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Published on: March 27, 2018
Impact of Diagonal Branch Angle on Cardiac Outcomes After Sequential Coronary Bypass Surgery
Akinobu Ohtani1, Shin Yajima1, Daisuke Yoshioka1
1Department of Cardiovascular Surgery, The University of Osaka, Suita, Osaka 565-0871, Japan.
Insights
A narrow diagonal branch anastomotic angle (D-angle) during coronary artery bypass grafting (CABG) is linked to more adverse sequential graft events. This finding highlights the importance of graft angle in CABG outcomes.
Area of Science:
- Cardiovascular Surgery
- Vascular Anastomosis
- Graft Patency
Background:
- Coronary artery bypass grafting (CABG) is a critical revascularization procedure.
- Graft selection and configuration significantly impact long-term outcomes.
- The anatomical relationship of sequential grafts, specifically the diagonal branch anastomotic angle (D-angle), has not been extensively studied.
Purpose of the Study:
- To investigate the association between the diagonal branch anastomotic angle (D-angle) and clinical outcomes after CABG.
- To determine if a narrow D-angle is a risk factor for adverse events in patients receiving sequential grafts.
Main Methods:
- Retrospective analysis of 197 patients undergoing isolated CABG with specific sequential grafting techniques (LITA-LAD and RITA-RA).
- Patients were categorized into 'Narrow' (D-angle ≤ 90°) and 'Wide' (D-angle > 90°) groups.
- Clinical outcomes, including mortality and graft-related events, were assessed over a median follow-up of 5.7 years.
Main Results:
- No significant differences in all-cause mortality or general adverse cardiac events between groups.
- Patients with a narrow D-angle experienced significantly lower freedom from adverse sequential graft events (74% vs. 92% at 5 years).
- A narrow D-angle was identified as an independent predictor of adverse sequential graft events (aHR 4.3, P=0.014).
Conclusions:
- A narrow D-angle is independently associated with an increased risk of adverse sequential graft events after CABG.
- Optimizing the D-angle may be crucial for improving the long-term patency and success of sequential grafts in CABG surgery.
Objectives:
To evaluate whether the diagonal branch anastomotic angle (D-angle) influences outcomes following coronary artery bypass grafting (CABG).
Methods:
This study retrospectively examined 197 patients who underwent isolated CABG between 2010 and 2023 using left internal thoracic artery (LITA)-left anterior descending artery (LAD) grafting and clockwise right ITA (RITA)-radial artery (RA) I-composite sequential grafts. Patients were categorized into Narrow (D-angle ≤ 90°, n = 16) and Wide (D-angle > 90° or without diagonal anastomosis, n = 181) groups.
Results:
Mean age was 69 ± 10 and 65 ± 10 years in the Narrow and Wide groups, respectively (P = .107). Male sex (93.8% vs 91.2%), diabetes (68.8% vs 57.5%), 3-vessel disease (75.0% vs 85.1%), and off-pump CABG (68.8% vs 76.2%) values were similar; however, the Narrow group had more anastomoses (4.2 ± 0.8 vs 3.4 ± 0.7, P < .001). Median follow-up was 5.7 years [3.2-9.1]. Rates of all-cause mortality and adverse cardiac events did not differ significantly (P = .193; P = .074). However, freedom from adverse sequential graft events was lower in the Narrow group, with 1-, 5-, and 10-year estimates of 74.0%, 74.0%, and 74.0%, compared with 93.6%, 92.0%, and 92.0% in the Wide group, respectively (log-rank P = .008). Narrow D-angle remained an independent predictor in multivariate analysis (adjusted hazard ratio, 4.3; 95% confidence interval, 1.3-13.7; P = .014).
Conclusions:
A narrow D-angle was independently associated with increased incidence of adverse sequential graft events.
