Off-pump Versus On-pump Coronary Artery Bypass Surgery: Graft Patency Assessment With Coronary Computed Tomographic Angiography: A Prospective Multicenter Randomized Controlled Pilot Study

Anterolateral territory coronary artery bypass grafting strategies: a non-inferiority randomized clinical trial: the AMI-PONT trial

OBJECTIVES

The main objective was to assess whether a composite coronary artery bypass grafting strategy including a saphenous vein graft bridge to distribute left internal mammary artery outflow provides non-inferior patency rates compared to conventional grafting surgery with separated left internal mammary artery to left anterior descending coronary graft and aorto-coronary saphenous vein grafts to other anterolateral targets.

METHODS

All patients underwent isolated grafting surgery with cardiopulmonary bypass and received ≥2 grafts/patients on the anterolateral territory. The graft patency (i.e. non-occluded) was assessed using multislice spiral computed tomography at 1 year.

RESULTS

From 2012 to 2021, 208 patients were randomized to a bridge (n = 105) or conventional grafting strategy (n = 103). Patient characteristics were comparable between groups. The anterolateral graft patency was non-inferior in the composite bridge compared to conventional grafting strategy at 1 year [risk difference 0.7% (90% confidence interval -4.8 to 6.2%)]. The graft patency to the left anterior descending coronary was no different between groups (P = 0.175). Intraoperatively, the bridge group required shorter vein length for anterolateral targets (P < 0.001) and exhibited greater Doppler flow in the mammary artery pedicle (P = 0.004). The composite outcome of death, myocardial infarction or target vessel reintervention at 30 days was no different (P = 0.164).

CONCLUSIONS

Anterolateral graft patency of the composite bridge grafting strategy is non-inferior to the conventional grafting strategy at 1 year. This novel grafting strategy is safe, efficient, associated with several advantages including better mammary artery flow and shorter vein requirement, and could be a valuable alternative to conventional grafting strategies. Ten-year clinical follow-up is underway.

TRIAL REGISTRATION

ClinicalTrials.gov: NCT01585285.

Angiographic Outcomes for Arterial and Venous Conduits Used in CABG

Coronary artery bypass grafting is the most commonly performed cardiac surgical procedure. Conduit selection is crucial to achieving early optimal outcomes, with graft patency being likely the main driver to long-term survival. We present a review of current evidence on the patency of arterial and venous bypass conduits and of differences in angiographic outcomes.

Conduit selection and early graft failure in coronary artery bypass surgery: A post hoc analysis of the Cardiovascular Outcomes for People Using Anticoagulation Strategies (COMPASS) coronary artery bypass grafting study

OBJECTIVES

Relative rates of early graft failure and conduit selection in coronary artery bypass grafting (CABG) surgery remain controversial. Therefore, we sought to determine the incidence and determinants of graft failure of the left internal mammary artery (LIMA), radial artery, saphenous vein, and right internal mammary artery (RIMA) 1 year after CABG surgery.

METHODS

A post hoc analysis of the Cardiovascular Outcomes for People Using Anticoagulation Strategies (COMPASS) CABG study, involving patients from 83 centers in 22 countries. We completed an analysis of 3480 grafts from 1068 patients who underwent CABG surgery with complete computed tomography angiography data. The primary outcome was graft failure as diagnosed by computed tomography angiography 1 year after surgery.

RESULTS

Graft failure occurred in 6.4% (68/1068) for LIMA, 9.9% (9/91) for radial artery, 10.4% (232/2239) for saphenous vein, and 26.8% (22/82) for RIMA grafts. The RIMA had a greater rate of graft failure (26.8%) than radial artery (9.9%) and veins (10.4%) (adjusted odds ratio, 2.69; 95% confidence interval, 1.30-5.57; P = .008 and adjusted odds ratio, 2.07; 95% confidence interval, 1.33-3.21; P = .001, respectively).

CONCLUSIONS

In this international trial dataset, LIMA and radial artery performed as expected, whereas vein grafts performed better. However, high rates of RIMA failure are worrisome and highlight the need for a thorough evaluation of the patency and safety of the RIMA in CABG surgery.

Randomized evidence on graft patency after off-pump versus on-pump coronary artery bypass grafting: An updated meta-analysis

BACKGROUND

The debate between off-pump CABG (OPCAB) and on-pump CABG (ONCAB) has been ongoing for decades. We aimed to provide a comprehensive update of the current randomized controlled trials (RCTs) in evaluating the graft patency of OPCAB versus ONCAB.

MATERIALS AND METHODS

A literature search was conducted in PubMed, EMBASE, and the Cochrane Library databases until April 30, 2021. All RCTs from 2003 to 2020 comparing the results of graft patency between OPCAB and ONCAB were included. We compared the overall graft occlusion between the two groups, and subgroup analyses were conducted based on different types of conduits and target territories, crossover from off-pump to on-pump rate, and the length of follow-up.

RESULTS

Sixteen RCTs were identified, with 5743 grafts in the OPCAB group and 5898 in the ONCAB group. OPCAB was associated with a higher risk of occlusion in the overall graft (RR: 1.31; 95% CI, 1.17-1.46), saphenous vein graft (SVG) (RR: 1.40; 95% CI, 1.23-1.59), grafts to left anterior descending (LAD) territory (RR: 1.52; 95% CI, 1.11-2.08) and left circumflex artery (LCX) territory (RR: 1.45; 95% CI, 1.19-1.76), while no significant difference was observed between the two groups in respect of arterial conduits and grafts to right coronary artery (RCA) territory. Furthermore, the lower crossover rate and longer length of follow-up appeared to reduce the association between OPCAB and lower graft patency.

CONCLUSIONS

The current meta-analysis indicates that, compared with ONCAB, graft patency is poorer with OPCAB for overall grafts, SVG grafts, grafts to LAD and LCX territories, whereas the results remain comparable for arterial conduits and grafts to RCA territory.

Development of a risk score for early saphenous vein graft failure: An individual patient data meta-analysis

OBJECTIVES

Early saphenous vein graft (SVG) occlusion is typically attributed to technical factors. We aimed at exploring clinical, anatomical, and operative factors associated with the risk of early SVG occlusion (within 12 months postsurgery).

METHODS

Published literature in MEDLINE was searched for studies reporting the incidence of early SVG occlusion. Individual patient data (IPD) on early SVG occlusion were used from the SAFINOUS-CABG Consortium. A derivation (n = 1492 patients) and validation (n = 372 patients) cohort were used for model training (with 10-fold cross-validation) and external validation respectively.

RESULTS

In aggregate data meta-analysis (48 studies, 41,530 SVGs) the pooled estimate for early SVG occlusion was 11%. The developed IPD model for early SVG occlusion, which included clinical, anatomical, and operative characteristics (age, sex, dyslipidemia, diabetes mellitus, smoking, serum creatinine, endoscopic vein harvesting, use of complex grafts, grafted target vessel, and number of SVGs), had good performance in the derivation (c-index = 0.744; 95% confidence interval [CI], 0.701-0.774) and validation cohort (c-index = 0.734; 95% CI, 0.659-0.809). Based on this model. we constructed a simplified 12-variable risk score system (SAFINOUS score) with good performance for early SVG occlusion (c-index = 0.700, 95% CI, 0.684-0.716).

CONCLUSIONS

From a large international IPD collaboration, we developed a novel risk score to assess the individualized risk for early SVG occlusion. The SAFINOUS risk score could be used to identify patients that are more likely to benefit from aggressive treatment strategies.

Rivaroxaban, Aspirin, or Both to Prevent Early Coronary Bypass Graft Occlusion: The COMPASS-CABG Study

BACKGROUND

Patients with recent coronary artery bypass graft (CABG) surgery are at risk for early graft failure, which is associated with a risk of myocardial infarction and death. In the COMPASS (Cardiovascular OutcoMes for People Using Anticoagulation StrategieS) trial, rivaroxaban 2.5 mg twice daily plus aspirin 100 mg once daily compared with aspirin 100 mg once daily reduced the primary major adverse cardiovascular events (MACE) outcome of cardiovascular death, stroke, or myocardial infarction. Rivaroxaban 5 mg twice daily alone did not significantly reduce MACE.

OBJECTIVES

This pre-planned substudy sought to determine whether the COMPASS treatments are more effective than aspirin alone for preventing graft failure and MACE after CABG surgery.

METHODS

The substudy randomized 1,448 COMPASS trial patients 4 to 14 days after CABG surgery to receive the combination of rivaroxaban plus aspirin, rivaroxaban alone, or aspirin alone. The primary outcome was graft failure, diagnosed by computed tomography angiogram 1 year after surgery.

RESULTS

The combination of rivaroxaban and aspirin and the regimen of rivaroxaban alone did not reduce the graft failure rates compared with aspirin alone (combination vs. aspirin: 113 [9.1%] vs. 91 [8.0%] failed grafts; odds ratio [OR]: 1.13; 95% confidence interval [CI]: 0.82 to 1.57; p = 0.45; rivaroxaban alone vs. aspirin: 92 [7.8%] vs. 92 [8.0%] failed grafts; OR: 0.95; 95% CI: 0.67 to 1.33; p = 0.75). Compared with aspirin, the combination was associated with fewer MACE (12 [2.4%] vs. 16 [3.5%]; hazard ratio [HR]: 0.69; 95% CI: 0.33 to 1.47; p = 0.34), whereas rivaroxaban alone was not (16 [3.3%] vs. 16 [3.5%]; HR: 0.99, CI: 0.50 to 1.99; p = 0.98). There was no fatal bleeding or tamponade within 30 days of randomization.

CONCLUSIONS

The combination of rivaroxaban 2.5 mg twice daily plus aspirin or rivaroxaban 5 mg twice daily alone compared with aspirin alone did not reduce graft failure in patients with recent CABG surgery, but the combination of rivaroxaban 2.5 mg twice daily plus aspirin was associated with similar reductions in MACE, as observed in the larger COMPASS trial. (Cardiovascular OutcoMes for People Using Anticoagulation StrategieS [COMPASS]; NCT01776424).

Mid- and long-term prognosis of off- vs. on-pump coronary artery bypass graft in patients with multisite artery disease

BACKGROUND

Among patients with coronary artery disease (CAD), around 25% have multisite artery disease (MSAD). Patients with CAD and MSAD are at higher risk of peri-operative and long-term cardiovascular events. Whether off-pump coronary bypass grafting (CABG) can improve their prognosis is unknown. We aimed to assess the benefits of off- vs. on-pump cardiac surgery in patients undergoing CABG, according to coexistence of extra-cardiac artery disease.

METHODS

Between April 1998 and September 2008, 1221 patients undergoing CABG without any other intervention were enrolled. Overall death and major cardiovascular events were recorded at 1-month and during long-term follow-up. A propensity score (PS), derived from all relevant variables (P<0.25) associated with on-pump as compared to off-pump CABG, and representing the likelihood for each individual patient to receive off-pump CABG, was calculated.

RESULTS

MSAD was observed in 279 patients (23%). Off-pump CABG was performed in 208 (17%) patients. The median follow-up was 7.6 years. The 10-year mortality was significantly lower in off- vs. on-pump CABG group (74±4% vs. 68±2%, P=0.024). In patients with MSAD, there was a trend for better survival for off- vs. on-pump CABG (63±8% vs. 50±4%, P=0.078). After adjustment for PS, we found no further difference between on- and off-pump CABG both in the whole cohort (HR=1.30, P=0.10), as well as in MSAD patients (HR=1.51, P=0.14).

CONCLUSIONS

Patients with MSAD receiving CABG are at worst prognostic than those with isolated CAD. In these patients, we found no significant difference in the long-term mortality and cardiovascular events between on- and off-pump CABG.

Incidental findings in CT imaging of coronary artery bypass grafts: results from a Canadian multicenter prospective cohort

Objective

To assess the prevalence and clinical significance of incidental findings identified during computed tomography imaging of coronary artery bypass grafts.

Results

This prospective study includes 144 patients undergoing coronary graft patency assessment using computed tomography. Incidental findings were classified as significant if they were considered to need an immediate action or treatment, short-term work-up or follow-up, or minor. A total of 211 incidental findings were present in 109 (75.7%) patients. Seventy-one incidental findings (33.6%) were cardiac and 140 (66.4%) were extracardiac. Most common cardiac incidental findings were atrial dilatation [39 patients, 48 incidental findings (67.6%)] and aortic valve calcifications (7 patients, 9.9%). Among the 140 extracardiac incidental findings, the most common were lung nodules (51 patients, 54 nodules, 38.6%), and emphysema (21 patients, 15%). Thirty-six (25.7%) extracardiac incidental findings were significant and notably, 23 (63.9%) were lung nodules. Follow-up was recommended in 37 cases, among which all patients with significant lung nodules (23 patients, 62.2%). In conclusion, most common computed tomography incidental findings in patients with coronary grafts were lung nodules and emphysema.

Electronic supplementary material

The online version of this article (10.1186/s13104-018-3168-1) contains supplementary material, which is available to authorized users.

The Role of Computed Tomographic Angiography in Predicting Left Anterior Descending Artery Graftability When Catheter Angiography is Inconclusive

PURPOSE

Graftability of the left anterior descending artery (LAD) has important prognostic value for coronary artery bypass graft (CABG) surgery. However, with a chronic total occlusion (CTO) of the LAD, invasive coronary angiography (ICA) may be insufficient to determine its graftability. We evaluated the role of coronary computed tomographic angiography (CTA) in the assessment of CTO and LAD graftability when the distal vessel segment was incompletely visualized by ICA.

MATERIALS AND METHODS

We enrolled 31 patients with equivocal eligibility for CABG due to CTO of the LAD with poor distal flow defined by ICA. Patients with LAD diameters ≥1.5 mm by CTA underwent CABG surgery, and the vessel diameter was reassessed intraoperatively.

RESULTS

The mean age was 54±14 years. Seven patients (23%) had suitable LAD targets on CTA and underwent successful CABG. Another 24 patients (77%) had nongraftable LADs. Patients with a graftable LAD showed no significant difference between mean LAD diameter measured by CTA and during surgery (1.6±0.3 vs. 1.5±0.3 mm, P=0.21). The preoperative left ventricular ejection fraction was not significantly different between groups (35%±8% vs. 35%±7%, P=0.2). However, after a mean follow-up of 21±7 months, left ventricular ejection fraction was significantly higher in vascularized patients (41%±5.8% vs. 34%±8%, P=0.01, respectively). Six of 7 patients had patent LAD grafts on CTA at 1-year follow-up.

CONCLUSION

CTA may provide valuable information about chronically occluded LAD size and graftability when ICA is inconclusive.