Knowledge base
Every chapter from all eight books, in one list. Filter by book, then by section, or search across every title and summary at once.
222 in total
Basic Cardiac Anatomy & Physiology
Cardiovascular Medicine
- Structural Heart DiseaseHypertension: Causes, investigations, complications & treatmentHypertension is the leading cause of morbidity and mortality worldwide. The individual and public health effects of hypertension are devastating. Due to the…
- Structural Heart DiseaseHeart failure: IntroductionHeart failure is a major public health problem worldwide. While the incidence of coronary heart…
- Structural Heart DiseaseHeart Failure with Reduced Ejection Fraction (HFrEF)Heart failure HF is a complex clinical syndrome characterized by symptoms and signs resulting from structural or functional impairment of ventricular…
- Structural Heart DiseaseHeart Failure with Preserved Ejection Fraction (HFpEF)Heart failure with preserved ejection fraction HFpEF is a complex clinical syndrome characterized by the cardinal symptoms and signs of heart failure HF in…
- Structural Heart DiseaseCoronary Artery DiseaseStable coronary artery disease CAD, frequently referred to as stable angina pectoris, has traditionally been defined and managed as a distinct clinical…
- Structural Heart DiseasePhysiological Assessment of Coronary Stenoses and Revascularization DecisionsAngiographic stenosis severity is a poor surrogate for the hemodynamic significance of a coronary lesion, with anatomic and functional assessment discordant…
- Structural Heart DiseaseST-Elevation Myocardial Infarction (STEMI): Pathophysiology, Diagnosis, and ManagementCoronary atherosclerosis is a chronic, progressive, and highly complex lipid-driven inflammatory disease of the arterial intima that serves as the…
- Structural Heart DiseaseNon-ST Elevation Acute Myocardial Infarction (NSTEMI) and Unstable AnginaCoronary atherosclerosis is a chronic, progressive, and highly dynamic inflammatory disease of the arterial wall. It is characterized by the subendothelial…
- Structural Heart DiseasePulmonary Embolism (PE)Pulmonary embolism occurs when venous thrombi embolize to the pulmonary artery or its branches. In the majority of cases, the thrombus is formed in the deep…
- Structural Heart DiseaseManagement of bradycardia (bradyarrhythmia)https://ekg.nu/amne/bradykardi-behandling-diagnos-bradyarytmi-pacemaker/#Acute bradycardia with hemodynamic effects is a potentially life-threatening…
- Structural Heart DiseaseAnticoagulation Strategies in Atrial FibrillationAtrial fibrillation AF is the most common sustained cardiac arrhythmia and a profound driver of global cardiovascular morbidity and mortality, primarily due…
- Structural Heart DiseaseBrugada Syndrome: Diagnosis & SCD PreventionSince its initial description in 1992 as a syndrome of right bundle branch block, ST-segment elevation, and sudden cardiac death SCD, Brugada syndrome BrS…
- Structural Heart DiseaseVentricular TachycardiaVentricular tachycardia VT represents a complex and potentially lethal spectrum of cardiac arrhythmias that remains a formidable challenge in contemporary…
- Drug ManualsAntiarrhythmic drugs in ventricular tachyarrhythmiasThis manual presents recommendations for the management of ventricular tachyarrhythmias VT, VF. It is primarily intended for use in an emergency setting.…
- Drug ManualsInotropes and Vasopressors: Doses, indications, contraindications and effectsVasopressors induce vasoconstriction and increase mean arterial pressure MAP. Inotropes increase cardiac contractile force contractility. Several endogenous…
- Drug ManualsLevosimendan (Simdax, Simendan) in acute heart failureLevosimendan exhibits both inotropic and vasodilatory effects. The drug exerts its effects through three pharmacological mechanisms: 1 augmentation of…
- Drug ManualsHypertensive emergency (crisis)This drug manual is provided for use in patients with hypertensive emergency also referred to as hypertensive crisis or malignant hypertension. Hypertensive…
- Drug ManualsAdenosine for tachyarrhythmias (AVNRT, AVRT, NCT)Substance: Adenosine
- Myocardial perfusion imaging (SPECT, PET)Principles of myocardial perfusion imaging (SPECT, PET), coronary blood flow and flow reserve (CFR)Myocardial perfusion imaging MPI is a non-invasive technique for detecting and quantifying coronary artery disease CAD. It offers visual and numerical…
- Myocardial perfusion imaging (SPECT, PET)Indications and contraindications for myocardial perfusion imaging2. Diagnosis of coronary artery disease CAD: Myocardial perfusion imaging can confirm or rule out CAD in patients with symptoms suggestive of CAD.
- Myocardial perfusion imaging (SPECT, PET)The ischemic cascadeThe ischemic cascade describes the sequence of events during myocardial ischemia, beginning with perfusion abnormalities and ultimately leading to chest…
- Myocardial perfusion imaging (SPECT, PET)Physics of myocardial perfusion imaging (SPECT, PET): Radiotracers, perfusion, blood flow and viabilityQuantitative PET perfusion imaging offers precise measurements of myocardial blood flow in milliliters per minute per gram of tissue mL/min/g. This…
- Myocardial perfusion imaging (SPECT, PET)Pharmacologic agents in myocardial perfusion imagingPharmacologic stress tests are indicated in the following scenarios:
- Myocardial perfusion imaging (SPECT, PET)Interpretation of myocardial perfusion images (Myocardial SPECT / PET)Interpreting myocardial perfusion SPECT images involves a systematic comparison of rest and stress images to assess myocardial ischemia and infarction. The…
Clinical ECG Interpretation
- Introduction to ECG InterpretationCardiac electrophysiology and ECG interpretationTo ensure effective cardiac pumping function, the atria and the ventricles must be activated rapidly and sequentially. Rapid activation is important in…
- Introduction to ECG InterpretationCardiac electrophysiology: Action potential, automaticity and vectorsThe following video lecture summarises this chapter.
- Introduction to ECG InterpretationThe ECG leads: Electrodes, limb leads, chest (precordial) leads and the 12-Lead ECGBefore discussing the ECG leads and various lead systems, we need to clarify the difference between ECG leads and ECG electrodes. An electrode is a…
- Introduction to ECG InterpretationThe Cabrera format of the 12-lead ECG and inverted lead aVRNumerous conditions that can be diagnosed using the 12-lead ECG require that ECG changes occur in two or more anatomically contiguous leads, which implies…
- Introduction to ECG InterpretationECG interpretation: Characteristics of the normal ECG (P-wave, QRS complex, ST segment, T-wave)This is arguably one of the most important chapters throughout this course. At the heart of ECG interpretation lies the ability to determine whether the ECG…
- Introduction to ECG InterpretationHow to interpret the ECG: A systematic approachThe ECG must always be interpreted systematically. Failure to perform a systematic interpretation of the ECG may be detrimental. The interpretation…
- Arrhythmias and arrhythmologyMechanisms of cardiac arrhythmias: from automaticity to re-entry (reentry)This section introduces the most common arrhythmias encountered in clinical practice, beginning with a discussion of the underlying mechanisms of cardiac…
- Arrhythmias and arrhythmologyAberrant ventricular conduction (aberrancy, aberration)Aberrant conduction is not a mechanism of arrhythmia; it is a ventricular conduction disturbance. It is discussed in this chapter because the phenomenon is…
- Arrhythmias and arrhythmologyPremature ventricular contractions (premature ventricular complex, premature ventricular beats)Premature ventricular complexes are also referred to as premature ventricular beats, premature ventricular contractions or just ventricular…
- Arrhythmias and arrhythmologyPremature atrial contraction (premature atrial beat / complex): ECG and clinical implicationsA premature atrial contraction is produced by an impulse discharged from an ectopic focus located anywhere in the atria. In most cases, the premature atrial…
- Arrhythmias and arrhythmologySinus rhythm: physiology, ECG criteria & clinical implicationsA rhythm is defined as three consecutive heartbeats with identical waveforms on the ECG. The similarity of the waveforms indicates that the origin of the…
- Arrhythmias and arrhythmologySinus arrhythmia (respiratory sinus arrhythmia)Sinus arrhythmia and respiratory sinus arrhythmia both refer to the same phenomenon. Sinus arrhythmia fulfill all criteria for sinus rhythm except from the…
- Arrhythmias and arrhythmologySinus bradycardia: definitions, ECG, causes and managementSinus bradycardia fulfills the criteria for sinus rhythm but the heart rate is slower than 50 beats per minute. ECG criteria follow:
- Arrhythmias and arrhythmologyChronotropic incompetence (inability to increase heart rate)Chronotropic incompetence is an independent predictor of overall and cardiovascular mortality. The condition is very common among individuals with heart…
- Arrhythmias and arrhythmologySinoatrial arrest & sinoatrial pause (sinus pause / arrest)A sinoatrial arrest occurs when the sinoatrial node does not discharge an impulse for ≥2 seconds. Failure to discharge an impulse within <2 seconds is…
- Arrhythmias and arrhythmologySinoatrial block (SA block): ECG criteria, causes and clinical featuresSinoatrial SA block implies that the impulses discharged in the sinoatrial node are either not conducted to the atria or are so with a delay. This manifests…
- Arrhythmias and arrhythmologySinus node dysfunction (SND) and sick sinus syndrome (SSS)Sinus node dysfunction is an umbrella term for conditions that either affect the automaticity of the sinoatrial node or block the impulse from reaching the…
- Arrhythmias and arrhythmologySinus tachycardia & Inappropriate sinus tachycardiaSinus tachycardia is the most common tachyarrhythmia tachycardia. Sinus tachycardia is the result of an increased rate of depolarization i.e increased…
- Arrhythmias and arrhythmologyAtrial fibrillation: ECG, classification, causes, risk factors & managementAtrial fibrillation is the most common abnormal tachyarrhythmia only sinus tachycardia is…
- Arrhythmias and arrhythmologyAtrial flutter: classification, causes, ECG criteria and managementAtrial flutter is the second most common pathological tachyarrhythmia. Only atrial fibrillation is more common.…
- Arrhythmias and arrhythmologyEctopic atrial rhythm (EAT), atrial tachycardia (AT) & multifocal atrial tachycardia (MAT)Ectopic atrial tachycardia EAT, or atrial tachycardia arises when an ectopic focus within the atria generates electrical impulses at a rate exceeding that…
- Arrhythmias and arrhythmologyAtrioventricular nodal reentry tachycardia (AVNRT): ECG features & managementAtrioventricular nodal reentrant tachycardia AVNRT is a common tachyarrhythmia observed across all age groups, from children to the elderly, and frequently…
- Arrhythmias and arrhythmologyPre-excitation, Atrioventricular Reentrant (Reentry) Tachycardia (AVRT), Wolff-Parkinson-White (WPW) syndromeThe atrioventricular node and bundle of His are normally the only communication between the atria and the ventricles. The atrial impulse must pass through…
- Arrhythmias and arrhythmologyJunctional rhythm (escape rhythm) and junctional tachycardiaIn this article, you will learn about rhythms arising in, or near, the atrioventricular AV node. The most common rhythm arising in the AV node is…
- Arrhythmias and arrhythmologyVentricular rhythm and accelerated ventricular rhythm (idioventricular rhythm)This article provides an overview of ventricular rhythm and accelerated ventricular rhythm, the latter also known as idioventricular rhythm. Recognizing…
- Arrhythmias and arrhythmologyVentricular tachycardia (VT): ECG criteria, causes, classification, treatmentThis chapter deals with ventricular tachycardia from a clinical perspective, with emphasis on ECG diagnosis, definitions, management, and clinical…
- Arrhythmias and arrhythmologyLong QT (QTc) interval, long QT syndrome (LQTS) & torsades de pointesThe QT interval is the time interval from the beginning of the QRS complex to the end of the T-wave. This interval represents the total time taken to…
- Arrhythmias and arrhythmologyVentricular fibrillation, pulseless electrical activity and sudden cardiac arrestThis chapter will focus on ventricular fibrillation and pulseless electrical activity PEA. These are highly lethal arrhythmias that lead to death if…
- Arrhythmias and arrhythmologyPacemaker-mediated tachycardia (PMT): ECG and managementPacemaker-mediated tachycardia may arise if the pacemaker records a rapid atrial rate e.g. during a supraventricular tachycardia and stimulates the…
- Arrhythmias and arrhythmologyDiagnosis and management of supraventricular and ventricular tachyarrhythmias: Narrow complex tachycardia & wide complex tachycardiaAll clinically significant supraventricular and ventricular tachyarrhythmias have been reviewed in previous sections. However, given that each arrhythmia…
- Myocardial Ischemia & InfarctionIntroduction to Coronary Artery Disease (Ischemic Heart Disease)Coronary artery disease, which is synonymous with ischemic heart disease, is the most common form of cardiovascular disease. It has been the number one…
- Myocardial Ischemia & InfarctionClassification of Acute Coronary Syndromes (ACS) & Acute Myocardial Infarction (AMI)Acute coronary syndromes occur when atherosclerotic plaques disrupt, resulting in the activation of thrombocytes and coagulation factors causing the…
- Myocardial Ischemia & InfarctionA New Approach to Acute Coronary Syndromes: Occlusion MI (OMI) vs. Non-Occlusion MI (NOMI)The traditional classification of acute coronary syndromes ACS into ST-segment elevation myocardial infarction STEMI, non-STEMI NSTEMI, and unstable angina…
- Myocardial Ischemia & InfarctionClinical application of ECG in chest pain & acute myocardial infarctionAn ECG must be performed on all patients seeking medical attention due to chest discomfort or other symptoms that may be caused by myocardial ischemia.…
- Myocardial Ischemia & InfarctionDiagnostic Criteria for Acute Myocardial Infarction: Cardiac troponins, ECG & SymptomsAcute myocardial infarction is the most severe complication of coronary artery disease. The most common initiating mechanism is rupture or erosion of a…
- Myocardial Ischemia & InfarctionCardiac troponin I (TnI) and T (TnT): Interpretation and evaluation in acute coronary syndromesTroponin is a protein complex expressed in cardiac and skeletal muscle. The complex consists of troponin I TnI, troponin C TnC and troponin T TnT, which…
- Myocardial Ischemia & InfarctionMyocardial Ischemia & infarction: Cellular changes, ECG and symptomsLike all other cells in the human body, cardiac myocytes use ATP adenosine triphosphate as the primary energy source. ATP is produced by metabolizing…
- Myocardial Ischemia & InfarctionThe left ventricle in myocardial ischemia and infarctionMyocardial infarction is virtually synonymous with left ventricular infarction. All myocardial infarctions affect the left ventricle. Right ventricular…
- Myocardial Ischemia & InfarctionFactors that modify the natural course in acute myocardial infarction (AMI)The traditional distinction between NSTE-ACS NSTEMI,…
- Myocardial Ischemia & InfarctionECG in myocardial ischemia: ischemic changes in the ST segment & T-waveThis chapter discusses typical and atypical changes in the ST segment and the T-wave during myocardial ischemia. A thorough discussion of the…
- Myocardial Ischemia & InfarctionST segment depression in myocardial ischemia and differential diagnosesST segment depressions caused by ischemia are characterized by a horizontal or downsloping ST segment. Indeed, North American and European guidelines assert…
- Myocardial Ischemia & InfarctionST segment elevation in acute myocardial ischemia and differential diagnosesST segment elevations with straight horizontal, upsloping, or downsloping or convex ST segment strongly suggest acute transmural ischemia Figure 1 A.…
- Myocardial Ischemia & InfarctionST elevation myocardial infarction (STEMI) without ST elevations on 12-lead ECGThis chapter covers situations in which the 12-lead ECG does not exhibit ST…
- Myocardial Ischemia & InfarctionT-waves in ischemia: hyperacute, inverted (negative), Wellen's sign & de Winter's signA thorough discussion regarding the physiology of the T-wave was previously provided. Only aspects…
- Myocardial Ischemia & InfarctionECG manifestations of left main coronary artery (LMCA) occlusion and critical stenosisLeft main coronary artery LMCA occlusion is a rare but catastrophic manifestation of acute coronary syndromes. The LMCA supplies a large myocardial…
- Myocardial Ischemia & InfarctionECG signs of myocardial infarction: pathological Q-waves & pathological R-wavesMyocardial infarction – particularly if extensive in size – typically manifests with pathological Q-waves. These Q-waves are wider and deeper than normally…
- Myocardial Ischemia & InfarctionOther ECG changes in ischemia and infarctionNormal R-wave progression implies that the R-wave amplitude increases gradually from V1 to V5 and then diminishes again in V6. Refer to Figure 1. Abnormal…
- Myocardial Ischemia & InfarctionSupraventricular and intraventricular conduction defects in myocardial ischemia and infarctionBradycardia and conduction defects, such as bundle branch block, fascicular block and AV block, are common in myocardial ischemia and infarction. These…
- Myocardial Ischemia & InfarctionECG localization of myocardial infarction / ischemia and coronary artery occlusion (culprit)Determining the localization of myocardial infarction and ischemia, as well as identifying the occluded coronary artery and the location of the occlusion,…
- Myocardial Ischemia & InfarctionThe ECG in assessment of myocardial reperfusionThe ECG is an invaluable tool to assess whether an occlusion has been resolved and blood flow has been restored. This assessment is performed daily in the…
- Myocardial Ischemia & InfarctionApproach to patients with chest pain: differential diagnoses, management & ECGChest pain is one of the most common symptoms in the emergency department, as well as in primary health care. The cause etiology of chest pain varies…
- Myocardial Ischemia & InfarctionStable Coronary Artery Disease (Angina Pectoris): Diagnosis, Evaluation, ManagementStable coronary artery disease CAD, frequently referred to as stable angina pectoris, has traditionally been defined and managed as a distinct clinical…
- Myocardial Ischemia & InfarctionNSTEMI (Non-ST Elevation Myocardial Infarction) & Unstable Angina: Diagnosis, Criteria, ECG, Management!/img/2024/07/antithrombotic-regimens-in-patients-with-acute-coronary-syndromes-stemi-nstemi-ua-and-an-indication-for-oral-anticoagulation-1024x569.webphttps:…
- Myocardial Ischemia & InfarctionSTEMI (ST Elevation Myocardial Infarction): Diagnosis, ECG, Criteria, and ManagementAcute ST Elevation Myocardial Infarction STEMI is the most severe manifestation of coronary artery disease. This chapter deals with the pathophysiology,…
- Conduction DefectsOverview of atrioventricular (AV) blocksThis article covers the fundamental principles of atrioventricular AV blocks, which are classified into three types: first-degree, second-degree, and…
- Conduction DefectsFirst-degree AV block (AV block I, AV block 1)This chapter discusses first-degree atrioventricular AV block, also referred to as 1st-degree AV block, AV block I, or AV block 1. Before proceeding, it is…
- Conduction DefectsSecond-degree AV block: Mobitz type 1 (Wenckebach) & Mobitz type 2 blockIn this chapter, the focus will be on second-degree atrioventricular AV block. Before proceeding, it is advised to review the introductory chapter on AV…
- Conduction DefectsThird-degree AV block (3rd degree AV block, AV block 3, AV block III)This chapter discusses third-degree AV block, which is synonymous with AV dissociation, complete AV block, AV block III and AV block 3. In third-degree AV…
- Conduction DefectsManagement and treatment of AV block (atrioventricular blocks)Evaluation of patients with suspected AV blocks requires a thorough medical history with emphasis on causes of AV blocks; please refer to the Causes of AV…
- Conduction DefectsIntraventricular conduction delay: bundle branch blocks & fascicular blocksThis chapter discusses intraventricular conduction delays defects, which are caused by functional or anatomical defects in the components of the…
- Conduction DefectsRight bundle branch block (RBBB): ECG, criteria, definitions, causes & treatmentRight bundle branch block RBBB is due to an anatomical or functional dysfunction in the right bundle branch, such that the electrical impulse is blocked.…
- Conduction DefectsLeft bundle branch block (LBBB): ECG criteria, causes, managementLeft bundle branch block LBBB results from anatomical or functional impairment of the left bundle branch LBB, leading to a blockage of electrical impulse…
- Conduction DefectsLeft bundle branch block (LBBB) in acute myocardial infarction: the Sgarbossa criteriaContrary to right bundle branch block, left bundle branch block is always a pathological finding that affects cardiovascular and total mortality. Left…
- Conduction DefectsFascicular block (hemiblock): Left anterior & left posterior fascicular blockFascicular blocks were previously referred to as hemiblocks, but the latter term has been deprecated. The left bundle branch is subdivided into the…
- Conduction DefectsNonspecific intraventricular conduction delay (defect)A nonspecific intraventricular conduction delay exists if the ECG displays a widened QRS appearance that is neither a left bundle branch block…
- Cardiac Hypertrophy & EnlargementAtrial and ventricular enlargement: hypertrophy and dilatation on ECGCardiac chamber enlargement refers to abnormally large atria or abnormally large ventricles. These conditions are referred to as atrial enlargement and…
- Cardiac Hypertrophy & EnlargementECG in left ventricular hypertrophy (LVH): criteria and implicationsThe following figure shows characteristic ECG changes in left ventricular hypertrophy LVH and right ventricular hypertrophy…
- Cardiac Hypertrophy & EnlargementRight ventricular hypertrophy (RVH): ECG criteria & clinical characteristicsFigure 1. ECG changes seen in left ventricular hypertrophy LVH and right ventricular hypertrophy RVH. The electrical vector of the left ventricle is…
- Cardiac Hypertrophy & EnlargementBiventricular hypertrophy ECG and clinical characteristicsSimultaneous hypertrophy of the left and right ventricle is rather common. The…
- Cardiac Hypertrophy & EnlargementLeft atrial enlargement (P mitrale) & right atrial enlargement (P pulmonale) on ECGThe atria may become dilated and/or hypertrophic during pathological circumstances. As for ventricular enlargement, the…
- Drugs & Electrolyte ImbalanceDigoxin - ECG changes, arrhythmias, conduction defects & treatmentDigoxin may be used in patients with heart failure, atrial fibrillation, atrial flutter, and in selected cases of paroxysmal supraventricular tachycardia.…
- Drugs & Electrolyte ImbalanceECG changes caused by antiarrhythmic drugs, beta blockers & calcium channel blockersAlthough the purpose of antiarrhythmic drugs is to control arrhythmias, these medications may also cause arrhythmias and confusing ECG changes. ECG changes…
- Drugs & Electrolyte ImbalanceECG changes due to electrolyte imbalance (disorder)The normal cardiac action potential may be altered by electrolyte imbalance, owing to changes in intra- and extracellular electrolyte concentrations. Some…
- Genetics, Syndromes & MiscellaneousECG J wave syndromes: hypothermia, early repolarization, hypercalcemia & Brugada syndromeThe J wave – also referred to as Osborn's wave – is defined as a wave occurring at the J point Figure 1. Conditions in which the J wave occurs may be…
- Genetics, Syndromes & MiscellaneousBrugada syndrome: ECG, clinical features and managementPedro Brugada and his two brothers, Josep and Ramon, described this syndrome in 1992. The syndrome is characterized by a rather peculiar…
- Genetics, Syndromes & MiscellaneousEarly repolarization pattern on ECG (early repolarization syndrome)Although the early repolarization pattern has been recognized for almost 50 years, it is still one of the most frequently confused ECG findings. This is…
- Genetics, Syndromes & MiscellaneousTakotsubo cardiomyopathy (broken heart syndrome, stress induced cardiomyopathy)Takotsubo cardiomyopathy broken heart syndrome is a rather peculiar and certainly acute condition. Much research has been devoted to it in recent years.…
- Genetics, Syndromes & MiscellaneousPericarditis, myocarditis & perimyocarditis: ECG, criteria & treatmentThe pericardium is a double-walled sac in which the heart and the roots of the great vessels are contained Figure 1. The pericardial sac encloses the…
- Genetics, Syndromes & MiscellaneousEletrical alternans: the ECG in pericardial effusion & cardiac tamponadeThe pericardial space cavity always contains a small amount of serous fluid which acts as a lubricant that prevents friction during ventricular contraction…
- Genetics, Syndromes & MiscellaneousLong QT Syndrome (LQTS)Please refer to the previous chapter: LQTS Long QT Syndrome
- Exercise Stress Testing (Exercise ECG)Introduction to exercise stress testing (treadmill test, exercise ECG)Exercise stress testing has been used routinely for over 60 years to evaluate cardiopulmonary function and to diagnose cardiovascular disease. The value of…
- Exercise Stress Testing (Exercise ECG)Indications, Contraindications, and Preparations for Exercise Stress TestingIn this article, we will discuss indications, contraindications, and subject preparations. We will also discuss the relevance of withholding specific…
- Exercise Stress Testing (Exercise ECG)Exercise stress test (exercise ECG): protocols, evaluation & terminationThe choice of exercise equipment and protocol depends mainly on local traditions. The treadmill and cycle ergometer bicycle are the most frequently used…
- Exercise Stress Testing (Exercise ECG)Exercise stress testing in special patient populationsClinicians should be familiar with the special challenges posed by some patient populations. The sensitivity, specificity, risks, and results of the…
- Exercise Stress Testing (Exercise ECG)Exercise physiology: from normal response to myocardial ischemia & chest painUnderstanding the basic principles of exercise physiology is essential to conduct and evaluate the exercise stress test. Exercise induces physiological…
- Exercise Stress Testing (Exercise ECG)Evaluation of exercise stress test: ECG, symptoms, blood pressure, heart rate, performanceThe ECG reaction has always been a central component of the exercise stress test. Indeed, clinicians often use the term exercise ECG instead of the correct…
Clinical Echocardiography
- Introduction to echocardiography and ultrasound imagingPhysics of ultrasoundUnlike light waves, which can propagate through vacuum, sound waves can only propagate through a physical medium. This medium may consist of any matter, e.g…
- Introduction to echocardiography and ultrasound imagingThe ultrasound transducerThe ultrasound transducer generates ultrasound ultrasonic waves The transducer is held with one hand and…
- Introduction to echocardiography and ultrasound imagingTechnical aspects of the ultrasound imageThe ultrasound transducer generates short bursts pulses of ultrasound waves. Reflected…
- Introduction to echocardiography and ultrasound imagingTwo-dimensional (2D) echocardiographyTwo-dimensional 2D ultrasound is the most commonly used modality in echocardiography. The two dimensions presented are width x axis and depth y axis. The…
- Introduction to echocardiography and ultrasound imagingOptimization of the ultrasound imageIn order to obtain optimal ultrasound images, it is necessary to adjust several parameters continuously during the examination. Typically, examinations in…
- Introduction to echocardiography and ultrasound imagingM-mode (motion mode) echocardiographyM-mode was previously the dominating modality in echocardiography. Although it has now largely been replaced by 2D…
- Introduction to echocardiography and ultrasound imagingDoppler effect and Doppler echocardiographyWhen sound waves hit objects some of the sound waves are reflected back to the sound source. If the reflector i.e the object reflecting the sound waves is…
- Introduction to echocardiography and ultrasound imagingPulsed Wave DopplerThe pulsed wave Doppler PW Doppler sends short pulses of ultrasound and analyzes reflected sound waves between the pulses. This is accomplished by using the…
- Introduction to echocardiography and ultrasound imagingContinuous Wave Doppler (CW Doppler)In continuous wave Doppler CW Doppler, ultrasound waves are continuously emitted from the transducer and the reflections of these waves are analyzed…
- Introduction to echocardiography and ultrasound imagingColor DopplerVelocities recorded in a sample volume of the pulsed wave Doppler can be presented with a color. A color scale…
- Introduction to echocardiography and ultrasound imagingTissue Doppler (Tissue Velocity Imaging)Previous chapters on Doppler imaging have all focused on measurements of blood flow. However, the Doppler…
- Introduction to echocardiography and ultrasound imagingArtifacts in ultrasound imagingThe following artifacts are common in ultrasound imaging:
- Principles of hemodynamicsHemodynamic principles and calculationsHemodynamics is the study of blood flow dynamics. The physical laws that govern blood flow are fundamental in echocardiography. Conventional two-dimensional…
- Principles of hemodynamicsThe Bernoulli principle and estimation of pressure gradientsContinuous wave Doppler and pulsed wave…
- Principles of hemodynamicsThe Continuity Equation (The Principle of Continuity)As previously discussed, stroke volume is usually calculated by…
- Principles of hemodynamicsProximal Isovelocity Surface Area (PISA)PISA Proximal Isovelocity Surface Area is a phenomenon that occurs when liquid flows through a circular orifice. The flow will converge and accelerate just…
- Principles of hemodynamicsStroke Volume, VTI (Velocity Time Integral) & Cardiac OutputIf the flow in a cylinder is constant, then flow Q is the product of the cylinder area a and flow velocity v:
- The echocardiographic examinationPrinciples and Preparations for Echocardiographic ExaminationsThe use of echocardiography has increased dramatically during the past few decades. Advances in echocardiography have been propelled by breakthroughs in…
- The echocardiographic examinationPerforming Echocardiographic ExaminationsIn small children, it is possible to perform the entire transthoracic echocardiography…
- The echocardiographic examinationStandard Transthoracic Echocardiogram: Complete Imaging ProtocolThis chapter presents a sequential series of images that comprise a complete standard echocardiographic examination. The image views are discussed in the…
- Left ventricular systolic function and contractilityLeft Ventricular FunctionCardiac function depends on a large number of parameters, including atrial function, valvular function, and ventricular function. A large body of science…
- Left ventricular systolic function and contractilityMyocardial Mechanics: Structure and Function of Myocardial FibersThe left ventricular wall can be subdivided into several layers. These layers are similar to those seen in arteries throughout the circulatory system Figure…
- Left ventricular systolic function and contractilityVentricular Pressure-Volume Relationship: Preload, Afterload, Stroke Volume, Wall Stress & Frank-Starling's lawLeft ventricular pressure-volume relationship can be described by a loop diagram with volume depicted on the x-axis and left ventricular pressure on the…
- Left ventricular systolic function and contractilityAssessing left ventricular systolic functionSeveral echocardiographic measurements are available to assess left ventricular systolic function. These methods elucidate slightly different aspects of…
- Left ventricular systolic function and contractilityLeft ventricular mass and volume (size)Left ventricular mass is a flawed proxy for ventricular systolic function and load. The mass is, however, an important parameter in the assessment of…
- Left ventricular systolic function and contractilityEjection fraction (EF): Physiology, Measurement & Clinical EvaluationFor several decades, ejection fraction EF has been the dominating method for assessing left ventricular systolic function. Ejection fraction is simple to…
- Left ventricular systolic function and contractilityFractional shortening for estimation of ejection fractionFractional shortening FS is calculated by measuring the percentage change in left ventricular diameter during systole. It is measured in parasternal long…
- Left ventricular systolic function and contractilityStrain, strain rate and speckle tracking: Myocardial deformationAs previously discussed, the left ventricular wall can be subdivided into three layers: the inner lining endocardium, a thick muscle layer myocardium and an…
- Left ventricular systolic function and contractilityLeft Ventricular Segments for Echocardiography and Cardiac ImagingCardiovascular imaging modalities have developed rapidly in the past few decades. The repertoire of available methods includes echocardiography,…
- Left ventricular systolic function and contractilityThe Coronary ArteriesThe two main coronary arteries emanate from the aortic bulb Figure 1:
- Left ventricular systolic function and contractilityRegional Myocardial Contractile Function: Wall Motion AbnormalitiesSystolic ventricular function is one of the strongest predictors of total and cardiovascular mortality. Previous chapters have discussed several methods for…
- Left ventricular diastolic functionLeft ventricular diastolic functionThe importance of systolic function can be understood on an…
- Left ventricular diastolic functionRelaxation of the left ventricleDiastolic function is determined by the efficiency of myocardial relaxation. The degree and velocity of relaxation are the key parameters. Ideally,…
- Left ventricular diastolic functionAssessment of diastolic function by echocardiographyMethods for evaluating left ventricular diastolic function have evolved considerably in the past two decades. Currently recommended methods evaluate left…
- CardiomyopathiesHeart failure: Causes, types, diagnosis, treatments & managementHeart failure is a major public health problem worldwide. While the incidence of coronary heart…
- CardiomyopathiesEchocardiography in cardiomyopathies: an overviewCardiomyopathy implies that the myocardium is structurally and functionally altered, and the pathological changes are not explained by coronary heart…
- CardiomyopathiesHypertrophic Cardiomyopathy (HCM) & Hypertrophic Obstructive Cardiomyopathy (HOCM)Hypertrophic cardiomyopathy is a genetic disorder that causes left ventricular hypertrophy under normal loading conditions. Hypertrophic cardiomyopathy…
- CardiomyopathiesDilated Cardiomyopathy (DCM): Definition, Types, Diagnostics & TreatmentDilated cardiomyopathy DCM is defined as dilation of one or both ventricles. Dilation of the left ventricle is virtually always accompanied by impaired left…
- CardiomyopathiesArrhythmogenic Right Ventricular Cardiomyopathy / Dysplasia (ARVC, ARVD)Arrhythmogenic Right Ventricular Cardiomyopathy ARVC is considered a genetic cardiomyopathy that predominantly affects the right ventricle. ARVC is defined…
- CardiomyopathiesTachycardia induced cardiomyopathyA prolonged tachycardia can cause cardiomyopathy with left ventricular dilation. This type of cardiomyopathy, referred to as tachycardia-induced…
- Valvular heart diseaseTricuspid stenosisTricuspid stenosis is a rare condition that may be caused by rheumatic valvular disease, congenital heart disease, Whipple’s disease, or tumors. Rheumatic…
- Valvular heart diseaseTricuspid regurgitation (TR/TI)The tricuspid valve separates the right ventricle and the right atrium. It normally consists of three leaflets anterior, posterior and septal leaflet. The…
- Valvular heart diseasePulmonary regurgitationPulmonary regurgitation is also called pulmonic regurgitation.
- Valvular heart diseasePulmonary stenosisPulmonary stenosis is virtually always a consequence of congenital heart disease. The stenosis can be fixed or dynamic, depending on the underlying…
- Valvular heart diseaseMitral regurgitationThe most common cause of mitral regurgitation in high-income countries is age-related degeneration of the valvular apparatus. Age-related degeneration…
- Valvular heart diseaseMitral valve stenosisThe mitral valve separates the left atrium and the left ventricle. The valve is attached to the mitral annulus, which is continuous with annulus fibrosus…
- Valvular heart diseaseAortic regurgitationAortic regurgitation implies that the aortic valve leaks during diastole, such that blood regurgitates back from the aorta into the left ventricle. This…
- Valvular heart diseaseAortic stenosisThe aortic valve area is normally 3.0 to 4.0 cm2. Aortic stenosis is a progressive disease that leads to a gradual reduction in the orifice area. As the…
- Miscellaneous conditionsCongenital heart disease & GUCH (Grown Up Congenital Heart disease)Survival in congenital heart disease CHD has increased dramatically over the past few decades. This has resulted in an increased prevalence of congenital…
- Miscellaneous conditionsCardiac thromboembolism: cardiac sources of embolismThromboembolism is a leading cause of death worldwide 1. Emboli originating in the atria, left atrial appendage LAA, ventricles, valves, and proximal aorta…
- Miscellaneous conditionsEndocarditis: definitions, causes, diagnosis, echocardiography & treatmentEndocarditis implies that a bacterial infection engages the heart valves and this is a serious condition. The focus of infection on the flap is called…
- Miscellaneous conditionsRight ventricular strain: definition, causes, echocardiographyWhen assessing the right half of the heart, it is important to familiarize yourself with the principles of hemodynamics and conditions prevailing on the…
- Miscellaneous conditionsCardiac tumorsCardiac tumors are rare. They can occur anywhere in the heart or surrounding tissue. Tumors can be localized in the myocardium, pericardium, perivalvular…
- Pericardial diseaseConstrictive pericarditis: definition, causes, diagnosis & echocardiographyConstrictive pericarditis is the result of chronic inflammation of the pericardium. In principle, all causes of pericarditis can result in constrictive…
- Pericardial diseasePericardial Effusion & Cardiac tamponadeA long series of conditions can affect the pericardium pericardium. The most common of these are acute pericarditis perimyocarditis, constrictive…
Pacemakers and Cardiac Devices
- Introduction to Cardiac Pacing and Devices: Pacemaker, ICD, CRTThe artificial pacemaker is one of the great medical inventions of the 20th century. Cardiac pacing has evolved from a hazardous experiment in the 1930s, to…
- Components and construction of a pacemakerMyocardium is excitable not only by action potentials originating in the sinus node, but also by external electrical stimuli that drive the cells to…
- Basic cardiac pacing, pacemaker functions and settingsAs previously discussed, myocardium may be excited by external electrical stimuli that drive the cells to threshold. Stimulation threshold is the minimum…
- Indications for pacemakerBradyarrhythmia is the main indication for the implantation of a pacemaker. When…
- Interpretation of Pacemaker ECGAssessing pacemaker function requires knowledge of the mode of pacing, and careful analysis of ECG tracings. Most modern devices are capable of transmitting…
- Assessment of Pacemaker MalfunctionConventional surface ECG can reveal the following types of pacemaker dysfunction:
Pediatric and Neonatal ECG Interpretation
- Introduction to pediatric & neonatal ECG interpretationPediatric and neonatal ECG interpretation follow the same principles as ECG interpretation in adults, but there are important differences. These differences…
- Pediatric aspects of ECG leads & anatomyPrinciples of ECG leads, lead anatomy and electrical vectors have been discussed in the chapter The ECG…
- Interpretation of neonatal and pediatric electrocardiograms (ECG)The neonatal and pediatric electrocardiogram ECG is interpreted using the same principles as in ECG interpretation in adults. The ECG must always be…
- Reference values for pediatric and neonatal ECGThese reference values are the best available for the neonatal period. The intervals are 98% confidence intervals the mean is presented in the parenthesis.…
Sudden Cardiac Arrest and Cardiopulmonary Resuscitation (CPR)
- Introduction to sudden cardiac arrest and resuscitationTerminology of sudden cardiac arrest and resuscitationThis chapter will introduce the most common and essential terms used in resuscitation science, providing a foundation for understanding subsequent chapters.
- Introduction to sudden cardiac arrest and resuscitationIntroduction to cardiac arrestIn 1961 the Journal of the American Medical Association JAMA published an article titled Hearts too good to die JAMA,…
- Introduction to sudden cardiac arrest and resuscitationEpidemiological aspects of cardiac arrestThere are currently several large registries monitoring resuscitation practices. Some data sources also monitor sudden cardiac arrest. The EuReCA…
- Introduction to sudden cardiac arrest and resuscitationThe chain of survival in sudden cardiac arrestTime is the most critical factor for survival in cardiac arrest. Life-saving interventions must be initiated momentarily to maximize the probability of…
- Resuscitation physiology and mechanismsThe 3-phase model of sudden cardiac arrestThe course from sudden cardiac arrest SCA to death follows a pathophysiological process that affects the effectiveness of the interventions. Numerous…
- Resuscitation physiology and mechanismsThe physiology of cardiopulmonary resuscitation (CPR)The forces that drive coronary and cerebral perfusion, and ventilation of the lungs during cardiopulmonary resuscitation CPR differ substantially from…
- Causes of sudden cardiac arrest and deathRisk factors for sudden cardiac arrestThe purpose of discovering and measuring risk factors is to obtain estimates of risk, tailor management according to the risk and monitor risk…
- Causes of sudden cardiac arrest and deathCauses of sudden cardiac arrestIt is commonly stated that approximately 80% of all cardiac arrests are caused by acute or chronic coronary artery disease, with the latter being the most…
- ECG atlas of ventricular tachyarrhythmias in cardiac arrestSudden cardiac arrest: Case 1Each recording presents two leads recorded simultaneously.
- ECG atlas of ventricular tachyarrhythmias in cardiac arrestSudden cardiac arrest: Case 2Each recording presents two leads recorded simultaneously.
- ECG atlas of ventricular tachyarrhythmias in cardiac arrestSudden cardiac arrest: Case 3ECG 1. Sinus rhythm interrupted by ventricular tachycardia VT.
- ECG atlas of ventricular tachyarrhythmias in cardiac arrestSudden cardiac arrest: Case 4ECG 1. Sinus rhythm interrupted by ventricular tachycardia VT.
- ECG atlas of ventricular tachyarrhythmias in cardiac arrestSudden cardiac arrest: Case 5ECG 1. Sinus rhythm interrupted by polymorphic VT.
- ECG atlas of ventricular tachyarrhythmias in cardiac arrestSudden cardiac arrest: Case 6ECG 1. The initial rhythm is atrial fibrillation. The fifth beat is a ventricular premature beat. A ventricular tachycardia VT emerges. As evident,…
- ECG atlas of ventricular tachyarrhythmias in cardiac arrestSudden cardiac arrest: Case 7ECG 1. The underlying rhythm is atrial fibrillation, which is interrupted by polymorphic ventricular tachycardia VT.
- ECG atlas of ventricular tachyarrhythmias in cardiac arrestSudden cardiac arrest: Case 8!/img/2023/11/ventricular-tachycardia-fibrillation-flutter-monomorphic-polymorphic-1-2.webp
- Cardiopulmonary ResuscitationBasic Life Support (BLS) in cardiac arrestBasic life support BLS can be provided by anyone, including laypeople. As shown in Table 1, BLS is an exceptionally effective treatment, with a very low…
- Cardiopulmonary ResuscitationArrhythmias before and during cardiac arrestCardiac arrest is a result of tachyarrhythmia, bradyarrhythmia or asystole. The tachyarrhythmias include ventricular fibrillation VF and pulseless…
- Cardiopulmonary ResuscitationAdvanced cardiopulmonary resuscitation (CPR) - Advanced cardiovascular life support (ACLS)This chapter discusses interventions and evaluations performed during advanced cardiovascular life support ACLS. While basic life support BLS can be…
- Cardiopulmonary ResuscitationInterpretation of ECG after ROSC (Return of Spontaneous Circulation)A standard 12-lead ECG should be recorded in all patients after return of spontaneous circulation ROSC. The purpose of a 12-lead ECG is to detect…
- Cardiopulmonary ResuscitationCare after return of spontaneous circulation (ROSC)Victims of out-of-hospital cardiac arrest OHCA who achieve ROSC in the emergency room ER are transferred to the intensive care unit ICU, coronary care unit…
- Cardiopulmonary ResuscitationShort and long-term prognostication in cardiac arrestNeurons are exceptionally vulnerable to hypoxia and anoxia Casas et al. In cardiac arrest without chest compressions i.e. if cerebral perfusion ceases,…
- Cardiopulmonary ResuscitationAssessment of the pupillary reflex in cardiac arrestIn cardiac arrest, constricted, light-responsive pupils suggest a favorable prognosis. In contrast, dilated, light-unresponsive pupils are indicative of…
- Cardiopulmonary ResuscitationUltrasound (echocardiography) in cardiac arrest and resuscitationIn the context of cardiac arrest, focused echocardiography entails a swift evaluation of ventricular contractions and the status of the pericardium by an…
- Cardiopulmonary ResuscitationCapnography (end-tidal carbon dioxide measurement, ETCO2) during cardiac arrestCapnography refers to the measurement of end-tidal carbon dioxide ETCO2 in the respiratory system. ETCO2 is the partial pressure of carbon dioxide CO2 at…
- Cardiopulmonary ResuscitationExtracorporeal cardiopulmonary resuscitation (ECPR)Survival after cardiac arrest depends on the restoration of spontaneous cardiac rhythm. The likelihood of achieving spontaneous cardiac activity is a…
- Special CircumstancesCardiac arrest in hypothermia (accidental hypothermia)Accidental hypothermia is defined as an unintentional decrease in body temperature to below 35°C. The lowest recorded body temperatures from which patients…
- Special CircumstancesCardiac arrest in hyperthermia and malignant hyperthermiaHyperthermia is characterized by a body temperature exceeding the typical range of 36.5-37.6°C 97.7-99.7°F. It arises when heat production or acquisition…
- Special CircumstancesCardiac arrest due to electrolyte imbalanceSignificant electrolyte imbalances can precipitate cardiac arrest and are potentially reversible etiologies when promptly and appropriately addressed. Both…
- Special CircumstancesCardiac arrest during pregnancy and childbirthAll healthcare units capable of managing pregnant women in cardiac arrest should engage in specialized clinical training to manage cardiac arrest during…
- Special CircumstancesCardiac arrest during sepsisSepsis is a life-threatening condition characterized by systemic inflammatory response syndrome SIRS, disseminated intravascular coagulation DIC, and…
- Special CircumstancesCardiac arrest due to pneumothoraxPneumothorax is characterized by the presence of free air in the thoracic cavity. While this can occasionally be benign and manifest even in healthy…
- Special CircumstancesCardiac tamponade causing cardiac arrestCardiac arrest associated with tamponade has an exceptionally poor prognosis. In the vast majority of these cases, the tamponade develops acutely or…
- Special CircumstancesCardiac arrest due to anaphylaxisAnaphylactic cardiac arrest is managed following the cardiopulmonary resuscitation CPR algorithm, incorporating an intravenous administration of 1 mg…
- Special CircumstancesCardiac arrest in intoxication (poisoning)In adolescents and young adults, intoxication events leading to cardiac arrest are notably prevalent, primarily due to the misuse of prescription…
- Special CircumstancesCardiac arrest due to hypoxia and asphyxiaEtiologies of hypoxic cardiac arrest:
- Special CircumstancesTraumatic cardiac arrestIn cases of traumatic cardiac arrest, addressing reversible etiologies takes precedence over chest compressions. If trauma is not definitively established…
The Normal ECG: From Normality to Pathology
- Approach to ECG Interpretation, Assessment of Rhythm and the P-waveApproach to ECG Interpretation, Assessment of Rhythm and the P-wave
- The PR Interval & PR segmentThe PR interval stretches from the onset of the P-wave to the onset of the QRS complex. It reflects the time interval from start of atrial activation…
- The QRS Complex: Q-wave, R-wave, S-wave, R-wave progressionThe QRS Complex: Q-wave, R-wave, S-wave, R-wave progression
- The ST segment: J-point, J-60 point, ST depression, ST elevationThe ST segment: J-point, J-60 point, ST depression, ST elevation
- The T-wave: T-wave inversions, hyperacute T-waves, large T-waves, flat T-wavesThe T-wave: T-wave inversions, hyperacute T-waves, large T-waves, flat T-waves
- The QT and QTc IntervalThe QT and QTc Interval
- The Electrical Axis of the HeartThe Electrical Axis of the Heart