…EPS), and the transition from a purely device based management strategy (implantable cardioverter defibrillators) to one that incorporates pharmacological and interventional (substrate ablation) therapies [5] …

…devices. This section is devoted to artificial pacemakers. More advanced devices (ICD, implantable cardioverter defibrillator; CRT, cardiac resynchronization therapy) are discussed in subsequent chapters. The…

…Definition and pathophysiology Cardiac implantable electronic devices (CIEDs) include permanent pacemakers, implantable cardioverter defibrillators (ICDs), and cardiac resynchronization therapy (CRT) devices. Implantable loop recorders are…

…term prediction of sudden cardiac arrest. The constraint does not lie in therapy: implantable cardioverter defibrillators (ICDs) are highly effective, terminating well over 99% of…

…recording and unmask the atrial activity. The investigation is diagnostic, not therapeutic. An unstable patient should be cardioverted, not investigated. Contraindications Haemodynamic instability — hypotension, shock…

…For example, if there is acute ischemia located in the anterior wall and there is ST segment elevation in lead V3, then there should also…

…ischemia. The term transmural ischemia implies that the ischemia affects all wall layers – from endocardium to epicardium – in the myocardium affected by the occlusion. Transmural…

…electrical currents. An ECG lead is a graphical description of the electrical activity of the heart and it is created by analyzing several electrodes. In…

…of cardiac arrest. Recurrent VT or VF after ROSC in a patient with a coronary risk profile should lead to consideration to perform early angiography.

…chest (precordial) electrodes are not changed but additional leads may be attached in children under the age of 5 years. These additional leads are V3R…

…Transcutaneous pacing Equipment A defibrillator with a pacing function and self adhesive multifunction pads. A separate three lead ECG cable connected to the patient — the…

…2. Obtain a 12 lead ECG within 10 minutes. 3. Attach defibrillator pads if the patient is unstable or at marked risk of arrhythmia. 4…

…not exclude dangerous hyperkalaemia. Record a 12 lead ECG and start cardiac monitoring at a plasma potassium above 6.0 mmol/L, and at lower…

…12 lead ECG should be interpreted immediately (within 10 minutes) at first medical contact. I B ECG monitoring should start immediately and a defibrillator must…

…atrial rate (beats/min)? P waves should precede every QRS complex and the P wave should be positive in lead II. Common findings Sinus rhythm …

…positive hyperacute T waves [15]. Profound ST elevation across multiple leads generally indicates very severe ischemia [15]. A key distinguishing feature of ischemic ST elevation…

…usually on a treadmill, while symptoms, a 12 lead ECG, heart rate and blood pressure are monitored. The test is generally symptom limited and is…

…the surface ECG as ST segment displacement. When the ischaemic vector is directed away from the standard anterior leads, posterior infarction may manifest as reciprocal…

…for females) C: Incomplete Right Bundle Branch Block (rSR' pattern in lead V1 and qRS pattern in V6 with QRS duration <120 ms) D: Profound…

…spasm produces a reversible functional occlusion and usually causes transmural ischaemia. The resulting abnormalities in left ventricular function may lead to myocardial infarction, ventricular tachycardia…

…or catheterization laboratory. A 12 lead ECG must be obtained immediately after ROSC in order to identify cases with ST segment elevations, which demand urgent…

…diabetic cardiomyopathy, etc. ) may ultimately lead to ventricular dilation. However, the term dilated cardiomyopathy (DCM) refers to idiopathic or genetic dilation of the left ventricle…

…therefore critical. The 12 lead electrocardiogram (ECG) is an immediately available diagnostic tool that can provide essential clues to LMCA occlusion or critical stenosis. This…

…P waves with constant morphology preceding every QRS complex. P wave is positive in limb lead II. Normal (physiological) causes of sinus bradycardia Sinus bradycardia…

…the impulse from reaching the atria. Disturbed automaticity and blocked impulses lead to arrhythmias that characterize sinus node dysfunction. The conditions encircled by the term…

…evident, ventricular tachycardia may appear more polymorphic in one lead (the upper lead). ECG 2 . Although the signal in the upper lead appears very disorganized…

…pulseless electrical activity (PEA). These are highly lethal arrhythmias that lead to death if cardiopulmonary resuscitation is not started immediately. Ventricular fibrillation is the result…

…P wave precedes every QRS complex; the PR interval is constant and the P wave is positive in lead II. Causes of bradyarrhythmia: sinus bradycardia…

…9 mmol/L, and consider telemetry. The QT interval is measured in the lead in which it is longest, usually II or V5, and the…

…complex. Brugada's algorithm If there is no RS complex in any chest lead (V1–V6) a diagnosis of ventricular tachycardia can be made. Otherwise…

…administration in these patients should be carefully balanced against the potential risks resulting from hypotension. • Withdrawal of clonidine may lead to rebound hypertension. Withdraw slowly…

…ritonavir, and atazanavir) can lead to a significant increase in exposure to ticagrelor. Dosage: Acute Coronary Syndromes Treatment with Ticagrelor should start with a loading…

…male patient (Figure 1) presented at age 36 years with an ECG showing deep and persistent, concave upward ST segment depression in leads I, II…

…Furthermore, because ACE inhibitors also inhibit kininase II, they may lead to the upregulation of bradykinin, which further enhances the effects of angiotensin suppression. In…

…Nevertheless, I recently read Recommendations for interpretation of 12 lead electrocardiogram in the athlete , which is a great paper written by a dozen of merited…

…left hand side). Lead V1 might therefore display a biphasic (diphasic) P wave , meaning that the greater portion of the P wave is positive but…

…causes reciprocal ST segment depressions in V1–V3 (occasionally V4). Leads V7–V9 must be placed to reveal the ST segment elevations. North American (AHA…

…To compute the mean QRS axis, the area under the QRS waveform is measured in at least two leads. Areas above the baseline (typically the…

…Lateral ventricular infarction. Pre excitation. Switched arm electrodes (negative P and QRS T in lead I). Situs inversus. Left posterior fascicular block is diagnosed when…

…Lateral ventricular infarction. Pre excitation. Switched arm electrodes (negative P and QRS T in lead I). Situs inversus. Left posterior fascicular block is diagnosed when…

…but fundamental part of ECG interpretation. The normal T wave in adults is positive in most precordial and limb leads. The T wave amplitude is…

…output is insufficient. Aortic regurgitation may cause myocardial ischemia because cardiac output diminishes in parallel with increasing myocardial load (and hence oxygen demand). The most…

…patients with chest pain. A 12 lead ECG recording must be registered and interpreted within 10 minutes of arrival at the hospital. The ECG differentiates…

…etc. Most cases of malfunction are associated with the electronics in the pulse generator or dislodgement or fracture of the leads. External causes are less…

…However, the term PSVT does not have any clinical relevance and it may lead to misunderstanding. Use of the term PSVT is therefore not recommended…

…implanted pacemakers are dual chamber systems , meaning that two leads are used: one in the atrium and one in the ventricle. Dual chamber systems offer…

…emergency room [ER]). It is recommended that the 12 lead ECG (conventional ECG) be used for interpretation of ischemia. All available ECG criteria for acute…

…the lead tip, and thus generate an action potential that will spread through the myocardium. Components of an artificial pacemaker Pacemakers consist of an implantable…

…early repolarization have varied over the years and across studies. This has lead to much confusion. In 2015 MacFarlane et al issued a consensus statement…

…For instance, administering nitroglycerin to alleviate ischemic chest pain may lead to hemodynamic collapse in patients with right ventricular ischemia or infarction. Recognizing ECG signs…

…be present in at least two anatomically contiguous leads. In patients with STEMI, ST segment elevations and pathological Q waves occur in the same leads…

…valvular disease or congenital heart disease. Cardiomyopathy leads to impaired cardiac function and heart failure. There are six main types of cardiomyopathy: Hypertrophic cardiomyopathy (HCM…

…diminish the QRS amplitudes. Electrical alternans: The amplitude of the QRS complexes vary from one beat to another (in the same lead). This is due…

…for the immune system to reach the bacteria. Endocarditis can lead to the destruction of the valvular apparatus, as well as to embolization in the…

…ischemia. Indeed, it may be so efficient that a total occlusion in the main artery may not lead to infarction due to the collaterals. Occasionally…

…atrial rate (beats/min)? P waves should precede every QRS complex and the P wave should be positive in lead II. Common findings Sinus rhythm …

…stress images to accurately compare corresponding myocardial regions, as misalignment can lead to incorrect interpretation of perfusion differences. Perfusion assessment The assessment of myocardial regions…

…1, upper panel) is typically smooth, symmetric and positive. The P wave in lead II may, however, be slightly asymmetric by having two humps. This…

…large box equals 100 ms at paperspeed 25 mm/s. Figure 2 shows 12 lead ECGs demonstrating right and left bundle branch blocks. Figure 2…

…of ventricular function. Impaired diastolic function (i.e diastolic dysfunction ) may lead to diastolic heart failure (i.e heart failure with preserved ejection fraction, HFPEF …