Catheter-based interventions in the early post-operative period are performed with caution due to concerns for increased procedural risk, particularly across fresh suture lines. The recently published CRISP scoring system provides prospective risk stratification based on pre-procedural criterion. In an effort to refine the assessment of risk in patients undergoing post-operative catheter-based interventions, the predicted risk of an adverse event based on CRISP scores was compared to actual adverse event rates. A single-center, retrospective review of patients undergoing catheterization interventions within 6 weeks of cardiac surgery was conducted between Jan 2004 and Dec 2014. Patients who underwent dilation interventions across fresh suture lines (group 1) were compared to patients who underwent interventional procedures at other sites (group 2), and a CRISP score was calculated for all patients. Patients receiving only surveillance biopsies were excluded. Sixty-eight patients underwent 100 interventional procedures. Group 1 was composed of 44 patients receiving 64 interventions, while group 2 had 24 patients who underwent 36 interventions. Group 1 was comprised significantly more single ventricles and patients were smaller/younger. Group 1 had a significantly higher median CRISP score, but both groups were within Category 4. The rates of adverse events were similar between groups and comparable to predicted rates with the CRISP scoring system. Catheter-based interventions in the early post-operative period can be performed with no significant increase in the risk of serious adverse events when intervening across fresh suture lines. The CRISP scoring system can be a valuable tool in pre-procedural counseling of high-risk post-operative patients.