Optical mapping of activation patterns in an animal - AJP
... performed and the heart was exposed in a pericardial cradle. The caval veins were isolated and loose ligatures were placed around the inferior and superior vena cavae. The heart was rapidly excised and placed in cold oxygenated Tyrode solution containing 1,500 U/l heparin sodium. The heart was then ...
... performed and the heart was exposed in a pericardial cradle. The caval veins were isolated and loose ligatures were placed around the inferior and superior vena cavae. The heart was rapidly excised and placed in cold oxygenated Tyrode solution containing 1,500 U/l heparin sodium. The heart was then ...
Myosin Types and Fiber Types in Cardiac Muscle. III. Nodal
... is summarized in Fig. 1. As previously described (15, 36), anfi-bA stained all atrial fibers and a minor population of ventricular fibers (Fig. 1 a), whereas anti-bV stained all ventricular fibers and a minor population of atrial fibers (Fig. I c). In contrast, anti-bF did not react with atrial or v ...
... is summarized in Fig. 1. As previously described (15, 36), anfi-bA stained all atrial fibers and a minor population of ventricular fibers (Fig. 1 a), whereas anti-bV stained all ventricular fibers and a minor population of atrial fibers (Fig. I c). In contrast, anti-bF did not react with atrial or v ...
CORONARY ARTERIES
... depolarization. There are pacemaker cells here as well. They can create an impulse, but the rate is usually only 20-40 beats per minute. ...
... depolarization. There are pacemaker cells here as well. They can create an impulse, but the rate is usually only 20-40 beats per minute. ...
Basic ECG Rhythm Interpretation
... dioxide and other wastes removed. This is accomplished through coronary circulation. The heart is supplied by 2 major coronary arteries: the right coronary artery (RCA) and the left coronary artery (LCA). These arteries arise from the aorta immediately distal to the aortic valve. Coronary perfusion ...
... dioxide and other wastes removed. This is accomplished through coronary circulation. The heart is supplied by 2 major coronary arteries: the right coronary artery (RCA) and the left coronary artery (LCA). These arteries arise from the aorta immediately distal to the aortic valve. Coronary perfusion ...
Lead I
... If a different paper speed is used, calculations will have to be modified appropriately. Calculate atrial and ventricular rates separately if they are different (e.g. complete heart block). There are multiple methods to estimate the rate: For regular rhythms: Rate = 300 / number of large squares in ...
... If a different paper speed is used, calculations will have to be modified appropriately. Calculate atrial and ventricular rates separately if they are different (e.g. complete heart block). There are multiple methods to estimate the rate: For regular rhythms: Rate = 300 / number of large squares in ...
Myosin Types and Fiber Types in Cardiac Muscle
... is summarized in Fig. 1. As previously described (15, 36), anfi-bA stained all atrial fibers and a minor population of ventricular fibers (Fig. 1 a), whereas anti-bV stained all ventricular fibers and a minor population of atrial fibers (Fig. I c). In contrast, anti-bF did not react with atrial or v ...
... is summarized in Fig. 1. As previously described (15, 36), anfi-bA stained all atrial fibers and a minor population of ventricular fibers (Fig. 1 a), whereas anti-bV stained all ventricular fibers and a minor population of atrial fibers (Fig. I c). In contrast, anti-bF did not react with atrial or v ...
Atrial Fibrillation in the 21st Century: A Current Understanding of
... specific mention has been made of the duration of persistent T2DM necessary to pose a risk for the development of AF. A recent population-based case-control study of approximately 3600 participants suggested that persistent uncontrolled T2DM (based on hemoglobin A1c level) might pose a cumulative ris ...
... specific mention has been made of the duration of persistent T2DM necessary to pose a risk for the development of AF. A recent population-based case-control study of approximately 3600 participants suggested that persistent uncontrolled T2DM (based on hemoglobin A1c level) might pose a cumulative ris ...
atrial fibrillation
... older, diabetes mellitus, and history of stroke or transient ischemic attack (TIA). In the CHADS2 scoring system, cardiac failure, hypertension, age, age of 75 year or older, and diabetes are each assigned one point; a stroke or a TIA are assigned two points. The relative risk and the treatment deci ...
... older, diabetes mellitus, and history of stroke or transient ischemic attack (TIA). In the CHADS2 scoring system, cardiac failure, hypertension, age, age of 75 year or older, and diabetes are each assigned one point; a stroke or a TIA are assigned two points. The relative risk and the treatment deci ...
Reservoir and Conduit Function of the Right Atrium - AJP
... The right atrium is a dynamic structure whose role is to assist filling of the right ventricle. Ideally, the right atrium should transfer a high volume of blood rapidly to the ventricle at low pressure to prevent peripheral edema and hepatic congestion. The three components of atrial function are: 1 ...
... The right atrium is a dynamic structure whose role is to assist filling of the right ventricle. Ideally, the right atrium should transfer a high volume of blood rapidly to the ventricle at low pressure to prevent peripheral edema and hepatic congestion. The three components of atrial function are: 1 ...
Understanding Arrhythmias and your EP Procedure
... • Anti-clotting agents, or anti-coagulants, prevent blood clots that can cause heart attack and stroke. Anti-coagulants are commonly used for patients with atrial fibrillation or mechanical heart valves. Although vital, these medicines may increase the risk of bleeding. • Rate-controlling agents, ...
... • Anti-clotting agents, or anti-coagulants, prevent blood clots that can cause heart attack and stroke. Anti-coagulants are commonly used for patients with atrial fibrillation or mechanical heart valves. Although vital, these medicines may increase the risk of bleeding. • Rate-controlling agents, ...
Personalized management of atrial fibrillation
... of clinical AF management guidelines in the USA (where two updates were published in 201125,26), in Canada (where a new set of guidelines was published in 201227), and in Europe (where a focused update was released in 201228), all with overlapping recommendations.29 Further improvements in managemen ...
... of clinical AF management guidelines in the USA (where two updates were published in 201125,26), in Canada (where a new set of guidelines was published in 201227), and in Europe (where a focused update was released in 201228), all with overlapping recommendations.29 Further improvements in managemen ...
Ventricular Dysrhythmias Learning Outcomes 9.1 Describe the various
... 9.5 Apply Your Knowledge How is an accelerated idioventricular rhythm differ from an idioventricular rhythm? ANSWER: Rate. Accelerated idioventricular rhythm occurs at a rate of 40 to100 beats per minute while an idioventricular rhythm occurs at a rate of 20 to 40 beats per minute. ...
... 9.5 Apply Your Knowledge How is an accelerated idioventricular rhythm differ from an idioventricular rhythm? ANSWER: Rate. Accelerated idioventricular rhythm occurs at a rate of 40 to100 beats per minute while an idioventricular rhythm occurs at a rate of 20 to 40 beats per minute. ...
Atrioventricular N odal Response to Retrograde Activation in Atrial
... . Atrioventricular Nodal Reset. Retrograde (ventriculoatrial) conduction that reaches the atrioventricular node simultaneous with, or just before an atrial impulse can facilitate subsequent anterograde conduction. However, a spontaneous or programmed ventricular extrasystole during atrial fibrillati ...
... . Atrioventricular Nodal Reset. Retrograde (ventriculoatrial) conduction that reaches the atrioventricular node simultaneous with, or just before an atrial impulse can facilitate subsequent anterograde conduction. However, a spontaneous or programmed ventricular extrasystole during atrial fibrillati ...
Cardiac arrhythmias
... their hearts are beating rapidly. Some patients, however, remain unaware of the presence of the arrhythmia, which is particularly the case when the arrhythmia is chronic. The examiner, and the informed patient, can usually detect the characteristic pattern in the pulse or the heart beat. In the neck ...
... their hearts are beating rapidly. Some patients, however, remain unaware of the presence of the arrhythmia, which is particularly the case when the arrhythmia is chronic. The examiner, and the informed patient, can usually detect the characteristic pattern in the pulse or the heart beat. In the neck ...
Relation Between Left Ventricular Diastolic Pressure and Myocardial
... moving the lever arms a. known distance with a double micrometer constructed for this purpose and observing the deflection on the recorder. The calibrating device is shown in figure 2. For calibration, the lever arms were moved in steps of 0.5 mm. and the changes recorded. The sensitivity usually us ...
... moving the lever arms a. known distance with a double micrometer constructed for this purpose and observing the deflection on the recorder. The calibrating device is shown in figure 2. For calibration, the lever arms were moved in steps of 0.5 mm. and the changes recorded. The sensitivity usually us ...
PDF file - Via Medica Journals
... senescence alters the pharmacokinetics of anti-arrhythmic agents making the metabolism less predictable and increasing the predilection for sideeffects, including pro-arrhythmias [8–10]. Degenerative changes in the cardiac conduction system that occur with age predispose the elderly to sick sinus sy ...
... senescence alters the pharmacokinetics of anti-arrhythmic agents making the metabolism less predictable and increasing the predilection for sideeffects, including pro-arrhythmias [8–10]. Degenerative changes in the cardiac conduction system that occur with age predispose the elderly to sick sinus sy ...
the atrial sound and the atrial component of the first - Heart
... In normal subjects inaudible presystolic vibrations can usually be demonstrated in a low frequency phonocardiogram. The relation of these vibrations to pathologically audible atrial sounds and the contribution of atrial action to the formation of the first heart sound are the subject of this paper. ...
... In normal subjects inaudible presystolic vibrations can usually be demonstrated in a low frequency phonocardiogram. The relation of these vibrations to pathologically audible atrial sounds and the contribution of atrial action to the formation of the first heart sound are the subject of this paper. ...
Click here for the printable version of this module.
... Atrial fibrillation represents disorganized atrial activity without contraction or ejection. The electrocardiogram demonstrates an irregular baseline where the normal P waves are replaced with rapidly quivering small deflection of variable amplitude (f waves - outlined below). An irregularly irregul ...
... Atrial fibrillation represents disorganized atrial activity without contraction or ejection. The electrocardiogram demonstrates an irregular baseline where the normal P waves are replaced with rapidly quivering small deflection of variable amplitude (f waves - outlined below). An irregularly irregul ...
Analysis and Interpretation of the Electrocardiogram A Self
... Atrial fibrillation represents disorganized atrial activity without contraction or ejection. The electrocardiogram demonstrates an irregular baseline where the normal P waves are replaced with rapidly quivering small deflection of variable amplitude (f waves - outlined below). An irregularly irregul ...
... Atrial fibrillation represents disorganized atrial activity without contraction or ejection. The electrocardiogram demonstrates an irregular baseline where the normal P waves are replaced with rapidly quivering small deflection of variable amplitude (f waves - outlined below). An irregularly irregul ...
Is Fibrillation Chaos?
... written as a vector of quantities; the set of all such states is called the state space (or phase space). For example, in the case of a simple harmonic oscillator (e.g., a mass on a spring) the state is the instantaneous velocity and position. In a deterministic dynamical system the rule that descri ...
... written as a vector of quantities; the set of all such states is called the state space (or phase space). For example, in the case of a simple harmonic oscillator (e.g., a mass on a spring) the state is the instantaneous velocity and position. In a deterministic dynamical system the rule that descri ...
Cardiology - New England EMS Institute
... Myocardium: middle layer of the heart, unique muscle cells that have the ability to conduct electrical impulses from one muscle cell to another, thus allowing the heart to contract Endocardium: inner layer of heart, ...
... Myocardium: middle layer of the heart, unique muscle cells that have the ability to conduct electrical impulses from one muscle cell to another, thus allowing the heart to contract Endocardium: inner layer of heart, ...
Junctional tachycardias
... They can last a few seconds, several hours, or days. The frequency of episodes can vary between several a day, or one episode in a lifetime. Most patients have only mild symptoms, such as palpitations or the sensation that their heart is beating rapidly. More severe symptoms include dizziness, dyspn ...
... They can last a few seconds, several hours, or days. The frequency of episodes can vary between several a day, or one episode in a lifetime. Most patients have only mild symptoms, such as palpitations or the sensation that their heart is beating rapidly. More severe symptoms include dizziness, dyspn ...
A Rare Heart Rhythm Problem in Acute Rheumatic Fever: Complete
... Rheumatic heart disease remains the most important cause of acquired heart disease in children and young adults [1]. The diagnosis of RF is based on the Jones criteria [2]. Carditis is the most serious manifestation of the rheumatic fever, since it may cause polyarthritis, acute heart failure (panca ...
... Rheumatic heart disease remains the most important cause of acquired heart disease in children and young adults [1]. The diagnosis of RF is based on the Jones criteria [2]. Carditis is the most serious manifestation of the rheumatic fever, since it may cause polyarthritis, acute heart failure (panca ...
Left atrial strain in patients with arterial hypertension
... European Society of Cardiology recommendations 17 who were referred to the Echo Laboratory of Le Scotte Hospital, University of Siena for a diagnostic examination between January 2009 and September 2011. Patients were < 70 years of age, had newly diagnosed, not pharmacologically treated HTN, were in ...
... European Society of Cardiology recommendations 17 who were referred to the Echo Laboratory of Le Scotte Hospital, University of Siena for a diagnostic examination between January 2009 and September 2011. Patients were < 70 years of age, had newly diagnosed, not pharmacologically treated HTN, were in ...
1.5. Electrocardiogr..
... 1. Heart Rate: The heart rate can be estimated by dividing 300 by the number of large squares (5 mm) (example: 5 and ½ large squares - 300/5.5 = 55), or calculated exactly by dividing 1500 by the number of small squares (1 mm) between successive R waves (example: 27 small squares - 1500/27 = 55). No ...
... 1. Heart Rate: The heart rate can be estimated by dividing 300 by the number of large squares (5 mm) (example: 5 and ½ large squares - 300/5.5 = 55), or calculated exactly by dividing 1500 by the number of small squares (1 mm) between successive R waves (example: 27 small squares - 1500/27 = 55). No ...
Atrial fibrillation
Atrial fibrillation (AF or A-fib) is an abnormal heart rhythm characterized by rapid and irregular beating. Often it starts as brief periods of abnormal beating which become longer and possibly constant over time. Most episodes have no symptoms. Occasionally there may be heart palpitations, fainting, shortness of breath, or chest pain. The disease increases the risk of heart failure, dementia, and stroke.Hypertension and valvular heart disease are the most common alterable risk factors for AF. Other heart-related risk factors include heart failure, coronary artery disease, cardiomyopathy, and congenital heart disease. In the developing world valvular heart disease often occurs as a result of rheumatic fever. Lung-related risk factors include COPD, obesity, and sleep apnea. Other factors include excess alcohol intake, diabetes mellitus, and thyrotoxicosis. However, half of cases are not associated with one of these risks. A diagnosis is made by feeling the pulse and may be confirmed using an electrocardiogram (ECG). The typical ECG shows no P waves and an irregular ventricular rate.AF is often treated with medications to slow the heart rate to a near normal range (known as rate control) or to convert the rhythm to normal sinus rhythm (known as rhythm control). Electrical cardioversion can also be used to convert AF to a normal sinus rhythm and is often used emergently if the person is unstable. Ablation may prevent recurrence in some people. Depending on the risk of stroke either aspirin or anti-clotting medications such as warfarin or a novel oral anticoagulant may be recommended. While these medications reduce this risk, they increase rates of major bleeding.Atrial fibrillation is the most common serious abnormal heart rhythm. In Europe and North America, as of 2014, it affects about 2% to 3% of the population. This is an increase from 0.4 to 1% of the population around 2005. In the developing world about 0.6% of males and 0.4% of females are affected. The percentage of people with AF increases with age with 0.14% under 50 years old, 4% between 60 and 70 years old, and 14% over 80 years old being affected. A-fib and atrial flutter resulted in 112,000 deaths in 2013, up from 29,000 in 1990. The first known report of an irregular pulse was by John Baptist Senac in 1749. This was first documented by ECG in 1909 by Thomas Lewis.