…myocardial blood flow and measured tracer activity over a wide range (Murthy et al.). As evident in Figure 1, 15 O water is the only…

…7. When the tip reaches the pharynx: let the patient take a mouthful of water and hold it. Advance the electrode at the very moment…

…which spreads through the myocardium like a wavefront in water. Specific ion channels located on the cell membranes open and close during de and repolarization…

…mechanism requires the atria and the ventricles to be activated rapidly and sequentially. Rapid activation is important in order to activate as much myocardium simultaneously…

…and body temperature water for irrigation. Small children need help to keep still. Sedation is usually better than physical restraint — ketamine provides both immobilisation and…

…tap water or sodium chloride 9 mg/mL. The volume matters more than the fluid; irrigate under pressure through a 20 mL syringe and a…

…and convenient activities are more likely to be maintained. For older adults, an achievable programme should incorporate four domains: Aerobic activity Strength training Balance exercises…

Arrhythmias and arrhythmology ECG Ventricular fibrillation, pulseless electrical activity (PEA) and sudden cardiac arrest This chapter will focus on ventricular fibrillation and pulseless electrical activity…

…d and l isomers, which share similar efficacy in prolonging repolarization. However, the l isomer is responsible for virtually all of the beta blocking activity…

…minutes of continuous convulsive activity, t2, the risk of permanent neuronal injury increases. Treatment must therefore start at 5 minutes and be escalated without unnecessary…

…crisis. Mechanism of action Phentolamine is a non selective alpha adrenergic blocker. Phentolamine reduces blood pressure while increasing catecholamine activity. Effects Primarily causes afterload reduction…

…and Pathophysiology Atrial flutter is defined by a macroreentrant atrial circuit, which manifests on the electrocardiogram (ECG) as organized, continuous atrial electrical activity. This activity…

…extends beyond exercise training to incorporate individualized physical activity counselling, risk factor modification, nutritional care, education, psychosocial support, vocational guidance, medical surveillance, and appropriate pharmacological…

…and thereby enhances LDL C removal from plasma. Two principal therapeutic strategies have emerged: Inhibition of circulating PCSK9 activity , using the monoclonal antibodies evolocumab and…

…asystole. The tachyarrhythmias include ventricular fibrillation (VF) and pulseless ventricular tachycardia (VT). The bradyarrhythmias include all bradyarrhythmias, pulse less electrical activity (PEA), and asystole. Bradyarrhythmias…

…insect stings, and drug induced reactions. Approximately 90% of anaphylactic cardiac arrests present with pulseless electrical activity (PEA) as the initial rhythm, while the remainder…

…characterized by short, rapid bursts of atrial activity. In the majority of cases, the arrhythmia is self limiting; however, it may recur and, in some…

…spontaneous cardiac rhythm. The likelihood of achieving spontaneous cardiac activity is a function of the duration of circulatory standstill and the underlying cause, as elaborated…

…the skin and enables the recording of electrical currents. An ECG lead is a graphical description of the electrical activity of the heart and it…

…physical activity and any other precipitating factor. Thresholds The thresholds below are used above all in diabetes. The severity of the symptoms and the patient…

…channel blocker or digitalis, while awaiting the antidote and specific treatment. Bradyasystole during and after cardiac arrest with persisting electrical activity. Overdrive pacing in bradycardia…

…depends on plasma volume and plasma renin activity. Volume depletion and high plasma renin activity increase the effect of enalaprilat, and may cause severe hypotension…

…progress to bradyarrhythmic arrest or pulseless electrical activity (PEA), presenting as cardiovascular collapse and cardiac arrest. Evaluation and Physical Examination The source material does not…

…inflammatory drug that may inhibit inflammasome activity, reduce interleukin 1β and interleukin 6 signalling, lower C reactive protein, and impair neutrophil chemotaxis toward inflammatory…

…sinus baroreceptor activity and acts centrally and peripherally to enhance vagal tone. These sympatho inhibitory effects decrease serum norepinephrine levels, plasma renin levels, and potentially…

…vasodilation. Although primarily defined by these mechanisms, levosimendan also exhibits some type 3 phosphodiesterase inhibitor (PDEI) activity, which may contribute to its inotropic profile. The…

…body weight and haemoglobin A1c Increased uricosuria, with plasma uric acid reduction of approximately 10% to 15% Possible effects on erythropoietin activity and erythropoiesis SGLT2…

…100 containing lipoproteins and exert effects beyond LDL C reduction, including modulation of inflammation, oxidative stress, endothelial function, plaque stability, thrombogenic responses and immune activity…

…required. Potential triggers include thrombus formation and sympathetic activation. Rho kinase may increase vascular smooth muscle sensitivity to calcium by inhibiting myosin phosphatase activity. Patients…

…not sense depolarization outside these boundaries, which may lead to undersensing of true intrinsic activity and thus inappropriate pacemaker activity. As discussed in the previous…

…sum of ventilation, metabolic activity, and perfusion. Increased aerobic metabolism, perfusion, and ventilation result in a higher end tidal carbon dioxide level. Continuous ETCO 2…

…minutes, pulseless electrical activity (PEA) develops. PEA progresses to asystole within minutes, as outlined in the studies by DeBehnke et al. and Safar et al…

…DW, Wickman LL, Swart GL. The hemodynamic and arterial blood gas response to asphyxiation: a canine model of pulseless electrical activity. Resuscitation 1995; 30:16975…

…small to be detected by skin electrodes; the ECG presents the electrical activity of the atrial and ventricular myocardium. Automaticity of pacemaker cells The automaticity…

…The battery is used to deliver pacing pulses, sensing (analyzing electrical activity in the heart) and store electrocardiograms. The pacemaker is powered by a lithium…

…tachyarrhythmia. Except for sinus tachycardia during physical activity, all tachycardias should be considered pathological and the task is to clarify the cause of the tachycardia…

…increased Vagus nerve activity caused by digoxin. Increased Vagus activity diminishes the automaticity in the sinoatrial node (which lowers heart rate) and also slows conduction…

…physical activity. It is based on the subjective physical sensations experienced during exercise, including increased heart rate, increased respiratory rate and depth, increased sweating, and…

…Thus, increased sympathetic activity results in increased heart rate and stronger contractions. Physical exercise increases the venous return to the heart, which results in increased…

…cost of physical activity. One metabolic equivalent (1 MET) is defined as the amount of oxygen consumed while sitting at rest and is equal to…

…with signal intensity comparable to background activity, typically representing infarcted tissue or non viable myocardium. Perfusion patterns and reversibility Perfusion patterns are systematically analyzed by…

…variations in heart rate are due to variations in the activity of the autonomic nervous system and changes in the automaticity of the sinoatrial node…

…Figure 3. Spontaneous atrial activity is sensed by the atrial lead and triggers ventricular stimulations. The QRS complex is wide due to ventricular depolarization proceeding…

…coordinated and efficient atrial and ventricular activity. The conduction system includes the sinoatrial (SA) node, atrioventricular (AV) node, Bundle of His, bundle branches (left and…

…by atrial activity. In endless loop tachycardia, the ventricular impulse manages to propagate to the atria where the atrial electrode records the impulse (and assumes…

…This results in flow heterogeneity and perfusion defects in areas supplied by the disease artery. Thus, vasodilators replicate the effects of exercise on coronary arteries…

…wall motion abnormalities. Figure 1. Standardized myocardial segmentation and nomenclature for echocardiography. The left ventricle is divided into 17 segments for 2D echocardiography. One can…

…during physical activity). Sinus arrest & sinus pause (intermittent failures to discharge impulses). Sinoatrial block (delayed or blocked impulse conduction between the sinoatrial node and the…

…are as follows: Normal (physiologic) sinus tachycardia: The automaticity (rate of spontaneous depolarization) in the sinoatrial node is increased during physical activity, stress, and nervousness…

…shockable rhythm : Cardiac rhythm that cannot be defibrillated or cardioverted. These rhythms include pulse less electrical activity (PEA), asystole, and bradycardia. No Flow : Circulatory standstill…

…Importantly, for the ventricles to have any electrical (and thus pumping) activity at all, an escape rhythm must arise in an ectopic focus (located distal…

…GABA mediated inhibition and increased glutamatergic activity. When the alcohol level suddenly falls, the compensatory excitation remains, producing tremor, sympathetic activation, hallucinations, seizures and delirium …

…blood pressure by inhibiting ACE. Effects • The hypotensive effect of enalaprilat depends on plasma volume and plasma renin activity. Volume depletion and high plasma renin

…and concomitant valvular disease. Risk factor modification, physical activity, dietary and lifestyle measures, high intensity statin therapy, and appropriate antithrombotic treatment form the broader management…

…risk plaques may coexist within one coronary tree, and inflammatory activity may be widespread rather than confined to a single lesion. Plaque composition is heterogeneous…

…Excess mortality becomes apparent approximately 7–10 years after diagnosis and is associated with persistent disease activity, rheumatoid factor and anti cyclic citrullinated peptide antibodies…

…factors, including rest or medication. Time of day and temporal pattern. Change in frequency, severity, or exercise threshold. Potential anginal equivalents include: Dyspnoea on exertion…

…or pulseless electrical activity (PEA). Evaluation and Physical Examination The source material does not provide specific details regarding the physical examination maneuvers for patients with…

…is directed primarily at symptom relief and may not be required in asymptomatic patients. Before drug treatment, recommended or suggested measures include: reassurance; exercise training…

…daily activities, work and independence. Exercise testing can quantify both the time to initial claudication and the maximum tolerated exercise time. Chronic limb threatening ischaemia…