Emerging indications for permanent pacing.

New indications for pacing are being investigated in the areas of vasovagal syncope, hypertrophic obstructive cardiomyopathy, dilated cardiomyopathy, and atrial fibrillation. It is hoped that pacing will offer an alternative therapy to patients who are refractory to medical therapy. Although pacing for vasovagal syncope continues to be controversial, it appears that a highly symptomatic group with a predominately cardioinhibitory component can benefit. Current data indicate that dual-chamber pacing should not be considered therapeutically equal to septal myectomy in patients with hypertrophic obstructive cardiomyopathy, but may be considered in those more than 65 years of age, or in others who are not good surgical candidates. Biventricular or left ventricular pacing appears promising in heart failure patients and may be combined with implantable cardioverter-defibrillator therapy. Lead technology for coronary vein placement needs further improvement. Dual-site atrial pacing appears to help prevent recurrences of atrial fibrillation and may become a useful adjunct to drug, ablative, and implantable cardioverter-defibrillator therapies.