SVT Abalation

Supraventricular tachycardia (SVT) is a condition characterized by rapid heartbeats that originate in the upper chamber of the heart. The focus of this arrhythmia usually is electrical fibers that are sending electrical impulses at rates faster or slower than usual. In many cases, patients can have rapid onset and cessation of the arrhythmia. The symptoms associated with SVT are a rapid or racing pulse, dizziness, lightheadedness, difficulty breathing and, in some cases, chest pains.
The treatment of SVT during the acute presentation is the administration of adenosine. This medication blocks impulses to the electrical switch in between the upper and lower chambers of the heart and allows the heart to reset to a normal rate. In cases of extremely low blood pressure, an electrical shock may be needed to convert the heart rate back to normal.
The long-term management of SVT includes medications such as beta-blockers, calcium channel blockers and occasionally cardiac glycosides (digoxin). The use of more potent anti-arrhythmics can be considered for cases unresponsive to the usual medical therapy. Unfortunately, most patients with SVT are relatively young. The side effects associated with long-term use of anti-arrhythmics can be dangerous and non-reversible in many cases . The treatment of choice in the management of recurrent SVT is catheter ablation.
In patients with SVT, the insertion of a catheter into the venous system via the leg or neck veins can easily treat many types of SVT. In particular, SVT that originates on the right side of the heart can be eradicated safely and effectively. While using mild sedation, the physician will identify the focus of the SVT and induce it. The catheter then delivers radiofrequency energy to the tissue to close the re-entry circuit and stop the SVT. If the focus of the SVT is left-sided, a trans-septal puncture may be needed (needle puncture of the atrial septum). This adds more risk to the procedure. After the ablation, the physician will then attempt to induce the SVT again. A second or even third focus of SVT often will present itself, which the physician can then ablate. After ablation, some additional medical therapy will be necessary, but in the majority of SVT cases the procedure is curative.
SVT ablation is a relatively low-risk procedure. The most common complication is at the access site (often the groin) and can be major bleeding or hematoma. Bleeding can be severe enough to require a transfusion in rare cases. Rare but serious complications include cardiac perforation and complete heart block requiring a permanent pacemaker. The risk of complete heart block increases as the focus of the SVT is closer to the heart's conduction system.
In the vast majority of ablation cases, the results are highly effective and durable. This makes it the treatment of choice in arrhythmias that can be accessed from the right side of the heart in many patients.