Effects of Respiratory Center Activity on the Heart
... amplitude of the fluctuations was considerably reduced. An example is displayed in the left half of figure 2. In four experiments after vagotomy, the mean heart rate was 184 min"1 during control conditions (table 1). The amplitude of the heart rate waves was 8.5 min"1, which was significantly less t ...
... amplitude of the fluctuations was considerably reduced. An example is displayed in the left half of figure 2. In four experiments after vagotomy, the mean heart rate was 184 min"1 during control conditions (table 1). The amplitude of the heart rate waves was 8.5 min"1, which was significantly less t ...
Exercise - University Hospitals Bristol NHS Foundation Trust
... their peers. Perhaps this is not surprising for more complex conditions. However, it has been found that even young people with relatively simple, mild conditions often have low levels of fitness. This can prevent them from participating fully in sports and other physical activities. It can also put ...
... their peers. Perhaps this is not surprising for more complex conditions. However, it has been found that even young people with relatively simple, mild conditions often have low levels of fitness. This can prevent them from participating fully in sports and other physical activities. It can also put ...
Structural mechanics of the mosquito heart and its function in
... and air bubbles, demonstrated that the heart is a dynamic organ which alternates between pumping hemolymph in anterograde (toward the head) and retrograde (toward the tip of the abdomen) directions. Quantitative assessment of contraction mechanics showed that the dorsal vessels of unmanipulated 5-da ...
... and air bubbles, demonstrated that the heart is a dynamic organ which alternates between pumping hemolymph in anterograde (toward the head) and retrograde (toward the tip of the abdomen) directions. Quantitative assessment of contraction mechanics showed that the dorsal vessels of unmanipulated 5-da ...
Heart Rate, Stroke Volume and Vasomotor
... case of the aorta, whereas for the two peripheral arteries it was repeatedly established by occlusion of the descending aorta by transient pulling of a snare implanted well above the origin of the superior mesenteric artery. The three flow probes as well as the aortic snare were aseptically implante ...
... case of the aorta, whereas for the two peripheral arteries it was repeatedly established by occlusion of the descending aorta by transient pulling of a snare implanted well above the origin of the superior mesenteric artery. The three flow probes as well as the aortic snare were aseptically implante ...
Paroxysmal supraventricular tachycardia: physiopathology and
... conditions is only manifested by the sinus node and by conduction tissue. It consists in slow, spontaneous diastolic depolarisation until the threshold potential is reached, which conditions the onset of the action potential. Activation frequency decreases from the sinus node, which is the heart’s p ...
... conditions is only manifested by the sinus node and by conduction tissue. It consists in slow, spontaneous diastolic depolarisation until the threshold potential is reached, which conditions the onset of the action potential. Activation frequency decreases from the sinus node, which is the heart’s p ...
Tetralogy of Fallot-Pulmonary Atresia
... May lead to congestive heart failure o As pulmonary vascular resistance (PVR) decreases Pulmonary blood flow may become excessive Results in congestive heart failure o MAPCAs may provide pulmonary blood flow, but are prone to stenosis Require screening for chromosomal anomalies o Common with c ...
... May lead to congestive heart failure o As pulmonary vascular resistance (PVR) decreases Pulmonary blood flow may become excessive Results in congestive heart failure o MAPCAs may provide pulmonary blood flow, but are prone to stenosis Require screening for chromosomal anomalies o Common with c ...
View - OhioLINK Electronic Theses and Dissertations Center
... The progression of HCM is variable with most cats having a long asymptomatic period that may end with the abrupt development of severe congestive heart failure (CHF), arterial thromboembolism (ATE), or sudden cardiac death. Large scale studies involving more than 400 cats with HCM revealed that most ...
... The progression of HCM is variable with most cats having a long asymptomatic period that may end with the abrupt development of severe congestive heart failure (CHF), arterial thromboembolism (ATE), or sudden cardiac death. Large scale studies involving more than 400 cats with HCM revealed that most ...
Pathophysiology and epidemiology of peripartum cardiomyopathy
... secondary to left ventricular systolic dysfunction towards the end of pregnancy or in the months following delivery, where no other cause of heart failure is found. It is a diagnosis of exclusion. The left ventricle may not be dilated but the ejection fraction is nearly always reduced below 45%.”4 P ...
... secondary to left ventricular systolic dysfunction towards the end of pregnancy or in the months following delivery, where no other cause of heart failure is found. It is a diagnosis of exclusion. The left ventricle may not be dilated but the ejection fraction is nearly always reduced below 45%.”4 P ...
Arrhythmia-Induced Cardiomyopathies
... nomic influences and resultant slower rates during sleep are likely to be the reasons that AIC is rare or nonexistent with inappropriate sinus tachycardia and postural orthostatic tachycardia syndrome (POTS), although the average heart rate can be >100 beats/ min. There is no specific heart rate cutof ...
... nomic influences and resultant slower rates during sleep are likely to be the reasons that AIC is rare or nonexistent with inappropriate sinus tachycardia and postural orthostatic tachycardia syndrome (POTS), although the average heart rate can be >100 beats/ min. There is no specific heart rate cutof ...
A cardiovascular-respiratory control system
... are global control mechanisms that act on the entire system to maintain appropriate blood flow and these mechanisms are supplemented by local mechanisms in each vascular region which act to shunt blood to those regions where demand is high and away from areas where demand is low. The overall control ...
... are global control mechanisms that act on the entire system to maintain appropriate blood flow and these mechanisms are supplemented by local mechanisms in each vascular region which act to shunt blood to those regions where demand is high and away from areas where demand is low. The overall control ...
Biomarkers of Heart Failure in Myocarditis and Dilated
... information regarding diagnosis, treatment, identification of individuals at risk for HF, and potentially the pathogenesis of disease. For a biomarker to be clinically useful it should fulfill several criteria: 1) biomarker levels should be able to be accurately assessed using widely available and c ...
... information regarding diagnosis, treatment, identification of individuals at risk for HF, and potentially the pathogenesis of disease. For a biomarker to be clinically useful it should fulfill several criteria: 1) biomarker levels should be able to be accurately assessed using widely available and c ...
Advances in Cardiovascular Imaging
... for reentrant VT, the most frequent arrhythmogenic mechanism in patients with chronic heart disease.14,15 The reentrant wavefront originates from areas of viable myocardium surrounded by fibrous tissue and circulates around scar tissue that forms functional or anatomically fixed conduction block are ...
... for reentrant VT, the most frequent arrhythmogenic mechanism in patients with chronic heart disease.14,15 The reentrant wavefront originates from areas of viable myocardium surrounded by fibrous tissue and circulates around scar tissue that forms functional or anatomically fixed conduction block are ...
Cardiovascular Physiology Of Fish
... performance and survival because it ensures adequate oxygen and nutrient delivery to the tissues, and removes carbon dioxide and other metabolic wastes. Fish cardiovascular morphology/physiology has been an extremely active area of research over the past two decades, and our understanding of this or ...
... performance and survival because it ensures adequate oxygen and nutrient delivery to the tissues, and removes carbon dioxide and other metabolic wastes. Fish cardiovascular morphology/physiology has been an extremely active area of research over the past two decades, and our understanding of this or ...
Cardiac myocytes` dynamic contractile behavior
... Laske and Iaizzo, 2005). Right and left apex has been distinguished by increase of its surface area and relative cell alignment during heart looping (Manasek et al., 1972). Electromechanical coupling demonstrated that increased contraction force following an increase in stimulation frequency was sig ...
... Laske and Iaizzo, 2005). Right and left apex has been distinguished by increase of its surface area and relative cell alignment during heart looping (Manasek et al., 1972). Electromechanical coupling demonstrated that increased contraction force following an increase in stimulation frequency was sig ...
Pacemaker Development in Embryonic Rat Heart Cultured
... somewhat against the iris. The origin of the graft impulse was located by the two electrode technique and confirmed visually. Regardless of the orientation of the tissue when grafted, the area of earliest depolarization was always near the center of the junction between the graft and iris. Mapping o ...
... somewhat against the iris. The origin of the graft impulse was located by the two electrode technique and confirmed visually. Regardless of the orientation of the tissue when grafted, the area of earliest depolarization was always near the center of the junction between the graft and iris. Mapping o ...
Bidirectional Ventricular Septal Defect Shunt: Quantification
... All basic haemodynamic parameters were recorded at rest and at each stage of exercise (BP, heart rate, Oxygen saturation, electrocardiogram). We assessed his shunt in para-sternal long axis window (PLAX). Consultant cardiologist and senior cardiac physiologist carried out the test. We used colour do ...
... All basic haemodynamic parameters were recorded at rest and at each stage of exercise (BP, heart rate, Oxygen saturation, electrocardiogram). We assessed his shunt in para-sternal long axis window (PLAX). Consultant cardiologist and senior cardiac physiologist carried out the test. We used colour do ...
Normal Exercise Capacity in Patients with Severe Left Ventricular
... protocol). All patients had normal pulmonary function at rest and during exercise. Hemodynamics were measured at rest and during supine and upright exercise. The major mechanisms of the preserved exercise capacity in these patients were chronotropic competence, ability to tolerate elevated wedge pre ...
... protocol). All patients had normal pulmonary function at rest and during exercise. Hemodynamics were measured at rest and during supine and upright exercise. The major mechanisms of the preserved exercise capacity in these patients were chronotropic competence, ability to tolerate elevated wedge pre ...
None But The Lethal Heart
... syndrome olwfs horse exhibiting the frame overo pattern none edit on, directed energy weapon wikipedia - a directed energy weapon it had little detectable effect on malleable organs such as the heart a non lethal directed energy weapon developed by the u s, arrhythmia ventricle heart heart - arrhyth ...
... syndrome olwfs horse exhibiting the frame overo pattern none edit on, directed energy weapon wikipedia - a directed energy weapon it had little detectable effect on malleable organs such as the heart a non lethal directed energy weapon developed by the u s, arrhythmia ventricle heart heart - arrhyth ...
Understanding Arrythmias
... This impairs the heart’s ability to efficiently pump blood and increases the risk of developing blood clots which can cause a transient ischemic attack (TIA) or stroke. The electrical signal which causes the heart to beat originates in the SA node - the natural pacemaker of the heart. ...
... This impairs the heart’s ability to efficiently pump blood and increases the risk of developing blood clots which can cause a transient ischemic attack (TIA) or stroke. The electrical signal which causes the heart to beat originates in the SA node - the natural pacemaker of the heart. ...
Comorbidities and Physical and Cognitive Impairments in Elderly
... elderly patients with HF. This variation may be driven in part by the complex relationships and possible interactions between these comorbidities and patient’s various characteristics including age, sex, type of HF, functional status, and cognition 12. The impact of certain comorbidities on outcome ...
... elderly patients with HF. This variation may be driven in part by the complex relationships and possible interactions between these comorbidities and patient’s various characteristics including age, sex, type of HF, functional status, and cognition 12. The impact of certain comorbidities on outcome ...
Fetal heart rate in chromosomally abnormal fetuses
... or ventricular septal defects, valvular abnormalities and either narrowing of the isthmus or truncus arteriosus. Turner syndrome is associated with severe narrowing of the aortic arch. In both trisomy 13 and Turner syndrome, narrowing of the isthmus is accompanied by narrowing of the ascending aorta ...
... or ventricular septal defects, valvular abnormalities and either narrowing of the isthmus or truncus arteriosus. Turner syndrome is associated with severe narrowing of the aortic arch. In both trisomy 13 and Turner syndrome, narrowing of the isthmus is accompanied by narrowing of the ascending aorta ...
The Johns Hopkins Arrhythmia Service A guide for patients and their families
... the United States, the Johns Hopkins Arrhythmia Service rapidly took on a leadership role. An early success was the development and use of the first implantable cardioverter-defibrillator (ICD). In 1980, Dr. Levi Watkins first implanted this device, invented by Drs. Michel Mirowski and Morton Mower, ...
... the United States, the Johns Hopkins Arrhythmia Service rapidly took on a leadership role. An early success was the development and use of the first implantable cardioverter-defibrillator (ICD). In 1980, Dr. Levi Watkins first implanted this device, invented by Drs. Michel Mirowski and Morton Mower, ...
The Principal Title Page
... • In diastolic dysfunction the left ventricle cannot fill up with blood normally due to a hard stiff and non compliant LV and the blood has to be forced in ...
... • In diastolic dysfunction the left ventricle cannot fill up with blood normally due to a hard stiff and non compliant LV and the blood has to be forced in ...
Heart failure
Heart failure (HF), often referred to as congestive heart failure (CHF), occurs when the heart is unable to pump sufficiently to maintain blood flow to meet the body's needs. The terms chronic heart failure (CHF) or congestive cardiac failure (CCF) are often used interchangeably with congestive heart failure. Signs and symptoms commonly include shortness of breath, excessive tiredness, and leg swelling. The shortness of breath is usually worse with exercise, while lying down, and may wake the person at night. A limited ability to exercise is also a common feature.Common causes of heart failure include coronary artery disease including a previous myocardial infarction (heart attack), high blood pressure, atrial fibrillation, valvular heart disease, excess alcohol use, infection, and cardiomyopathy of an unknown cause. These cause heart failure by changing either the structure or the functioning of the heart. There are two main types of heart failure: heart failure due to left ventricular dysfunction and heart failure with normal ejection fraction depending on if the ability of the left ventricle to contract is affected, or the heart's ability to relax. The severity of disease is usually graded by the degree of problems with exercise. Heart failure is not the same as myocardial infarction (in which part of the heart muscle dies) or cardiac arrest (in which blood flow stops altogether). Other diseases that may have symptoms similar to heart failure include obesity, kidney failure, liver problems, anemia and thyroid disease.The condition is diagnosed based on the history of the symptoms and a physical examination with confirmation by echocardiography. Blood tests, electrocardiography, and chest radiography may be useful to determine the underlying cause. Treatment depends on the severity and cause of the disease. In people with chronic stable mild heart failure, treatment commonly consists of lifestyle modifications such as stopping smoking, physical exercise, and dietary changes, as well as medications. In those with heart failure due to left ventricular dysfunction, angiotensin converting enzyme inhibitors or angiotensin receptor blockers along with beta blockers are recommended. For those with severe disease, aldosterone antagonists, or hydralazine plus a nitrate may be used. Diuretics are useful for preventing fluid retention. Sometimes, depending on the cause, an implanted device such as a pacemaker or an implantable cardiac defibrillator may be recommended. In some moderate or severe cases cardiac resynchronization therapy (CRT) may be suggested or cardiac contractility modulation may be of benefit. A ventricular assist device or occasionally a heart transplant may be recommended in those with severe disease despite all other measures.Heart failure is a common, costly, and potentially fatal condition. In developed countries, around 2% of adults have heart failure and in those over the age of 65, this increases to 6–10%. In the year after diagnosis the risk of death is about 35% after which it decreases to below 10% each year. This is similar to the risks with a number of types of cancer. In the United Kingdom the disease is the reason for 5% of emergency hospital admissions. Heart failure has been known since ancient times with the Ebers papyrus commenting on it around 1550 BCE.