Radiofrequency ablation of frequent, idiopathic premature ventricular complexes: comparison with a control group without intervention.

BACKGROUND

Idiopathic premature ventricular complexes (PVCs) usually are considered benign, even when frequent. However, case reports have demonstrated a possible link between frequent PVCs and left ventricular (LV) dysfunction. In addition, frequent PVCs recently were demonstrated to be associated with increased LV dimensions and cardiomyopathy.

METHODS

Among 60 consecutive patients with idiopathic, frequent PVCs (>10/hour), a reduced LV ejection fraction (EF; mean 34% +/- 13%) was present in 22 (37%) patients. Patients with decreased LV function had a greater PVC burden on a 24-hour Holter monitor than patients with normal EF (37% +/- 13% vs. 11% +/- 10% of all QRS complexes; P <.0001). There was a significant inverse correlation between the PVC burden and the EF before ablation (r = 0.73, P <.0001).

RESULTS

The PVCs originated in the right ventricular outflow tract in 31 (52%) of 60 patients, the LV outflow tract in 9 (15%) of 60 patients, and in other sites in 13 (22%) of 60 patients. The site of PVC origin could not be determined in seven patients. Ablation was completely successful in 48 (80%) patients. In patients with an abnormal EF before ablation, LV function normalized in 18 (82%) of 22 patients from a baseline of 34% to 59% +/- 7% (P <.0001) within 6 months. In the four patients in whom ablation was ineffective, the EF further declined from 34% +/- 10% to 25% +/- 7% (P = .06) during follow-up. In a control group of 11 patients with a similar PVC burden (30% +/- 8%) and a reduced EF (28% +/- 13%) who did not undergo ablation, the EF remained unchanged in 10/11 patients over 19 +/- 17 months of follow-up and one patient underwent heart transplantation.

CONCLUSION

LV dysfunction in the setting of frequent, idiopathic PVCs may represent a form of cardiomyopathy that can be reversed by catheter ablation of the PVCs.