Physical examination in the diagnosis of SVT may or may not be helpful in determining the etiology of the presenting symptoms. Younger, presumably healthy individuals usually have normal findings during physical examination with a single abnormal finding of tachycardia.1
WORKUP OF SVT The focused exam should include the cardiovascular, respiratory, and endocrine systems. During the cardiovascular exam, a practitioner should auscultate carefully for murmur(s), friction rub, third heart sound, and cannon waves. These findings are significant in the diagnosis of valvular heart disease, pericarditis, heart failure, and specific types of tachycardia, which is the culprit for arrhythmias and other symptoms. A respiratory exam could reveal crackles that would lead to the diagnosis of heart failure as the precipitant of tachycardia. An endocrine exam will pinpoint or rule out hyperthyroidism or thyroiditis as the cause of tachycardia.1 The diagnostic workup office visit should include vitals, orthostatic blood pressure, blood work (complete blood count, thyroid stimulating hormone, basic metabolic panel, brain natriuretic peptide, and cardiac enzymes), and diagnostics (chest X-ray, Holter monitor or event recorder, graded exercise testing, and echocardiography [12 lead]).1 The EKG will determine if pre-excitation is present to differentiate AVRT from other causes of and types of tachycardia. Figure 1 shows how the diagnostic workup of a patient with suspected SVT should be performed.
synchronized cardioversion is the treatment of choice.13 Long-term management distinguishes the SVT type, frequency and intensity, risk of therapy, and overall impact on the life of the patient.9 Options for long-term management include cardiac ablation and pharmacologic treatments.1 The most common method of cardiac ablation is radiofrequency (RF) in which an electrode is threaded through a vein or artery into the heart where it coagulates the abnormal tissue. This procedure forms a scar to prevent the targeted area of the heart from preexcitation, permanently in most situations.10 Pharmacologic treatments for long-term management include beta blockers, diltiazem or verapamil, flecainide or propafenone, amiodarone/ dofetilide or sotalol, and digoxin.13 Some practitioners have adopted a “pill-in-the-pocket” method of long-term management. “Pill-in-the-pocket” methodology has been adopted for patients with infrequent episodes or for those in need of intermittent treatment.11 This patient demographic is advised to keep prescribed medication in her pocket at all times reserved for an episodic occurrence.
TREATMENT OF SVT Prior Symptoms
SVT treatment focuses on the cessation of active episodes. In individuals with frequent episodes and serious symptoms (pre-syncope and syncope), cessation is critical. Treatment is divided into short-term and long-term management.1 Short-term or urgent treatment may include the use of oral or intravenous antiarrhythmic drug therapy, vagal maneuvers, and electrical cardioversion for SVT.8 According to JAMA Cardiology and the 2015 ACC/AHA/HRS Guideline for the Management of Adult Patients With Supraventricular Tachycardia, initial treatment should begin with vagal maneuvers and/or adenosine.13 If the patient is hemodynamically stable, pharmacologic treatment (beta blockers, diltiazem, or verapamil) should be administered intravenously for immediate relief.13 If a patient is found to be hemodynamically unstable or pharmacologic intervention is not feasible,
Presenting Symptoms
Pre-excitation
Irregular Rate
Regular Rate
Adapted from Page et al.13
FIGURE 1. Diagnostic workup of a patient with possible supraventricular tachycardia
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