Supraventricular tachycardia paroxysmal

Compare and contrast the risk factors for and the features, mechanisms, etiologies, symptoms, and goals of therapy of (1) sinus bradycardia (2) atrioventricular (AV) nodal blockade (3) atrial fibrillation (AF) (4) paroxysmal supraventricular tachycardia (PSVT) ... 

Adenosine is the drug of choice for termination of paroxysmal supraventricular tachycardia. 

Paroxysmal supraventricular tachycardia (PSVT) is a term that refers to a number of arrhythmias that occur above the ventricles and that require atrial or AV nodal tissue for initiation and maintenance.32 The most common of these arrhythmias is... 

O Paroxysmal supraventricular tachycardia is caused by reentry that includes the AV node as a part of the reentrant circuit. Typically, electrical impulses travel forward (antegrade) down the AV node and then travel back up the AV node (retrograde) in a repetitive circuit. In some patients, the retrograde conduction pathway of the reentrant circuit may exist in extra-AV nodal tissue adjacent to the AV node. One of these pathways usually conducts impulses rapidly, while the other usually conducts impulses slowly. Most commonly, during PSVT the impulse conducts antegrade through the slow... 

TABLE 6-9. Drugs for Termination of Paroxysmal Supraventricular Tachycardia... 

FIGURE 6-10. Decision algorithm for termination of paroxysmal supraventricular tachycardia. HF, heart failure LVEF, left ventricular ejection fraction PSVT, paroxysmal supraventricular tachycardia. (Algorithm adapted with permission from Tisdale JE, Moser LR. Tachyarrhythmias. In Mueller BA, Bertch KE,... 

PST Paroxysmal supraventricular tachycardia S3 Third heart sound (ventricular gallop)... 

PSVT Paroxysmal supraventricular tachycardia S4 Fourth heart sound (atrial gallop)... 

Common supraventricular tachycardias requiring drug treatment are atrial fibrillation (AF) or atrial flutter, paroxysmal supraventricular tachycardia (PSVT), and automatic atrial tachycardias. Other common supraventricular arrhythmias that usually do not require drug therapy are not discussed in this chapter (e.g., premature atrial complexes, wandering atrial pacemaker, sinus arrhythmia, sinus tachycardia). 

AF, atrial fibrillation HF, heart failure 10, intraosseous PSVT, paroxysmal supraventricular tachycardia VF, ventricular fibrillation VT, ventricular tachycardia. 

FIGURE 6-2. Algorithm for the treatment of acute (top portion) paroxysmal supraventricular tachycardia and chronic prevention of recurrences (bottom portion). Note For empiric bridge therapy prior to radiofrequency ablation procedures, calcium channel blockers (or other atrioventricular [AV] nodal blockers) should not be used if the patient has AV reentry with an accessory pathway. (AAD, antiarrhythmic drugs AF, atrial fibrillation AP, accessory pathway AVN, atrioventricular nodal AVNRT, atrioventricular nodal reentrant tachycardia AVRT, atrioventricular reentrant tachycardia DCC, direct-current cardioversion ECG, electrocardiographic monitoring EPS, electrophysiologic studies PRN, as needed VT, ventricular tachycardia.)... 

Phenylephrine is used in hypotension, paroxysmal supraventricular tachycardia, and shock. It is also used locally, particularly in the form of nasal spray, for relieving edema. Synonyms of this dmg are ahnefrine, degest, neoxedrin, metaoxedrin, and many others. 

Verapamil is used for preventing angina pectoris attacks, arterial hypertension, and treating and preventing supraventricular arrhythmia (paroxysmal supraventricular tachycardia, atrial fibrillation, atrial flutter, extrasystole). Synonyms of this drug are isoptin, calan, fmoptin, falicard, manidone, and many others. 

Paroxysmal supraventricular tachycardias - 400 to 600 mg every 2 or 3 hours until the paroxysm is terminated. 

Atrial fibrillation For the prevention of paroxysmal atrial fibrillation/flutter (PAF) associated with disabling symptoms and paroxysmal supraventricular tachycardias (PSVT), including atrioventricular nodal reentrant tachycardia, atrioventricular reentrant tachycardia, and other supraventricular tachycardias of unspecified mechanism associated with disabling symptoms in patients without structural heart disease. 

PRN as needed (Latin pro re nata ) PSVT paroxysmal supraventricular tachycardia pt patient... 

Adenosine reduces heart rate and AV conduction, although it is not a calcium antagonist. It is administered intravenously for the acute treatment of paroxysmal supraventricular tachycardia. Adenosine displays a rapid onset and short duration of action. Apart from its antiarrhythmic activity it is also a vasodilator, in particular in the coronary system. 

Diltiazem Paroxysmal supraventricular tachycardia Atrial fibrillation... 

The prominent depressant action of verapamil and diltiazem at the SA and A-V nodes finds use in specific arrhythmias. They are of proven efficacy in acute control and long-term management of paroxysmal supraventricular tachycardia (see Chapter 16).Their ability to inhibit conduction at the A-V node is employed in protecting ventricles from atrial tachyarrhythmias, often in combination with digitalis or propranolol. 

Unlabeled Uses Control of hemodynamicallystableventriculartachycardia, control of rapid ventricular rate due to accessory pathway conduction in preexcited atrial arrhythmias, conversion of atrial fibrillation to normal sinus rhythm, in cardiac arrest with persistent ventricular tachycardia or ventricular fibrillation, paroxysmal supraventricular tachycardia, polymorphic ventricular tachycardia or wide complex tachycardia of uncertain origin, prevention of postoperative atrial fibrillation... 

Temporary control of rapid ventricular rate in atrial flBrillation or flutter, rapid conversion of paroxysmal supraventricular tachycardia to normal sinus rhythm IV push Initially, 0.25 mg/kg actual body weight over 2 min. May repeat in 15 min at dose of 0.35 mg/kg actual body weight. Subsequent doses individualized. IV Infusion / fter initial bolus injection, may begin infusion at 5-10 mg/hr may increase by 5 mg/hr up to a maximum of 15 mg/hr. Infusion duration should not exceed 24 hr. 

Paroxysmal supraventricular tachycardia (PSVT) The initial dose, given by rapid IV... 

Arrhythmias, including prevention of recurrent paroxysmal supraventricular tachycardia and control of ventricular resting rate in chronic atrial fibrillation or flutter (with di-goxin) PO 240-480 mg/day in 3-4 divided doses. 

It is a vasopressor agent with some structural similarity to adrenaline and has a powerful alpha receptor stimulant action. The pressor response is accompanied by reflex bradycardia. It is used as a nasal decongestant and mydriatic agent and also in the treatment of paroxysmal supraventricular tachycardia. 

It is effective orally and resistant to pseudo-cholinesterase and possesses longer duration of action. Its nicotinic action is less than acetylcholine and actions are more marked on CVS as compared to GIT and urinary system. Earlier it was used for CVS disorders such as peripheral vascular disease and paroxysmal supraventricular tachycardia. But now, it is rarely used in therapeutics. 

SA node Digitalis sensitizes the SA node to normal vagal impulse resulting in bradycardia. In a patient suffering from paroxysmal supraventricular tachycardia, it decreases the heart rate due to vagal action on SA node which is associated with decrease in the slope of slow diastolic depolarisation and increase in the transmembrane negativity and, also lower the SA rate by antiadrenergic action. 

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