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1.
BMC Health Serv Res ; 22(1): 1146, 2022 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-36088408

RESUMEN

BACKGROUND: Worldwide healthcare systems face challenges in assessing and monitoring chronic care pathways and, even more, the value generated for patients. Patient-reported outcomes measures (PROMs) represent a valid Real-World Evidence (RWE) source to fully assess health systems' performance in managing chronic care pathways. METHODS: The originality of the study consists in the chance of adopting PROMs, as a longitudinal assessment tool for continuous monitoring of patients' adherence to therapies and self-care behavior recommendations in clinical practice and as a chance to provide policy makers insights to improve chronic pathways adopting a patient perspective. The focus was on PROMs of patients with chronic heart failure (CHF) collected in the Gabriele Monasterio Tuscan Foundation (FTGM), a tertiary referral CHF centre in Pisa, Italy. During the hospital stay, CHF patients were enrolled and received a link (via SMS or email) to access to the first questionnaire. Follow-up questionnaires were sent 1, 7 and 12 months after the index hospitalisation. Professionals invited 200 patients to participate to PROMs surveys. 174 answers were digitally collected at baseline from 2018 to 2020 and analysed. Quantitative and qualitative analyses were conducted, using Chi2, t-tests and regression models together with narrative evidence from free text responses. RESULTS: Both quantitative and qualitative results showed FTGM patients declared to strongly adhere to the pharmacological therapy across the entire pathway, while seemed less careful to adhere to self-care behavior recommendations (e.g., physical activity). CHF patients that performed adequate Self-Care Maintenance registered outcome improvements. Respondents declared to be supported by family members in managing their adherence. CONCLUSIONS: The features of such PROMs collection model are relevant for researchers, policymakers and for managers to implement interventions aimed at improving pathway adherence dimensions. Among those, behavioral economics interventions could be implemented to increase physical activity among CHF patients since proven successful in Tuscany. Strategies to increase territorial care and support patients' caregivers in their daily support to patients' adherence should be further explored. Systematic PROMs collection would allow to monitor changes in the whole pathway organization. This study brings opportunities for extending such monitoring systems to other organizations to allow for reliable benchmarking opportunities.


Asunto(s)
Insuficiencia Cardíaca , Autocuidado , Enfermedad Crónica , Vías Clínicas , Insuficiencia Cardíaca/terapia , Humanos , Cooperación del Paciente
2.
Eur J Nutr ; 59(7): 2953-2968, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31707544

RESUMEN

PURPOSE: A regular intake of red grape juice has cardioprotective properties, but its role on the modulation of natriuretic peptides (NPs), in particular of C-type NP (CNP), has not yet been proven. The aims were to evaluate: (1) in vivo the effects of long-term intake of Tuscany Sangiovese grape juice (SGJ) on the NPs system in a mouse model of myocardial infarction (MI); (2) in vitro the response to SGJ small RNAs of murine MCEC-1 under physiological and ischemic condition; (3) the activation of CNP/NPR-B/NPR-C in healthy human subjects after 7 days' SGJ regular intake. METHODS: (1) C57BL/6J male and female mice (n = 33) were randomly subdivided into: SHAM (n = 7), MI (n = 15) and MI fed for 4 weeks with a normal chow supplemented with Tuscany SGJ (25% vol/vol, 200 µl/per day) (MI + SGJ, n = 11). Echocardiography and histological analyses were performed. Myocardial NPs transcriptional profile was investigated by Real-Time PCR. (2) MCEC-1 were treated for 24 h with a pool of SGJ small RNAs and cell viability under 24 h exposure to H2O2 was evaluated by MTT assay. (3) Human blood samples were collected from seven subjects before and after the 7 days' intake of Tuscany SGJ. NPs and miRNA transcriptional profile were investigated by Real-Time PCR in MCEC-1 and human blood. RESULTS: Our experimental data, obtained in a multimodal pipeline, suggest that the long-term intake of SGJ promotes an adaptive response of the myocardium to the ischemic microenvironment through the modulation of the cardiac CNP/NPR-B/NPR-C system. CONCLUSIONS: Our results open new avenue in the development of functional foods aimed at enhancing cardioprotection of infarcted hearts through action on the myocardial epigenome.


Asunto(s)
Péptido Natriurético Tipo-C , Vitis , Animales , Femenino , Expresión Génica , Peróxido de Hidrógeno , Masculino , Ratones , Ratones Endogámicos C57BL , Péptido Natriurético Tipo-C/genética , Péptidos Natriuréticos/genética
3.
J Intern Med ; 277(5): 605-14, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25346163

RESUMEN

BACKGROUND: Cardiac involvement in systemic amyloidosis is caused by the extracellular deposition of misfolded proteins, mainly immunoglobulin light chains (AL) or transthyretin (ATTR), and may be detected by cardiovascular magnetic resonance (CMR). The aim of this study was to measure myocardial extracellular volume (ECV) in amyloid patients with a novel T1 mapping CMR technique and to determine the correlation between ECV and disease severity. METHODS: Thirty-six patients with biopsy-proven systemic amyloidosis (mean age 70 ± 9 years, 31 men, 30 with AL and six with ATTR amyloidosis) and seven patients with possible amyloidosis (mean age 64 ± 10 years, six men) underwent comprehensive clinical and CMR assessment, with ECV estimation from pre- and postcontrast T1 mapping. Thirty healthy subjects (mean age 39 ± 17 years, 21 men) served as the control group. RESULTS: Amyloid patients presented with left ventricular (LV) concentric hypertrophy with impaired biventricular systolic function. Cardiac ECV was higher in amyloid patients (definite amyloidosis, 0.43 ± 0.12; possible amyloidosis, 0.34 ± 0.11) than in control subjects (0.26 ± 0.04, P < 0.05); even in amyloid patients without late gadolinium enhancement (0.35 ± 0.10), ECV was significantly higher than in the control group (P < 0.01). A cut-off value of myocardial ECV >0.316, corresponding to the 95th percentile in normal subjects, showed a sensitivity of 79% and specificity of 97% for discriminating amyloid patients from control subjects (area under the curve of 0.884). Myocardial ECV was significantly correlated with LV ejection fraction (R(2)  = 0.16), LV mean wall thickness (R(2)  = 0.41), LV diastolic function (R(2)  = 0.21), right ventricular ejection fraction (R(2)  = 0.13), N-terminal fragment of the pro-brain natriuretic peptides (R(2)  = 0.23) and cardiac troponin (R(2)  = 0.33). CONCLUSION: Myocardial ECV was increased in amyloid patients and correlated with disease severity. Thus, measurement of myocardial ECV represents a potential noninvasive index of amyloid burden for use in early diagnosis and disease monitoring.


Asunto(s)
Amiloide/metabolismo , Amiloidosis/metabolismo , Cardiomiopatías/metabolismo , Miocardio/metabolismo , Anciano , Estudios de Casos y Controles , Medios de Contraste , Femenino , Gadolinio , Humanos , Angiografía por Resonancia Magnética , Imagen por Resonancia Cinemagnética , Masculino , Persona de Mediana Edad , Estudios Prospectivos
4.
Int J Cardiol ; 283: 107-111, 2019 05 15.
Artículo en Inglés | MEDLINE | ID: mdl-30819586

RESUMEN

BACKGROUND: While left atrial (LA) size has been shown as a strong predictor of cardiovascular diseases in various studies, the role of right atrial (RA) enlargement, especially in the growing population of patients with congenital heart diseases (CHD) is largely unknown. We sought to evaluate (1) RA and LA volumes in patients with repaired Tetralogy of Fallot (TOF) and assess correlations to (2) functional parameters and (3) clinical adverse events. METHODS: 169 patients with repaired TOF were enrolled following a targeted protocol for Cardiovascular magnetic resonance imaging (CMR), Cardiopulmonary exercise tests (CPET), Echocardiography and Measurement of NT-proBNP. Clinical history was assessed at enrollment and during a median Follow-up of 23 months (IQR 9-40). The primary clinical endpoint was a composite of all cause mortality, aborted sudden cardiac death and sustained VT. Prespecified secondary surrogate endpoint included worsening heart failure (NYHA III-IV), non-sustained VT and sustained supraventricular tachycardia. RESULTS: RA Systolic indexed volume (RASVi) correlated with LA Systolic indexed volume (LASVi) (r = 0.59, p < 0.001) and both correlated with the patient age (r = 0.52, p < 0.001; r = 0.59, p < 0.001 respectively). Patients in the upper tertil of RASVi (>58 ml/m2) had higher NT-proBNP levels, longer QRS duration, larger ventricle diameters, higher RV mass and lower peak oxygen uptake. RASVi was associated with the primary composite adverse event at univariate Cox-regression analysis (HR: 1.044, CI: 1.008-1.08, p = 0.01). Bayesian Multivariate model averaging revealed RASVi as predictor of secondary surrogate adverse outcome (HR: 1.06, CI: 1.053-1.068, Pb = 0,889). CONCLUSION: Among patients with repaired TOF, RA dilatation is an independent predictor for adverse clinical events. As such, routine assessment of RA volumes could be useful to further improve decision-making and management of these patients in the future.


Asunto(s)
Procedimientos Quirúrgicos Cardíacos/métodos , Atrios Cardíacos/diagnóstico por imagen , Tetralogía de Fallot/cirugía , Adolescente , Adulto , Anciano , Volumen Cardíaco , Causas de Muerte/tendencias , Niño , Progresión de la Enfermedad , Ecocardiografía , Prueba de Esfuerzo , Femenino , Estudios de Seguimiento , Atrios Cardíacos/fisiopatología , Humanos , Italia/epidemiología , Imagen por Resonancia Cinemagnética , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Tasa de Supervivencia/tendencias , Tetralogía de Fallot/diagnóstico , Tetralogía de Fallot/mortalidad , Adulto Joven
5.
G Ital Nefrol ; 23 Suppl 34: S32-7, 2006.
Artículo en Italiano | MEDLINE | ID: mdl-16633992

RESUMEN

The recent discovery of cardiac endocrine function, together with the development of accurate and feasible assay methods for cardiac natriuretic hormone evaluation, i.e. for B-type natriuretic peptide (BNP) and inactive peptide NT-proBNP have confirmed their pathophysiological and clinical significance for cardiovascular disease assessment. Concerning heart failure, their value is for diagnostic screening in selected/unselected populations, for differential diagnosis of dyspnea and for prognostic stratification, and as a guide for follow-up and treatment of patients. Recent Italian recommendations pointed out that BNP/NT-proBNP has a role in ruling-out the diagnosis of heart failure in patients with dubious signs/symptoms: plasma BNP/NT-proBNP concentrations help in the clinical evaluation of chronic heart failure patients when risk stratification is needed, whereas the routine BNP/NT-proBNP assay is still not recommended to guide therapeutic decision-making.


Asunto(s)
Insuficiencia Cardíaca/diagnóstico , Péptidos Natriuréticos/sangre , Insuficiencia Cardíaca/sangre , Humanos , Péptidos Natriuréticos/fisiología
6.
J Am Coll Cardiol ; 35(6): 1462-9, 2000 May.
Artículo en Inglés | MEDLINE | ID: mdl-10807448

RESUMEN

OBJECTIVES: To assess whether talking or reading (silently or aloud) could affect heart rate variability (HRV) and to what extent these changes require a simultaneous recording of respiratory activity to be correctly interpreted. BACKGROUND: Sympathetic predominance in the power spectrum obtained from short- and long-term HRV recordings predicts a poor prognosis in a number of cardiac diseases. Heart rate variability is often recorded without measuring respiration; slow breaths might artefactually increase low frequency power in RR interval (RR) and falsely mimic sympathetic activation. METHODS: In 12 healthy volunteers we evaluated the effect of free talking and reading, silently and aloud, on respiration, RR and blood pressure (BP). We also compared spontaneous breathing to controlled breathing and mental arithmetic, silent or aloud. The power in the so called low- (LF) and high-frequency (HF) bands in RR and BP was obtained from autoregressive power spectrum analysis. RESULTS: Compared with spontaneous breathing, reading silently increased the speed of breathing (p < 0.05), decreased mean RR and RR variability and increased BP. Reading aloud, free talking and mental arithmetic aloud shifted the respiratory frequency into the LF band, thus increasing LF% and decreasing HF% to a similar degree in both RR and respiration, with decrease in mean RR but with minor differences in crude RR variability. CONCLUSIONS: Simple mental and verbal activities markedly affect HRV through changes in respiratory frequency. This possibility should be taken into account when analyzing HRV without simultaneous acquisition and analysis of respiration.


Asunto(s)
Nivel de Alerta/fisiología , Frecuencia Cardíaca/fisiología , Solución de Problemas/fisiología , Ventilación Pulmonar/fisiología , Lectura , Conducta Verbal/fisiología , Artefactos , Presión Sanguínea/fisiología , Electrocardiografía , Humanos , Masculino , Valores de Referencia , Procesamiento de Señales Asistido por Computador , Sistema Nervioso Simpático/fisiología
7.
Cardiovasc Res ; 34(2): 273-80, 1997 May.
Artículo en Inglés | MEDLINE | ID: mdl-9205540

RESUMEN

OBJECTIVE: To test the hypothesis that prolonged physical exercise induces long-lasting effects on blood pressure and heart rate we studied 17 endurance runners before and after the 1995 Sandia Wilderness Crossing Research Run (46 km of rocky trails, average altitude 2500 m). METHODS: We evaluated the response of the cardiovascular system to sympathetic stimulation by orthostatism and to sympathetic and parasympathetic carotid baroreceptor stimulations by sinusoidal neck suction at different frequencies (sympathetic activity on blood pressure by low-frequency stimulation, parasympathetic activity on RR interval by high-frequency stimulation). We used power spectral analysis of beat-to-beat RR interval, systolic and diastolic non-invasive blood pressure, in order to quantify the respiratory fluctuations (depending on vagal activity on the RR interval) and the slower non-respiratory fluctuations, depending on sympathetic activity on the blood pressure. Recordings were performed 24 h before, and 30 min, 24 h and 48 h after the run. RESULTS: Thirty minutes after the race we found reduced blood pressure, signs of relative sympathetic predominance (increased RR interval low-frequency/high-frequency ratio from 0.65 +/- 0.15 to 1.63 +/- 0.37, P < 0.05), reduced effect of parasympathetic baroreceptor stimulation (decrease in RR interval high-frequency neck-suction synchronous oscillations, from 5.33 +/- 0.34 to 3.55 +/- 0.37 ln-ms2, P < 0.005), unchanged blood pressure responses to sympathetic stimulations; 24 h after the race, the response to parasympathetic stimulation was increased (to 6.44 +/- 0.32 ln-ms2, P < 0.0005) compared to baseline (24 h before the race), whereas sympathetic stimulation by neck suction had no longer an effect on blood pressure. CONCLUSION: The acute effects of prolonged exertion are associated with a relative increase in sympathetic activity. Twenty-four hours after this race an increased sensitivity to vagal and reduced sensitivity to sympathetic baroreflex stimulation was found. In this field study at altitude we found long-lasting effects on cardiovascular autonomic modulation after physical exertion.


Asunto(s)
Altitud , Sistema Nervioso Autónomo/fisiología , Barorreflejo/fisiología , Corazón/fisiología , Resistencia Física/fisiología , Carrera/fisiología , Adulto , Anciano , Presión Sanguínea/fisiología , Electrocardiografía , Femenino , Frecuencia Cardíaca/fisiología , Humanos , Masculino , Persona de Mediana Edad , Cuello , Postura , Procesamiento de Señales Asistido por Computador , Succión , Factores de Tiempo
8.
Hypertension ; 26(1): 20-5, 1995 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-7607725

RESUMEN

This study assesses (1) the relation of the very-low-frequency vasomotion (< 0.02 Hz) of the radial artery of young healthy volunteers to regional blood flow and (2) its distribution in the upper extremities. Radial artery diameters from comparable sites were measured on contralateral extremities in 18 young healthy volunteers by an echo tracking system simultaneously with blood flow velocity determined by continuous wave Doppler and blood pressure acquired by photoplethysmography in the middle finger. A synchronous global pattern of vasomotion was detected on contralateral radial arteries, suggesting the presence of either a centrally located pacemaker or a humoral system. Modulation of sympathovagal balance in 8 subjects did not significantly alter either the frequency or amplitude of the very-low-frequency vasomotor waves. Matching patterns of diameter and flow oscillations of the very-low-frequency type recorded at the same site were obtained in 10 strictly nonsmoking volunteers for given periods of time. A consistent phase lag was observed between flow and diameter signals. Flow always preceded the diameter fluctuations by a mean (+/- SEM) course of 20.8 +/- 1.56 seconds. Although the physiological basis for oscillatory behavior remains for the moment highly speculative, these results suggest that the very-low-frequency vasomotion pattern in this conduit vessel might be a flow- or shear stress-dependent phenomenon. Shear stress changes at the endothelium modulate vascular tone through the release of vasodilators. The noninvasive assessment of the diameter-flow relation may thus offer a new way of addressing vascular wall function in medium-sized and large arteries in subjects with cardiovascular risk factors.


Asunto(s)
Arterias/diagnóstico por imagen , Arterias/fisiología , Flujo Sanguíneo Regional , Sistema Vasomotor/fisiología , Adulto , Brazo/irrigación sanguínea , Fenómenos Biomecánicos , Presión Sanguínea , Femenino , Hemodinámica , Humanos , Flujometría por Láser-Doppler , Masculino , Modelos Biológicos , Oscilometría , Fotopletismografía , Arteria Radial/diagnóstico por imagen , Arteria Radial/fisiología , Ultrasonografía
9.
J Hypertens ; 19(2): 213-22, 2001 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-11212963

RESUMEN

OBJECTIVES: Regulation of the vascular system may limit physical performance and contribute to adaptation to high altitude. We evaluated vascular function in 10 Himalayan high-altitude natives and 10 recently acclimatized sea-level natives at an altitude of 5,050 m. METHODS: We registered electrocardiogram, blood flow velocity in the common femoral artery, and blood pressure in the radial artery using non-invasive methods under baseline conditions, and during maximal vasodilation after 2 min leg occlusion. Vascular mechanics were characterized by estimating pulse wave velocity and input impedance. RESULTS: Pulse wave velocity and parameters of input impedance did not differ between groups under baseline conditions. In the post-ischemic period, the ratio between maximal hyperemic and baseline blood flow velocity was significantly higher in the high-altitude than in the sea-level natives (5.7 +/- 2.5 versus 3.8 +/- 1.2, P < 0.05). The leg vascular resistance decreased in the post-occlusive period without differences between groups. Characteristic impedance decreased in the post-ischemic period by about one third of the baseline level without differences between groups. The post-ischemic decrease of input impedance modulus was more marked in the high-altitude than in the sea-level natives at low frequencies (28 +/- 12 versus 6.4 +/- 20% at 2 Hz, P < 0.01). CONCLUSIONS: Our results demonstrate a superior ability to increase blood flow velocity as a response to muscular ischemia in high-altitude natives compared to sea-level natives. This phenomenon may be associated with a more effective coupling between blood pressure and blood flow which is probably caused by differences in conduit vessel function.


Asunto(s)
Altitud , Arterias/fisiología , Hipoxia/fisiopatología , Adolescente , Adulto , Velocidad del Flujo Sanguíneo , Presión Sanguínea , Impedancia Eléctrica , Electrocardiografía , Femenino , Frecuencia Cardíaca , Humanos , Masculino , Persona de Mediana Edad
10.
J Hypertens ; 19(5): 947-58, 2001 May.
Artículo en Inglés | MEDLINE | ID: mdl-11393679

RESUMEN

OBJECTIVE: To assess the influence of different breathing patterns on autonomic cardiovascular modulation during acute exposure to altitude-induced hypoxia. DESIGN: We measured relative changes in minute ventilation (VE), oxygen saturation (%SaO2), spectral analysis of RR interval and blood pressure, and response to stimulation of carotid baroreceptors (neck suction) at baseline and after acute (1 h) hypobaric hypoxia (equivalent to 5,000 m, in a hypobaric chamber). METHODS: We studied 19 human subjects: nine controls and 10 Western yoga trainees of similar age, while breathing spontaneously, at 15 breaths/min (controlled breathing) and during 'complete yogic breathing' (slow diaphragmatic + thoracic breathing, approximately 5 breaths/min) in yoga trainees, or simple slow breathing in controls. RESULTS: At baseline %SaO2, VE and autonomic pattern were similar in both groups; simulated altitude increased VE in controls but not in yoga trainees; %SaO2 decreased in all subjects (P< 0.0001), but more in controls than in yoga trainees (17 versus 12%, 14 versus 9%, 14 versus 8%, all P< 0.05 or better, during spontaneous breathing, controlled breathing and yogic or slow breathing, respectively). Simulated altitude decreased RR interval (from 879 +/- 45 to 770 +/- 39, P < 0.01) and increased indices deducted from spectral analysis of heart rate variability (low frequency/high frequency (LF/HF) ratio from 1.6 +/- 0.5 to 3.2 +/- 1.1, P < 0.05) and systolic blood pressure (low-frequency fluctuations from 2.30 +/- 0.31 to 3.07 +/- 0.24 In-mmHg2, P< 0.05) in controls, indicating sympathetic activation; these changes were blunted in yoga trainees, and in both groups during slow or yogic breathing. No effect of altitude was seen on stimulation of carotid baroreceptors in both groups. CONCLUSIONS: Well-performed slow yogic breathing maintains better blood oxygenation without increasing VE (i.e. seems to be a more efficient breathing) and reduces sympathetic activation during altitude-induced hypoxia.


Asunto(s)
Altitud , Sistema Nervioso Autónomo/fisiopatología , Sistema Cardiovascular/inervación , Hipoxia/fisiopatología , Respiración , Adulto , Presión Sanguínea/fisiología , Femenino , Frecuencia Cardíaca/fisiología , Humanos , Masculino , Cuello , Oxígeno/sangre , Presorreceptores/fisiología , Succión , Yoga
11.
J Neurol Sci ; 219(1-2): 101-6, 2004 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-15050445

RESUMEN

Headache is common in Cerro de Pasco (CP), Peru (altitude 4338 m) and was present in all patients with chronic mountain sickness (CMS) in CP reported here. Forty-seven percent of inhabitants report headache. Twenty-four percent of men have migraine with aura, with an average of 65 attacks a year. We assessed vasoreactivity of the cerebral vessels to CO2 by rebreathing and to NO by the administration of isosorbite dinitrate (IDN), a nitric oxide (NO) donor, using transcranial Doppler ultrasound in the middle cerebral artery (MCA) in natives of CP, some of whom suffered from CMS. We repeated the measurements in Lima (altitude 150 m) in the same subjects within 24 h of arrival. Vasodilatation in the middle cerebral artery supply territory in response to CO2 and NO, both physiologic vasodilators, is defective in Andean natives at altitude and in the same subjects at sea level. Incapacitating migraine can occur with impaired cerebral vasoreactivity to physiologic vasodilators. We propose that susceptibility to migraine might depend in part on gene expression with consequent alterations of endothelial function.


Asunto(s)
Mal de Altura/fisiopatología , Altitud , Circulación Cerebrovascular/fisiología , Migraña con Aura/fisiopatología , Mal de Altura/diagnóstico por imagen , Mal de Altura/metabolismo , Dióxido de Carbono/metabolismo , Enfermedad Crónica , Humanos , Masculino , Arteria Cerebral Media/diagnóstico por imagen , Arteria Cerebral Media/fisiología , Migraña con Aura/diagnóstico por imagen , Migraña con Aura/metabolismo , Óxido Nítrico/metabolismo , Perú , Ultrasonografía Doppler Transcraneal
12.
Recenti Prog Med ; 84(6): 443-56, 1993 Jun.
Artículo en Italiano | MEDLINE | ID: mdl-8516554

RESUMEN

The nature of most syncopal episodes, previously unknown, was recently elucidated by new diagnostic techniques such as the use of the tilt test. The vasovagal syncope can be clinically diagnosed by means of the tilt test. The transitory loss of consciousness during prolonged orthostasis is typically associated with sudden hypotension and bradycardia, which are commonly preceded by relative tachycardia and by premonitory symptoms such as pallor, nausea, asthenia, yawns, hyperventilation, mydriasis, humming, lasting several minutes. The nature of the vasovagal reflex is now better understood: in subjects with vasovagal syncope, during prolonged orthostasis, it was observed a fall in the venous return, inducing an increased sympathetic drive to the heart (with positive inotropic and chronotropic effect) and a lower ventricular filling. The powerful contraction around an almost empty cardiac chamber induces the activation of ventricular mechanoreceptors, and through a reflex mechanism, a sudden increase in the vagal and a sudden reduction in the sympathetic drive. These autonomic changes are responsible for a sudden hypotension and bradycardia. The discussion is still open about the origin of the reduced venous return: it probably originates from a redistribution in the blood volume, due to a venous pooling in the lower limbs or from a reduced muscle tone, because many subjects with vasovagal syncope are slender and with less developed muscle apparatus. Others suggest that a reduction in the sympathetic drive to the vessels, responsible for a progressive hypotension in the minutes preceding syncopal episodes, is the origin of the reduced venous return. In this review a diagnostic pattern for the assessment of the vasovagal syncope is suggested. The medical history, clinical examination, electro- and echocardiogram, chest x-ray identify two main groups of patients (with or without cardiopathy) who will follow different diagnostic protocols. The therapy of vasovagal syncope, which is based on beta-blockers, scopolamine, dysopiramide and plasma expanders, is reviewed.


Asunto(s)
Reflejo Anormal/fisiología , Síncope/etiología , Nervio Vago/fisiopatología , Hemodinámica , Humanos , Hipotensión Ortostática/sangre , Hipotensión Ortostática/complicaciones , Hipotensión Ortostática/fisiopatología , Síncope/sangre , Síncope/clasificación , Síncope/diagnóstico , Síncope/fisiopatología
13.
Arch Physiol Biochem ; 119(5): 219-24, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23862573

RESUMEN

CONTEXT: High altitude (HA) is a model of severe hypoxia exposure in humans. We hypothesized that nocturnal hypoxemia or acute maximal exercise at HA might affect plasma leptin and VEGF levels. OBJECTIVES: Plasma leptin, VEGF and other metabolic variables were studied after nocturnal pulse oximetry and after maximal exercise in healthy lowlanders on the 3rd-4th day of stay in Lobuche (5050 m, HA) and after return to sea level (SL). RESULTS: Leptin was similar at SL or HA in both pre- and post-exercise conditions. Pre-exercise VEGF at HA was lower, and cortisol was higher, than at SL, suggesting that nocturnal intermittent hypoxia associated with periodic breathing at HA might affect these variables. CONCLUSIONS: Leptin levels appear unaffected at HA, whereas nocturnal hypoxic stress may affect plasma VEGF. Future HA studies should investigate the possible role of nocturnal intermittent hypoxemia on metabolism.


Asunto(s)
Altitud , Voluntarios Sanos , Leptina/sangre , Factor A de Crecimiento Endotelial Vascular/sangre , Adulto , Ejercicio Físico , Femenino , Humanos , Hipoxia/sangre , Hipoxia/metabolismo , Masculino , Oxihemoglobinas/metabolismo
14.
Eur J Prev Cardiol ; 19(3): 428-35, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21543459

RESUMEN

BACKGROUND: Brain natriuretic peptide (BNP) predicts exercise performance and exercise training may modulate BNP and its N-terminal portion (NT-pro-BNP), we therefore conducted an individual patient analysis of exercise training effects on BNP and NT-pro-BNP. AIMS: To use an individual patient meta-analysis to relate changes in BNP, NT-pro-BNP, and peak VO(2); to link these changes to volume parameters of exercise training programmes (intensity etc.); and to identify patient characteristics likely to lead to greater improvements in BNP, NT-pro-BNP, and peak VO(2). DESIGN: Individual patient meta-analysis. METHODS: A systematic search was conducted of Medline (Ovid), Embase.com, Cochrane Central Register of Controlled Trials, and CINAHL (until July 2008) to identify randomized controlled trials of aerobic and/or resistance exercise training in systolic heart failure patients measuring BNP and/or NT-pro-BNP. Primary outcome measures were change in BNP, NT-pro-BNP, and peak VO2. Subanalyses were conducted to identify (1) patient groups that benefit most and (2) exercise programme parameters enhancing favourable changes in primary outcome measures. RESULTS: Ten randomized controlled studies measuring BNP or NT-pro-BNP met eligibility criteria, authors provided individual patient data for 565 patients (313 exercise and 252 controls). Exercise training had favourable effects on BNP (-28.3%, p < 0.0001), NT-pro-BNP (-37.4%, p = < 0.0001), and peak VO(2) (17.8%, p < 0.0001). The analysis showed a significant change in primary outcome measures; moreover, change in BNP (r = -0.31, p < 0.0001) and NT-pro-BNP (r = -0.22, p < 0.0001) were correlated with peak VO(2) change. CONCLUSION: Exercise training has favourable effects on BNP, NT-pro-BNP, and peak VO(2) in heart failure patients and BNP/NT-pro-BNP changes were correlated with peak VO(2) changes.


Asunto(s)
Terapia por Ejercicio , Insuficiencia Cardíaca/rehabilitación , Péptido Natriurético Encefálico/sangre , Anciano , Análisis de Varianza , Biomarcadores/sangre , Tolerancia al Ejercicio , Femenino , Insuficiencia Cardíaca/sangre , Insuficiencia Cardíaca/fisiopatología , Humanos , Masculino , Persona de Mediana Edad , Consumo de Oxígeno , Fragmentos de Péptidos/sangre , Factores de Tiempo , Resultado del Tratamiento
15.
Respir Physiol Neurobiol ; 177(3): 333-41, 2011 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-21621651

RESUMEN

The relationship between work rate (WR) and its tolerable duration (t(LIM)) has not been investigated at high altitude (HA). At HA (5050 m) and at sea level (SL), six subjects therefore performed symptom-limited cycle-ergometry: an incremental test (IET) and three constant-WR tests (% of IET WR(max), HA and SL respectively: WR(1) 70±8%, 74±7%; WR(2) 86±14%, 88±10%; WR(3) 105±13%, 104±9%). The power asymptote (CP) and curvature constant (W') of the hyperbolic WR-t(LIM) relationship were reduced at HA compared to SL (CP: 81±21 vs. 123±38 W; W': 7.2±2.9 vs. 13.1±4.3 kJ). HA breathing reserve (estimated maximum voluntary ventilation minus end-exercise ventilation) was also compromised (WR(1): 25±25 vs. 50±18 l min(-1); WR(2): 4±23 vs. 38±23 l min(-1); WR(3): -3±18 vs. 32±24 l min(-1)) with near-maximal dyspnea levels (Borg) (WR(1): 7.2±1.2 vs. 4.8±1.3; WR(2): 8.8±0.8 vs. 5.3±1.2; WR(3): 9.3±1.0 vs. 5.3±1.5). The CP reduction is consistent with a reduced O(2) availability; that of W' with reduced muscle-venous O(2) storage, exacerbated by ventilatory limitation and dyspnea.


Asunto(s)
Altitud , Tolerancia al Ejercicio/fisiología , Resistencia Física/fisiología , Ventilación Pulmonar/fisiología , Adulto , Mal de Altura/etiología , Mal de Altura/fisiopatología , Prueba de Esfuerzo , Femenino , Humanos , Masculino , Persona de Mediana Edad
16.
Neuromuscul Disord ; 20(8): 512-6, 2010 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-20580235

RESUMEN

Mutations in the lamin A/C gene (LMNA) are known to be involved in several diseases such as Emery-Dreifuss muscular dystrophy, limb-girdle muscular dystrophy type 1B and dilated cardiomyopathies with conduction disease, with considerable phenotype heterogeneity. Here we report on a novel autosomal dominant mutation in LMNA in two direct relatives presenting with different clinical phenotypes, characterized by severe life-threatening limb-girdle muscle involvement and cardiac dysfunction treated with heart transplantation in the proband, and by ventricular tachyarrhythmias with preserved cardiac and skeletal muscle function in her young son. To our knowledge, this is the first report of a duplication in the LMNA gene. The two phenotypes described could reflect different clinical stages of the same disease. We hypothesize that early recognition and initiation of therapeutic manoeuvres in the younger patient may retard the rate of progression of the cardiomyopathy.


Asunto(s)
Cardiopatías/genética , Cardiopatías/fisiopatología , Trasplante de Corazón/fisiología , Corazón/fisiopatología , Lamina Tipo A/genética , Distrofia Muscular de Cinturas/genética , Adulto , Secuencia de Aminoácidos , Cardiomiopatía Dilatada/diagnóstico por imagen , Cardiomiopatía Dilatada/genética , Cardiomiopatía Dilatada/patología , Electrocardiografía , Femenino , Duplicación de Gen , Cardiopatías/diagnóstico por imagen , Humanos , Inmunohistoquímica , Proteínas de la Membrana/genética , Persona de Mediana Edad , Datos de Secuencia Molecular , Debilidad Muscular/genética , Músculo Esquelético/patología , Distrofia Muscular de Cinturas/diagnóstico por imagen , Distrofia Muscular de Cinturas/patología , Proteínas Nucleares/genética , Linaje , Fenotipo , Volumen Sistólico/fisiología , Tomografía Computarizada por Rayos X
18.
Pediatr Cardiol ; 28(5): 339-45, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17607499

RESUMEN

To evaluate the relationship between plasma concentration of amino-terminal fragment of pro-brain natriuretic peptide (NT-proBNP), functional capacity, and right ventricular overload in survivors of tetralogy of Fallot (TOF) repair, we prospectively studied 70 operated TOF patients (44 males, 21 +/- 1 years old; mean +/- SEM) who underwent, during the same day, echocardiography, cardiac magnetic resonance imaging, neurohormonal characterization (plasma NT-proBNP, catecholamines, plasma renin activity, and aldosterone assay), and cardiopulmonary exercise testing. Forty-eight age- and sex-matched healthy volunteers served as the control group. Compared to controls, maximal workload and peak oxygen consumption (VO2/kg) were lower in operated TOF patients (p < 0.001), whereas NT-proBNP concentration was elevated (p < 0.001). No difference was found among the other neurohormones. In operated TOF patients, NT-proBNP showed a significant positive correlation with right ventricular (RV) end systolic and end diastolic volumes and RV systolic pressure, and it showed a negative correlation with peak VO2/kg and RV ejection fraction. From multivariable analysis, NT-proBNP concentration was found to be an independent predictor of peak VO2/kg, RV end systolic volume, and RV systolic pressure. These results show an association among RV overload, decrease in functional capacity, and cardiac natriuretic peptide expression in operated TOF patients. NT-proBNP plasma assay may be a useful tool for diagnostic purposes and for decision making in this setting.


Asunto(s)
Péptido Natriurético Encefálico/sangre , Fragmentos de Péptidos/sangre , Tetralogía de Fallot/fisiopatología , Disfunción Ventricular Derecha/diagnóstico , Adolescente , Adulto , Área Bajo la Curva , Niño , Preescolar , Estudios Transversales , Ecocardiografía Doppler , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Análisis Multivariante , Estudios Prospectivos , Curva ROC , Tetralogía de Fallot/cirugía , Disfunción Ventricular Derecha/diagnóstico por imagen
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