Predictors of premature termination of cardiac surgery trials: insights from the Clinicaltrial.gov database.

OBJECTIVES: Clinical trials that are terminated prematurely may generate incomplete and potentially biased data and the reasons for premature trials termination are poorly understood. Our objective was to describe the incidence of premature trial termination and identify factors associated with it. METHODS: We performed a systematic search on ClinicalTrials.gov to identify all cardiac surgery trials from 1991 to 2023. Trials that were terminated prematurely were identified. Factors independently associated with premature termination were identified using multivariable logistic regression analysis. RESULTS: A total of 746 clinical trials were included; of them 577 were completed and 169 (22.6%) were terminated prematurely. Most of the trials originated from North America [294 (39.4%)], Europe [264 (35.4%)] or Asia [141 (18.9%)]. Fourteen of the trials terminated prematurely (8.3%) were phase 1, 75 (44.4%) phase 2, 49 (29.0%) phase 3 and 31 (18.3%) phase 4. Fifty (29.6%) trials were terminated because of slow recruitment, 20 (11.8%) because of sponsor decision and 12 (7.1%) because of lack of funding. Left ventricular assist device trials [odds ratio (OR) 3.65, 95% confidence interval (CI) (1.65-8.00) P = 0.001], valve surgery trials [OR 4.30, 95% CI (2.33-8.00) P < 0.001], aortic surgery trials [OR 2.86 95% CI (1.22-6.43) P = 0.012], phase 2 [OR 3.02, 95% CI (1.31-7.93) P = 0.015] and phase 4 trials [OR 3.62, 95% CI (1.43-10.23) P = 0.010] were at higher risk of premature termination while trials performed in Asia [OR 0.18, 95% CI (0.07-0.39) P ≤ 0.001] and Europe [OR 0.49, 95% CI (0.30-0.80) P = 0.004] were less likely to be terminated prematurely. CONCLUSIONS: Slow recruitment is the most common reason for premature termination of cardiac surgery trials. Trials on left ventricular assist device, valve surgery, aortic surgery, phase 2 trials and phase 4 trials are more likely to be terminated, while trials conducted in Asia and Europe are less likely to be terminated prematurely.

Coronary Artery Bypass Graft Failure in Women: Incidence and Clinical Implications.

BACKGROUND: Women have worse outcomes after coronary artery bypass surgery (CABG) than men. OBJECTIVES: This study aimed to determine the incidence of CABG graft failure in women, its association with cardiac events, and whether it contributes to sex-related differences in outcomes. METHODS: A pooled analysis of individual patient data from randomized clinical trials with systematic imaging follow-up was performed. Multivariable logistic regression models were used to assess the association of graft failure with myocardial infarction and repeat revascularization between CABG and imaging (primary outcome) and death after imaging (secondary outcome). Mediation analysis was performed to evaluate the effect of graft failure on the association between female sex and risk of death. RESULTS: Seven randomized clinical trials (N = 4,413, 777 women) were included. At a median imaging follow-up of 1.03 years, graft failure was significantly more frequent among women than men (37.3% vs 32.9% at the patient-level and 20.5% vs 15.8% at the graft level; P = 0.02 and P < 0.001, respectively). In women, graft failure was associated with an increased risk of myocardial infarction and repeat revascularization (OR: 3.94; 95% CI: 1.79-8.67) and death (OR: 3.18; 95% CI: 1.73-5.85). Female sex was independently associated with the risk of death (direct effect, HR: 1.84; 95% CI: 1.35-2.50) but the association was not mediated by graft failure (indirect effect, HR: 1.04; 95% CI: 0.86-1.26). CONCLUSIONS: Graft failure is more frequent in women and is associated with adverse cardiac events. The excess mortality risk associated with female sex among CABG patients is not mediated by graft failure.

Aortic valve degeneration after valve-sparing root replacement in patients with bicuspid aortopathy or connective tissue disorder.

OBJECTIVE: We sought to evaluate outcomes of valve-sparing root replacement (VSRR) in patients with bicuspid aortopathy (BAV) versus other connective tissue disorder (CTD). METHODS: This was a single-center cohort study of consecutive patients undergoing VSRR via reimplantation from 2000 to 2023 with BAV or CTD. Operative outcomes, Kaplan-Meier survival estimates, and cumulative risk of reoperation and recurrent aortic insufficiency (AI) with the competing risk of death were assessed. RESULTS: Of 516 patients who underwent VSRR, 109 (51.9%) had BAV and 101 (48.1%) had CTD. Patients with BAV were older (46.9 ± 10.4 vs 38.4 ± 14 years, P < .001) and more likely male (89.0% vs 56.4%, P < .001) and hypertensive (66.1% vs 28.7%, P < .001). Preoperative AI was similar (P = .57) between groups (30.3% mild, 18.3% moderate, 11.1% severe). Most patients had no/trivial immediate postoperative residual AI (96.3% vs 93.1%). Operative mortality was zero; postoperative adverse events were minimal. Mean clinical follow-up was 5.2 ± 4.4 years; 10-year survival was 95.6% versus 95.7% (P = .70). Echocardiographic follow-up was 3.9 ± 4.1 years; incidence of >2+ AI (9.7% vs 10.1%, P = 1.0) was similar between groups, whereas the incidence of moderate or greater aortic stenosis was greater with BAV (7.5% vs 0%, P = .02). Reoperation was low in both groups (3.7% vs 5.9%, P = .65). Competing risk analysis found no difference in reoperation hazard between BAV and CTD groups (hazard ratio, 0.36; 95% confidence interval, 0.07-1.81, P = .21). CONCLUSIONS: Patients with BAV and CTD have excellent operative outcomes, no mortality, and minimal residual AI after VSRR. Although the incidence of recurrent AI was similar, patients with BAV are at risk for AS.

Re-exploration for bleeding and long-term survival after adult cardiac surgery: a meta-analysis of reconstructed time-to-event data.

BACKGROUND: Postoperative bleeding requiring re-exploration is a serious complication that occurs in 2.8% to 4.6% of patients undergoing cardiac surgery. Re-exploration has previously been associated with a higher risk of short-term mortality. However, a comprehensive analysis of long-term outcomes after re-exploration for bleeding has not been published. MATERIALS AND METHODS: We performed a systematic, three databases search to identify studies reporting long-term outcomes in patients who required re-exploration for bleeding after cardiac surgery compared to patients who did not, with at least 1 year of follow-up. Long-term survival was the primary outcome. Secondary outcomes were operative mortality, myocardial infarction, stroke, renal and respiratory complications, and hospital length of stay. Random-effects models was used. Individual patient survival data was extracted from available survival curves and reconstructed using restricted mean survival time. RESULTS: Six studies totaling 135,456 patients were included. The average follow-up was 5.5 years. In the individual patient data, patients who required re-exploration had a significantly higher risk of death compared with patients who did not (hazard ratio [HR]: 1.21; 95% confidence interval [CI]: 1.14-1.27; P<0.001), which was confirmed by the study-level survival analysis (HR: 1.32; 95% CI: 1.12-1.56; P<0.01). Re-exploration was also associated with a higher risk of operative mortality (odds ratio [OR]: 5.25, 95% CI, 4.74-5.82, P<0.0001), stroke (OR: 2.05, 95% CI, 1.72-2.43, P<0.0001), renal (OR: 4.13, 95% CI, 3.43-4.39 P<0.0001) respiratory complications (OR: 3.91, 95% CI, 2.96-5.17, P<0.0001), longer hospital length of stay (mean difference [MD]: 2.69, 95% CI, 1.68 to 3.69, P<0.0001), and myocardial infarction (OR: 1.85, 95% CI, 1.30-2.65, P=0.0007). CONCLUSION: Postoperative bleeding requiring re-exploration is associated with lower long-term survival and increased risk of short-term adverse events including operative mortality, stroke, renal and respiratory complications, and longer hospital length of stay. To improve both short- and long-term outcomes, strategies to prevent the need for re-exploration are necessary.

Association between overweight and obesity with coronary artery bypass graft failure: an individual patient data analysis of clinical trials.

OBJECTIVES: The association between obesity and graft failure after coronary artery bypass grafting has not been previously investigated. METHODS: We pooled individual patient data from randomized clinical trials with systematic postoperative coronary imaging to evaluate the association between obesity and graft failure at the individual graft and patient levels. Penalized cubic regression splines and mixed-effects multivariable logistic regression models were performed. RESULTS: Six trials comprising 3928 patients and 12 048 grafts were included. The median time to imaging was 1.03 (interquartile range 1.00-1.09) years. By body mass index (BMI) category, 800 (20.4%) patients were normal weight (BMI 18.5-24.9), 1668 (42.5%) were overweight (BMI 25-29.9), 983 (25.0%) were obesity class 1 (BMI 30-34.9), 344 (8.8%) were obesity class 2 (BMI 35-39.9) and 116 (2.9%) were obesity class 3 (BMI 40+). As a continuous variable, BMI was associated with reduced graft failure [adjusted odds ratio (aOR) 0.98 (95% confidence interval (CI) 0.97-0.99)] at the individual graft level. Compared to normal weight patients, graft failure at the individual graft level was reduced in overweight [aOR 0.79 (95% CI 0.64-0.96)], obesity class 1 [aOR 0.81 (95% CI 0.64-1.01)] and obesity class 2 [aOR 0.61 (95% CI 0.45-0.83)] patients, but not different compared to obesity class 3 [aOR 0.94 (95% CI 0.62-1.42)] patients. Findings were similar, but did not reach significance, at the patient level. CONCLUSIONS: In a pooled individual patient data analysis of randomized clinical trials, BMI and obesity appear to be associated with reduced graft failure at 1 year after coronary artery bypass grafting.

Association between lipoprotein levels and outcomes after coronary artery bypass grafting surgery: a systematic review and meta-analysis.

INTRODUCTION: Lipoprotein(a) (Lp[a]) is a variant of low-density lipoprotein (LDL) and has been associated with increased risk of vascular inflammation and thrombosis. Coronary artery bypass grafting (CABG) has been associated with local inflammation of the myocardium. It is plausible, therefore, that patients with elevated baseline Lp(a) may be prone to unfavorable clinical outcomes following CABG. We evaluate differences in outcomes between CABG patients with high and low serum Lp(a) in this meta-analysis. EVIDENCE ACQUISITION: A comprehensive literature search was performed to identify studies reporting outcomes in CABG patients stratified by preoperative Lp(a) level. When possible, the outcomes were pooled in a meta-analysis. We assessed post-operative mortality, major cardiovascular events, stroke occurrence and saphenous graft occlusion. EVIDENCE SYNTHESIS: Eight studies involving 8681 patients were included. Articles used varying cut-offs for high versus low Lp(a), and outcomes varied. In the three studies evaluating mortality, two showed no statistically significant difference between groups while one reported increased mortality associated with high Lp(a) level. Both studies investigating major adverse cardiovascular events reported higher risk in patients with high Lp(a). A study-level meta-analysis of four studies reporting saphenous vein graft occlusion incidence after CABG was performed. High (≥30 mg/dL) preoperative Lp(a) was not associated with an increased risk of graft occlusion compared with low (<30 mg/dL) preoperative Lp(a) (OR=1.88, 95% CI: 0.66-5.36; P=0.15). CONCLUSIONS: Studies evaluating the impact of Lp(a) on outcomes in CABG patients are few, with heterogenous cut-offs and outcomes. In the limited published studies, Lp(a) level was not associated with graft occlusion.

Subclinical hypothyroidism and clinical outcomes after cardiac surgery: A systematic review and meta-analysis.

Background: Subclinical hypothyroidism (SCH) is associated with major adverse cardiovascular events. Despite the recognized negative impact of SCH on cardiovascular health, research on cardiac postoperative outcomes with SCH has yielded conflicting results, and patients are not currently treated for SCH before cardiac surgery procedures. Methods: We performed a study-level meta-analysis on the impact of SCH on patients undergoing nonurgent cardiac surgery, including coronary artery bypass grafting and valve and aortic surgery. The primary outcome was operative mortality. Secondary outcomes were hospital length of stay (LOS), intensive care unit (ICU) stay, postoperative atrial fibrillation (POAF), intra-aortic balloon pump (IABP) use, renal complications, and long-term all-cause mortality. Results: Seven observational studies, with a total of 3445 patients, including 851 [24.7%] diagnosed with SCH and 2594 [75.3%] euthyroid patients) were identified. Compared to euthyroid patients, the patients with SCH had higher rates of operative mortality (odds ratio [OR], 2.57; 95% confidence interval [CI], 1.09-6.04; P = .03), prolonged hospital LOS (standardized mean difference, 0.32; 95% CI, 0.02-0.62; P = .04), a higher rate of renal complications (OR, 2.53; 95% CI, 1.74-3.69; P < .0001), but no significant differences in ICU stay, POAF, or IABP use. At mean follow-up of 49.3 months, the presence of SCH was associated with a higher rate of all-cause mortality (incidence rate ratio, 1.82; 95% CI, 1.18-2.83; P = .02). Conclusions: Patients with SCH have higher operative mortality, prolonged hospital LOS, and increased renal complications after cardiac surgery. Achieving and maintaining a euthyroid state prior to and after cardiac surgery procedures might improve outcomes in these patients.

Thorax support vest to prevent sternal wound infections in cardiac surgery patients-a systematic review and meta-analysis.

OBJECTIVES: Midline sternotomy is the main surgical access for cardiac surgeries. The most prominent complication of sternotomy is sternal wound infection (SWI). The use of a thorax support vest (TSV) that limits thorax movement and ensures sternal stability has been suggested to prevent postoperative SWI. METHODS: We performed a meta-analysis to evaluate differences in clinical outcomes with and without the use of TSV after cardiac surgery in randomized trials. The primary outcome was deep SWI (DSWI). Secondary outcomes were superficial SWI, sternal wound dehiscence, and hospital length of stay (LOS). A trial sequential analysis was performed. Fixed (F) and random effects (R) models were calculated. RESULTS: A total of 4 studies (3820 patients) were included. Patients who wore the TSV had lower incidence of DSWI [odds ratio (OR) = F: 0.24, 95% confidence interval (CI), 0.13-0.43, P < 0.01; R: 0.24, 0.04-1.59, P = 0.08], sternal wound dehiscence (OR = F: 0.08, 95% CI, 0.02-0.27, P < 0.01; R: 0.10, 0.00-2.20, P = 0.08) and shorter hospital LOS (standardized mean difference = F: -0.30, -0.37 to -0.24, P < 0.01; R: -0.63, -1.29 to 0.02, P = 0.15). There was no difference regarding the incidence of superficial SWI (OR = F: 0.71, 95% CI, 0.34-1.47, P = 0.35; R: 0.64, 0.10, 4.26, P = 0.42). The trial sequential analysis, however, showed that the observed decrease in DSWI in the TSV arm cannot be considered conclusive based on the existing evidence. CONCLUSIONS: This meta-analysis suggests that the use of a TSV after cardiac surgery could potentially be associated with a reduction in sternal wound complications. However, despite the significant treatment effect in the available studies, the evidence is not solid enough to provide strong practice recommendations.

The future of coronary artery bypass grafting.

Coronary artery bypass grafting has evolved considerably since it was introduced approximately 50 years ago, with continuously improved patient outcomes as a result of this growth. The most up-to-date evidence on topics such as graft patency, grafting strategy, approaches to graft harvesting, minimally invasive coronary artery bypass grafting, and postoperative pharmacotherapy may lead to changes in current accepted practice. In addition, several unanswered questions in the field of coronary artery bypass grafting may benefit from further investigation and, if resolved, might advance the field and change practice. Current or upcoming clinical trials seek to answer these unanswered questions and may generate data that yields improved outcomes and quality of life for all patients after coronary artery bypass grafting. In addition, cutting edge clinical trials designed specifically for women and racial and ethnic minorities who have had poorer outcomes and have traditionally been underrepresented in cardiovascular surgery research, have recently been launched that may change the way that a large portion of the coronary artery bypass grafting population is treated in the future.

Patient-physician sex concordance and outcomes in cardiovascular disease: a systematic review.

The sex disparity in outcomes of patients with cardiovascular disease is well-described and has persisted across recent decades. While there have been several proposed mechanisms to explain this disparity, there are limited data on female patient-physician sex concordance and its association with outcomes. The authors review the existing literature on the relationship between patient-physician sex concordance and clinical outcomes in patients with cardiovascular disease, the evidence of a benefit in clinical outcomes with female patient-physician sex concordance, and the possible drivers of such a benefit and highlight directions for future study.

Outcomes by sex in the International Study of Comparative Health Effectiveness With Medical and Invasive Approaches (ISCHEMIA) trial.

BACKGROUND: In the International Study of Comparative Health Effectiveness With Medical and Invasive Approaches (ISCHEMIA) trial, among participants with stable coronary artery disease, the risk of cardiac events was similar between an invasive (INV) strategy of angiography and coronary revascularisation and a conservative (CON) strategy of initial medical therapy alone. Outcomes according to participant sex were not reported. AIMS: We aimed to analyse the outcomes of ISCHEMIA by participant sex. METHODS: We evaluated 1) the association between participant sex and the likelihood of undergoing revascularisation for participants randomised to the INV arm; 2) the risk of the ISCHEMIA primary composite outcome (cardiovascular death, any myocardial infarction [MI] or rehospitalisation for unstable angina, heart failure or resuscitated cardiac arrest) by participant sex; and 3) the contribution of the individual primary outcome components to the composite outcome by participant sex. RESULTS: Of 5,179 randomised participants, 1,168 (22.6%) were women. Female sex was independently associated with a lower likelihood of revascularisation when assigned to the INV arm (adjusted odds ratio 0.75, 95% confidence interval [CI]: 0.57-0.99; p=0.04). The INV versus CON effect on the primary composite outcome was similar between sexes (women: hazard ratio [HR] 0.96, 95% CI: 0.70-1.33; men: HR 0.90, 95% CI: 0.76-1.07; pinteraction=0.71). The contribution of the individual components to the composite outcome was similar between sexes except for procedural MI, which was significantly lower in women (9/151 [5.9%]) than men (67/519 [12.9%]; p=0.01). CONCLUSIONS: In ISCHEMIA, women assigned to the INV arm were less likely to undergo revascularisation than men. The effect of an INV versus CON strategy was consistent by sex, but women had a significantly lower contribution of procedural MI to the primary outcome.

Intraoperative Anemia Mediates Sex Disparity in Operative Mortality After Coronary Artery Bypass Grafting.

BACKGROUND: Women undergoing coronary artery bypass grafting (CABG) have higher operative mortality than men. OBJECTIVES: The purpose of this study was to evaluate the relationship between intraoperative anemia (nadir intraoperative hematocrit), CABG operative mortality, and sex. METHODS: This was a cohort study of 1,434,225 isolated primary CABG patients (344,357 women) from the Society of Thoracic Surgeons Adult Cardiac Surgery Database (2011-2022). The primary outcome was operative mortality. The attributable risk (AR) (the risk-adjusted strength of the association of female sex with CABG outcomes) for the primary outcome was calculated. Causal mediation analysis derived the total effect of female sex on operative mortality risk and the proportion of that effect mediated by intraoperative anemia. RESULTS: Women had lower median nadir intraoperative hematocrit (22.0% [Q1-Q3: 20.0%-25.0%] vs 27.0% [Q1-Q3: 24.0%-30.0%], standardized mean difference 97.0%) than men. Women had higher operative mortality than men (2.8% vs 1.7%; P < 0.001; adjusted OR: 1.36; 95% CI: 1.30-1.41). The AR of female sex for operative mortality was 1.21 (95% CI: 1.17-1.24). After adjusting for nadir intraoperative hematocrit, AR was reduced by 43% (1.12; 95% CI: 1.09-1.16). Intraoperative anemia mediated 38.5% of the increased mortality risk associated with female sex (95% CI: 32.3%-44.7%). Spline regression showed a stronger association between operative mortality and nadir intraoperative hematocrit at hematocrit values <22.0% (P < 0.001). CONCLUSIONS: The association of female sex with increased CABG operative mortality is mediated to a large extent by intraoperative anemia. Avoiding nadir intraoperative hematocrit values below 22.0% may reduce sex differences in CABG operative mortality.

Comparative Analysis of Coronary Artery Bypass Grafting Outcomes in Women Using Different Conduits in the National UK Data Set.

BACKGROUND: There is limited report of outcomes in women undergoing isolated coronary artery bypass grafting (CABG) with left internal thoracic artery and different second conduits (saphenous vein graft [SVG], radial artery [RA], and right internal thoracic artery [RITA]). METHODS: The National Adult Cardiac Surgery Audit database was queried for women undergoing isolated CABG with left internal thoracic artery graft in the United Kingdom from 1996 to 2019. Propensity score-based pairwise comparisons were performed between graft types. The primary outcome was in-hospital mortality. RESULTS: The study included 58,063 women (SVG, n = 48,881 [84.2%]; RA, n = 6136 [10.6%]; RITA, n = 2445 [4.2%]). SVG use was stable over the years; RA and RITA use decreased. In-hospital mortality was similar between the RA and RITA grafts (2.3% vs 2.8%; odds ratio [OR], 0.80; 95% CI, 0.53-1.22; P = .39) and between the RA and SVG (2.3% vs 2.0%; OR, 1.20; 95% CI, 0.93-1.55; P = .17) but higher in the RITA group compared with the SVG (2.7% vs 1.4%; OR, 2.04; 95% CI, 1.27-3.36; P = .004). Women receiving the RITA graft were more likely to have sternal wound infection (SWI) compared with the RA (0.6% vs 0.06%; P = .004) and the SVG (0.6% vs 0.2%; P = .032). SWI was consistently associated with higher risk of in-hospital mortality. CONCLUSIONS: Conduit selection may affect operative outcomes in women undergoing CABG. The RA shows similar mortality and risk of deep SWI as the SVG.

A systematic review and meta-analysis of internal thoracic artery harvesting techniques: Skeletonized vs pedicled.

OBJECTIVES: The aim of this meta-analysis was to compare clinical and angiographic outcomes of skeletonized versus pedicled internal thoracic artery for coronary artery bypass grafting. METHODS: A comprehensive search on Ovid MEDLINE, Ovid EMBASE and Scopus was performed from inception to December 2022. The primary outcome was follow-up mortality and graft failure. Secondary outcomes were repeat revascularization, cardiovascular death and operative mortality, myocardial infarction, stroke, and sternal wound complications (SWCs). Pooled estimate for follow-up outcomes was summarized as incidence rate ratio (IRR) and 95% confidence interval (CI) while short-term outcomes were pooled as odds ratio (OR) and 95% CI. For all outcomes, inverse variance weighting was used for pooling. RESULTS: Twenty-eight studies, including 7 randomized trials and 21 observational studies, for a total of 5664 patients in the skeletonized group and 7434 in the pedicled group, were included in the analysis. At a mean weighted follow-up of 4.8 years, there was no difference in mortality between the two groups (IRR 1.14; 95% CI 0.59-2.20). However, the skeletonized group had a higher incidence of graft failure compared to the pedicled group (IRR 1.87, 95% CI 1.33-2.63) but a lower risk of SWCs (OR 0.42; 95% CI 0.30-0.60). There was no difference in short-term outcomes. CONCLUSIONS: Compared to the pedicled harvesting technique, skeletonization of the internal thoracic artery is associated with higher rate of graft failure and lower risk of SWCs without mortality difference.

Respect Versus Resect Approaches for Mitral Valve Repair: A Meta-Analysis of Reconstructed Time-to-Event Data.

Mitral valve repair (MVr) has been associated with superior long-term survival and freedom from valve-related complications compared with mitral valve replacement for primary mitral regurgitation (MR). The 2 main approaches for MVr are chordal replacement ("respect approach") and leaflet resection ("resect approach"). We performed a systematic review and a meta-analysis using 3 search databases to compare the long-term end points between both approaches. The primary end point was long-term survival. The secondary end points were long-term MR recurrence and reoperation. After reconstruction of time-to-event data for the individual survival analysis, pooled Kaplan-Meier curves for the end points were generated. A total of 14 studies (5,565 patients) were included in the analysis. The respect approach was associated with superior survival compared with the resect approach in the overall sample (hazard ratio [HR] 0.73, 95% confidence interval [CI] 0.56 to 0.96, p = 0.024, n = 3,901 patients) but not in the risk-adjusted sample (HR 1.00, 95% CI 0.55 to 1.82, p = 0.991, n = 620 patients). There was no difference between the approaches in the rate of MR recurrence in the overall sample (HR 1.39, 95% CI 0.92 to 2.08, p = 0.116, n = 1,882 patients) or in the risk-adjusted sample (HR 1.62, 95% CI 0.76 to 3.47, p = 0.211, n = 288 patients). The data for reoperation were only available in the overall sample and did not reveal a difference (HR 0.92, 95% CI 0.62 to 1.35, p = 0.663, n = 3,505 patients). In conclusion, the current evidence suggests no difference in long-term mortality, MR recurrence, or reoperation between the resect and respect approaches for MVr after adjusting for patient risk factors. More long-term follow-up data are warranted.

External Stenting for Saphenous Vein Grafts in Coronary Surgery: A Systematic Review and Meta-Analysis.

The external stenting of saphenous vein grafts (SVGs) during coronary artery bypass grafting (CABG) has been proven to reduce intimal hyperplasia (IH) in animal models, paving the way for human randomized controlled trials (RCTs) to be conducted. Herein, we performed a study-level meta-analysis to assess the impact of the Venous External SupporT (VEST) device, an external stent, on the outcomes of SVGs. A systematic search was conducted to identify all RCTs comparing VEST-stented to non-stented SVGs in patients undergoing CABG. The primary outcome was graft occlusion. The main secondary outcomes were repeat revascularization, SVG IH area, and intimal-medial thickness. Two RCTs totaling 407 patients were included. At a mean follow-up of 1.5 years, there was no difference in graft occlusion between groups (incidence rate ratio: 1.11; 95% confidence interval (CI): 0.80-1.53). The rate of repeat revascularization was also similar (odds ratio: 0.66; 95% CI: 0.27-1.64). The IH area (standardized mean difference (SMD): -0.45; 95% CI: -0.79 to -0.10) and intimal-medial thickness (SMD: -0.50; 95% CI: -0.90 to -0.10) were significantly reduced in the VEST group. Our findings show that significant reductions in the IH area and the intimal-medial thickness in VEST-stented SVGs do not currently translate into a lesser need for repeat revascularization or less graft occlusion events compared to non-stented SVGs at 1.5 years after CABG.