Learning Curve of Robotic Percutaneous Coronary Intervention: A Single-Center Experience

Robotic percutaneous coronary intervention (R-PCI) has been shown to provide benefits to operators and patients when compared with traditional percutaneous coronary intervention. Despite being available for 16 years in the United States, utilization of R-PCI remains low. This may be because of an expected learning curve with this technology. We sought to describe the characteristics and magnitude of the learning curve with R-PCI.

Consecutive patients undergoing R-PCI (Corpath GRX-2) at a tertiary care center by a single operator were studied prospectively. Demographic, angiographic, and procedural variables were collected. The primary study endpoints included fluoroscopy time, procedure time, and contrast volume. The distributions of each of these variables were plotted against the case numbers in chronological sequence, and the best curve fits were identified. Using the best model, the slope of the relationships was analyzed. Flattening of the slope of these plots were considered suggestive of a learning effect.

A total of 546 R-PCI and 1654 traditional percutaneous coronary intervention procedures were studied; 22 crossovers to traditional percutaneous coronary intervention occurred. Most of the crossovers occurred in the first quartile of procedures; no crossovers occurred in the latter half of the cohort. Procedure time decreased as the procedure number increased, with the slope flattening at procedure number 50. Contrast volume decreased as experience increased, with a slope flattening at procedure number 30. Both parameters continued to decrease as experience increased. Fluoroscopy time demonstrated a flattening slope after procedure number 15. This likely is driven by the lower complexity by Synergy between Percutaneous Coronary Intervention with Taxus and Cardiac Surgery (SYNTAX) score remained stable over the procedure sequence, with no significant complexity change over the study period.

The "learning effect" of R-PCI is observed with steep improvement in study metrics up to 50 procedures and a continuing improvement of lesser magnitude afterward.