| New approaches are steadily emerging in the fast-paced progress of cardiologic technology to treat arrhythmias refractory to medical management. Recently developed methods of ablation include ultrasound ablation and cryoablation, devices related to which have now gained FDA approval. These innovations show much promise for complex arrhythmias such as ventricular tachycardia and ischemic cardiomyopathy, where radiofrequency (RF) catheter ablation can entail the creation of large lesions and the use of relatively high temperature levels, often resulting in heat-related collateral damage, such as pulmonary vein stenosis, clots and stroke.
Nonetheless the “gold standard” technique remains RF ablation, now available for nearly 15 years, during which it has proven to be a safe and reliable therapy to address a broad range of cardiac rhythm disturbances with a success rate greater than 90 percent. RF ablation can also resolve arrhythmias caused by bypass tracts (such as Wolff-Parkinson-White) in more than 95 percent of cases. Similar success rates have been demonstrated for an AV node arrhythmia called atrioventricular nodal reentrant tachycardia (AVNRT). RF ablation is also successful in about 95 percent of cases of atrial flutter.
Even in treating ventricular tachycardias, RF is effective in some people—especially those without underlying heart disease and with specific types of ventricular tachycardia (for example, bundle branch reentrant VT or right ventricular outflow tract VT). Success can be expected in almost 90 percent of these cases.
However, a study by German cardiologist Nikolaos Dagres, which appeared in the September 17, 2003 issue of the Journal of the American College of Cardiology, indicates that women with heart arrhythmias are referred for RF catheter ablation therapy significantly later than male patients. The paper reported that women with the same or more severe symptoms as men were referred an average of 28 months later than men for RF ablation treatment.
The study author and his colleagues reviewed 894 patients, 418 men and 476 women, who had the treatment at the Hospital of the Westfaelische Wilhelms-University during a 43-month period. In addition to being referred later, women patients had been given more anti-arrhythmic drugs and at the time of referral, women were more symptomatic with a higher number of patients (80 percent of women compared to 70 percent of men) experiencing frequent tachycardia episodes, more than once a month.
Gender did not affect the procedure’s success (93 percent for the men and 95 percent for the women); significant complication rates (1.1 percent for both men and women); or recurrence rates (10 percent for men and 7.3 percent for women). No procedure-related deaths occurred in either group.
Dr. Dagres said that the study cannot explain why women were referred later than men to ablation treatment. Plausible explanations, he said, could include a higher tolerance of symptoms among women than men; procrastination owing to child care concerns or other issues; the dismissal by physicians of supraventricular tachycardia in women as panic attacks; or, in some cases, physicians may be more likely to dismiss the symptoms of women. Other studies have also observed a general tendency for women to be referred later to a variety of medical treatments, but he noted there is no medical reason for delaying ablation therapy. |
