…Narrow complex tachycardias (QRS duration <0,12 seconds) indicate the ventricles are depolarized via the His Purkinje system and thus the impulse originates in the…

…Cardiac troponin levels are extremely low in healthy subjects; the 99 th percentile is less than a few nanograms per liter of blood (typically <5…

Cardiology Introduction Ventricular tachycardia (VT) represents a complex and potentially lethal spectrum of cardiac arrhythmias that remains a formidable challenge in contemporary cardiovascular medicine. As…

…ventricular rate slower than 50 beats per minute. P waves with constant morphology preceding every QRS complex. P wave is positive in limb lead II…

…heart rate 50–100 beats per minute; (2) P wave precedes every QRS complex; (3) the P wave is positive in lead II and (4…

…catheterization. Principles of management of congenital heart disease and GUCH Complex malformations often require intervention (surgical or catheter based intervention). In addition to the malformation…

…heart rate 50–100 beats per minute; (2) P wave precedes every QRS complex; (3) the P wave is positive in lead II and (4…

…demonstrated that these parameters are highly interdependent and rather complex. Indeed, myocardial mechanics constitute a whole research field. Cardiac function is also dependent on circulatory…

…For example, Bazett's formula is only suitable in adults with a heart rate between 60 and 90 beats per minute. Bazett's formula over…

…depolarization in these cells is 60 beats per minute. The resulting P wave is morphologically different from the sinus P wave, but the QRS complex…

CPR This chapter will introduce the most common and essential terms used in resuscitation science, providing a foundation for understanding subsequent chapters. SCA (Sudden Cardiac…

…essential to reconfirm the rhythm in two leads if possible to distinguish true bradyarrhythmic or asystolic arrest from other tachyarrhythmic events. On the surface electrocardiogram…

…2%–0.5% per year beyond the first year, although the available material does not establish a significant increase in late morbidity or mortality attributable…

…QRS complex; atrioventricular block is uncommon unless the patient is receiving digoxin. The ventricular rate is regular, typically ranging from 100 to 250 beats per…

…rhythm with ventricular rate 100 beats per minute. P wave with constant morphology preceding every QRS complex. The P wave is positive in lead II…

…T changes on ECG). Hence, all beats and rhythms arising in the ventricles will display discordant ST T segments, meaning that the QRS complex and…

…each QRS complex then it is 2:1 block. In typical cases of atrial flutter, the atrial rate is around 300 beats per minute with…

…150 and 250 beats per minute. The P wave is not visible in most cases, because it is hidden within the QRS complex (the atria…

…The cells of the sinus node have an intrinsic rate of depolarization at approximately 70 times per minute, which results in 70 contractions per minute…

…aVF) will be seen after the QRS complex. Junctional beats and junctional rhythm Junctional rhythm may arise in the following situations: If the normal sinus…

…how the P wave and QRS complex are generated by the electrical vectors. Note that the first vector in Figure 7 is not discussed here…

ECG Video lecture: The QRS complex: Q wave, R wave & S wave

…). Premature atrial contraction on ECG A premature atrial contraction occurs when an ectopic focus in the atria discharges before the next sinus impulse. The premature…

…on premature ventricular complexes; the ST T vector will be directed oppositely to the QRS vector. As seen in Figure 1 the premature ventricular complex…

…the P wave to the onset of the QRS complex. The PR interval is assessed in order to determine whether impulse conduction from the atria…

[calc_syntax] SYNTAX Score: A Tool for Revascularization Strategy in Complex Coronary Artery Disease The SYNTAX Score is a semi quantitative scoring system designed to…

Cardiology Definition and terminology Heart failure (HF) is a complex clinical syndrome characterized by symptoms and signs resulting from structural or functional impairment of ventricular…

…progressive, and highly complex lipid driven inflammatory disease of the arterial intima that serves as the fundamental pathophysiological substrate for acute coronary syndromes (ACS), including…

Arrhythmias and arrhythmology Pharmacology & dosing Pharmacokinetic Considerations Relevant to Dosing Amiodarone exhibits highly variable and complex pharmacokinetics that profoundly influence its dosing strategies. The drug…

…Definition and pathophysiology Obesity is a chronic, relapsing and biologically complex disease characterized by excessive accumulation of adipose tissue. It is an important cause of…

…fraction (HFpEF) is a complex clinical syndrome characterized by the cardinal symptoms and signs of heart failure (HF) in the presence of a left ventricular…

…R or Rs complex suggests VT. If the QRS complex in V1–V2 resembles a left bundle branch block (i.e negative QRS) V1 : The…

…age, while its clinical expression and management become progressively more complex. Older adults, often defined in cardiovascular practice as those older than 75 years, are…

…on the ECG. Its height (amplitude) is approximately one fourth of the amplitude of the T wave. The U wave is most often seen in…

…or aberrancy. Narrow complex tachycardia where the P waves cannot be discerned on the surface ECG and the RP interval decides between AVNRT, orthodromic AVRT…

…wide QRS complex and a pulse that can be felt. The other predictable error is forgetting that pacing hurts a great deal in a conscious…

…recovery patterns within the left ventricle, resulting in a widened QRS complex and secondary ST T wave abnormalities [7]. Diagnostic Criteria The diagnostic requirements for…

…for depolarization and repolarization. It is measured from the beginning of the QRS complex to the end of the T wave. Prolonged QT duration predisposes…

…shock delivered asynchronously on the T wave during ventricular tachycardia can precipitate ventricular fibrillation, whereas a synchronized shock (timed to the QRS complex) avoids this…

…seconds. Case reports have indicated that the risk of high degree AV block and ventricular arrhythmias is greater in patients on digoxin or verapamil, although…

…evolved significantly; it is no longer viewed merely as an electrical anomaly but as a progressive, complex atrial myopathy. For the practicing cardiologist, mastering the…

…thereby the impulse delay in the AV node. Therefore, the ventricles will be activated (depolarized) earlier than expected, which is reflected on the ECG by…

…100/min; a P wave precedes every QRS complex; the PR interval is constant and the P wave is positive in lead II. Causes of…

…Heart rate Heart rhythm The P wave The PR interval The QRS complex The ST segment The T wave The U wave The QT interval…

…assessment. Validated in large clinical trials, including the SYNTAX trial. Limitations Requires detailed clinical and angiographic data. Calculation can be complex without dedicated software. May…

…objective, particularly in patients with left ventricular dysfunction and/or MVD. Nevertheless, the optimal extent and timing of intervention depend on the clinical setting, haemodynamic…

…stenoses. Higher scores indicate more diffuse or technically complex disease and are associated with a greater relative advantage for CABG over PCI in multivessel disease…

…Left anterior fascicular block is diagnosed if the axis is between 45° and 90° with qR complex in aVL and QRS duration 0,12 s…

…anterior fascicular block is diagnosed if the axis is between 45° and 90° with qR complex in aVL and QRS duration is 0,12 s…

…single) T wave inversion in lead V1 is common and normal. It is generally concordant with the QRS complex (which is negative in lead V1)…

…is complex. Glycaemic control is important for prevention of microvascular complications, but intensive glucose lowering alone has shown little or no consistent effect on cardiovascular…

…waveforms presented here. Activation of the atria is reflected as the P wave and activation of the ventricles results in the QRS complex. The T…

…may increase. QRS complex QRS duration becomes prolonged. ST segment ST segment depression may develop. T wave T wave may diminish in amplitude. U wave…

…a delay in the propagation of electrical impulses from the atria to the ventricles. This delay is characterized by a prolonged PR interval on the…

…However, a growing body of science suggests that essential hypertension is a multifactorial disease caused by a complex interplay between genes and environment. Industrialization and…

…normal interval. P wave with constant morphology preceding every QRS complex. The P wave is positive in lead II (and also I and aVF). Arrhythmias…

…waves in lead II. QRS Complex QRS morphology also depends on where the pacing stimulus is delivered. Typically, the lead tip is fixed apically in…

…complex. These QRS configurations are also indicate of previous myocardial infarction. New conduction defect Myocardial infarction/ischemia may be complicated with conduction defects (discussed in…

…stimulate both ventricles simultaneously). A tachycardia with Q wave or QS complex in lead I suggest that the tachycardia is caused by the CRT device.

…abnormal activation sequence of the right ventricle, resulting in a prolonged and abnormal QRS complex on the ECG. The hallmark of right bundle branch block…