por Computador , Taquicardia Paroxística/etiologia , Taquicardia Paroxística/fisiopatologia
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