Radiofrequency catheter ablation and nerve growth factor concentration in humans

BackgroundIn animal models, expression of nerve growth factor (NGF) is increased after necrotic myocardial injury. Whether radiofrequency (RF) catheter ablation increases NGF expression in humans is unclear.ObjectivesThe purpose of this study was to determine NGF concentrations in the aorta, coronary sinus, and peripheral veins before and after RF ablation in patients.MethodsWe sampled blood from aorta and either great cardiac vein (group 1, N = 18) or proximal (group 2, N = 20) coronary sinus before and after RF ablation. In group 3 (N = 21), peripheral venous blood was sampled before and after RF ablation and then up to postoperative day 7. In group 4 (N = 10), we sampled peripheral venous blood during diagnostic electrophysiologic study. The NGF concentration was determined by enzyme-linked immunosorbent assay. Transcardiac NGF concentration was the difference in NGF concentrations between coronary sinus and aorta.ResultsThere was no change in transcardiac NGF concentrations in groups 1 and 2. In group 3, the NGF level did not change significantly from before the procedure (17.10 ± 15.80 ng/mL) to immediately after the procedure (14.46 ± 10.36 ng/mL). However, NGF levels increased significantly to 31.24 ± 19.82 ng/mL (N = 21, P <.0001) on postoperative day 1, 26.23 ± 16.89 ng/mL (N = 20, P <.001) on postoperative day 2, and 22.01 ± 11.35 ng/mL (N = 16, P = .003) on postoperative day 3. NGF concentrations did not change significantly in group 4.ConclusionRF ablation did not result in a detectable increase of transcardiac NGF concentration immediately after the procedure. However, the systemic NGF concentration increased significantly on postoperative days 1 to 3, suggesting that RF ablation resulted in increased NGF expression.