New Insights into Mechanisms of Atrial Fibrillation
... persist (Moe et al. 1964). The shortening of the refractory period of atrial myocytes and the slowing of conduction velocity – salient features of electrical remodeling – both help to stabilize the arrhythmia by decreasing circuit size. This theory has support in the experimental work of Allessie et ...
... persist (Moe et al. 1964). The shortening of the refractory period of atrial myocytes and the slowing of conduction velocity – salient features of electrical remodeling – both help to stabilize the arrhythmia by decreasing circuit size. This theory has support in the experimental work of Allessie et ...
Kavasmaa, Mervi Haapsamo, Luc Mertens and James
... as required. A catheter was inserted into the ewe’s external left jugular vein to serve as a permanent intravenous line, and an auricular artery was cannulated for blood pressure (BP) and heart rate monitoring. Mechanical ventilation was maintained throughout the surgical procedure. A midline laparo ...
... as required. A catheter was inserted into the ewe’s external left jugular vein to serve as a permanent intravenous line, and an auricular artery was cannulated for blood pressure (BP) and heart rate monitoring. Mechanical ventilation was maintained throughout the surgical procedure. A midline laparo ...
Anti-Inflammatory Strategies for Ventricular Remodeling Following ST-Segment Elevation Acute Myocardial Infarction
... Mechanisms of action for the different anti-inflammatory treatments. (Upper left) Glucocorticoids bind a receptor (GR) in the cytosol that homodimerizes and translocates to the nucleus to exert anti-inflammatory effects, whereas other nongenomic effects are related to endothelial nitric oxide synthase ...
... Mechanisms of action for the different anti-inflammatory treatments. (Upper left) Glucocorticoids bind a receptor (GR) in the cytosol that homodimerizes and translocates to the nucleus to exert anti-inflammatory effects, whereas other nongenomic effects are related to endothelial nitric oxide synthase ...
Effect of Preload Reduction by Hemodialysis on Left Ventricular
... MRI can be used in humans and represents an assessment “gold standard.” This technique is only used in a few medical centers in Taiwan. Two-dimensional speckle tracking imaging echocardiography (2D-STE) has provided a new opportunity for the noninvasive evaluation of LV torsional deformation.11-16 H ...
... MRI can be used in humans and represents an assessment “gold standard.” This technique is only used in a few medical centers in Taiwan. Two-dimensional speckle tracking imaging echocardiography (2D-STE) has provided a new opportunity for the noninvasive evaluation of LV torsional deformation.11-16 H ...
Catheter Ablation of Supraventricular and Ventricular Arrhythmias
... recording relative to the delta wave onset may also indicate an optimal ablation site.18 The atrial insertion of an accessory pathway is usually localized by identifying the site of the shortest ventriculoatrial (VA) interval during ventricular pacing or during circus movement tachycardia or by reco ...
... recording relative to the delta wave onset may also indicate an optimal ablation site.18 The atrial insertion of an accessory pathway is usually localized by identifying the site of the shortest ventriculoatrial (VA) interval during ventricular pacing or during circus movement tachycardia or by reco ...
The Fontan circulation: who controls cardiac output?
... or tachycardia, normalisation of heart rate to physiological rate will improve output and hemodynamics w13, 14x. Fontan patients exhibit what is called ‘chronotropic incompetence’ during exercise with a heart rate consistently lower than normal controls, and this has typically been attributed to abn ...
... or tachycardia, normalisation of heart rate to physiological rate will improve output and hemodynamics w13, 14x. Fontan patients exhibit what is called ‘chronotropic incompetence’ during exercise with a heart rate consistently lower than normal controls, and this has typically been attributed to abn ...
Cardiac magnetic resonance imaging in congenital heart disease
... signal of an area of similar size to the vessel of interest in nearby stationary tissue. Some newer post-processFigure 3a: A patient with transannular patch repair and ventricular septal defect (VSD) closure for tetralogy of Fallot and residual pulmonary regurgitation (PR). Still frame of a SSFP RVO ...
... signal of an area of similar size to the vessel of interest in nearby stationary tissue. Some newer post-processFigure 3a: A patient with transannular patch repair and ventricular septal defect (VSD) closure for tetralogy of Fallot and residual pulmonary regurgitation (PR). Still frame of a SSFP RVO ...
Acute Myocardial Infarction: A Century of Progress
... agent. In the TIMI- 25 trial, Antman et al. demonstrated the superiority of the subcutaneous administration of a low molecular weight heparin when compared to intravenous administration of unfractionated heparin. (Figure 6, see p. 187) (Antman et al., 2006). Building on the benefit of adding aspirin ...
... agent. In the TIMI- 25 trial, Antman et al. demonstrated the superiority of the subcutaneous administration of a low molecular weight heparin when compared to intravenous administration of unfractionated heparin. (Figure 6, see p. 187) (Antman et al., 2006). Building on the benefit of adding aspirin ...
PDF file - Via Medica Journals
... parasympathetic fibres were found in the lamina muscularis of the right ventricle. Similar results were also obtained by Hoover et al. [26], who studied the heart of the guinea pig, and Yasuhara et al. [67], who studied the rat. Cardiac plexuses contain clusters of neurons forming a polymorphic syst ...
... parasympathetic fibres were found in the lamina muscularis of the right ventricle. Similar results were also obtained by Hoover et al. [26], who studied the heart of the guinea pig, and Yasuhara et al. [67], who studied the rat. Cardiac plexuses contain clusters of neurons forming a polymorphic syst ...
Cardiac sympathetic afferent stimulation impairs - AJP
... the left ventricle. A piece of filter paper (3 ⫻ 3 mm) containing capsaicin (0.4 g in 2 l) was applied to the epicardial surface of the anterior surface of the left ventricle. Each drug was applied for ⬃2 min until the end of the baroreflex test, and then the filter paper was removed and the epica ...
... the left ventricle. A piece of filter paper (3 ⫻ 3 mm) containing capsaicin (0.4 g in 2 l) was applied to the epicardial surface of the anterior surface of the left ventricle. Each drug was applied for ⬃2 min until the end of the baroreflex test, and then the filter paper was removed and the epica ...
Left ventricular systolic performance during prolonged strenuous
... diastolic ventricular interaction (with or without pericardial constraint) may have reduced LV compliance and filling. This hypothesis does not seem likely, however, as the LV end-diastolic cavity area decreased during the first 90 minutes of exercise and returned to baseline values at the cessation ...
... diastolic ventricular interaction (with or without pericardial constraint) may have reduced LV compliance and filling. This hypothesis does not seem likely, however, as the LV end-diastolic cavity area decreased during the first 90 minutes of exercise and returned to baseline values at the cessation ...
Chapter_009
... Describe how local and central control mechanisms regulate the heart and vascular systems. Describe how the cardiovascular system coordinates its functions under normal and abnormal conditions. Copyright © 2013, 2009, 2003, 1999, 1995, 1990, 1982, 1977, 1973, 1969 by Mosby, an imprint of Elsevier In ...
... Describe how local and central control mechanisms regulate the heart and vascular systems. Describe how the cardiovascular system coordinates its functions under normal and abnormal conditions. Copyright © 2013, 2009, 2003, 1999, 1995, 1990, 1982, 1977, 1973, 1969 by Mosby, an imprint of Elsevier In ...
Reproducibility of Echocardiographic Left Ventricular
... An additional requirement for timing of echocardiographic measurements, particularly of end-diastolic dimensions, is the simultaneous recording of QRS complexes with readily identifiable onset and peak of deflections. These criteria were found by Schieken et al.1 to result in high reproducibility of ...
... An additional requirement for timing of echocardiographic measurements, particularly of end-diastolic dimensions, is the simultaneous recording of QRS complexes with readily identifiable onset and peak of deflections. These criteria were found by Schieken et al.1 to result in high reproducibility of ...
Therapeutic effect of taurine in congestive heart failure: A double
... were calculated from the mean of measurement made on 5 consecutive cardiac cycles for sinus rhythm, and 8 cardiac cycles chosen at random whose preceding R-R interval was over 800 ms for atrial fibrillation (Lewis ef al., 1974). Atrial fibrillation produces alteration in the usual relationship of th ...
... were calculated from the mean of measurement made on 5 consecutive cardiac cycles for sinus rhythm, and 8 cardiac cycles chosen at random whose preceding R-R interval was over 800 ms for atrial fibrillation (Lewis ef al., 1974). Atrial fibrillation produces alteration in the usual relationship of th ...
Effect of an Aspartame-Ethanol Mixture on Daphnia
... the medulla (Karpas, 1916). The medulla is responsible for controlling breathing, heart rate and other basic involuntary functions in the body. By depressing this part of the brain, alcohol can also reduce heart rate. Since the heart rate is modulated by different parts of the brain, the heart rate ...
... the medulla (Karpas, 1916). The medulla is responsible for controlling breathing, heart rate and other basic involuntary functions in the body. By depressing this part of the brain, alcohol can also reduce heart rate. Since the heart rate is modulated by different parts of the brain, the heart rate ...
![Effects of an Increase in Intracellular Free [Mg2+] After](http://s1.studyres.com/store/data/021064513_1-ab802370249f85ccc8243f1fa47b2f64-300x300.png)
Effects of an Increase in Intracellular Free [Mg2+] After
... stability constants reported by Fabiato,18 which were corrected for 37°C and pH 7.15. To evaluate the effect of an increase in free [Mg2>] on SR activity, the free [Mg>] was either 0.6 mM for control SR or 1.5 mM for stunned SR. These free [Mg2+] were chosen to represent the ionic conditions in the ...
... stability constants reported by Fabiato,18 which were corrected for 37°C and pH 7.15. To evaluate the effect of an increase in free [Mg2>] on SR activity, the free [Mg>] was either 0.6 mM for control SR or 1.5 mM for stunned SR. These free [Mg2+] were chosen to represent the ionic conditions in the ...
EFFECTS OF EXERCISE TRAINING ON MAXIMAL OXYGEN
... The management for chronic heart failure is a combination of drugs and lifestyle changes. Because the concepts of heart failure mechanisms and treatment have greatly changed over the past decades, nowadays patients with this disease are being physically more active than ever before (Klocek et al. 20 ...
... The management for chronic heart failure is a combination of drugs and lifestyle changes. Because the concepts of heart failure mechanisms and treatment have greatly changed over the past decades, nowadays patients with this disease are being physically more active than ever before (Klocek et al. 20 ...
PDF - Circulation
... changes noted with aging are related to disuse and normalize with increased activity.39 This study had two purposes. The first was to determine whether rigorously screened sedentary healthy older men indeed do have reduced heart rate, blood pressure, ejection fraction, and cardiac output responses t ...
... changes noted with aging are related to disuse and normalize with increased activity.39 This study had two purposes. The first was to determine whether rigorously screened sedentary healthy older men indeed do have reduced heart rate, blood pressure, ejection fraction, and cardiac output responses t ...
insight review articles
... organs (including the kidneys, mesenteric circulation and the heart itself), potentially leading to infarction. The thromboembolic risk is reduced by administration of oral anticoagulant drugs, but at the price of an increased risk of bleeding complications. These considerations probably account for ...
... organs (including the kidneys, mesenteric circulation and the heart itself), potentially leading to infarction. The thromboembolic risk is reduced by administration of oral anticoagulant drugs, but at the price of an increased risk of bleeding complications. These considerations probably account for ...
Association of Imaging Markers of Myocardial Fibrosis With
... Background—Metabolic and vascular disturbances contribute to diabetic cardiomyopathy, but the role of interstitial fibrosis in early disease is unproven. We sought to assess the relationship between imaging markers of diffuse fibrosis and myocardial dysfunction and to link this to possible causes of ...
... Background—Metabolic and vascular disturbances contribute to diabetic cardiomyopathy, but the role of interstitial fibrosis in early disease is unproven. We sought to assess the relationship between imaging markers of diffuse fibrosis and myocardial dysfunction and to link this to possible causes of ...
Left Atrial Enlargement in Young High
... high static and dynamic exertion induce the morphologic adaptation of the heart to the highest degree. Therefore, the biggest LA enlargement can be expected in those groups of athletes (Pelliccia et al., 2005). The hypothesis of the study was that LA enlargement in athletes was physiologic, fitnessr ...
... high static and dynamic exertion induce the morphologic adaptation of the heart to the highest degree. Therefore, the biggest LA enlargement can be expected in those groups of athletes (Pelliccia et al., 2005). The hypothesis of the study was that LA enlargement in athletes was physiologic, fitnessr ...
Transcatheter Closure of Atrial Septal Defect in Ebstein`s Anomaly
... develop systemic desaturation and risk of systemic embolization due to right-to-left shunting. Before deterioration of right-side heart function and tricuspid regurgitation, early intervention to repair the interatrial communication might improve outcomes. In our report, transcatheter Amplatzer sept ...
... develop systemic desaturation and risk of systemic embolization due to right-to-left shunting. Before deterioration of right-side heart function and tricuspid regurgitation, early intervention to repair the interatrial communication might improve outcomes. In our report, transcatheter Amplatzer sept ...
Clinical Medicine Insights: Cardiology Arrhythmogenic Right
... arrhythmia is sustained or nonsustained monomorphic VT that originates in the RV and therefore has a left bundle branch block (LBBB) morphology. Alternatively, in some cases where the LV is involved, VT could present with a right bundle branch block (RBBB) morphology. These symptoms are usually exer ...
... arrhythmia is sustained or nonsustained monomorphic VT that originates in the RV and therefore has a left bundle branch block (LBBB) morphology. Alternatively, in some cases where the LV is involved, VT could present with a right bundle branch block (RBBB) morphology. These symptoms are usually exer ...
NEW DEVELOPMENTS iN ECHOCARDiOGRAPHy
... causing bubble destruction, the MI needs to be decreased significantly and usually needs to be <0.3. A low MI will minimize micro-bubble destruction, but, as previously mentioned, will generate only a very weak backscattered signal. Therefore, more sensitive contrast detection methods have to be use ...
... causing bubble destruction, the MI needs to be decreased significantly and usually needs to be <0.3. A low MI will minimize micro-bubble destruction, but, as previously mentioned, will generate only a very weak backscattered signal. Therefore, more sensitive contrast detection methods have to be use ...
Electrocardiography
Electrocardiography (ECG or EKG*) is the process of recording the electrical activity of the heart over a period of time using electrodes placed on a patient's body. These electrodes detect the tiny electrical changes on the skin that arise from the heart muscle depolarizing during each heartbeat.In a conventional 12 lead ECG, ten electrodes are placed on the patient's limbs and on the surface of the chest. The overall magnitude of the heart's electrical potential is then measured from twelve different angles (""leads"") and is recorded over a period of time (usually 10 seconds). In this way, the overall magnitude and direction of the heart's electrical depolarization is captured at each moment throughout the cardiac cycle. The graph of voltage versus time produced by this noninvasive medical procedure is referred to as an electrocardiogram (abbreviated ECG or EKG).During each heartbeat, a healthy heart will have an orderly progression of depolarization that starts with pacemaker cells in the sinoatrial node, spreads out through the atrium, passes through the atrioventricular node down into the bundle of His and into the Purkinje fibers spreading down and to the left throughout the ventricles. This orderly pattern of depolarization gives rise to the characteristic ECG tracing. To the trained clinician, an ECG conveys a large amount of information about the structure of the heart and the function of its electrical conduction system. Among other things, an ECG can be used to measure the rate and rhythm of heartbeats, the size and position of the heart chambers, the presence of any damage to the heart's muscle cells or conduction system, the effects of cardiac drugs, and the function of implanted pacemakers.