Presentation
Sudhansu Chokroverty—a world-recognized expert in sleep medicine—presents the third edition of Sleep Disorders Medicine for the latest developments in this rapidly expanding specialty, with coverage of neuroscience and clinical application. [books.google.com]
In some patients with VT, they may not be in a state of collapse, but present with dizziness, palpitations, syncope, chest pain or heart failure. Some patients with SVT and poor ventricular function may present in a state of haemodynamic collapse. [patient.info]
If the aberrancy is conducted in a RBBB pattern, right axis deviation will be present. If the aberrancy is conducted in a LBBB pattern, left axis deviation will be present. [emsworld.com]
R S complex is present, and the longest precordial RS interval is > 100 msec in one or more precordial leads VT present; stop and treat Proceed to 3 3. Atrioventricular dissociation is present VT present; stop and treat Proceed to 4 4. [aafp.org]
However, tachycardias with a supraventricular origin can present as a BCT when associated with aberrant conduction or a pre-existing bundle branch block (see Figures 8 and 9). [rcemlearning.co.uk]
Entire Body System
- Intravenous Administration
A delayed diagnosis of VT or a misdiagnosis followed by inappropriate intravenous administration of drugs used for the treatment of SVT, such as verapamil and adenosine, can cause severe hemodynamic deterioration and may provoke ventricular fibrillation [e-arrhythmia.org]
- Swelling
There were abrasions to the right thigh, and pain and swelling in the right leg. 0739-0800 : Pillar and car door cut away, and patient put onto spinal board The patient received a total of 1.5 L of crystalloid intravenously (IV) and 7.5 mg of morphine [ecgmojo.com]
Respiratoric
- Cough
Coughing can cause or break it: Give adenosine and the problem is fixed 5. Rate: 150-250 bpm 6. No visible P-waves, except possible retrograde P-waves present. 7. Look at baseline EKG for Pre-excitation (Wolf-Parkinson-White) 8. [quizlet.com]
Cardiovascular
- Tachycardia
Ventricular Tachycardia in Nonischemic Dilated Cardiomyopathy 535 Electrocardiogram Characteristics of Outflow Tract Ventricular Tachycardia 553 Fascicular Tachycardia 567 Ventricular Tachycardia Originating from Unusual Sites 581 Electrocardiographic [books.google.com]
[…] are satisfied, ventricular tachycardia is diagnosed by default. [en.ecgpedia.org]
[…] supraventricular, supraventricular tachycardias, Supraventricular tachycardia (SVtach), Supraventricular tachycardia NOS (disorder), SVT - Supraventricular tachycardia, Supraventricular tachycardia (disorder), supraventricular; tachycardia, tachycardia [fpnotebook.com]
Treating supraventricular tachycardia with aberrancy as though it were ventricular tachycardia is not dangerous; however, treating ventricular tachycardia as though it were supraventricular tachycardia with aberrancy can make a bad situation worse. 1,3 [consultant360.com]
- Heart Block
Yes = VT (Sensitivity 0.82, specificity 0.98) No = Next Question AV Dissociation = Ventricular rate is same or faster than the atrial rate Complete Heart Block = Atria are beating independent of ventricles with atrial rate being faster than ventricular [foamem.com]
Blockage of impulse conduction in either of the bundles produces the characteristic ECG pattern of a bundle branch block. Blockage in the AV node, Bundle of His, or both bundles results in complete AV dissociation or third-degree heart block. [ahcmedia.com]
[…] rub Pericarditis resulting in tachycardia Third heart sound Heart failure causing tachycardia Cannon waves Possible atrioventricular nodal reentrant tachycardia or ventricular tachycardia Respiratory Crackle Heart failure resulting in tachycardia Endocrine [aafp.org]
Skin
- Flushing
Some of the more common complaints include palpitations, lightheadness/dizziness, dyspnea, chest discomfort, flushing, presyncope and rarely syncope. [clinicaladvisor.com]
[…] medial management Unstable signs/symptoms include Altered mental status Acute cardiogenic pulmonary edema Ischemic chest pain (doesn’t include any wimpy CP) Hypotension PEARL: Adenosine dosing for SVT generally begins with 6mg IV push (fast with a rapid flush [maryland.ccproject.com]
90-95% of those treated with 12 mg. 11 Dose range for pediatric populations is 100-250 micrograms/kg IV bolus. 7 Adenosine has an extremely short therapeutic duration (about 10 seconds), so it is administered via a rapid IV push followed by a saline flush [ahcmedia.com]
Workup
Disposition: The vast majority of patients with an episode of ventricular tachycardia should be admitted to the hospital (preferably a high-acuity setting) for further workup with cardiology or electrophysiology. [emdocs.net]
Table 4 lists items to include in a focused examination and diagnostic workup. Enlarge Print Table 4. [aafp.org]
Syncope or severe symptoms occurring with palpitations, should always result in a formal cardiac workup. Syncope only occurs in about 15% of patients with SVT. [clinicaladvisor.com]
QRS Wave
- Wide QRS Complex
Adapted from [ 1 ] ECG algorithms to differentiate wide QRS-complex tachycardias Several ECG algorithms have been developed to differentiate wide QRS-complex tachycardias. Most of them performed very well in the population they were based upon. [en.ecgpedia.org]
Ventricular tachycardia: diagnosis of broad QRS complex tachycardia. Heart 2001;86:579-85 [ Links ] 2. VERECKEI A. Current algorithms for the diagnosis of wide QRS complex tachycardias. Current Cardiology Review 2014;10:262-276 [ Links ] 3. [scielo.cl]
If the impulse is too premature, it may find one of the bundle branches still refractory from the previous impulse and will be conducted with a wide QRS complex. these premature atrial impulses that are followed by wide QRS complexes are aberrantly conducted [afghanheart.wordpress.com]
This results in bundle branch block and hence " wide QRS complex ". Clinical significance Identification of the wide QRS complex as aberration helps to exclude the diagnosis of VPS. ECG 1a. [metealpaslan.com]
Several criteria have been described for differentiation between VT and SVT in the presence of a wide QRS complex. We report a case of wide QRS complex tachycardia with left BBB (LBBB) morphology and a retrograde P wave on the surface ECG. [e-arrhythmia.org]
Rhythm
- Atrioventricular Dissociation
Clinical evidence of atrioventricular dissociation, ie cannon waves in the jugular venous pulse or variable intensity of the first heart sound, indicates a VT. Physical signs will also vary according to the haemodynamic effects of the tachycardia. [patient.info]
Atrioventricular dissociation and the presence of capture or fusion beats are essentially diagnostic of ventricular tachycardia and almost all patients with a history of myocardial infarction have ventricular tachycardia, not supraventricular tachycardia [consultant360.com]
Atrioventricular dissociation is present VT present; stop and treat Proceed to 4 4. [aafp.org]
Treatment
In addition to summarizing basic science and important technological aspects of diagnosis and treatment, this edition presents new chapters—on sleep and memory consolidation, neuroimaging, and more—in a color layout that makes it easy to access the latest [books.google.com]
Treatment: In any patient compromised by their monomorphic VT the treatment of choice is DC cardioversion. [rcemlearning.co.uk]
General Treatment Principles Treatment should be based on the ventricular rate, not the atrial rate Example: Atrial flutter with 4:1 or 5:1 with a ventricular rate of 30 should be treated as an bradydysrhythmia. [maryland.ccproject.com]
The treatment for all unstable patients is synchronized electrical cardioversion. Contact [aibolita.com]
Treatment Considerations – Sustained fascicular VT responds extremely well to treatment with IV verapamil ( proposed role for slow inward calcium channel in genesis of the arrhythmia ) — and this is the treatment of choice when the arrhythmia is recognized [ecg-interpretation.blogspot.com]
Prognosis
This arrhythmia is usually stable and the prognosis is much more favorable than VT. It is usually treated with vagal maneuvers or adenosine. What does aberrancy mean? You can think of “aberrancy” as abnormal conduction. [aclsmedicaltraining.com]
Prognosis Monomorphic VT usually occurs after myocardial infarction and is a sign of extensive myocardial damage; there is a high mortality, often resulting from impaired ventricular function. [patient.info]
VT is the most important differential diagnosis because of its unfavorable prognosis. An accurate diagnosis with immediate treatment is usually required. [e-arrhythmia.org]
The natural history of atrial fibrillation: Incidence, risk factors, and prognosis in the Manitoba Follow-Up Study. Am J Med 1995;98(5):476-484. Benjamin EJ, Levy D, Vaziri SM, et al. [ahcmedia.com]
Etiology
That said — IF there is any doubt about etiology — verapamil/diltiazem should not be given for WCT. [ecg-interpretation.blogspot.com]
Etiology: 1. Enhanced Automaticity 2. Triggered Activity: Early Afterdepolarization (EAD's) 3. [quizlet.com]
History of ischemic heart disease is consistent with ventricular issues The physical examination may or may not be helpful in determining a possible etiology for a patient's symptoms. [aafp.org]
Epidemiology
Common Types of Supraventricular Tachycardia and Usual Characteristics Type Epidemiology Mechanism Possible electrocardiography changes AVNRT Most common SVT (approximately 50 to60%) 4 Occurs more often in younger women Reentry caused by nodal pathways [aafp.org]
Sinus tachycardia, atrial fibrillation, atrial flutter, and multifocal atrial tachycardia are briefly discussed for purposes of recognition. 1-4 Epidemiology SVTs are estimated to have an incidence of 35 cases per 100,000 persons-years, with a two-fold [ahcmedia.com]
Pathophysiology
These tachycardias are diverse; as such, the pathophysiology behind each form of WCT includes toxic, metabolic, and conduction system dysfunction mechanisms. [ncbi.nlm.nih.gov]
In order to understand the visual differences between VT and SVT with aberrant conduction, one must first understand the basic pathophysiology behind the two dysrhythmias. [emsworld.com]
Pathophysiology A sudden change in the length of the previous cardiac cycle results in a refractory right or left bundle branch. Refractoriness in any bundle branch does not allow the supraventricular impulse to propagate in that branch. [metealpaslan.com]
35 per 100,000 person-years, with a prevalence of 2.29 per 1,000 persons. 7 Although AVNRT is the most common SVT in adults (approximately 50 to 60 percent), 4 AVRT is most common in children (accounts for approximately 30 percent of all SVTs). 4, 5 Pathophysiology [aafp.org]
Prevention
Preventing complications of adenosine administration. Ann Emerg Med 2002;39:347–8 PubMed CrossRef Google Scholar 8. Chang M, Wrenn K. Adenosine dose should be less when administered through a central line. [link.springer.com]
[…] therapy Verapamil IV: calcium channel blocker Prevents SVT 80 to 240 mg orally three times daily Adverse effects include constipation, dizziness Avoid in patients with Wolff-Parkinson-White syndrome or wide complex tachycardia Table 6. [aafp.org]
Presumably it will also respond to IV diltiazem — though the effectiveness of oral calcium blockers for preventing recurrence is variable. [ecg-interpretation.blogspot.com]
This cancellation prevents precipitation of a VT dysrhythmia. [emsworld.com]
Conduction through the AV node, corresponding to the PR interval on the ECG, is slow and serves as protection that prevents excessive ventricular stimulation from accelerated atrial rhythms. [ahcmedia.com]