By Jessica Ross for Heart1
British Prime Minister Tony Blair joined the growing ranks of patients to benefit from cardiac catheterization on October 1. Blair, 51, had been previously diagnosed with supraventricular tachycardia (SVT), a heart condition characterized by rapid heartbeat localized above the ventricles (lower heart chambers). Using cardiac catheterization, physicians corrected the abnormality by destroying (ablating) the cells responsible for the SVT. In recent years this minimally invasive technique has been heralded as a highly successful method for treating several types of cardiac arrhythmia.
The process of cardiac catheterization (also referred to as cardiac catheter ablation, radiofrequency ablation, radiofrequency cardiac ablation, or cardiac ablation) first identifies and then eradicates the specific cardiac cells responsible for creating erratic electrical impulses,
or heartbeats. During the procedure, a long narrow wire (catheter) is threaded through a major blood vessel (vein or artery) in the groin or neck to the heart. Physicians are guided in this process by fluoroscopy, a continuous live imaging system similar to an X-ray.
Within the heart, tiny electrodes at the tip of the catheter then provide controlled electrical stimuli to cardiac cells, which allows physicians to pinpoint the exact cells responsible for the irregularity. Once these cells are identified, radiofrequency (RF) energy is delivered to the site, destroying the problematic cells. The use of RF energy generates a low-voltage, high-frequency electrical impulse that is highly precise and of relatively low risk for the patient. As an alternative to RF energy, cells can also be destroyed using intense cold or “cryoablation.” Once the “problem” cells removed, the heart is able to resume a normal pattern of electrical impulses/heartbeats.
With a success rate of over 95%, cardiac catheterization offers patients a clear option beyond the traditional medications, pacemakers, or surgery. Moreover, similarly to other types of “microsurgery,” recovery is relatively rapid. Patients are usually conscious during the procedure, merely requiring intravenous drugs rather than complete sedation. The entire process is completed in only a few hours, with patients able to return home the day after surgery. Side effects may include some reported discomfort, but rarely any significant pain.
Cardiac catheterization is often recommended for individuals diagnosed with tachycardia (rapid heartbeat) conditions including Atrial Fibrillation, Atrial Flutter, AV Nodal Reentrant Tachycardia (AVNRT), AV Reentrant Tachycardia (AVRT) and Atrial Tachycardia. Although the precise type of arrhythmia may vary, generally the irregularity must be consistent and possess only a limited number of sources for successful “mapping” of the problem cells. As well, the patient must have reasonable blood pressures. Significantly, recent work by Dr. George Van Hare of Seattle Children’s Hospital and Regional Medical Center has also shown the technique to be similarly successful and safe for use in children.
SOURCES
•Alexander, Mark E. “Arrhythmias in Congenital Heart Disease.” Adult Congenital Heart Association. December 9, 2003. www.achaheart.org •U.S. Food and Drug Administration. “Cardiac Ablation Catheter.” FDA Heart Health Online. February 27, 2004. www.fda.gov •National Institute of Health. “Radiofrequency ablation helps sick youth.” United Press International. October 1, 2004.www.nlm.nih.gov •Chun TU, Van Hare GF. “Advances in the approach to treatment of supraventricular tachycardia in the pediatric population.” Curr Cardiol Rep. 2004 Sep;6(5):322-6. •Heart Rhythm Society. Cardiac Ablation. www.hrspatients.com •American College of Cardiology. “Cardiac Arrhythmias” March 12, 2002. www.acc.org •Roberts, Michelle. “Will Blair bounce back from op?” BBC News. October 1, 2004. newsvote.bbc.co.uk •Chandrakantan A. et al. “Radiofrequency Catheter Ablation.” EMedicine. July 26, 2004. www.eMedicine.com •CNN. “Blair ‘fine’ after heart treatment.” October 1, 2004. www.CNN.com
