RESUMEN
Intraventricular septum rupture is a rare mechanic complication of myocardial infarction associated with high mortality. This case describes STEMI in recovered patient after COVID 19 associated pneumonia, which was complicated by ventricular septum rupture followed by cardiogenic shock. It was managed by percutaneous occluder implantation. The procedure was complicated by right ventricular wall rupture. Postmortem examination of myocardium showed the signs of inflammation infiltrate and myocyte necrosis, according to histopathological Dallas criteria diagnosis of COVID-19 associated myocarditis was established. The COVID-19 pandemic has contributed to increasing cardiovascular mortality. This is typically attributed to diminishing resources for timely and appropriate medical care, and patients' late presentations for fear of contracting the infection. Cardiovascular complication of COVID-19 may be another contributing factor. Further research is needed to improve our understanding of the mechanisms and long-term sequelae of myocardium damage in COVID-19, to optimize treatment strategy and subsequent follow-up in such patients.
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COVID-19 , Infarto del Miocardio , Miocarditis , Tabique Interventricular , Humanos , Miocarditis/etiología , Miocarditis/complicaciones , Pandemias , COVID-19/complicaciones , COVID-19/diagnóstico , Infarto del Miocardio/complicacionesRESUMEN
Aim To develop a new, modified protocol for transesophageal atrial electric stimulation (TEAES), which would significantly enhance the diagnostic value of stress echocardiography and reduce the duration of the test in patients with ischemic heart disease (IHD).Material and methods This study included 101 patients (80 men and 21 women aged 55±9 years) with suspected or documented diagnosis of IHD who were divided into two homogenous groups. Group 1 (51 patients) underwent stress echocardiography (stress-EchoCG) according to a standard protocol (SP) for TEAES and group 2 (50 patients), underwent stress-EchoCG according to a modified protocol (MP). In addition to stress-EchoCG with TEAES, selective coronary angiography was performed for all patients. The development of the new method for evaluating occult coronary insufficiency was based on comparison of SP and MP for TEAES with stress-EchoCG with data of coronary angiography.Results In both groups, significant differences in values of systolic and diastolic blood pressure were absent. However, the values of achieved heart rate were significantly different: 141±11 (TEAES SP) and 155±10 (TEAES MP) bpm (p=0.01). There was also a difference in the duration of the TEAES protocols: 15±3 and 5±2 min, respectively (p=0.006). The use of the modified TEAES protocol for detecting transient disorders of left ventricular myocardial local contractility increased the sensitivity, specificity and accuracy of the test from 76â%, 87â%, and 80â% to 83â%, 92â%, and 86â%, respectively. The most significant differences were found in the area supplied by the circumflex artery: the SP and MP sensitivities were 63â% and 75â%, respectively (p<0.05) and the SP and MP accuracies were 81â% and 90â%, respectively (p<0.05).Conclusion Evaluation of occult coronary insufficiency by stress-EchoCG with the TEAES MP as compared to the TEAES SP provides a gentler procedure regimen for the patient due to a shorter duration of the test and at the same time improves the diagnostic significance of this method in IHD patients.
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Enfermedad Coronaria , Isquemia Miocárdica , Angiografía Coronaria , Ecocardiografía de Estrés , Prueba de Esfuerzo , Femenino , Atrios Cardíacos , Humanos , Masculino , Persona de Mediana Edad , Isquemia Miocárdica/diagnóstico , Sensibilidad y EspecificidadRESUMEN
AIM: To compare diagnostic value between standard stress-echocardiography and myocardial contrast stress echocardiography in detection of myocardial ischemia in patients with different severity of coronary artery stenoses. MATERIALS AND METHODS: Myocardial contrast stress-echocardiography and standard stress-echocardiography were performed in 38 patients with coronary artery stenoses over 50% by angiography. Of all lesions 39 were intermediate (5075%) and 33 over 75% stenoses. Fractional flow reserve (FFR) was measured in 12 coronary arteries. During myocardial contrast stress-echocardiography wall motion and myocardial perfusion was assessed. RESULTS: Adequate visualisation increased from 81.6% in unenhanced segments to 96.1% in contrast-enhanced segments. The sensitivity, specificity, and diagnostic accuracy of standard stress-echocardiography and myocardial contrast stress-echocardiography in intermediate (5075%) coronary stenoses were 44%, 83%, 56% and 56%, 94% и 64% respectively compare to angiography. Taking into account the 12 arteries with evaluated FFR, these parameters increased to 52%, 93% и 65% in standard stress-echocardiography and to 68%, 100% and 75% in myocardial contrast stress-echocardiography. In coronary stenoses over 75% the sensitivity, specificity, and diagnostic accuracy of standard stress-echocardiography and myocardial contrast stress-echocardiography were 78%, 88%, 80% and 86%, 100%, 92% respectively Conclusion. Use of contrast-enhanced stress-echorardiography significantly increased the diagnostic value of this method by improving endocardial border visualization and possibilities of myocardial perfusion assessment.
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Estenosis Coronaria , Reserva del Flujo Fraccional Miocárdico , Isquemia Miocárdica , Angiografía Coronaria , Ecocardiografía , Ecocardiografía de Estrés , Humanos , Sensibilidad y EspecificidadRESUMEN
AIM: The study was to assess the deformation properties of the left ventricle (LV) myocardium in patients with breast cancer initially and after anthracycline chemotherapy according to 2D and 3D speckle-tracking echocardiography (STE). MATERIAL AND METHODS: the study included 99 patients with triple negative breast cancer with hypertensionandnormotension. All patients underwent standard transthoracic echocardiography with assessment of systolic function of the LV. To assess the indicator of global longitudinal strain (GLS), as a marker of cardiotoxicity, STE was used in two-and three-dimensional modes. In the three-dimensional STE mode, a new strain parameter, the global area strain (GAS) was evaluated. RESULTS: The study showed that in patients with breast cancer for a more accurate assessment of LV systolic function (ejection fraction) it is advisable to use 3D-echocardiography. A comparative analysis revealed statistically significantly lower values of the GLS according to the three-dimensional mode of STE compared to two-dimensional. The study also evaluated a new strain parameter GAS (%). In patients with breast cancer during ROC analysis with a value of -14.0, the GAS indicator for the development of subclinical cardiotoxicity showed a sensitivity of 81.5% and a specificity of 73.3%. Сonclusion.the advantage of the STE in the three-dimensional mode, in contrast to the two-dimensional mode, is the simultaneous and more accurate assessment of LVEF. The value of the additional parameter of LV deformation the area of deformation requires further study.
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Neoplasias de la Mama , Disfunción Ventricular Izquierda , Neoplasias de la Mama/tratamiento farmacológico , Cardiotoxicidad/diagnóstico por imagen , Ecocardiografía , Humanos , Reproducibilidad de los Resultados , Disfunción Ventricular Izquierda/diagnóstico , Disfunción Ventricular Izquierda/diagnóstico por imagen , Función Ventricular IzquierdaRESUMEN
The presented clinical observation demonstrates the diagnostic capabilities of cardiac volumetric computed tomography (CT) with a pharmacological test by a vasodilator adenosine triphosphate (ATP) in the simultaneous assessment of coronary anatomy and changes in left ventricular myocardial perfusion (LV) in a patient with painless myocardial ischemia and coronary atherosclerosis. A 68-year-old patient with coronary heart disease (CHD) and atherosclerotic changes in the coronary arteries underwent cardiac volumetric CT in combination with a ATP pharmacological test. The study was performed on a Aquilion ONE 640 Vision Edition computer tomograph (Toshiba, Japan). Assessment of LV myocardial perfusion was carried out in comparison with other clinical, laboratory and instrumental examination methods. The results of clinical and instrumental examination of a patient with a low pre-test probability of coronary heart disease are presented. From the standpoint of modern recommendations on stable coronary heart disease, false-negative results of single-photon emission computed tomography of the heart and stress-echocardiography are discussed. Clinical observation demonstrates the feasibility of diagnosing LV myocardial ischemia by cardiac volumetric CT combined with ATP pharmacological test, confirmed by an invasive determination of the fractional flow reserve. The given clinical example represents the advantage of cardiac volumetric CT, combined with the ATP pharmacological test, as a method for visualizing LV myocardial perfusion in detecting myocardial ischemia.
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Aterosclerosis , Enfermedad de la Arteria Coronaria , Isquemia Miocárdica , Imagen de Perfusión Miocárdica , Adenosina Trifosfato , Anciano , Tomografía Computarizada de Haz Cónico , Angiografía Coronaria , Vasos Coronarios , Humanos , Valor Predictivo de las Pruebas , Tomografía Computarizada de Emisión de Fotón ÚnicoRESUMEN
AIM: To identify the features of myocardial scar and fibrosis associated with the occurrence of malignant ventricular tachyarrhythmias (VTs) in high-risk patients with ischemic (ICMP) and non-ischemic cardiomyopathy (NICMP). MATERIALS AND METHODS: This prospective study included 50 patients (41 men, 9 women), age = 60 ± 13 years, 30 patients of them with ICMP and 20 patients with NICMP, who underwent echocardiography (Echo) and contrast magnetic resonance imaging (MRI) of the heart followed by implantation of cardioverter-defibrillators (ICD) or resynchronizing devices with defibrillator (CPTD) to prevent sudden cardiac death. RESULTS: Sustained VTs were reported in 20/30 (67%) patients with ICMP and in 5/20 (25%) patients with NICMP on follow-up [26 (22-37) months]. Successive univariate and ROC-analyses of Echo and MRI-indices between patients with and without recurrence of VTs found different results for ICMP and NICMP patients groups. In ICMP patients the VTs were associated with wide transmural fibrosis on contrast MRI that covered 3 or more segments of left ventricular. These segments were preferably localized in the middle parts of the inferior and inferolateral segments of the left ventricle. The independent predictors of VTs in NICMP patients were non-transmural fibrosis at 4.5% of the left ventricular mass by contrast MRI as well as low left ventricular ejection fraction (less than 26%) by Echo. CONCLUSION: To determine the indications for implantation of the ICD and CRTD for primary prevention of sudden cardiac death, it is advisable to take into account not only the value of ejection fraction of left ventricular, but also the features of the fibrosis of the left ventricle by contrast MRI of the heart.
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Terapia de Resincronización Cardíaca/métodos , Cardiomiopatías , Muerte Súbita Cardíaca , Desfibriladores Implantables , Ventrículos Cardíacos , Taquicardia Ventricular , Anciano , Cardiomiopatías/complicaciones , Cardiomiopatías/diagnóstico , Cardiomiopatías/etiología , Muerte Súbita Cardíaca/etiología , Muerte Súbita Cardíaca/prevención & control , Ecocardiografía/métodos , Femenino , Fibrosis , Ventrículos Cardíacos/diagnóstico por imagen , Ventrículos Cardíacos/patología , Humanos , Imagen por Resonancia Cinemagnética/métodos , Masculino , Persona de Mediana Edad , Pronóstico , Estudios Prospectivos , Medición de Riesgo/métodos , Federación de Rusia , Taquicardia Ventricular/diagnóstico , Taquicardia Ventricular/etiología , Taquicardia Ventricular/prevención & control , Función Ventricular IzquierdaRESUMEN
AIM: To assess the value of the complex analysis of electrocardiographic (ECG) variants and echocardiographic (echo) manifestation of left bundle branch block (LBBB) in predicting the success of cardiac resynchronization therapy (CRT). MATERIALS AND METHODS: The study included 39 patients (mean age 61.49±9.0 years) on sinus rhythm with LBBB, QRS duration ≥130 ms, left ventricular ejection fraction (LVEF) ≤35%, heart failure (HF) NYHA II-IV despite optimal pharmacological therapy during 3 month. All patients had undergone CRT-D implantation. Depending on presence or absence of ECG-criteria, proposed by D.G. Strauss et al., patients were divided into 2 groups: 1 group - strict LBBB, proposed by D.G. Strauss et al. (n=29) and 2 group - other patients (n=10). In addition to standard echocardiography, global longitudinal 2-dimensional strain (GLS) and LBBB contraction pattern have been performed initially and in 6 months after implantation. Response to CRT was defined as decrease in LV end-systolic volume by >15% after 6 months of follow-up. RESULTS: Typical LBBB echo contraction pattern was detected in 25 patients (64% of all included). These patients had more pronounced longitudinal dissynchrony and a more expressed global longitudinal strain before CPT-D implantation (p<0.05). 27 patients (69% of all included) were included in the "response" group, the remaining 12 patients (31% of all included) - the "non-response" group. In the "response" group the morphology of the QRS complex was significantly more likely to meet the criteria, proposed by D.G. Strauss et al., than other variants (23 vs. 6, respectively, p=0.02), and the echo contraction pattern of this patients more often corresponded to "typical" LBBB (24 vs. 1, p=0.001). All patients, who had the ECG criteria, proposed by D.G. Strauss et al., and echo "typical" LBBB contraction pattern, responded on CPT. Moreover, the proportion of these patients in the "response" group was rather high - 81.5% (22 of 27 patients). CONCLUSION: ECG criteria LBBB, proposed by D.G. Strauss et al., identify patients with delayed transseptal interventricular conduction due to complete LBBB, what is a good target for CPT. Evaluation of the echo contraction pattern based on the definition of longitudinal myocardial deformation by means of a two-dimensional strand technology allows predicting the success of CPT in patients with LBBB. Patients with «typical¼ LBBB contraction pattern show more pronounced global longitudinal strain and larger longitudinal dissynchrony compared with other patients, and it explains their better response to CPT. Complex analysis of strict LBBB ECG criteria and echo contraction pattern are promising parameters in predicting beneficial response to CRT in patients with HF.
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Bloqueo de Rama , Terapia de Resincronización Cardíaca , Electrocardiografía , Insuficiencia Cardíaca , Anciano , Bloqueo de Rama/fisiopatología , Bloqueo de Rama/terapia , Ecocardiografía , Humanos , Persona de Mediana Edad , Volumen Sistólico , Resultado del TratamientoRESUMEN
AIM: to compare noninfarct-related lesions in patients with acute myocardial infarction (MI) with culprit and non-culprit lesions in patients with stable angina pectoris (SAP) using intravascular ultrasound virtual histology (VH-IVUS). MATERIAL AND METHODS: Overall 70 patients were enrolled: 38 with ST elevation (STE) MI and 32 with stable angina pectoris (SAP). All patients underwent three-vessel coronary angiography and gray-scale and VH-IVUS after percutaneous coronary intervention (PCI) of infarct-related lesion in STEMI or culprit lesion in SAP. RESULTS: A total of 130 plaques were examined: 70 in patients with STEMI and 60 in patients with SAP. Noninfarct-related lesions in acute MI compared with non-culprit lesions in SAP had significantly larger plaque burden and plaque volume, smaller minimum lumen area, and more positive remodeling. STEMI, hyperlipidemia, plaque burden, and hypertension were independent predictors of unstable plaques.
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Angina Estable/diagnóstico por imagen , Vasos Coronarios/diagnóstico por imagen , Infarto del Miocardio/diagnóstico por imagen , Placa Aterosclerótica/diagnóstico por imagen , Ultrasonografía Intervencional/métodos , Diagnóstico Diferencial , Electrocardiografía , Femenino , Humanos , Masculino , Persona de Mediana Edad , Infarto del Miocardio/cirugía , Intervención Coronaria Percutánea , Reproducibilidad de los ResultadosRESUMEN
AIM: to compare noninfarct-related lesions in patients with acute myocardial infarction (MI) with culprit and non-culprit lesions in patients with stable angina pectoris (SAP) using intravascular ultrasound virtual histology (VH-IVUS). MATERIAL AND METHODS: Overall 70 patients were enrolled: 38 with ST elevation (STE) MI and 32 with stable angina pectoris (SAP). All patients underwent three-vessel coronary angiography and gray-scale and VH-IVUS after percutaneous coronary intervention (PCI) of infarct-related lesion in STEMI or culprit lesion in SAP.
RESUMEN
Chronic heart failure (CHF) - a widely spread manifestation of various forms of heart diseases - is characterized by high mortality. Prognosis is especially unfavorable in patients with wide QRS complex. Method of resynchronizing therapy was elaborated for the treatment of this group of patients in addition of medical therapy. Its efficacy for improvement of clinical course and prognosis of CHF was demonstrated in a number of randomized controlled trials. However according to some data in 30-45% of cases application of the method is associated with no clinical improvement or reversal of cardiac remodeling when standard criteria (left ventricular ejection fraction less or equal 35%, QRS 120-150 ms, functional class II-IV) are used for patients selection. In this review we consider possibilities of various methods of selection of patients providing maximal probability of efficacy. We also present analysis of techniques of detection of implantation site of left ventricular lead and various tactics of management of patients after implantation of biventricular pacemaker.
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Dispositivos de Terapia de Resincronización Cardíaca , Terapia de Resincronización Cardíaca/métodos , Insuficiencia Cardíaca , Manejo de la Enfermedad , Electrocardiografía/métodos , Insuficiencia Cardíaca/diagnóstico , Insuficiencia Cardíaca/fisiopatología , Insuficiencia Cardíaca/terapia , Humanos , Evaluación de Resultado en la Atención de Salud , Selección de Paciente , Pronóstico , Ensayos Clínicos Controlados Aleatorios como Asunto , Volumen Sistólico , Función Ventricular IzquierdaRESUMEN
Aim of the study was to assess effects of cardiac shock wave therapy (CSWT) in patients with coronary artery disease (CAD) with refractory stable angina pectoris. Seventeen CAD patients with refractory II-IV class angina (3 women and 14 men, mean age 67.4+/-8.6 years) received the course of 9 procedures of CSWT. All patients had I-III New York Heart Association (NYHA) class congestive heart failure. Before and after CSWT medical examination with life quality assessment by means of the Minnesota Living Questionnaire, echocardiography, veloergometry, myocardial perfusion imaging with single-photon emission computed tomography (SPECT) using 99M-Tc-methyl-iodine-benzyl-guanydin (MIBG) and Holter ECG monitoring was performed. The dynamics of pro-angiogenic factors (VEGF, HGF, FGF-) were also measured by ELISA, and of brain natriuretic peptide (Nt-proBNP) by the electrochemoluminescence method. Most patients (80%) had significant life quality (<0.01) and myocardial perfusion improvement. Episodes of angina pectoris and nitrate intake were more than twice decreased. There was a significant increase in exercise tolerance (p<0.01). Holter ECG monitoring showed decreasing of an average heart rate (p<0.02); no worsening of previous cardiac arrhythmias was observed. The significant (p<0.05) decreases in plasma Nt-proBNP and increases in VEGF concentration were revealed after CSWT. CSWT procedures were well tolerated. The results of our study confirm high effectiveness and safety of CSWT in complex treatment of patients with CAD, resistant angina pectoris, including patients after myocardial revascularization and with heart failure.
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Isquemia Miocárdica/terapia , Terapia por Ondas Cortas/métodos , Anciano , Angiografía Coronaria , Electrocardiografía Ambulatoria , Femenino , Humanos , Masculino , Isquemia Miocárdica/diagnóstico , Tomografía Computarizada de Emisión de Fotón Único , Resultado del TratamientoRESUMEN
This paper describes the clinical case - anterior myocardial infarction after blunt chest trauma in a 25-year-old man.
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Electrocardiografía , Infarto del Miocardio/etiología , Traumatismos Torácicos/complicaciones , Heridas no Penetrantes/complicaciones , Adulto , Angiografía Coronaria , Diagnóstico Diferencial , Prueba de Esfuerzo , Humanos , Masculino , Infarto del Miocardio/diagnóstico , Traumatismos Torácicos/diagnóstico , Tomografía Computarizada de Emisión , Heridas no Penetrantes/diagnósticoRESUMEN
UNLABELLED: In our study we compared effect of cardiac resynchronization therapy (CRT) in chronic heart failure (CHF) patients with permanent atrial fibrillation (AF) and patients with sinus rhythm. Special feature of our work was that patients with permanent atrial fibrillation didnt have obligatory ablation of atrio-ventricular node but underwent aggressive rate control to achieve more than 90% of biventricular (BV) complexes. We used 24 hours Holter monitoring because there are data that this method is more accurate than CRT counters. METHODS: We included 30 patients: 21 patients with sinus rhythm and 9 patients with permanent AF with ejection fraction <35%, II-IV NYHA class and wide QRS (>120 ms). We examined patients before implantation of CRT and after 6 months. RESULTS: mean NYHA class decreased from III to II. Distance at 6-min walk test increased by 107 m in AF group and by 105 in sinus rhythm group. EF increased by 7% in AF group and by 6% in sinus rhythm group. Mean time of further observation was 2 years (from 10 months to 5 years). There was 1 death (11.1%) in AF group and 3 deaths (15%) in sinus rhythm group (p>0,05). CONCLUSION: CRT is effective in CHF patients with permanent AF and pharmacological rate control if percent of BV pacing is more than 90% on Holter monitoring.
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Fibrilación Atrial/terapia , Terapia de Resincronización Cardíaca/métodos , Anciano , Fibrilación Atrial/fisiopatología , Electrocardiografía , Femenino , Estudios de Seguimiento , Frecuencia Cardíaca , Humanos , Masculino , Persona de Mediana Edad , Resultado del TratamientoRESUMEN
Takotsubo cardiomyopathy is an acute cardiac syndrome that mimics ST segment elevation myocardial infarction. It is characterized by transient local contractility disturbances as akinesis of the apical and middle segments of the left ventricle concurrent with hyperkinesis of its basal portions in the absence of significant coronary artery changes. A description of 2 clinical cases and a review of literature on this rare myocardial disease are given.
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Cardiomiopatía de Takotsubo/diagnóstico , Anciano , Diagnóstico Diferencial , Ecocardiografía , Electrocardiografía , Femenino , Humanos , Infarto del Miocardio/diagnóstico , Infarto del Miocardio/tratamiento farmacológico , Cardiomiopatía de Takotsubo/tratamiento farmacológico , Tomografía Computarizada por Rayos X , Resultado del TratamientoRESUMEN
AIM: To study structural and functional changes in left ventricular myocardium (LVM) of patients with mild and moderate arterial hypertension (AH) with application of tissue myocardial dopplerechocardiography (TMD), correlation between these changes and parameters of electrophysiological remodeling and circadian profile of blood pressure. MATERIAL AND METHODS: Forty-give hypertensive patients were divided into two groups: the study group 2A consisted of 28 patients with mild AH (144.2 +/- 5.8/89.4 +/- 6.6 mm Hg), group 2B - of 17 patients with moderate AH (160.5 +/- 9.1/101.3 +/- 10.2 mm Hg). The control group consisted of 10 normotensive subjects. All the patients were examined using standard echocardiography with assessment of transmitral blood flow, tissue doppler investigation, circadian monitoring of blood pressure, electro-, vector- and decartocardiography. RESULTS: No significant differences in standard doppler, electro- and vectorcardiographic parameters between the patients with mild and moderate hypertension were found. LVM mass index and LV wall relative thickness significantly increased both in 2A and 2B groups vs controls (p < 0.05). Most patients of group 2A and 50% patients of group 2B had no alterations in LV geometry. Lower blood pressure was associated with LV concentric remodeling, higher - with concentric and excentric hypertrophy. In the presence of LV remodeling hypertensive patients developed more pronounced disorders of diastolic function according to TMD compared to hypertensive patients with normal LV geometry (p < 0.05). TMD detected LV diastolic disorders in 82% patients of group 2A and in 94% - of group 2B, while transmitral doppler study detected diastolic dysfunction only in 14 and 29% patients, respectively. A significant difference by Em/Am was registered between patients with mild and moderate AH only in the area of the mitral ring at the side of LV posterior wall (p < 0.05). CONCLUSION: TMD is able to detect earleast structural-functional myocardial changes in hypertensive patients and to determine significant differences in LV diastolic disorders in patients with mild and moderate AH. No significant differences in LVM mass, standard doppler, electro- and vector-cardiographic parameters were found between AH patients' groups.
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Presión Sanguínea/fisiología , Ecocardiografía Doppler/métodos , Ventrículos Cardíacos/diagnóstico por imagen , Hipertensión/fisiopatología , Función Ventricular Izquierda/fisiología , Remodelación Ventricular/fisiología , Adolescente , Adulto , Anciano , Ritmo Circadiano/fisiología , Electrocardiografía , Femenino , Ventrículos Cardíacos/fisiopatología , Humanos , Hipertensión/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Índice de Severidad de la Enfermedad , Factores de TiempoRESUMEN
AIM: To assess QT/RR relationship in healthy subjects and in patients with acute myocardial infarction (AMI) using long term 12-lead ECG monitoring. MATERIAL AND METHODS: We studied separately diurnal and nocturnal QT interval rate-dependence using a linear model "QT=beta+alphaxRR" in 42 patients with AMI on 2-nd week of the disease and in 14 healthy volunteers. All necessary parameters were automatically calculated from 24-hour 12 lead ECG recordings using special programs. Myocardial perfusion and infarct size were assessed using 99mTc-MIBI gated SPECT. RESULTS: Long-term ECG monitoring permitted: 1) to detect the ECG lead with most pronounced QT/RR relationship delineated by alpha(max); 2) to determine value of "deltaalpha=alpha(max)-alpha(min)", that characterized spatial heterogeneity of QT/RR relationship. In norm diurnal values of alpha(max) were significantly higher than nocturnal ones (0.207+/-0.037 vs. 0.151+/-0.035, respectively; p<0.01). The alpha(max) values correlated with the size of MI (r=0.42-0.43, p<0.01). Therefore in patients with anterior AMI who demonstrated significantly larger defects of 99mTc-MIBI uptake than patients with inferior AMI, diurnal mean value of amax remained high despite therapy with b-blockers (0.225+/-0.037), and nocturnal alpha(max) value significantly exceeded respective amax value in healthy subjects (0.216+/-0.097 vs 0.151+/-0.035, respectively; p<0.01). Patients with AMI demonstrated an increased mean Da value when compared to normal subjects (in anterior AMI 0.098+/-0.057 vs. 0.039+/-0.014, respectively; p<0.001--diurnal period; 0.104+/-0,042 vs. 0.039+/-0.022, respectively; p<0.001--nocturnal period). In anterior AMI Da values correlated with infarct size (r=0.62, p=0.001). CONCLUSIONS: A new approach to the assessment of QT rate dependence with the use of 12-lead Holter monitoring widens possibilities of the method, firstly, because of selection of most informative ECG lead that shows maximal QT/RR relationship dynamic, and, secondly due, to discovery of the new field of ventricular repolarization research by assessment of space dispersion of QT/RR relationship. In patients with AMI when compared with healthy subjects we observed a decrease of QT/RR circadian modulation, increase of the slope and space dispersion of QT/RR rate dependence.
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Electrocardiografía Ambulatoria , Frecuencia Cardíaca/fisiología , Infarto del Miocardio/fisiopatología , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Pronóstico , Índice de Severidad de la EnfermedadRESUMEN
AIM: To assess the state of sympathetic innervation of the heart in patients with acute coronary syndrome. MATERIAL: Patients with Q-myocardial infarction (MI, n=36), non-Q-MI (n=13), and unstable angina (UA, n=9). METHODS: Each subject underwent single-photon emission computed tomography (SPECT) and planar scintigraphy using iodine-123 metaiodobenzylguanidine ((123)I-MIBG) for assessment of cardiac sympathetic function. We analyzed early (15 minutes) and delayed (4 hours) images after (123)I-MIBG administration. Resting (99m)Tc-MIBI myocardial scintigraphy was performed for evaluation of myocardial perfusion. Location, extent (%) and severity (Un.) of defects were determined using <
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Angina Inestable , Sistema Nervioso Simpático , 3-Yodobencilguanidina , Corazón , Humanos , Infarto del Miocardio , Tecnecio Tc 99m SestamibiRESUMEN
The purpose of the investigation was to analyze the data of 64-multislice spiral computed tomography (MSCT-64) versus those of low-dose dobutamine echocardiography (stress EchoCG) used to diagnose the viable myocardium in patients with acute myocardial infarction (AMI). The investigation enrolled 49 patients with AIM. Contrast-enhanced MSCT-64 and low-dose dubutamine stress EchoCG were performed in patients in the early periods of AMI. The viable myocardium was examined in 780 segments of the left ventricle (LV). The data of delayed MSCT and stress EchoCG agreed in 759 (97.3%) segments, did not in 21 (2.7%) segments; Cohen's kappa coefficient was 0.88. The affected segment index (As index) was introduced into the investigation, which is an integral indicator of the number of segments with perfusion defect and nonviable segments detected by MSCT. There was a statistically significant correlation of the As index with the asynergy index (r = 0.91; p = 0.000) and LV ejection fraction (r = -0.75; p = 0.000). Our previous study has demonstrated that MSCT-64 is an informative method to evaluate myocardial viability; the signs of myocardial perfusion and structural derangements can serve as predictors of diminished LV contractility.