Related Experiment Video
Updated: Jun 20, 2026
Optocardiography and Electrophysiology Studies of Ex Vivo Langendorff-perfused Hearts
Published on: November 7, 2019
Clinical and technical determinants of long-term performance of coronary sinus leads
Vincenzo La Rocca1, Emanuele Bertaglia, Francesco Solimene
1Casa di Cura San Michele, Maddaloni (CE), Italy.
Insights
Long-term follow-up of coronary sinus leads shows decreased pacing impedance and R-wave amplitude. Posterior lead placement and unipolar leads predict higher stimulation energy thresholds in cardiac resynchronization therapy.
Area of Science:
- Cardiology
- Biomedical Engineering
- Medical Device Technology
Background:
- Coronary sinus (CS) lead performance is critical for cardiac resynchronization therapy (CRT) but not well understood.
- Long-term device function depends on stable lead parameters.
Purpose of the Study:
- To evaluate the long-term performance of coronary sinus leads used in CRT.
- To identify clinical and technical factors influencing CS lead performance over time.
Main Methods:
- A cohort of 235 patients received CRT devices (pacemaker or defibrillator) between 1999 and 2004.
- Patients had a mean age of 68 years, mean LVEF of 26.5%, and various cardiomyopathy causes (idiopathic, ischemic).
- Coronary sinus lead parameters (impedance, R-wave amplitude, energy threshold) were monitored over a mean follow-up of 41.7 months.
Main Results:
- Mean pacing impedance decreased significantly from implantation to follow-up (811 to 717 Ω).
- Mean R-wave amplitude also decreased significantly (13.2 to 10.5 mV).
- Mean pacing energy threshold increased significantly (3.6 to 9.5 μJ), with unipolar leads and posterior CS lead position associated with higher increases.
- Posterior CS lead position was an independent predictor of increased stimulation energy threshold.
Conclusions:
- Coronary sinus lead performance in CRT patients is characterized by decreasing impedance and R-wave amplitude, and increasing energy threshold over the long term.
- Posterior lead placement within the coronary sinus is a significant predictor of increased stimulation energy threshold, impacting long-term CRT efficacy.
Objectives:
Little is known about coronary sinus lead performance in patients with cardiac resynchronization therapy devices. We evaluated the impact of clinical and technical parameters on coronary sinus lead performance over long-term follow-up.
Methods:
From February 1999 to July 2004, 235 patients (181 men; mean age, 68 +/- 9 years; mean left ventricular ejection fraction, 26.5 +/- 6.5%; idiopathic dilated cardiomyopathy, 49%; ischemic, 48%; and other cause, 3%) underwent cardiac resynchronization therapy (pacemaker or defibrillator) implantation.
Results:
On implantation, the only statistically significant difference was observed in mean pacing impedance, which was lower for unipolar leads than for bipolar leads (763 +/- 250 vs. 847 +/- 270 Omega, P = 0.02), and lower in patients with ischemic cardiomyopathy than in those with idiopathic cardiomyopathy (758 +/- 204 vs. 837 +/- 291 Omega, P = 0.03). After a mean follow-up of 41.7 +/- 14.7 months, a significant decrease was observed in mean pacing impedance (from 811 +/- 261 to 717 +/- 284 Omega, P = 0.0026) and mean R-wave amplitude (from 13.2 +/- 6.7 to 10.5 +/- 5.5 mV, P = 0.002), whereas the mean pacing energy threshold increased from 3.6 +/- 10.4 to 9.5 +/- 28 microJ (P = 0.004). On analysis of variance, unipolar lead (P = 0.016) and posterior coronary sinus position (P = 0.049) were related to a greater energy threshold increase. On multivariate analysis (Cox regression), only posterior coronary sinus lead position (P = 0.013) proved to be an independent predictor of long-term significant increase in the stimulation energy threshold.
Conclusion:
Over the long-term follow-up of coronary sinus leads, pacing impedance and R-wave amplitude decreased, whereas the energy threshold increased; unipolar leads and posterior lead location in the coronary sinus were related to a greater energy threshold increase.
