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Automatic detection of pulse morphology patterns & cardiac risks  [PDF]
Rajani R. Joshi, Ganesh B. Nawsupe, Smita P. Wangikar
Journal of Biomedical Science and Engineering (JBiSE) , 2012, DOI: 10.4236/jbise.2012.56041
Abstract: Analysis of arterial pulse waveforms is important for non-invasive diagnosis of cardiovascular functions. Large samples of IPG signal records of radial arterial pulse show presence of eight different types of shapes (morphological patterns) in the pulse waveforms. In this paper we present an efficient computational method for automatic identification of these morphological patterns. Our algorithm uses likelihood ratio of cumulative periodogram of pulse signals and some geometrical criteria. The algorithm is presented with necessary details on signal processing aspects. Results for a large sample of pulse records of adult Indian subjects show high accuracy of our algorithm in detecting pulse-morphology patterns. Variation of pulse-morphology with respect to time is also analyzed using this algorithm. We have identified some characteristic features of pulse-morphology variation in patients of certain cardiac problems, hypertension, and diabetes. These are found relevant and significant in terms of physiological interpretation of the associated shapes of pulse waveforms. Importance of these findings is highlighted along with discussion on overall scope of our study in automatic analysis of heart rate variability and in other applications for non-invasive prognosis/diagnosis.
The Risks of Inappropriateness in Cardiac Imaging  [PDF]
Eugenio Picano
International Journal of Environmental Research and Public Health , 2009, DOI: 10.3390/ijerph6051649
Abstract: The immense clinical and scientific benefits of cardiovascular imaging are well-established, but are also true that 30 to 50% of all examinations are partially or totally inappropriate. Marketing messages, high patient demand and defensive medicine, lead to the vicious circle of the so-called Ulysses syndrome. Mr. Ulysses, a typical middle-aged “worried-well” asymptomatic subject with an A-type coronary personality, a heavy (opium) smoker, leading a stressful life, would be advised to have a cardiological check-up after 10 years of war. After a long journey across imaging laboratories, he will have stress echo, myocardial perfusion scintigraphy, PET-CT, 64-slice CT, and adenosine-MRI performed, with a cumulative cost of >100 times a simple exercise-electrocardiography test and a cumulative radiation dose of >4,000 chest x-rays, with a cancer risk of 1 in 100. Ulysses is tired of useless examinations, exorbitant costs. unaffordable even by the richest society, and unacceptable risks.
How low is too low? Cardiac risks with anemia
Samir M Fakhry, Paola Fata
Critical Care , 2004, DOI: 10.1186/cc2845
Abstract: For years many physicians firmly believed that a hemoglobin of 10 g/dl and a hematocrit of 30% represented desirable goals in anemic patients, especially those undergoing surgical procedures and those with cardiac disease. Despite the paucity of objective data to support this contention, the so-called '10/30 rule' persisted until recently [1]. Most authorities attribute this bias to a 1942 report by Adams and Lundy [2] in which they recommended a hemoglobin of 10 g/dl and a hematocrit of 30% in the perioperative setting based on their clinical experience. Recent studies [3-7] have provided compelling evidence against the 10/30 rule in critically ill patients as well as in the perioperative period. Despite these data, many clinicians continue to provide transfusion using a hematocrit of 30% as a 'transfusion trigger' [8]. However, current practice and available evidence is gradually shifting from transfusing to an arbitrary hemoglobin (10/30) to achieving a level of hemoglobin necessary to meet the patient's tissue oxygen demands [9,10].The optimal hemoglobin level is more closely approximated by physiologic measurements [11]. In patients who are not critically ill, most studies have demonstrated that a substantially lower hemoglobin level (7 g/dl) can be tolerated if normovolemia is maintained. Experience in Jehovah's Witness patients has allowed an assessment of human tolerance of severe acute anemia and demonstrated the feasibility of survival in the case of very low hematocrit [12-18]. In a review of 61 medical and surgical reports published from 1970 to 1993, Viele and Weiskopf [17] identified 50 deaths attributed to anemia in untransfused Jehovah's Witnesses with hemoglobin concentrations of 8 g/dl or less, or hematocrit of 24% or less. Of the 50 deaths, 23 were thought to be primarily due to anemia. Except for three patients who died after cardiac surgery, all patients whose deaths were attributed to anemia died with hemoglobin concentrations of 5 g/dl or less
Minimizing cardiac surgery risks in a Hepatitis C patient: Changing surgical strategy after evaluation by modern imaging technologies
Felix Kur, Andres Beiras-Fernandez, Martin Oberhoffer, Konstantin Nikolaou, et al.
Therapeutics and Clinical Risk Management , 2009, DOI: http://dx.doi.org/10.2147/TCRM.S5496
Abstract: imizing cardiac surgery risks in a Hepatitis C patient: Changing surgical strategy after evaluation by modern imaging technologies Case report (2961) Total Article Views Authors: Felix Kur, Andres Beiras-Fernandez, Martin Oberhoffer, Konstantin Nikolaou, et al. Published Date May 2009 Volume 2009:5 Pages 409 - 412 DOI: http://dx.doi.org/10.2147/TCRM.S5496 Felix Kur1, Andres Beiras-Fernandez1, Martin Oberhoffer1, Konstantin Nikolaou2, Calin Vicol1, Bruno Reichart1 1Department of Cardiac Surgery, 2Department of Radiology, University Hospital Grosshadern, Munich, Germany Abstract: Minimizing operative risks for the surgical team in infectious patients is crucial. We report on a patient suffering from Hepatitis C undergoing re-operative aortic valve and ascending aorta replacement for aortic aneurysm and paravalvular leakage due to recurrent endocarditis of a Smeloff–Cutter aortic ball prosthesis. Preoperative multi-slice computed tomography and real-time three-dimensional echocardiography proved helpful in changing operative strategy by detecting a previously unknown aortic aneurysm, assessing its extent, and demonstrating the close proximity of the right coronary artery, right ventricle, and the aortic aneurysm to the sternum. Thus, cardiopulmonary bypass was instituted via the femoral vessels, instead of conventionally. Location, morphology, and extent of the paravalvular defect could also be assessed.
Minimizing cardiac surgery risks in a Hepatitis C patient: Changing surgical strategy after evaluation by modern imaging technologies
Felix Kur,Andres Beiras-Fernandez,Martin Oberhoffer,Konstantin Nikolaou
Therapeutics and Clinical Risk Management , 2009,
Abstract: Felix Kur1, Andres Beiras-Fernandez1, Martin Oberhoffer1, Konstantin Nikolaou2, Calin Vicol1, Bruno Reichart11Department of Cardiac Surgery, 2Department of Radiology, University Hospital Grosshadern, Munich, GermanyAbstract: Minimizing operative risks for the surgical team in infectious patients is crucial. We report on a patient suffering from Hepatitis C undergoing re-operative aortic valve and ascending aorta replacement for aortic aneurysm and paravalvular leakage due to recurrent endocarditis of a Smeloff–Cutter aortic ball prosthesis. Preoperative multi-slice computed tomography and real-time three-dimensional echocardiography proved helpful in changing operative strategy by detecting a previously unknown aortic aneurysm, assessing its extent, and demonstrating the close proximity of the right coronary artery, right ventricle, and the aortic aneurysm to the sternum. Thus, cardiopulmonary bypass was instituted via the femoral vessels, instead of conventionally. Location, morphology, and extent of the paravalvular defect could also be assessed.Keywords: aortic valve replacement, aorta, surgery, risk analysis
Automatic Bubble Detection in Cardiac Video Imaging
Parlak, Ismail Burak;Ademoglu, Ahmet;Egi, Salih Murat;Balestra, Costantino;Germonpre, Peter;Marroni, Alessandro;
Polibits , 2011,
Abstract: bubble recognition is a challenging problem in a broad range from mechanics to medicine. these gas-filled structures whose pattern and morphology alter in their surrounding environment would be counted either manually or with computational recognition procedures. in cardiology, user dependent bubble detection and temporal counting in videos require special trainings and experience due to ultra fast movement, inherent noise and video quality. in this study, we propose an efficient recognition routine to increase the objectivity of emboli detection. firstly, we started to compare five different methods on two synthetic data sets emulating cardiac chamber environment with increasing speckle noise levels. secondly, real echocardiographic video records were segmented by variational active contours and left atria (la) were extracted. finally, three successful methods in simulation were applied to las in order to reveal candidate bubbles on video frames. our detection rate of proposed method was 95.7% and the others were 86.2% and 88.3%. we conclude that our approach would be useful in long lasting video processing and would be applied in other disciplines.
The Effects of Traditional Dual Chamber Cardiac Permanent Pacemaker on Arterial Distensibility Using Carotid-Femoral (Aortic) Pulse Wave Velocity in Patients with Angiographically Normal Coronary Arteries
Mustafa Y?ld?z,Banu ?ahin Y?ld?z,Mesut ?eker,Hakan Hasdemir
Ko?uyolu Kalp Dergisi , 2012,
Abstract: Introduction: The traditional dual chamber cardiac permanent pacemakers are widely used for symptomatic bradycardia. Pulse wave velocity (PWV) is an index of arterial stiffness and a marker of cardiovascular events. This study aims to investigate arterial distensibility using carotid-femoral (aortic) PWV measurements in patients with traditional dual chamber cardiac permanent pacemakers and angiographically normal coronary arteries. Patients and Methods: We recruited 17 paced patients and 17 age and sex matched controls. Aortic PWV was determined using an automatic device, the Complior Colson (France), which allowed on-line pulse wave recording and automatic calculation of PWV. PWV is calculated from measurements of pulse transit time and the distance travelled by the pulse between two recording sites, according to the following formula: PWV (m/s) = Distance (m) / Transit time (s)Results: The carotid-femoral PWV (10.20 ± 2.00, 9.06 ± 0.94 m/s, p= 0.04) was increased in patients with dual chamber pacing as compared with age and sex-matched control group. Multiple regression analysis between PWV and clinical parameters (age, sex, weight, height, systolic blood pressure, diastolic blood pressure, pulse pressure, mean blood pressure, heart rate) showed that PWV correlated positively with age (r2= 0.31; p= 0.007). Similar results were obtained in the paced patients (age, r2= 0.36; p= 0.03) and control (age, r2= 0.33; p= 0.04) subgroups when analyzed separately.Conclusion: Arterial distensibility is increased in patients with traditional dual chamber cardiac permanent pacemakers and angiographically normal coronary arteries, as compared with age and sex matched controls.
Automatic Assessment of Socioeconomic Impact on Cardiac Rehabilitation  [PDF]
Mireia Calvo,Laia Subirats,Luigi Ceccaroni,José María Maroto,Carmen de Pablo,Felip Miralles
International Journal of Environmental Research and Public Health , 2013, DOI: 10.3390/ijerph10115266
Abstract: Disability-Adjusted Life Years (DALYs) and Quality-Adjusted Life Years (QALYs), which capture life expectancy and quality of the remaining life-years, are applied in a new method to measure socioeconomic impacts related to health. A 7-step methodology estimating the impact of health interventions based on DALYs, QALYs and functioning changes is presented. It relates the latter (1) to the EQ-5D-5L questionnaire (2) to automatically calculate the health status before and after the intervention (3). This change of status is represented as a change in quality of life when calculating QALYs gained due to the intervention (4). In order to make an economic assessment, QALYs gained are converted to DALYs averted (5). Then, by inferring the cost/DALY from the cost associated to the disability in terms of DALYs lost (6) and taking into account the cost of the action, cost savings due to the intervention are calculated (7) as an objective measure of socioeconomic impact. The methodology is implemented in Java. Cases within the framework of cardiac rehabilitation processes are analyzed and the calculations are based on 200 patients who underwent different cardiac-rehabilitation processes. Results show that these interventions result, on average, in a gain in QALYs of 0.6 and a cost savings of 8,000 €.
Equipment review: New techniques for cardiac output measurement – oesophageal Doppler, Fick principle using carbon dioxide, and pulse contour analysis
Christine Berton, Bernard Cholley
Critical Care , 2002, DOI: 10.1186/cc1492
Abstract: Intensive and perioperative care share a common goal, namely to maintain 'adequate' organ perfusion throughout the body during the time course of critical illness or surgery. Adequate organ perfusion implies two different physical properties: perfusion pressure that is sufficiently high to force blood into the capillaries of all organs; and sufficient flow to deliver oxygen and substrates, and to remove carbon dioxide and other metabolic byproducts. However, in many instances the only aspect of perfusion that is carefully monitored is pressure, whereas flow is simply ignored. One of the reasons for this may be related to the difficulties encountered in obtaining flow measurements. Indeed, in many centres the only way to obtain a measure of cardiac output is to use the thermodilu-tion technique through a pulmonary artery catheter. The difficulties and risks associated with pulmonary artery catheter insertion may account, in part, for the lack of routine cardiac output monitoring in every patient. New emerging techniques can provide a measure of cardiac output less invasively than is the case with a pulmonary artery catheter.The purpose of the present review is to provide an overview of the new cardiac output measurement techniques, with an emphasis on their principles of operation and their respective limitations. We review methods based on Doppler velocime-try of the descending aorta, the Fick principle applied to carbon dioxide, and arterial pulse contour analysis.The oesophageal Doppler technique is based on measurement of blood flow velocity in the descending aorta by means of a Doppler transducer (4 MHz continuous or 5 MHz pulsed wave, according to the type of device) at the tip of a flexible probe. The probe may be introduced orally in anaesthetized, mechanically ventilated patients. Following introduction of the probe, it is advanced gently until the tip is located approximately at the mid-thoracic level; it is then rotated so that the transducer faces the aor
Pulse contour analysis after normothermic cardiopulmonary bypass in cardiac surgery patients
Michael Sander, Christian von Heymann, Achim Foer, Vera von Dossow, Joachim Grosse, Simon Dushe, Wolfgang F Konertz, Claudia D Spies
Critical Care , 2005, DOI: 10.1186/cc3903
Abstract: After ethical approval and written informed consent, data of 45 patients were analyzed during this prospective study. During coronary artery bypass graft surgery, the aortic transpulmonary thermodilution cardiac output (COPiCCOtherm) and the COPACtherm were determined in all patients. Prior to surgery, the COPiCCOpulse was calibrated by triple transpulmonary thermodilution measurement of the COPiCCOtherm. After termination of CPB, the COPiCCOpulse was documented. Both COPACtherm and COPiCCOtherm were also simultaneously determined and documented.Regression analysis between COPACtherm and COPiCCOtherm prior to CPB showed a correlation coefficient of 0.95 (P < 0.001), and after CPB showed a correlation coefficient of 0.82 (P < 0.001). Bland-Altman analysis showed a mean bias and limits of agreement of 0.0 l/minute and -1.4 to +1.4 l/minute prior to CPB and of 0.3 l/minute and -1.9 to +2.5 l/minute after CPB, respectively. Regression analysis of COPiCCOpulse versus COPiCCOtherm and of COPiCCOpulse versus COPACtherm after CPB showed a correlation coefficient of 0.67 (P < 0.001) and 0.63 (P < 0.001), respectively. Bland-Altman analysis showed a mean bias and limits of agreement of -1.1 l/minute and -1.9 to +4.1 l/minute versus -1.4 l/minute and -4.8 to +2.0 l/minute, respectively.We observed an excellent correlation of COPiCCOtherm and COPACtherm measurement prior to CPB. Pulse contour analysis did not yield reliable results with acceptable accuracy and limits of agreement under difficult conditions after weaning from CPB in cardiac surgical patients. The pulse contour analysis thus should be re-calibrated as soon as possible, to prevent false therapeutic consequences.Measurement of cardiac output (CO) is widely used in cardiac surgical patients. Over recent decades the main device for determination of CO has been the pulmonary artery catheter (PAC). The use of the PAC has been decreasing over recent years in surgical and cardiac surgical patients, however, as the benefi
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