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Arrhythmias in the developing heart
Arrhythmias in the developing heart

... atrial flutter, with mostly 2 : 1 AV conduction block, due to excessive atrial frequency in flutter (about 440– 480 bpm) translating into a 220–240 bpm ventricular rate. In AV re-entry, the time interval between the ventricular and atrial activity would be short, while in atrial tachycardia originat ...
Irregularity test for very short electrocardiogram (ECG
Irregularity test for very short electrocardiogram (ECG

... patient. Although the visual inspection of both traces hardly reveals any significant differences between them, the above-outlined method discloses a fascinating fact. In particular, whereas the trace in the upper panel of Fig 2 is characterized by k ⫽ 2.24, the lower recoding has k ⫽ 0.55, which cl ...
Chapter 3 The electrocardiogram
Chapter 3 The electrocardiogram

... the regularity or irregularity of QRS complexes and their association with each P wave. A regular rhythm where each QRS complex is preceded by a P wave (with a normal PR interval) is defined as normal sinus rhythm. If the rhythm is irregular, then this should be further qualified by identifying whet ...
PDF - Circulation: Arrhythmia and Electrophysiology
PDF - Circulation: Arrhythmia and Electrophysiology

... ms (SIR=85 beats per minute) expires in atrial-based timing. However, the presence of 2 consecutive VS events triggers a switch to a ventricular-based timing. In this example, the second consecutive VS event (Figure 2A, asterisk) without a preceding AS or AP event is interpreted as a PVC. As this oc ...
2014 AHA/ACC/HRS Guideline for the€Management of Patients
2014 AHA/ACC/HRS Guideline for the€Management of Patients

... A recommendation with Level of Evidence B or C does not imply that the recommendation is weak. Many important clinical questions addressed in the guidelines do not lend themselves to clinical trials. Although randomized trials are unavailable, there may be a very clear clinical consensus that a part ...
Diastolic Heart Failure:Challenges of Diagnosis and Treatment (Am
Diastolic Heart Failure:Challenges of Diagnosis and Treatment (Am

... a poor prognosis.21 Recent studies also have shown that Doppler evaluation of myocardial velocities during ventricular relaxation predict elevated filling pressure. The E- and A-wave velocities are affected by blood volume and mitral valve anatomy and function. Furthermore, these wave velocities are ...
Regional Mechanical Properties and Microstructure of Ovine Heart
Regional Mechanical Properties and Microstructure of Ovine Heart

... Figure 5.1: Cauchy stress-Green strain data for tissue specimens obtained from the left heart chambers in the fiber and cross fiber directions: (a) left ventricle, (b) left atrium, and (c) left atrial appendage (anterior regions: circle, and posterior regions: asterisk). ........................... ...
Atrial remodeling due to atrial tachycardia and heart failure
Atrial remodeling due to atrial tachycardia and heart failure

... III. ATRIAL REMODELING DUE TO ATRIAL TACHYCARDIA AND FIBRILLATION In recent years, atrial remodeling due to chronic high atrial rates has been the subject of many experimental and clinical studies. It was well known from clinical practice that AF is a progressive arrhythmia in terms of duration and ...
Tachycardia-induced cardiomyopathy in children and
Tachycardia-induced cardiomyopathy in children and

... slow retrograde conduction, also known as a permanent junctional reciprocating tachycardia (PJRT) or Coumel tachycardia. Electrophysiological mapping identified the insertion of the accessory pathway in the right posteroseptal region of the tricuspid annulus near the coronary sinus ostium (Figure 1B ...
PDF - Circulation: Arrhythmia and Electrophysiology
PDF - Circulation: Arrhythmia and Electrophysiology

... In this case, ablation of cavotricuspid isthmus led to change from counterclockwise flutter to clockwise flutter. A closer look at Figure 1 shows that the counterclockwise flutter breaks, and there is one transition beat before the clockwise flutter starts. The last beat of the counterclockwise flut ...
Management of Rhythm and Conduction Disorders
Management of Rhythm and Conduction Disorders

... Atrial flutter: usually rather stable rate Atrial fibrillation: irregular rate Difficult diagnosis if 1:1 or 2:1 conduction Usually poorly tolerated in the immediate postoperative period May co-exist with a sinus node dysfunction (tachycardia-bradycardia syndrome ) ...
Paroxysmal Supraventricular Tachycardia in Patients
Paroxysmal Supraventricular Tachycardia in Patients

... of the Wolff-Parkinson-White syndrome should not be taken as evidence that such an event could not occur. Three months prior to study, case 7, who only demonstrated evidence of pre-excitation with coronary sinus pacing, had an episode of ventricular flutter-fibrillation induced by a bout of atrial f ...
2014 AHA/ACC/HRS Guideline for the€Management of
2014 AHA/ACC/HRS Guideline for the€Management of

... A recommendation with Level of Evidence B or C does not imply that the recommendation is weak. Many important clinical questions addressed in the guidelines do not lend themselves to clinical trials. Although randomized trials are unavailable, there may be a very clear clinical consensus that a part ...
Thesis, Emmanuel Moss 20110625 Final
Thesis, Emmanuel Moss 20110625 Final

... denervation, from 365±252 at baseline to 53±106mm2 following RAGP ablation (p<0.03). With retrograde denervation, chronotropic and repolarisation changes were suppressed following RAGP ablation in two canines, and following Ao/SVC ablation in three. Surface area of REPOL∆ diminished following RAGP a ...
2015 ACC/HRS/SCAI Left Atrial Appendage Occlusion Device
2015 ACC/HRS/SCAI Left Atrial Appendage Occlusion Device

... CHA2DS2-VASc point score (Congestive heart failure, Hypertension, Age ≥75 years [doubled], Diabetes mellitus, Prior Stroke or TIA or thromboembolism [doubled], Vascular disease, Age 65 to74 years, Sex category), which provides an estimate of the potential benefits of therapy (3). The potential risks ...
Beyond the Mitral Inflow - Society of Cardiovascular Anesthesiologists
Beyond the Mitral Inflow - Society of Cardiovascular Anesthesiologists

... A  few  definitions  are  essential  to  understand  the  different  aspects  of  myocardial   mechanics.  Displacement  is  a  parameter  that  defines  the  distance  that  a  certain   feature,  such  as  a  speckle  or  cardiac  struc ...
Morphological features of the P-waves at surface electrocardiogram
Morphological features of the P-waves at surface electrocardiogram

... Bioprosthetic valve implantation Maze-only, n (%) ...
2014 PowerPoint Template Standard
2014 PowerPoint Template Standard

... Do all the QRS complexes look alike? ...
ECG
ECG

...  Sinus tachycardia: SA node paces the heart faster than 100 bpm  Sinus bradycardia: SA node paces the heart slower than 60 bpm  Flutter: 250-350 bpm  Fibrillation: >350 bpm ...
paced - Weebly
paced - Weebly

... A Brief Overview of What It Means To BiV Pace ...
Repolarization Phase at Various Sites of the Right Atrium
Repolarization Phase at Various Sites of the Right Atrium

... experiment and the change in surface temperature was found to be rather small during the experiment (less than ± 0.1°C). It has been known that Qio of the duration of action potential has a value of 2 to 3 in cardiac muscles.21 Therefore, the change in conduction time of depolarization due to a diff ...
Termination and Inhibition of Recurrent Tachyeardias
Termination and Inhibition of Recurrent Tachyeardias

... Wellens13 have utilized the same approach for converting intermittent SVT to NSR in patients without pre-excitation. Both Coumel and Wellens believe that the effectiveness of competitive ventricular pacing in terminating paroxysmal tachycardias is inversely related to the rate of the arrhythmia.10' ...
Junctional rhythm
Junctional rhythm

... cycle of a rhythm initiated by a higher pacemaker when the rate of the dominant pacemaker becomes less than the rate of the AV node. The junction can “escape in” when the electrical impulses of the SA node fail to reach the AV node within 1 to 1½ seconds as in the following: a. ...
Acetylcholine and Electrolyte Metabolism in the Various Chambers
Acetylcholine and Electrolyte Metabolism in the Various Chambers

... space in this tissue. This seems unlikely in view of the data presented in table 5. In these experiments, sinuses and atria were incubated for one hour in an Na deficient medium (28 mMolar). Isotonicity was maintained by the addition of sucrose. Even though incubating the tissues in a low Na medium ...
acc/aha/esc practice guidelines—executive
acc/aha/esc practice guidelines—executive

... or associated cardiovascular pathology. By convention, the term nonvalvular AF is restricted to cases in which the rhythm disturbance occurs in the absence of rheumatic mitral stenosis or a prosthetic heart valve. The classification scheme recommended in this document represents a consensus driven b ...
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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.
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