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

…This is due to altered tone in the autonomic nervous system, with increased sympathetic input (leading to stimulation of beta adrenergic receptors) and parasympathetic withdrawal…

…due to atrial fibrillation with wide QRS complexes due to bundle branch blocks or other conduction defects. However, in rare instances, it may be due…

…Due to this rapid clearance, adenosine must be administered as a rapid intravenous bolus. Unlike many other intravenous medications where rapid boluses risk hemodynamic instability…

…of the QRS complexes vary from one beat to another (in the same lead). This is due to the swinging back and forth of the…

…of the R waves. This is believed to be due to delayed (and thus electrically unopposed) depolarization in the ischemic area. Fragmented QRS complex The…

…and infarction Use of ECG in acute coronary syndromes & chest pain patients An ECG must be performed on all patients seeking medical attention due to…

…Furthermore, sudden cardiac arrests account for 50% of all years of life lost due to cardiovascular disease ( Myerburg et al ). Sudden unexpected cardiac arrest is…

…may also arise due to extensive subendocardial infarction (NSTEMI). If pathological Q waves occur as a result of myocardial infarction, the infarction may be classified…

…to infarction due to the collaterals. Occasionally, patients with total and proximal occlusions may present without ST segment elevations (which they should exhibit) due to…

…to distinguish Type 2 MI from acute and chronic myocardial injury. Myocardial injury is characterised by myocyte necrosis and troponin elevation due to mechanisms other…

…the thrombus and the plaque. The patient will experience severe chest pain due to the abrupt reduction of coronary blood flow. Acute coronary syndromes are…

…myocardial infarction/ischemia. Most patients, however, display both ECG changes and symptoms. Troponins and other biomarkers of myocardial necrosis (infarction) Myocardium can endure 20 to…

…progress to myocardial infarction within 30 days if left untreated. Moreover, the pathophysiology of NSTEMI and unstable angina is very similar: both are due to…

…ischemia is due to a complete and proximal artery occlusion and such occlusions must be managed with immediate PCI (Percutaneous Coronary Angiography). Transmural ischemia (infarction)…

ECG Myocardial ischemia and infarction ST segment depression due to acute myocardial ischemia ST segment depressions caused by ischemia are characterized by a horizontal or…

Indications Acute myocardial infarction. Unstable coronary artery disease. Stable angina pectoris. Secondary prophylaxis to prevent recurrence of cerebrovascular diseases, such as: Transient ischemic attacks (TIA…

…versa ( Figure 17 ). Otherwise there is discordance (opposite directions of QRS and T) which might be due to pathology. A negative T wave is also…

…other causes of left axis deviation have been excluded. Causes of extreme axis deviation Extreme axis deviation is rare. It is most likely due to…

…s, provided that other causes of left axis deviation have been excluded. Causes of extreme axis deviation Rare. Most likely due to misplaced limb electrodes…

…of the QRS complex. Due to this it is sometimes recommended that ST segment deviation be measured in the J 60 point, or J 80…

…are mostly due to acute myocardial ischemia or myocardial infarction, and in these cases, the likelihood of ROSC is higher as compared to other etiologies…

…health effects of hypertension are devastating. Due to the simplicity of diagnosing hypertension and the effectiveness of antihypertensive treatments, targeting hypertension is the single most…

…is thought to involve the sensitization of sensory nerve endings due to the accumulation of bradykinin. ACE is responsible for metabolizing bradykinin and other tachykinins…

…cardiac arrest. In order for an infarction or ischemic episode to result in ventricular arrhythmia, it must coincide with other pro arrhythmogenic factors. The emergence…

…with previous acute coronary syndromes (ACS) Exercise stress testing is routinely performed after acute myocardial infarction in order to assess the presence of myocardial ischemia…

…a prior inferior infarction. Left posterior fascicular block (LPFB) Left posterior fascicular block is much less common than LAFB. This is due to the fact…

…with homozygous FH typically die from acute myocardial infarction at 20 to 30 years of age. People with familial hypercholesterolemia have no other metabolic aberration…

…with ECG may reveal atrial fibrillation. Unfortunately, atrial fibrillation is too often discovered first at hospital admission due to its complications (stroke, thromboembolism, heart failure…

…after myocardial infarction), most likely has a parietal thrombus. The presence of ecotdense masses on valves should lead to suspicion of endocarditis (the masses are…

…instability. Fewer than 1% of patients with ST elevation myocardial infarction (STEMI) who reach the catheterization laboratory are found to have complete LMCA occlusion, likely…

…of aggravating the infarction, as well as inducing ventricular arrhythmias. Unstable angina pectoris in the acute phase (before stabilization of symptoms) – due to the risk…

…due to diminished automaticity (pacemaker function) in the sinoatrial node or conduction defects (e.g. second degree AV block) as a result of ischemia/infarction…

…infarction. Hyperkalemia. Treatment of sinoatrial arrest/pause Sinus arrest/pause due to increased vagal tone does not necessitate treatment but it might be wise to…

…favorable prognosis, as compared with other forms of ventricular tachycardia. Mechanisms of ventricular tachycardia Ventricular tachycardia (VT) may emerge due to increased/abnormal automaticity, re…

…classification comprises five groups: Group 1: Pulmonary arterial hypertension Group 2: PH due to left heart disease Group 3: PH due to chronic lung disease…

…on the bowel must be taken into account). Known allergy to the preparation — rare; itching and urticaria are usually due to histamine release, not allergy…

…elevation myocardial infarction. Due to their clinical presentation, these patients are immediately referred to angiography but no coronary artery occlusion can be identified. Injection of…

…the anterior axillary line. Thoracostomy This method is generally deemed safer than using a needle due to reduced risk of injury. Thoracostomy should be performed…

…World Heart Federation (WHF) collaborated to redefine MI using a biochemical and clinical approach. This culminated in the Universal Definition of Myocardial Infarction Consensus Documents…

…resulted in myoardial infarction. An important discovery was reported in 1930 when Buchner and colleages showed that myocardial contractility was closely related to myocardial blood…

…tachycardia and ventricular fibrillation cause the vast majority of all deaths in the acute phase of STEMI. Death due to ventricular dysfunction, or mechanical complications…

…affected, then the left ventricle is virtually always affected due to the coronary anatomy (refer to the chapter Coronary Arteries and Localization of Infarction & Ischemia)…

…of posterior acute myocardial infarction (e.g due to reciprocal ST segment depressions in V1, V2, V3). IIa B In patients with inferior myocardial infarction…

CPR Cardiac arrest due to trauma In cases of traumatic cardiac arrest, addressing reversible etiologies takes precedence over chest compressions. If trauma is not definitively…

Enalaprilat Enalaprilat is rarely used in hypertensive crisis due to its slow onset, prolonged duration of effect, and significant individual variations in its effect. Drug…

Hydralazine Hydralazine is not preferred for hypertensive emergencies due to the high risk of reflex sympathetic stimulation. Drug Hydralazine Brand names Apresoline ®, Bidil ®…

…employed due to aspiration risks and inconclusive evidence. However, in cases of iron, lithium, or potassium intoxication where lavage might prove beneficial, the procedure should…

Cardiology Indications for pharmacologic agents Pharmacologic stress tests are indicated in the following scenarios: Inability to exercise due to physical limitations. Contraindications to exercise, such…

…sinus node dysfunction Age related degenerative disease (fibrosis) Myocardial ischemia/infarction Lesions due to heart surgery Myocarditis Collagen disease Amyloidosis Risk of supraventricular tachyarrhythmia (tachycardia…

…repeated intravenous bolus injections or as a constant dose infusion. Bolus regime : • 20 mg IV bolus over 2 minutes, followed by 20 to 80 mg…

…severe bleeding. Particular caution is required for: Patients aged ≥ 75 years. Patients with a tendency to bleed (e.g., due to recent trauma, surgery, gastrointestinal…

…often recommended for PCI, while those with high scores (≥33) are typically advised to undergo CABG due to better long term outcomes. Intermediate scores (23…

…suspicion of syncope due to an arrhythmia or underlying cardiac disease. Relevant abnormalities include bradyarrhythmias or tachyarrhythmias, AV block, acute myocardial ischemia, old myocardial infarction…

…Ventricular rupture : A transmural infarction can cause a rupture in the left ventricular free wall. Mediastinal trauma : Penetrating injuries to the mediastinum can cause tamponade…

…The atrial impulse must pass through the atrioventricular node, which delays the impulse due to its slow conduction, before the impulse may reach the ventricles…

…Causes of tricuspid regurgitation The most common causes of tricuspid regurgitation are as follows: Right ventricular dysfunction due to pressure/volume overload. Right ventricular infarction…

…fraction (LVEF). Sustained VT: Defined as VT lasting longer than 30 seconds or requiring termination earlier due to hemodynamic collapse [4] . Sustained VT is a…

…materials pose a high risk of infection. Approximately 20% of all endocarditis affect people with valve prostheses and among other cases 18% show significant valvular…

…a blood gas, coagulation tests and other investigations according to the clinical picture 5 Take cultures or molecular tests from the suspected focus, but avoid…