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Background There remains uncertainty regarding the second‐best conduit after the internal thoracic artery in coronary artery bypass grafting. Few studies directly compared the clinical results of the radial artery ( RA ), right internal thoracic artery ( RITA ), and saphenous vein ( SV ). No network meta‐analysis has compared these 3 strategies. Methods and Results MEDLINE and EMBASE were searched for adjusted observational studies and randomized controlled trials comparing the RA , SV , and/or RITA as the second conduit for coronary artery bypass grafting. The primary end point was all‐cause long‐term mortality. Secondary end points were operative mortality, perioperative stroke, perioperative myocardial infarction, and deep sternal wound infection ( DSWI ). Pairwise and network meta‐analyses were performed. A total of 149 902 patients (4 randomized, 31 observational studies) were included ( RA , 16 201, SV , 112 018, RITA, 21 683). At NMA , the use of SV was associated with higher long‐term mortality compared with the RA (incidence rate ratio, 1.23; 95% CI , 1.12–1.34) and RITA (incidence rate ratio, 1.26; 95% CI , 1.17–1.35). The risk of DSWI for SV was similar to RA but lower than RITA (odds ratio, 0.71; 95% CI , 0.55–0.91). There were no differences for any outcome between RITA and RA , although DSWI trended higher with RITA (odds ratio, 1.39; 95% CI , 0.92–2.1). The risk of DSWI in bilateral internal thoracic artery studies was higher when the skeletonization technique was not used. Conclusions The use of the RA or the RITA is associated with a similar and statistically significant long‐term clinical benefit compared with the SV . There are no differences in operative risk or complications between the 2 arterial conduits, but DSWI remains a concern with bilateral ITA when skeletonization is not used.

IMPORTANCE Randomized clinical trials (RCTs) provide the highest level of evidence to evaluate 2 or more surgical interventions. Surgical RCTs, however, face unique challenges in design and implementation. OBJECTIVE To evaluate the design, conduct, and reporting of contemporary surgical RCTs. EVIDENCE REVIEW A literature search performed in the 2 journals with the highest impact factor in general medicine as well as 6 key surgical specialties was conducted to identify RCTs published between 2008 and 2020. All RCTs describing a surgical intervention in both experimental and control arms were included. The quality of included data was assessed by establishing an a priori protocol containing all the details to extract. Trial characteristics, fragility index, risk of bias (Cochrane Risk of Bias 2 Tool), pragmatism (Pragmatic Explanatory Continuum Indicator Summary 2 [PRECIS-2]), and reporting bias were assessed. FINDINGS A total of 388 trials were identified. Of them, 242 (62.4%) were registered; discrepancies with the published protocol were identified in 81 (33.5%). Most trials used superiority design (329 [84.8%]), and intention-to-treat as primary analysis (221 [56.9%]) and were designed to detect a large treatment effect (50.0%; interquartile range [IQR], 24.7%-63.3%). Only 123 trials (31.7%) used major clinical events as the primary outcome. Most trials (303 [78.1%]) did not control for surgeon experience; only 17 trials (4.4%) assessed the quality of the intervention. The median sample size was 122 patients (IQR, 70-245 patients). The median follow-up was 24 months (IQR, 12.0-32.0 months). Most trials (211 [54.4%]) had some concern of bias and 91 (23.5%) had high risk of bias. The mean (SD) PRECIS-2 score was 3.52 (0.65) and increased significantly over the study period. Most trials (212 [54.6%]) reported a neutral result; reporting bias was identified in 109 of 211 (51.7%). The median fragility index was 3.0 (IQR, 1.0-6.0). Multiplicity was detected in 175 trials (45.1%), and only 35 (20.0%) adjusted for multiple comparisons. CONCLUSIONS AND RELEVANCEIn this systematic review, the size of contemporary surgical trials was small and the focus was on minor clinical events. Trial registration remained suboptimal and discrepancies with the published protocol and reporting bias were frequent. Few trials controlled for surgeon experience or assessed the quality of the intervention.

In terms of in-hospital outcomes, controversy still remains whether off-pump coronary artery bypass grafting is superior to on-pump coronary artery bypass surgery. We investigated whether the volume of off-pump coronary artery bypass procedures by hospital and individual surgeon influences patient outcomes when compared with on-pump coronary artery bypass surgery. Discharge records from the Nationwide Inpatient Sample were retrospectively reviewed for in-hospital admissions from 2003 to 2011, including 999 hospitals in 44 states. A total of 2,094,094 patients undergoing on- and off-pump coronary artery bypass surgery were included. In patients requiring 2 or more grafts, off-pump coronary artery bypass compared with on-pump coronary artery bypass was associated with increased risk-adjusted mortality when performed in low-volume centers (<29 cases per year) (odds ratio [OR] 1.32, 95% confidence interval [CI] 1.06 to 1.57) or by low-volume surgeons (<19 cases per year) (OR 1.26, 95% CI 1.02 to 1.56). In high-volume off-pump coronary artery bypass centers (≥164 cases per year) and surgeons (≥48 cases per year), off-pump coronary artery bypass reduced mortality compared with on-pump coronary artery bypass in cases requiring a single graft (OR 0.66, 95% CI 0.49 to 0.89 and OR 0.33, 95% CI 0.22 to 0.47, respectively) or 2 or more grafts (OR 0.82, 95% CI 0.66 to 0.99 and OR 0.63, 95% CI 0.49 to 0.81, respectively). In conclusion, the outcome of off-pump coronary artery bypass grafting procedures is dependent on volume at both the institution and the individual surgeon level. Off-pump coronary artery bypass should not be performed at low-volume centers and by low-volume surgeons.

IMPORTANCEThe role of ticagrelor with or without aspirin after coronary artery bypass graft surgery remains unclear.OBJECTIVE To compare the risks of vein graft failure and bleeding associated with ticagrelor dual antiplatelet therapy (DAPT) or ticagrelor monotherapy vs aspirin among patients undergoing coronary artery bypass graft surgery.DATA SOURCES MEDLINE, Embase, and Cochrane Library databases from inception to June 1, 2022, without language restriction. STUDY SELECTION Randomized clinical trials (RCTs) comparing the effects of ticagrelor DAPT or ticagrelor monotherapy vs aspirin on saphenous vein graft failure.DATA EXTRACTION AND SYNTHESIS Individual patient data provided by each trial were synthesized into a combined data set for independent analysis. Multilevel logistic regression models were used. MAIN OUTCOMES AND MEASURESThe primary analysis assessed the incidence of saphenous vein graft failure per graft (primary outcome) in RCTs comparing ticagrelor DAPT with aspirin. Secondary outcomes were saphenous vein graft failure per patient and Bleeding Academic Research Consortium (BARC) type 2, 3, or 5 bleeding events. A supplementary analysis included RCTs comparing ticagrelor monotherapy with aspirin.RESULTS A total of 4 RCTs were included in the meta-analysis, involving 1316 patients and 1668 saphenous vein grafts. Of the 871 patients in the primary analysis, 435 received ticagrelor DAPT (median age, 67 years [IQR, 60-72 years]; 65 women [14.9%]; 370 men [85.1%]) and 436 received aspirin (median age, 66 years [IQR,[61][62][63][64][65][66][67][68][69][70][71][72][73]; 63 women [14.5%]; 373 men [85.5%]). Ticagrelor DAPT was associated with a significantly lower incidence of saphenous vein graft failure (11.2%) per graft than was aspirin (20%; difference, −8.7% [95% CI, −13.5% to −3.9%]; OR, 0.51 [95% CI, 0.35 to 0.74]; P < .001) and was associated with a significantly lower incidence of saphenous vein graft failure per patient