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1.
Clin Radiol ; 72(4): 286-292, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28069158

RESUMO

AIM: To investigate changes in myocardial tissue volume during the cardiac cycle to verify the hypothesis of non-compressibility of the myocardium in healthy individuals (HI) as well as in patients with hypertrophic cardiomyopathy (HCM), dilated cardiomyopathy (DCM), and aortic stenosis (AS). MATERIALS AND METHODS: The study group included 30 HI, and patients with HCM (n=110), DCM (n=89), and AS (n=78). Left ventricular (LV) function, end-diastolic, and end-systolic volumes were calculated based on cardiac magnetic resonance imaging (CMR) for all participants. RESULTS: End-systolic myocardial volumes were higher than end-diastolic in both controls (91.2±26.6 versus 85.1±24.3 ml, p<0.001) and in all patient groups: HCM (214.3±81.6 versus 176±64.2 ml, p<0.01), DCM (128.4±43.1 versus 115.4±42.9 ml, p<0.001) and AS (155.1±37.1 versus 129.4±34.6 ml, p<0.001). HCM and AS patients had significantly higher systolic volume gain than HI (21.5±8.3 versus 10.6±6.3%, p<0.01 and 18.3±5.7 versus 10.6±6.3% p=0.013, respectively). Conversely, DCM patients had lesser increases in myocardial systolic volume than HCM patients (11.2±4.8% versus 21.5±8.3, p=0.01) and AS patients (11.2±4.8% versus 18.3±5.7, p=0.02). No differences were found in systolic volume gain between AS and HCM patients (p=ns) or between DCM patients and HI (p=ns). CONCLUSION: End-systolic myocardial volume was significantly higher than end-diastolic volume in all subsets of patients. The systolic volume gain was greater in individuals with hypertrophy than in those without.


Assuntos
Cardiomiopatia Dilatada/diagnóstico por imagem , Cardiomiopatia Hipertrófica/diagnóstico por imagem , Imageamento por Ressonância Magnética , Miocárdio/patologia , Adulto , Idoso , Cardiomiopatia Dilatada/patologia , Cardiomiopatia Hipertrófica/patologia , Feminino , Coração/diagnóstico por imagem , Humanos , Masculino , Tamanho do Órgão , Adulto Jovem
2.
Chaos ; 25(3): 033115, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25833437

RESUMO

Extraction of stochastic and deterministic components from empirical data-necessary for the reconstruction of the dynamics of the system-is discussed. We determine both components using the Kramers-Moyal expansion. In our earlier papers, we obtained large fluctuations in the magnitude of both terms for rare or extreme valued events in the data. Calculations for such events are burdened by an unsatisfactory quality of the statistics. In general, the method is sensitive to the binning procedure applied for the construction of histograms. Instead of the commonly used constant width of bins, we use here a constant number of counts for each bin. This approach-the fixed mass method-allows to include in the calculation events, which do not yield satisfactory statistics in the fixed bin width method. The method developed is general. To demonstrate its properties, here, we present the modified Kramers-Moyal expansion method and discuss its properties by the application of the fixed mass method to four representative heart rate variability recordings with different numbers of ectopic beats. These beats may be rare events as well as outlying, i.e., very small or very large heart cycle lengths. The properties of ectopic beats are important not only for medical diagnostic purposes but the occurrence of ectopic beats is a general example of the kind of variability that occurs in a signal with outliers. To show that the method is general, we also present results for two examples of data from very different areas of science: daily temperatures at a large European city and recordings of traffics on a highway. Using the fixed mass method, to assess the dynamics leading to the outlying events we studied the occurrence of higher order terms of the Kramers-Moyal expansion in the recordings. We found that the higher order terms of the Kramers-Moyal expansion are negligible for heart rate variability. This finding opens the possibility of the application of the Langevin equation to the whole range of empirical signals containing rare or outlying events. Note, however, that the higher order terms are non-negligible for the other data studied here and for it the Langevin equation is not applicable as a model.


Assuntos
Relógios Biológicos/fisiologia , Sistema de Condução Cardíaco/fisiologia , Frequência Cardíaca/fisiologia , Modelos Cardiovasculares , Dinâmica não Linear , Animais , Simulação por Computador , Humanos
3.
Physiol Meas ; 36(1): 163-75, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25514504

RESUMO

In recent years the number of arterial stenosis (AS) patients has grown rapidly and valvular disease is expected to be the next great epidemic. We studied a group of 385 arterial valve replacement (AVR) surgery patients, of whom 16 had died in the postoperational period (up to 30 d after the operation). Each patient had a heart rate variability (HRV) recording made prior to the operation in addition to a full set of medical diagnostics including echocardiography. We formed 16 age, sex, New York Heart Association (NYHA) class, and BMI adjusted control pairs for each person who died in the perioperative period. Our aim was to find indications of the risk from AVR surgery based on the medical data and HRV properties. Besides standard, linear HRV methods, we used indexes of time irreversibility introduced by Guzik (G%), Porta (P%), Ehlers (index E) and Hou (index D). In addition, we analyzed the multiscale multifractal properties of HRV calculating the Hurst surface. The nonlinear analysis methods show statistically significant indications of the risk of AVR surgery in an increase of multifractality and an increase of time irreversibility of the HRV measured prior to the operation.


Assuntos
Valva Aórtica/cirurgia , Implante de Prótese de Valva Cardíaca/efeitos adversos , Medição de Risco/métodos , Valva Aórtica/diagnóstico por imagem , Valva Aórtica/fisiopatologia , Estenose da Valva Aórtica/diagnóstico por imagem , Estenose da Valva Aórtica/mortalidade , Estenose da Valva Aórtica/fisiopatologia , Estenose da Valva Aórtica/cirurgia , Complicações do Diabetes/fisiopatologia , Feminino , Frequência Cardíaca , Humanos , Hipertensão/complicações , Hipertensão/fisiopatologia , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Dinâmica não Linear , Razão de Chances , Período Pós-Operatório , Risco , Índice de Gravidade de Doença , Ultrassonografia
5.
Pol Arch Med Wewn ; 106(1): 581-7, 2001 Jul.
Artigo em Polonês | MEDLINE | ID: mdl-11928569

RESUMO

UNLABELLED: Paroxysmal atrial fibrillation (PAF) is a frequent complication (10-60% of pts) after cardiac surgery. In our study we analyze the influence of clinical, echocardiographic and 24 h ecg parameters on the risk of postoperative PAF in 266 pts with aortic stenosis (88 women and 178 men; mean age 58 +/- 10). PAF was observed in 74 (28%) patients. Statistically significant factors of risk of PAF were (univariate analysis): age-relative risk 1.08 (1.04-1.11), history of PAF--4.3 (1.4-12.5), more than 100 supraventricular ectopic beats during 24 h ecg--2.9 (1.6-5.1), presence of SVT during 24 h ecg--2.6 (1.5-4.5) and presence of SVT > 140/min--relative risk 3.5 (1.8-6.7). Left atrium diameter and coronary artery bypass grafting during valve replacement had no impact on the risk of PAF. In multivariate analysis three factors remained significant--age, history of PAF and presence of SVT > 140/min during 24 h ecg. In discriminant analysis this model of 3 factors enabled the correct risk assessment in 72% of patients. CONCLUSIONS: 1. The factors that increase the risk of postoperative PAF in pts with aortic stenosis are: age, history of PAF and presence of SVT > 140/min during preoperative 24 h ecg. 2. Postoperative PAF is not related to left atrium diameter in this group of patients. 3. Coronary artery bypass grafting during aortic valve replacement does not increase the risk of PAF.


Assuntos
Estenose da Valva Aórtica/cirurgia , Fibrilação Atrial/etiologia , Implante de Prótese de Valva Cardíaca/efeitos adversos , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Ponte de Artéria Coronária , Eletrocardiografia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Fatores de Risco , Estatísticas não Paramétricas , Fatores de Tempo
6.
Przegl Lek ; 57(5): 262-5, 2000.
Artigo em Polonês | MEDLINE | ID: mdl-11057114

RESUMO

The quality of life in 114 patients with acquired heart valve disease 3 months after surgical treatment was estimated. The significant improvement of quality of life in the matter of physical, psychical and social factors after mitral, aortic and double valve replacement was noted. It was accompanied by increase of exercise capacity measured in 6-minute walk test and changing of NYHA functional classes. No correlation was found between age of patients, selected echocardiographic parameters and quality of life improvement.


Assuntos
Doenças das Valvas Cardíacas/cirurgia , Qualidade de Vida , Adulto , Idoso , Procedimentos Cirúrgicos Cardíacos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Período Pós-Operatório , Fatores de Tempo
7.
Przegl Lek ; 56(10): 656-9, 1999.
Artigo em Polonês | MEDLINE | ID: mdl-10695380

RESUMO

UNLABELLED: A mitral valve replacement without simultaneous correction of a concomitant tricuspid regurgitation aggravates remote postoperative results. Nowadays diagnostics of a degree of tricuspid regurgitation bases on semi-quantitative methods, which are not unequivocal criteria of a significant tricuspid insufficiency. The aim of the study was to investigate diagnostic usefulness of a radioisotopic method of determination significant tricuspid insufficiency. The study group consisted of 35 patients with rheumatic mitral valve disease and tricuspid regurgitation (30 females, 5 males) at a mean age of 55 years qualified for operative treatment. Physical and noninvasive examinations were performed in all patients: chest X-ray (relative heart volume--RHV) and echocardiographicy (tricuspid regurgitation and right ventricle pressure). Final determination of a significant tricuspid insufficiency based on intraoperative diagnosis. The radioisotopic method relies on first pass technique with a determination of a tricuspid regurgitation index (TRI) and a right ventricular ejection fraction. Intraoperatively the patients were divided into two groups: with significant tricuspid regurgitation--21 patients and without--14 patients. Statistically significant differences, considering clinical and echocardiographic assessment between the two groups were noticed. The TRI index did not differentiate two groups. Noninvasive parameters that could affect diagnosis of significant tricuspid regurgitation were proved by a logistic regression analysis. Among them the TRI Index could have a separate value. CONCLUSIONS: Presented radioisotopic method of determination a degree of tricuspid regurgitation with the new TRI Index is of value in diagnosing significant tricuspid insufficiency when assessed with other noninvasive parameters. Estimation of a clinical usefulness of the method needs further investigation and bigger study group.


Assuntos
Doenças das Valvas Cardíacas/complicações , Insuficiência da Valva Tricúspide/complicações , Insuficiência da Valva Tricúspide/diagnóstico por imagem , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valva Mitral/cirurgia , Cuidados Pré-Operatórios , Cintilografia , Cardiopatia Reumática/complicações , Insuficiência da Valva Tricúspide/cirurgia
8.
Pol Arch Med Wewn ; 102(3): 797-800, 1999 Sep.
Artigo em Polonês | MEDLINE | ID: mdl-10949887

RESUMO

We discuss the case of 49 years old woman with recurrent thrombosis of prosthetic mitral valve with ventricular fibrillation as the complication. For the first time thrombotic prosthetic valve Carbo Medics 33 had been removed and the new valve--Medtronic Hall 31 mm was implanted in the mitral position. After diagnosis of the repeated thrombosis on the replaced prosthetic valve, the patient refused the subsequent operation. The fully effective thrombolytic therapy was then performed. The patient was discharged from the Department and was asymptomatic 4 month follow-up.


Assuntos
Trombose Coronária , Próteses Valvulares Cardíacas/efeitos adversos , Valva Mitral , Fibrilação Ventricular/etiologia , Trombose Coronária/tratamento farmacológico , Trombose Coronária/etiologia , Trombose Coronária/cirurgia , Feminino , Fibrinolíticos/uso terapêutico , Humanos , Pessoa de Meia-Idade , Valva Mitral/cirurgia , Falha de Prótese , Recidiva , Terapia Trombolítica
9.
J Heart Valve Dis ; 7(5): 586-9, 1998 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9793861

RESUMO

BACKGROUND AND AIMS OF THE STUDY: The study was performed to establish the frequency of significant coronary artery stenosis (SCS) in patients with valvular heart disease (VHD), and in particular its correlation with the incidence of angina pectoris and presence of coronary risk factors. The need for coronary arteriography to be performed in all patients with VHD before surgery was also investigated. METHODS: Retrospective examinations were performed in 1292 patients with VHD (mean age 51 years) who underwent selective coronary angiography before surgery between 1982 and 1990. In each patient the presence of angina pectoris and the following risk factors were noted: cigarette smoking, systemic hypertension, family history of ischemic heart disease, elevated fasting serum lipids, history of diabetes mellitus and overweight. RESULTS: The incidence of SCS was 13%, was higher in patients with angina, and correlated significantly with coronary risk factors of smoking, hypertension, history of ischemic heart disease, elevated lipids and diabetes, but not with overweight. The incidence of SCS increased progressively with the number of coronary risk factors, from 2% in patients without risk factors, to 6% with one risk factor, and to 21% with two or more risk factors. SCS was not found in patients without coronary risk factors and without angina pectoris below 55 years of age. CONCLUSIONS: A statistically significant correlation was found between increasing numbers of coronary risk factors and significant coronary artery disease. These results suggest that coronary angiography may not be an obligatory diagnostic step before valve replacement in patients aged < 55 years who have neither risk factors nor angina pectoris.


Assuntos
Doença das Coronárias/epidemiologia , Doenças das Valvas Cardíacas/epidemiologia , Adulto , Distribuição por Idade , Angina Pectoris/epidemiologia , Angina Pectoris/etiologia , Distribuição de Qui-Quadrado , Comorbidade , Doença das Coronárias/etiologia , Feminino , Doenças das Valvas Cardíacas/diagnóstico , Humanos , Incidência , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Polônia/epidemiologia , Valor Preditivo dos Testes , Estudos Retrospectivos , Fatores de Risco , Distribuição por Sexo
11.
Pol Arch Med Wewn ; 100(1): 63-5, 1998 Jul.
Artigo em Polonês | MEDLINE | ID: mdl-10085716

RESUMO

A case of 48-year old patient, who developed anginal symptoms 3 months after aortic and mitral valves replacement was presented. The patient underwent coronary angiography, which revealed severe left main coronary stenosis. Successful surgery was done with grafting of left anterior descending and circumflex arteries. Opinions on etiology, diagnosis and management of this rare complication are discussed.


Assuntos
Angina Pectoris/etiologia , Valva Aórtica/cirurgia , Implante de Prótese de Valva Cardíaca/efeitos adversos , Valva Mitral/cirurgia , Angina Pectoris/diagnóstico por imagem , Angina Pectoris/cirurgia , Angiografia Coronária , Humanos , Doença Iatrogênica , Masculino , Pessoa de Meia-Idade , Reoperação
12.
Kardiol Pol ; 39(10): 259-63, 1993 Oct.
Artigo em Polonês | MEDLINE | ID: mdl-8246353

RESUMO

The aim of this study was to estimate coincidence of coronary artery disease (CAD) and rheumatic mitral valve disease in 264 patients treated in the National Institute of Cardiology (1976-1990). Severity of stenoses on coronary angiography with respect to age, sex, symptoms and risk factors were also estimated. Stenoses over 70% of artery lumen in relation to artery diameter before lesion and over 50% for left main coronary artery were stated as severe. There were 180 (68%) females and 84 (32%) males in the studied group; mean age was 52.5 year. Patients were divided into two groups: with angina--126 pts and without CAD symptoms--138 pts. 8 females (4%) had severe stenoses and 45 (25%) non-severe. Respectively 14 males (16.7%) had severe stenoses and 14 non-severe. Severe lesions were present in a group of females older than 50 years and in a group of males older than 45 years. Both in group with or without angina prevalence of coronary artery lesions was similar. Sensitivity and specificity of CAD clinical symptoms was low (less than 50%). Significantly more risk factors were present in pts with coronary stenoses than in pts free of CAD. No correlation between high pulmonary artery pressure and angina in patients without coronary stenoses occurred.


Assuntos
Doença das Coronárias/complicações , Estenose da Valva Mitral/complicações , Cardiopatia Reumática/complicações , Angiografia Coronária , Doença das Coronárias/diagnóstico por imagem , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco
13.
Pol Arch Med Wewn ; 89(4): 293-7, 1993 Apr.
Artigo em Polonês | MEDLINE | ID: mdl-8351229

RESUMO

The aim of the study was to analyze atrial natriuretic peptide (ANP) plasma level in patients with rheumatic mitral valve disease in correlation with NYHA functional class and selected hemodynamic parameters based on noninvasive diagnostic procedures. Echocardiographic (2-D, Doppler) and X-ray chest examination were performed to measure left atrium dimension, mitral gradient and relative heart volume (RHV). Control group consisted of 10 healthy subjects. ANP were measured (radioimmunoassay) in 35 patients before valve replacement. Mean values for ANP were significantly elevated in all patients compared to control group (p < 0.001). No significant difference between ANP secretion in pts with sinus rhythm (mean ANP level 25.3 +/- 6.9 pmol/l) and pts with atrial fibrillation (mean ANP level 26.7 +/- 7.6 pmol/l) occurred. Positive correlation between left atrium dimension and ANP level were found (r = 0.964) and also between RHV and ANP level (r = 0.9) and between NYHA class and ANP level (r = 0.63). The conclusion is that ANP secretion is elevated in all patients with heart failure due to mitral valve disease proportional to its stage.


Assuntos
Fator Natriurético Atrial/sangue , Insuficiência da Valva Mitral/sangue , Cardiopatia Reumática/sangue , Adulto , Idoso , Volume Cardíaco , Ecocardiografia Doppler , Feminino , Átrios do Coração/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Radiografia
14.
Kardiol Pol ; 33(4): 213-9, 1990 Apr.
Artigo em Polonês | MEDLINE | ID: mdl-2273717

RESUMO

Incidence of concomitant coronary disease and extent of coronary artery lesions were assessed in 250 patients with acquired post-rheumatic aortic valve disease treated between 1976 and 1986 in National Institute of Cardiology. Patients' age ranged from 30 to 72 years. Hemodynamic examination with selective coronarography were performed in patients with typical effort or rest angina pain, with electrographically documented myocardial infarction in the past and also in those without (CAD clinical symptoms, but older than 45 years. Patients were divided into two groups: with isolated or dominated aortic valve stenosis (139 patients) and with isolated or dominated aortic valve incompetence. Patients younger and older than 45 years were separately analyzed. Concomitant CAD was proved if at least one coronary artery stenosis was stated. Lesions degree was proportionally graded: stenosis more than 70%, between 50-70% and 20-50% of a vessel lumen in relation to its diameter before lesion. Data were analyzed using ICL ME 29 computer. Study results indicate, that symptoms of coronary failure were observed in 82.8% of patients with acquired aortic valve disease. In 37% of cases there were critical stenoses requiring simultaneous aortic valve replacement with coronary artery by-pass grafting. Severe coronary artery stenosis was stated in 45% of patients with dominated or isolated aortic valve incompetence, whereas only in 29.3% with dominated or isolated aortic valve stenosis. 88.5% of patients younger than 45 years nevertheless coronary failure symptoms had normal coronary arteries.


Assuntos
Insuficiência da Valva Aórtica/complicações , Estenose da Valva Aórtica/complicações , Doença das Coronárias/complicações , Adulto , Fatores Etários , Idoso , Angiografia Coronária , Doença das Coronárias/diagnóstico por imagem , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade
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