Evaluation of the Electroglottographic Signal Variability in Organic and Functional Dysphonia.

OBJECTIVES: To confirm the data reported in our previous studies on the analysis of the variability of the electroglottographic signal in the pathological voice; to evaluate possible differences in variability between organic and functional pathologies; to identify any distinctive/typical EGG patterns for these pathologies. METHODS: One hundred twenty-five subjects were enrolled (36 euphonic and 89 pathological: 24 functional dysphonia, 21 bilateral vocal nodules, 23 unilateral polyps and 21 unilateral cysts). All subjects were studied with videolaryngostroboscopy, spectrographic analysis of voice and electroglottography (EGG). The EGG signal variability was then investigated using amplitude-speed combined analysis, by means of a proprietary software algorithm. Amplitude and Speed variation were expressed as a new parameter, the Variability Index (VI), calculated both for the whole EGG signal recorded (VI-tot) and in each phase of the glottic cycle (VI-Q, absolute value; VI-Q%, percentage value). RESULTS: In the comparison of VI values between pathological and normal groups, VI-tot and VI-Q2% (which corresponds to the final phase of vocal fold contact) were significantly greater in pathological subjects (P= 0.002). The comparison of VI values among subgroups of the various pathologies showed a difference for VI-tot (P< 0.0001) and VI-Q2% (P= 0.001); this difference was more marked in the cysts than in the functional dysphonia. The cut-off values of VI-tot and VI-Q2% were 0.191 and 18.17%, respectively (sensitivity and specificity 65.2% and 66.7% for VI-tot and 84.3% and 77.8% for VI-Q2%). CONCLUSIONS: The variability of the EGG signal investigated through the combined analysis of the amplitude and the speed of vibration using a proprietary algorithm software has proved useful not only to distinguish the normal voice from the pathological voice, but also to characterize which phases are more altered in the various voice pathologies studied, both functional and organic. Furthermore, the analysis of the VI parameter allowed to propose cut-off values characterized by a good sensitivity and specificity to discriminate dysphonia from the euphonic voice. Larger groups of patients will be needed to confirm these results.

A new method for QRS complex detection in multichannel ECG: Application to self-monitoring of fetal health.

This paper proposes a new approach for QRS complex detection in multichannel ECG and presents its application to fetal QRS (fQRS) detection in signals acquired from maternal abdominal leads. The method exploits the characteristics of pseudo-periodicity and time shape of QRS, it consists of devising a quality index (QI) which synthesizes these characteristics and of finding the linear combination of the acquired ECGs, which maximizes this QI. In the application for fQRS detection two QIs are devised, one QI (mQI) for maternal ECG (mECG) and one QI (fQI) for fetal ECG (fECG). The method is completely unsupervised and based on the following steps: signal pre-processing; maternal QRS-enhanced signal extraction by finding the linear combination that maximize the mQI; detection of maternal QRSs; mECG component approximation and canceling by weighted Singular Value Decomposition (SVD); fQRS-enhanced signal extraction by finding the linear combination that maximize the fQI and fQRS detection. The proposed method was compared with our previously developed Independent Component Analysis (ICA) based method as well as with simple mECG canceling and simple ICA methods. The comparison was carried out by evaluating the performances of the procedures in fQRS detection. The new method outperformed the results of the other approaches on the annotated open set of the Computing in Cardiology Challenge 2013 database. The proposed method seems to be promising for its implementation on portable device and for use in self-monitoring of fetal health in pregnant women.

Electronic medical record in cardiology: a 10-year Italian experience.

OBJECTIVES: the aim of this study was to report a ten years experience in the electronic medical record (EMR) use. An estimated 80% of healthcare transactions are still paper-based. METHODS: an EMR system was built at the end of 1998 in an Italian tertiary care center to achieve total integration among different human and instrumental sources, eliminating paper-based medical records. Physicians and nurses who used EMR system reported their opinions. In particular the hospital activity supported electronically, regarding 4,911 adult patients hospitalized in the 2004- 2008 period, was examined. RESULTS: the final EMR product integrated multimedia document (text, images, signals). EMR presented for the most part advantages and was well adopted by the personnel. Appropriateness evaluation was also possible for some procedures. Some disadvantages were encountered, such as start-up costs, long time required to learn how to use the tool, little to no standardization between systems and the EMR technology. CONCLUSION: the EMR is a strategic goal for clinical system integration to allow a better health care quality. The advantages of the EMR overcome the disadvantages, yielding a positive return on investment to health care organization.

Electronic medical record in cardiology: a 10-year Italian experience / Registros médicos eletrônicos em cardiologia: uma experiência italiana em 10 anos

SummaryObjectives:the aim of this study was to report a ten years experience in the electronic medical record (EMR) use. An estimated 80% of healthcare transactions are still paper-based.Methods:an EMR system was built at the end of 1998 in an Italian tertiary care center to achieve total integration among different human and instrumental sources, eliminating paper-based medical records. Physicians and nurses who used EMR system reported their opinions. In particular the hospital activity supported electronically, regarding 4,911 adult patients hospitalized in the 2004- 2008 period, was examined.Results:the final EMR product integrated multimedia document (text, images, signals). EMR presented for the most part advantages and was well adopted by the personnel. Appropriateness evaluation was also possible for some procedures. Some disadvantages were encountered, such as start-up costs, long time required to learn how to use the tool, little to no standardization between systems and the EMR technology.Conclusion:the EMR is a strategic goal for clinical system integration to allow a better health care quality. The advantages of the EMR overcome the disadvantages, yielding a positive return on investment to health care organization.

ResumoObjetivos:o objetivo deste estudo foi relatar uma experiência de 10 anos de utilização de registro médico eletrônico (EMR). Estima-se que 80% das transações na saúde ainda são feitas em papel.Métodos:um sistema de EMR foi implementado ao final de 1998, em um centro italiano de cuidados terciários, com o objetivo de alcançar uma total integração entre diferentes recursos humanos e instrumentais, eliminando registros médicos em papel. Médicos e enfermeiros que utilizaram o sistema EMR relataram suas opiniões. Foi analisada a atividade hospitalar amparada eletronicamente relacionada a 4.911 pacientes adultos hospitalizados, no período de 2004 a 2008.Resultados:o produto final do EMR integra documentos com recursos de multimídia (texto, imagens, sinais). O EMR apresentou predominantemente vantagens e foi bem adotado pelos profissinais. A avaliação de adequação também foi possível em alguns procedimentos. Algumas desvantagens foram encontradas, como os custos de instalação, longo período de aprendizado para uso, pouca ou nenhuma padronização entre os sistemas EMR. Conclusões: o EMR é um objetivo estratégico para a integração do sistema de clínica e para permitir uma melhor qualidade de cuidados de saúde. As vantagens do EMR superam as desvantagens, produzindo um retorno positivo desse investimento para a instituição de saúde.Conclusões:o EMR é um objetivo estratégico para a integração do sistema de clínica e para permitir uma melhor qualidade de cuidados de saúde. As vantagens do EMR superam as desvantagens, produzindo um retorno positivo desse investimento para a instituição de saúde.

[Implementation and use of an electronic medical record in a department of cardiology: ten-year experience]. / Sviluppo, applicazione e valutazione di un sistema integrato gestionale e clinico nel campo delle malattie cardiovascolari: dieci anni di esperienza.

The rising of healthcare and hospital efficiency has underlined the necessity of clinical information systems. Hospitals represent complex organizations requiring control of different types of data for the management of patients and resources. A project was developed at the CNR Institute of Clinical Physiology of Pisa to produce an integration system to manage healthcare in its technological, administrative and clinical aspects, in respect of high quality in healthcare and cost-effectiveness evaluation. A networked computer-based information system was implemented to integrate different heterogeneous sources of patient data, both administrative and clinical (texts, signals, images), reaching a total integration. Data are stored into a relational database, processed and presented to healthcare personnel by network-connected clinical workstations. Epidemiological components are integrated to continuously offer evaluation processes to clinical components. From 1998 to August 2007 more than 300 stations were connected. The electronic medical records of more than 20 000 patients were recorded; more than 100 000 procedures were digitally integrated and the entire health file record and cost calculation could be obtained for each patient. In conclusion, the use of electronic medical records allowed a complete clinical data integration with improvement of overall structure efficiency and healthcare quality.

Cardiac resynchronization therapy and phase resetting of the sinoatrial node: a conjecture.

Congestive heart failure is a severe chronic disease often associated with disorders that alter the mechanisms of excitation-contraction coupling that may result in an asynchronous left ventricular motion which may further impair the ability of the failing heart to eject blood. In recent years a therapeutic approach to resynchronize the ventricles (cardiac resynchronization therapy, CRT) has been performed through the use of a pacemaker device able to provide atrial-based biventricular stimulation. Atrial lead senses the spontaneous occurrence of cells depolarization and sends the information to the generator which, in turn, after a settled delay [atrioventricular (AV) delay], sends electrical impulses to both ventricles to stimulate their synchronous contraction. Recent studies performed on heart rate behavior of chronically implanted patients at different epochs after implantation have shown that CRT can lead to sustained overall improvement of heart function with a reduction in morbidity and mortality. At this moment, however, there are no studies about CRT effects on spontaneous heart activity of chronically implanted patients. We performed an experimental study in which the electrocardiographic signal of five subjects under chronic CRT was recorded during the activity of the pacemaker programmed at different AV delays and under spontaneous cardiac activity after pacemaker deactivation. The different behavior of heart rate variability during pacemaker activity and after pacemaker deactivation suggested the hypothesis of a phase resetting mechanism induced by the pacemaker stimulus on the sinoatrial (SA) node, a phenomenon already known in literature for aggregate of cardiac cells, but still unexplored in vivo. The constraints imposed by the nature of our study (in vivo tests) made it impossible to plan an experiment to prove our hypothesis directly. We therefore considered the best attainable result would be to prove the accordance of our data to the conjecture through the use of models and physical considerations. We first used the data of literature on far-field effects of cardiac defibrillators to prove that the pacemaker impulses delivered to the two ventricles were able to induce modifications in membrane voltage at the level of the SA node. To simulate a phase resetting mechanism of the SA node, we used a Van der Pol modified model to allow the possibility of changing the refractory period and the firing frequency of the cells separately. With appropriate parameters of the model we reproduced phase response curves that can account for our experimental data. Furthermore, the simulated curves closely resemble the functional form proposed in literature for perturbed aggregate of cardiac cells. Despite the small sample of subjects investigated and the limited number of ECG recordings at different AV delays, we think we have proved the plausibility of the proposed conjecture.

Revisiting the potential of time-domain indexes in short-term HRV analysis.

In the context of HRV analysis, we evaluated the information content of two measures that can easily be derived from the classical RR time-domain indexes. The two measures are: 1) the ratio sd/rmssd, where sd is the RR standard deviation and rmssd is the root mean square of squared differences of consecutive RR beats; and 2) the ratio sd2/sd1, where sd2 and sd1 are extracted from the Poincaré plot and represent the transversal and longitudinal dispersion of the cloud of points (RR(i),RR(i)(+1)). We compared the performance of the two measures with that of the classical LF/HF ratio in a group of healthy subjects who underwent a 70 degrees upright tilt test. The goodness of the results obtained by the two measures, the simplicity of their calculation and their applicability free from a priori assumptions on the characteristics of the data are proposed to the attention of the community involved in the HRV analysis as a possible alternative to the LF/HF ratio.

Networking and data management for health care monitoring of mobile patients.

The problem of medical devices and data integration in health care is discussed and a proposal for remote monitoring of patients based on recent developments in networking and data management is presented. In particular the paper discusses the benefits of the integration of personal medical devices into a Medical Information System and how wireless sensor networks and open protocols could be employed as building blocks of a patient monitoring system.

Personality traits and heart rate variability predict long-term cardiac mortality after myocardial infarction.

AIMS: To investigate personality traits and sympatho-vagal modulation of heart rate variability (HRV) during acute myocardial infarction (AMI), assessing their relationships and their long-term prognostic value. METHODS AND RESULTS: Psychological traits and 24 h HRV were prospectively investigated in 246 patients at discharge of an AMI. Patients were followed-up to 8 years for the occurrence of cardiac death and non-fatal reinfarction. Low coping and anxiety traits associated with reduced HRV characterized the study population. At univariate analysis, low emotional sensitivity and insecurity, relative tachycardia, reduced high frequency (HF), and low frequency power and pNN50 were predictive of cardiac death at 8-year follow-up. At multivariable analysis, low emotional sensitivity and low HF power remained predictive, with a relative risk of 4.18 (P=0.003) and 2.76 (P=0.007), respectively; also the type of infarction (Q vs. non-Q) and hospital length of stay were independent predictive variables. CONCLUSION: Anxiety and emotional sensitivity were significant predictors of 8-year cardiac mortality after AMI. Reduced HF power, a recognized marker of vagal withdrawal, increased the risk.

Early assessment of heart rate variability is predictive of in-hospital death and major complications after acute myocardial infarction.

BACKGROUND: Depressed heart rate variability at acute myocardial infarction discharge is associated with poor long-term prognosis. However, its early (<48 h) predictive value has not been extensively investigated. Aim of this Multicenter Italian Study was to investigate, during acute myocardial infarction, in-hospital prognostic value of heart rate variability and its short-term evolution. METHODS: Twenty-four hour ECG monitoring was prospectively obtained on admission in 413 patients with new-onset acute myocardial infarction and repeated in 349 at discharge. Heart rate variability statistical and frequency domain indices, peak creatine kinase, echocardiographic wall motion score index and risk factors were obtained. The occurrence of cardiac death and resuscitated ventricular fibrillation were the primary end-points; cardiogenic shock, ventricular tachycardia, post-infarction angina and heart failure the secondary end-points. RESULTS: At admission, a marked reduction in heart rate variability indices was evident. Nine patients died during hospitalization and 13 were resuscitated from ventricular fibrillation. Secondary endpoints occurred in other 91 patients. At univariate analysis, low frequencies (LF), mean time interval between consecutive heart beats (RR), wall motion score index and family history of ischemic heart disease were predictive of combined primary and secondary end-points. At multivariate analysis, only LF and family history were predictive with a relative risk of 2.01 and 1.84, respectively (P<0.003). In survivors, heart rate variability indices significantly increased during hospitalization, still remaining below reference values. CONCLUSIONS: A depressed heart rate variability was present in the early phase of infarction and improved at discharge. LF power was an independent predictor of the combined unfavorable short-term events.

Effects of intravenous amlodipine on coronary hemodynamics in subjects with angiographically normal coronary arteries.

The aim of the current study was to assess the ability of amlodipine to dilate the coronary vessels in subjects with angiographically normal coronary arteries and normal left ventricular function. Ten patients, six women and four men (mean age 48 +/- 14 years, range 25-67 years) were enrolled. Coronary flow velocity and coronary perfusion pressure were invasively measured at baseline, during intracoronary adenosine (1-mg bolus) and at 5, 15, and 30 min following IV amlodipine (10 or 20 mg). Quantitative coronary angiography was performed at baseline and at 5, 15, and 30 min after amlodipine. Coronary cross-sectional area and mean coronary flow velocity progressively increased after amlodipine administration, resulting in an average increase in coronary flow at 30 min of 76%. On an individual basis, all patients but one showed a consistent trend toward a progressive coronary vasodilator effect of amlodipine over time. The peak effect of amlodipine on baseline mean coronary flow velocity was 43 +/- 12% that of adenosine. This is the first clinical study demonstrating that the IV administration of amlodipine produces a powerful coronary vasodilatation in subjects with angiographically normal coronary arteries and normal ventricular function, besides its known systemic vasodilating effects. The coronary vasodilating properties of amlodipine are particularly expressed at the microcirculatory level.