General Cardiology

Cardiovascular Medicine

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Figure 2. Two ECGs showing left and right ventricular hypertrophy.

ECG

Right ventricular hypertrophy (RVH): ECG criteria & clinical characteristics

ECG and clinical characteristics in right ventricular hypertrophy (RVH) Right ventricular hypertrophy

Echocardiography

The ultrasound transducer

The ultrasound transducer & piezoelectric crystals The ultrasound transducer generates

Figure 1. ECG changes seen in left ventricular hypertrophy (LVH) and right ventricular hypertrophy (RVH). The electrical vector of the left ventricle is enhanced in LVH, which results in large R-waves in left sided leads (V5, V6, aVL and I) and deep S-waves in right sided chest leads (V1, V2). Right ventricular hypertrophy causes large R-waves in right sided chest leads and deeper S-waves in left sided leads.

ECG

ECG in left ventricular hypertrophy (LVH): criteria and implications

ECG and clinical characteristics in left ventricular hypertrophy (LVH) The following

Echocardiography

Physics of ultrasound

Basic sound and ultrasound physics Unlike light waves, which can

Atrial and ventricular enlargement: hypertrophy and dilatation on ECG

Principles of atrial and ventricular enlargement (hypertrophy and dilatation) Cardiac

Evaluation of chronic coronary syndromes (angina pectoris, coronary artery disease)

ECG

Stable Coronary Artery Disease (Angina Pectoris): Diagnosis, Evaluation, Management

Evaluation and management of stable coronary artery disease Chronic coronary

Hypertension: Causes, investigations, complications & treatment

Hypertension is the leading cause of morbidity and mortality worldwide.

Pathophysiology of pulmonary embolism (PE).

Thromboembolism

Pulmonary Embolism (PE)

Pulmonary embolism occurs when venous thrombi embolize to the pulmonary

Heart failure

Heart failure: Causes, types, diagnosis, treatments & management

Heart failure Heart failure is a major public health problem

Information

Cardiovascular effects of COVID-19 (Coronavirus Disease 2019)

Cardiovascular effects of COVID-19 Coronavirus disease 2019 (COVID-19) has caused

ECG non-specific nonspecific intraventricular conduction delay

Arrhythmology

Nonspecific intraventricular conduction delay (defect)

Nonspecific intraventricular conduction delay A nonspecific intraventricular conduction delay exists if

Figure 1. Left anterior fascicular block (hemiblock) and left posterior fascicular block (hemiblock). Inspired by GS Wagner (Marriott's Practical Electrocardiography, Elsevier 2007) and AL Goldberg (Clinical Electrocardiography: A Simplified Approach, Elsevier Mosby 2006).

Arrhythmology

Fascicular block (hemiblock): Left anterior & left posterior fascicular block

Fascicular block (hemiblock): left anterior fascicular block & left posterior

Figure 1. ECG criteria (Sgarbossa criteria) for acute STEMI in the setting of LBBB. Each criteria gives 2 to 5 points. Studies show that a cut-off of ≥3 points yields a sensitivity of 20–36% and specificity of 90–98% for acute STEMI in the setting of LBBB.

ECG

Left bundle branch block (LBBB) in acute myocardial infarction: the Sgarbossa criteria

Left bundle branch block (LBBB) in acute myocardial infarction (AMI): clinical

Figure 2. Right bundle branch block (RBBB) and left bundle branch block (LBBB). Note that the paper speed is 50 mm/s (1 large box equals 100 ms). The hallmark of both RBBB and LBBB is the QRS duration which is by definitions 120 ms or longer. The distinction between RBBB and LBBB is simple, as illustrated in this figure.

Arrhythmology

Right bundle branch block (RBBB): ECG, criteria, definitions, causes & treatment

Right bundle branch block (RBBB) Right bundle branch block (RBBB)

Figure 1. These ECGs show the difference between normal conduction, left bundle branch block (LBBB) and right bundle branch block (RBBB). As evident from these ECGs, the cardinal difference between normal conduction and bundle branch blocks is the QRS duration: bundle branch blocks are caused by dysfunctional bundle branches, which results in slow (and abnormal) activation of ventricular myocardium and thus prolonged QRS duration. A QRS duration of 120 ms (0.12 s) is required to diagnose bundle branch block. Also note that both left bundle branch block (LBBB) and right bundle branch block (RBBB) cause marked ST-T changes, including ST elevations, ST depressions and inverted (negative) T-waves. These ST-T changes are due to abnormal repolarization and they are expected to occur in both LBBB and RBBB. Finally, note that there are marked difference in the ECG pattern between LBBB and RBBB. These ECGs are printed at paperspeed 50 mm/s.

Arrhythmology

Left bundle branch block (LBBB): ECG criteria, causes, management

Left bundle branch block (LBBB): ECG criteria and clinical implications

Figure 1. Components of the ventricular conduction system and the temporal association between the ECG and impulse transmission through the heart. An intranventricular conduction delay may occur whenever any of the main components of the conduction system is dysfunctional.

Arrhythmology

Intraventricular conduction delay: bundle branch blocks & fascicular blocks

Intraventricular conduction delay (defect): constellations of bundle branch blocks and fascicular

Management of AV blocks (treatment)

Arrhythmology

Management and treatment of AV block (atrioventricular blocks)

Management and treatment of AV blocks (AV-block 1, 2 &

Figure 1. Third-degree AV block (complete heart block, AV dissociation).

Arrhythmology

Third-degree AV block (3rd degree AV block, AV block 3, AV block III)

Third-degree (complete) AV block: ECG criteria, clinical characteristics and management

Figure 1. Second-degree AV block Mobitz type 1, also known as Wenckebach block.

Arrhythmology

Second-degree AV block: Mobitz type 1 (Wenckebach) & Mobitz type 2 block

Second-degree AV block: ECG criteria, clinical characteristics & management In

Figure 1. ECG in first-degree AV block. Both conventional paper speeds are shown.

Arrhythmology

First-degree AV block (AV block I, AV block 1)

First-degree AV block: ECG criteria, clinical characteristics & management In

Figure 1. Components of the ventricular conduction system and the temporal association between the ECG waveforms and impulse transmission through the heart. Atrioventricular (AV) blocks occur due to dysfunction in the conduction system.

Arrhythmology

Overview of atrioventricular (AV) blocks

Atrioventricular block (AV block): definition, causes, diagnosis & management This

Failure to pace.

Cardiac device therapy

Assessment of Pacemaker Malfunction

Pacemaker malfunction, troubleshooting and ECG Conventional surface ECG can reveal

Indications for pacemaker

Indications for pacemaker implantation Bradyarrhythmia is the main indication for

Cardiac device therapy

Basic cardiac pacing, pacemaker functions and settings

Stimulation threshold As previously discussed, myocardium may be excited by

Cardiac device therapy

Interpretation of Pacemaker ECG

Interpreting pacemaker ECGs Assessing pacemaker function requires knowledge of the

Figure 1. Components of a pacemaker.

Cardiac device therapy

Components and construction of a pacemaker

Principles of myocardial excitability Myocardium is excitable not only by

The electrical conduction system.

Cardiac device therapy

Introduction to Cardiac Pacing and Devices: Pacemaker, ICD, CRT

The artificial pacemaker is one of the great medical inventions

Figure 1. Cross-sectional view of ventricular wall thickness in children (

ECG

Introduction to pediatric & neonatal ECG interpretation

Principles of pediatric & neonatal ECG interpretation Pediatric and neonatal

Figure 1. The ECG grid. The x-axis represents time and y-axis represents amplitude of the electrical signals generated in the myocardium. The same ECG grid is used in children and adult patients.

ECG

Pediatric aspects of ECG leads & anatomy

ECG leads and recording ECGs in pediatric patients (children) Principles

Reference values for pediatric and neonatal ECG

Neonatal period Table 1. Normal limits for ECG parameters during

Interpretation of neonatal and pediatric electrocardiograms (ECG)

Definition of normal and pathological pediatric and neonatal ECG The

Long QT Syndrome (LQTS)

Please refer to the previous chapter: LQTS (Long QT Syndrome)

ECGs showing acute STEMI in two patients with severe chest pain. STEMI = ST elevation Myocardial Infarction.

ECG

STEMI (ST Elevation Myocardial Infarction): diagnosis, criteria, ECG & management

STEMI (ST Elevation Acute Myocardial Infarction): Epidemiology, Diagnosis (ECG), Criteria

ECG

NSTEMI (Non ST Elevation Myocardial Infarction) & Unstable Angina: Diagnosis, Criteria, ECG, Management

Non ST Elevation Acute Coronary Syndromes (NSTE-ACS): Non ST Elevation

Figure 1. Chest pain is the hallmark of myocardial ischemia. It signals that there is ongoing (acute) myocardial ischemia. Careful assessment of the symptoms is crucial to promptly establish a working diagnosis. Chest pain due to myocardial ischemia is rather characteristic, which means that the vast majority of patients with acute coronary syndromes can be treated before troponin test results have arrived. Hence, assessment of symptoms and ECG is sufficient to manage patients with chest pain.

ECG

Approach to patients with chest pain: differential diagnoses, management & ECG

Approach to patients with chest pain: differential diagnoses, evaluation and management

Figure 2. The electrocardiographic natural course in STEMI (ST elevation myocardial infarction).

ECG

The ECG in assessment of myocardial reperfusion

The ECG in assessment of myocardial reperfusion The ECG is

Figure 1. The coronary arteries and their relation to the ECG leads. Localization of myocardial infarction / ischemia is done by using ECG changes to determine the affected area and subsequently the occluded coronary artery (culprit).

ECG

ECG localization of myocardial infarction / ischemia and coronary artery occlusion (culprit)

Using the ECG to localize myocardial infarction / infarction and determine the

Figure 1. The component of the cardiac conduction system and the vascular supply. RCA = right coronary artery. LAD = Left anterior descending coronary artery. LCX = left circumflex coronary artery.

ECG

Supraventricular and intraventricular conduction defects in myocardial ischemia and infarction

Conduction defects caused by myocardial ischemia and infarction Bradycardia and

Figure 1. Pathological R-wave progression is indicative of previous myocardial infarction.

ECG

Other ECG changes in ischemia and infarction

Pathological R-wave progression Normal R-wave progression implies that the R-wave

Figure 1. Examples of STE-ACS (STEMI). Note that these patients presented with pathological Q-waves, which means that these ECGs were recorded several hours after symptom onset or those are signs of old infarction.

ECG

ECG signs of myocardial infarction: pathological Q-waves & pathological R-waves

Pathological Q-waves are evidence of myocardial infarction Myocardial infarction – particularly

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Clinical ECG Interpretation

From cell to reperfusion