Mechanisms of Long-Duration Ventricular€Fibrillation in Human
... OBJECTIVES This study sought to determine the characteristics of human LDVF, particularly as it contrasts with short-duration VF (SDVF), and evaluate the role of Purkinje fibers in its maintenance. BACKGROUND The electrophysiological mechanisms of long-duration ventricular fibrillation (LDVF) have not ...
... OBJECTIVES This study sought to determine the characteristics of human LDVF, particularly as it contrasts with short-duration VF (SDVF), and evaluate the role of Purkinje fibers in its maintenance. BACKGROUND The electrophysiological mechanisms of long-duration ventricular fibrillation (LDVF) have not ...
Electrical and Anatomical Modeling of the Specialized Cardiac
... Figure 38. Pseudo-ECGs obtained in precordial leads in two different CCSs created with the same algorithm parameters but with different number of net-nodes in each ventricle (and different number of PMJ) ................................................................................................ ...
... Figure 38. Pseudo-ECGs obtained in precordial leads in two different CCSs created with the same algorithm parameters but with different number of net-nodes in each ventricle (and different number of PMJ) ................................................................................................ ...
EFFECTIVENESS OF A HANDHELD REMOTE ECG MONITOR
... ventricles. Figure 2.2 shows the typical lead II recording of the ECG, which has the same direction as the axis of the normal heart. ...
... ventricles. Figure 2.2 shows the typical lead II recording of the ECG, which has the same direction as the axis of the normal heart. ...
Evaluation of Diastolic Filling of Left Ventricle in Health and Disease
... in different disease states. Subsequent investigations have shown (28 –30) that mitral flow velocity curves correlate well with the first derivative of diastolic volumetric flow rates obtained by other accepted methods, such as left ventriculography, radionuclide angiography and digitized M-mode ech ...
... in different disease states. Subsequent investigations have shown (28 –30) that mitral flow velocity curves correlate well with the first derivative of diastolic volumetric flow rates obtained by other accepted methods, such as left ventriculography, radionuclide angiography and digitized M-mode ech ...
Enhanced store-operated Ca2+ entry in high glucose
... Abstract: The imbalance of intracellular Ca2+ homeostasis is a major problem in diabetic cardiomyopathy. Storeoperated Ca2+ entry (SOCE) is an important Ca2+ signalling pathway in excitable and non-excitable cells, and mediates Ca2+ influx contributing to the maintenance of intracellular Ca2+ homeos ...
... Abstract: The imbalance of intracellular Ca2+ homeostasis is a major problem in diabetic cardiomyopathy. Storeoperated Ca2+ entry (SOCE) is an important Ca2+ signalling pathway in excitable and non-excitable cells, and mediates Ca2+ influx contributing to the maintenance of intracellular Ca2+ homeos ...
cardiac potassium channel subtypes: new roles in repolarization
... atria is currently being clarified, and several findings indicate that they could constitute targets for new pharmacological treatment of atrial fibrillation. The interplay between the different K⫹ channel subtypes in both atria and ventricle is dynamic, and a significant up- and downregulation occu ...
... atria is currently being clarified, and several findings indicate that they could constitute targets for new pharmacological treatment of atrial fibrillation. The interplay between the different K⫹ channel subtypes in both atria and ventricle is dynamic, and a significant up- and downregulation occu ...
Measurement of cardiac mechanical function in isolated ventricular
... The essential contractile unit of the heart is the ventricular myocyte. Measurement of ventricular contractile function provides the most direct information on cardiac contractile function either with drug intervention or under certain pathological conditions. Over the past two decades, a plethora o ...
... The essential contractile unit of the heart is the ventricular myocyte. Measurement of ventricular contractile function provides the most direct information on cardiac contractile function either with drug intervention or under certain pathological conditions. Over the past two decades, a plethora o ...
Rate versus rhythm control in atrial fibrillation and
... AF is the most common sustained cardiac arrhythmia. Risk factors for this condition include male sex, smoking, heart failure, diabetes, arterial hypertension, left ventricular hypertrophy, valvular heart disease, myocardial infarction and advanced age. The lifetime risk of developing AF in subjects ...
... AF is the most common sustained cardiac arrhythmia. Risk factors for this condition include male sex, smoking, heart failure, diabetes, arterial hypertension, left ventricular hypertrophy, valvular heart disease, myocardial infarction and advanced age. The lifetime risk of developing AF in subjects ...
2014 Life threatening causes of syncope
... Syncope associated with structural cardiac disease or a channelopathy is associated with an increased risk of death (Ungar et al., 2010) and its treatment is often effective in reducing mortality (Khoo et al., 2013). Although this accounts for a minority of all syncope presentations, a comprehensive ...
... Syncope associated with structural cardiac disease or a channelopathy is associated with an increased risk of death (Ungar et al., 2010) and its treatment is often effective in reducing mortality (Khoo et al., 2013). Although this accounts for a minority of all syncope presentations, a comprehensive ...
in the infarcted heart potentially via increased connexin43
... (LAD) caused anterior myocardial infarction as evident by replacement of myocardium with fibrotic scar tissue 5 wk after the infarction (Fig. 1 A). Morphometric analysis of the hearts of 15 BMT animals (4 G-CSF/SCF treated and 11 untreated) killed 5 wk after induction of myocardial infarction identi ...
... (LAD) caused anterior myocardial infarction as evident by replacement of myocardium with fibrotic scar tissue 5 wk after the infarction (Fig. 1 A). Morphometric analysis of the hearts of 15 BMT animals (4 G-CSF/SCF treated and 11 untreated) killed 5 wk after induction of myocardial infarction identi ...
Geometrical considerations in cardiac electrophysiology and
... intervention has the same net effect at all heart rates we can observe that a longer action potential will exhibit a greater propensity to shorten, or prolong, for the same change in RRepol (i.e. IIonic), in comparison to an action potential of shorter initial duration. This is the geometric relatio ...
... intervention has the same net effect at all heart rates we can observe that a longer action potential will exhibit a greater propensity to shorten, or prolong, for the same change in RRepol (i.e. IIonic), in comparison to an action potential of shorter initial duration. This is the geometric relatio ...
Pharmacology Objectives 9
... 6) List the pharmacodynamic actions of digoxin, including actions on cardiac mechanical function and cardiac electrophysiology. Digoxin increases the force of myocardial contraction, a positive inotropic action seen in normal and failing hearts. Digoxin influences cardiac electrical activity by chan ...
... 6) List the pharmacodynamic actions of digoxin, including actions on cardiac mechanical function and cardiac electrophysiology. Digoxin increases the force of myocardial contraction, a positive inotropic action seen in normal and failing hearts. Digoxin influences cardiac electrical activity by chan ...
The role of endomyocardial biopsy in the management of
... Most complications are known from case reports, and therefore the precise frequency of these events is not known. The data on EMB risks are derived from several singlecenter experiences and registries that have been reported in the literature. Fowles and Mason18 reported an overall complication rate ...
... Most complications are known from case reports, and therefore the precise frequency of these events is not known. The data on EMB risks are derived from several singlecenter experiences and registries that have been reported in the literature. Fowles and Mason18 reported an overall complication rate ...
Module 3 - Cardiac Arrhythmias-Mechanisms of Arrhythmias
... ventricular fibrillation (a lethal and very high sustained heart rate, over 220. In summary, arrhythmias may be caused by many different factors, including: (1) Coronary artery disease; (2) Electrolyte imbalances in your blood (such as sodium or potassium); (3) Changes in your heart muscle; (4) Inj ...
... ventricular fibrillation (a lethal and very high sustained heart rate, over 220. In summary, arrhythmias may be caused by many different factors, including: (1) Coronary artery disease; (2) Electrolyte imbalances in your blood (such as sodium or potassium); (3) Changes in your heart muscle; (4) Inj ...
THE ACTION OF MAGNESIUM ON THE HEART
... was a progressive increase in the P-R interval as the concentration increased, until A-V block of various grades and widening of QRS appeared. If the concentration was raised sufficiently, cardiac arrest resulted. Except for the initial tachycardia, similar results were obtained in cats. In the auth ...
... was a progressive increase in the P-R interval as the concentration increased, until A-V block of various grades and widening of QRS appeared. If the concentration was raised sufficiently, cardiac arrest resulted. Except for the initial tachycardia, similar results were obtained in cats. In the auth ...
The relationship between mitral annular systolic velocity and
... EF and Sm(avg) for investigated subjects with preserved global systolic function (Figure 3). The multiple regression analysis demonstrated strong correlation between investigated variables. There was no significant difference between the subgroups regarding the strength of the correlation. Therefore ...
... EF and Sm(avg) for investigated subjects with preserved global systolic function (Figure 3). The multiple regression analysis demonstrated strong correlation between investigated variables. There was no significant difference between the subgroups regarding the strength of the correlation. Therefore ...
The Efficacy of Administration of Intravenous Magnesium Sulfate for
... When the slope of phase 4 of the cardiac action potential is increased, this causes aberrant automaticity and reduces the threshold for the action potential.2 Electrolyte abnormalities can cause deviations in the cardiac myocyte action potential. Abnormal propagation in atrial tachyarrhythmias could ...
... When the slope of phase 4 of the cardiac action potential is increased, this causes aberrant automaticity and reduces the threshold for the action potential.2 Electrolyte abnormalities can cause deviations in the cardiac myocyte action potential. Abnormal propagation in atrial tachyarrhythmias could ...
ACC/AHA/NASPE Practice Guidelines
... (5) All of the listed recommendations for implantation of a device presume the absence of inciting causes that may be eliminated without detriment to the patient (eg, nonessential drug therapy). (6) The committee endeavored to maintain consistency of recommendations in this and other previously publ ...
... (5) All of the listed recommendations for implantation of a device presume the absence of inciting causes that may be eliminated without detriment to the patient (eg, nonessential drug therapy). (6) The committee endeavored to maintain consistency of recommendations in this and other previously publ ...
Brief Review Determinants of Left Ventricular Filling and of the
... of the diastolic pressure-volume relation. However, it is now clear that changes in active relaxation of the myocardium, mechanical interaction between the ventricles, the pericardium, so-called diastolic suction, pulmonary-cardiac contact pressure, myocardial viscoelasticity, and engorgement of the ...
... of the diastolic pressure-volume relation. However, it is now clear that changes in active relaxation of the myocardium, mechanical interaction between the ventricles, the pericardium, so-called diastolic suction, pulmonary-cardiac contact pressure, myocardial viscoelasticity, and engorgement of the ...
HRS Expert Consensus Statement on the Diagnosis
... The wide range of prevalence data is likely related to a variety of factors, including patient selection as well as imaging techniques and protocols. Patients with CS have a poorer prognosis than do patients without cardiac involvement.27 In Japan, CS is reported to be responsible for as many as 85% ...
... The wide range of prevalence data is likely related to a variety of factors, including patient selection as well as imaging techniques and protocols. Patients with CS have a poorer prognosis than do patients without cardiac involvement.27 In Japan, CS is reported to be responsible for as many as 85% ...
An Analysis of the Mechanical Disadvantage of Myocardial Infarction
... strain energy function, such linear behavior can be described by a single-power strain energy function with kp = 2. Since total systolic tension is the sum of resting tension and developed tension, systolic myocardium can now be described by a two-component strain energy function with two sets of po ...
... strain energy function, such linear behavior can be described by a single-power strain energy function with kp = 2. Since total systolic tension is the sum of resting tension and developed tension, systolic myocardium can now be described by a two-component strain energy function with two sets of po ...
Expert Consensus Statement
... The wide range of prevalence data is likely related to a variety of factors, including patient selection as well as imaging techniques and protocols. Patients with CS have a poorer prognosis than do patients without cardiac involvement.27 In Japan, CS is reported to be responsible for as many as 85% ...
... The wide range of prevalence data is likely related to a variety of factors, including patient selection as well as imaging techniques and protocols. Patients with CS have a poorer prognosis than do patients without cardiac involvement.27 In Japan, CS is reported to be responsible for as many as 85% ...
A practical approach to torsade de pointes
... therapy is probably under 1%, althoughthe arrhythmiacan occur when other risk factors such as hypokalemia are present. The incidenceof torsade de pointes during treatment with other antiarrhythmics has not been estimated, but it is probably similar to that with quinidine or sotalol. When intravenous ...
... therapy is probably under 1%, althoughthe arrhythmiacan occur when other risk factors such as hypokalemia are present. The incidenceof torsade de pointes during treatment with other antiarrhythmics has not been estimated, but it is probably similar to that with quinidine or sotalol. When intravenous ...
Atrial Fibrillation - George Washington University School of Medicine
... order of preference; to avoid drug interactions, no more than one should be used. Direct-current cardioversion can be attempted as the initial strategy or used if drug therapy fails. This figure does not detail the investigation into the cause of atrial fibrillation. Strong consideration should be g ...
... order of preference; to avoid drug interactions, no more than one should be used. Direct-current cardioversion can be attempted as the initial strategy or used if drug therapy fails. This figure does not detail the investigation into the cause of atrial fibrillation. Strong consideration should be g ...
Ventricular fibrillation
Ventricular fibrillation (V-fib or VF) is a condition in which there is uncoordinated contraction of the cardiac muscle of the ventricles in the heart, making them quiver rather than contract properly. Ventricular fibrillation is the most commonly identified arrhythmia in cardiac arrest patients. While there is some activity, the lay person is usually unable to detect it by palpating (feeling) the major pulse points of the carotid and femoral arteries. Such an arrhythmia is only confirmed by electrocardiography. Ventricular fibrillation is a medical emergency that requires prompt Advanced Life Support interventions. If this arrhythmia continues for more than a few seconds, it will likely degenerate further into asystole (""flatline""). This condition results in cardiogenic shock and cessation of effective blood circulation. As a consequence, sudden cardiac death (SCD) will result in a matter of minutes. If the patient is not revived after a sufficient period (within roughly 5 minutes at room temperature), the patient could sustain irreversible brain damage and possibly become brain-dead, due to the effects of cerebral hypoxia. On the other hand, death often occurs if sinus rhythm is not restored within 90 seconds of the onset of VF, especially if it has degenerated further into asystole.