Radial artery versus saphenous vein versus right internal thoracic artery for coronary artery bypass grafting

Confounding adjustment in observational studies on cardiothoracic interventions: a systematic review of methodological practice

OBJECTIVES

It is unknown which confounding adjustment methods are currently used in the field of cardiothoracic surgery and whether these are appropriately applied. The aim of this study was to systematically evaluate the quality of conduct and reporting of confounding adjustment methods in observational studies on cardiothoracic interventions.

METHODS

A systematic review was performed, which included all observational studies that compared different interventions and were published between 1 January and 1 July 2022, in 3 European and American cardiothoracic surgery journals. Detailed information on confounding adjustment methods was extracted and subsequently described.

RESULTS

Ninety-two articles were included in the analysis. Outcome regression (n = 49, 53%) and propensity score (PS) matching (n = 44, 48%) were most popular (sometimes used in combination), whereas 11 (12%) studies applied no method at all. The way of selecting confounders was not reported in 42 (46%) of the studies, solely based on previous literature or clinical knowledge in 14 (16%), and (partly) data-driven in 25 (27%). For the studies that applied PS matching, the matched cohorts comprised on average 46% of the entire study population (range 9-82%).

CONCLUSIONS

Current reporting of confounding adjustment methods is insufficient in a large part of observational studies on cardiothoracic interventions, which makes quality judgement difficult. Appropriate application of confounding adjustment methods is crucial for causal inference on optimal treatment strategies for clinical practice. Reporting on these methods is an important aspect of this, which can be improved.

Twenty-year outcomes of free and I-composite radial artery grafts for coronary artery revascularization

PURPOSE

To compare the 20-year outcomes of coronary artery grafting (CABG) using radial artery (RA) grafts (free and I-composite) and internal thoracic artery (ITA) grafts.

METHODS

Long-term graft patency was evaluated in patients who underwent isolated CABG between August, 1996 and January, 2022. The long-term graft patency of free RA grafts, I-composite ITA-RA grafts, and saphenous vein (SV) grafts were compared.

RESULTS

The RA was used as a coronary bypass conduit in 111 of the 246 patients enrolled in this study. The RA patency after 10 and 20 years was 94.2% and 76.6%, respectively. Landmark analysis showed that although graft patency for up to 10 years did not differ between the RA and ITA grafts (hazard ratio = 0.87; P = 0.8), patency of the ITA grafts was better from 10 to 20 years post-surgery (hazard ratio = 0.19; P = 0.013). The 20-year graft patency of the I-composite RA grafts was better than that of the free RA grafts (80.0% vs. 72.4%; P = 0.029), but not significantly different from that of the ITA grafts (80.0% vs. 90.7%; P = 0.24).

CONCLUSIONS

The 20-year patency of the I-composite ITA-RA graft was better than that of the free RA graft; therefore, the I-composite graft may be an effective conduit for CABG.

Risk factors for major adverse cardiovascular events after coronary artery bypass grafting using radial artery grafts

Background

Coronary artery bypass grafting using radial artery grafts (RA-CABG) has improved long-term outcomes. However, major adverse cardiovascular events (MACE-4, including all-cause death, myocardial infarction, stroke, and repeat revascularization) after RA-CABG still occur and the predictors remain uncertain. This study aimed to detect independent risk factors of MACE-4 after RA-CABG.

Methods

This is a retrospective case-control study (NCT04935086) conducted among patients who underwent primary isolated RA-CABG between 2009 and 2019 in our center. Baseline characteristics, procedure characteristics, and medication use were compared to identify the independent predictors of MACE-4, all-cause death, and myocardial infarction (MI) with univariate and then multivariate logistic regression.

Results

A total of 370 patients were analyzed using a mean follow-up duration of 48.8 ± 41.0 months. MACE-4, all-cause death, and MI occurred in 102 (27.6%), 27 (7.3%), and 66 patients (17.8%), respectively. Multivariate analysis revealed prior MI (OR = 2.12, 95%CI 1.05-4.25, P = 0.04) and RA to the left anterior descending artery (LAD) (non-left internal mammary artery to LAD) (OR = 4.87, 95%CI 1.41-16.82, P = 0.01) as independent predictors of MACE-4 after surgery. Female (OR = 4.53, 95%CI 1.06-19.41, P = 0.04), left ventricular ejection fraction (LVEF) <40% (OR = 21.00, 95%CI 1.20-368.35, P = 0.04), and RA to LAD (OR = 8.55, 95%CI 1.35-54.10, P = 0.02) were independent predictors of all-cause death. Prior MI (OR = 3.11, 95%CI 1.40-6.94, P = 0.006) emerged as an independent predictor of MI.

Conclusion

Our data suggested that prior MI and RA to LAD were independent predictors of MACE-4 after RA-CABG. Being female, having an LVEF < 40% and RA to LAD indicated death. Prior MI indicated new MI.

Graft Patency of No-Touch Saphenous Veins Used as Aortocoronary Bypass Grafts

Background

This study evaluated the early, 1-year, and 3-year graft patency rates and mid-term clinical outcomes after no-touch saphenous veins (NT-SVs) were used as aortocoronary grafts in coronary artery bypass grafting (CABG).

Methods

In total, 101 patients who underwent CABG using NT-SVs as aortocoronary grafts were included. The 2 most common indications for performing aortocoronary grafting with NT-SVs were unavailability of the left internal thoracic artery (n=36) and moderate lesions where flow competition was expected (n=27). Early (median, 1 day; interquartile range [IQR], 1-2 days), 1-year (median, 13 months; IQR, 11-16 months), and 3-year (median, 34 months; IQR, 27-41 months) graft angiography was performed in 98 (97.0%), 84 (83.2%), and 40 patients (39.6%), respectively. The median follow-up duration was 43 months (IQR, 13-76 months). Overall survival rates and the cumulative incidence of major adverse cardiac events were evaluated.

Results

The operative mortality rate was 2% (2 of 101 patients). Early postoperative patency rates for overall and aortocoronary NT-SV grafts were 98.2% (223 of 227 distal anastomoses) and 98.2% (164 of 167), respectively. The 1- and 3-year patency rates for aortocoronary SV grafts were 94.9% (131 of 138) and 90.6% (58 of 64), respectively. The overall survival rates at 5 and 10 years were 81.7% and 59%, respectively. The cumulative incidence of major adverse cardiac events at 5 and 10 postoperative years was 20.7% and 39%, respectively.

Conclusion

The feasibility of using NT-SVs as aortocoronary grafts in CABG was shown in this study, based on the graft patency rates up to 3 years and the mid-term clinical outcomes.

The Feasibility and Early Results of Multivessel Minimally Invasive Coronary Artery Bypass Grafting for All Comers

OBJECTIVES

Cardiovascular surgery advancements have emerged with various minimally invasive approaches for treating multivessel coronary disease to improve outcomes and minimize the burden associated with conventional cardiac surgery. We present our clinical experience and minimally invasive coronary bypass techniques through minithoracotomy, which we apply without selection to patients who have decided to have elective surgery for multivessel isolated coronary artery disease.

METHODS

It consists of 230 consecutive patients operated by the same team with this method between July 2020 and September 2022. The patients were assigned to one of the two methods preoperatively to their accompanying comorbidities and operated on either with blood cardioplegia via 5 to 7 cm left anterior minithoracotomy, with on-pump clamped technique or without pump via left anterolateral minithoracotomy.

RESULTS

Mortality was observed in two of our patients (0.9%), but myocardial infarction was not observed in our patients in the early postoperative period. None of our patients required conversion to sternotomy (0%). Five patients' needed reoperation from the same incision due to postoperative bleeding (2.2%), and atrial fibrillation developed in 17 patients in the postoperative period (7.4%). The mean number of bypasses was found to be 3.0 ± 0.9.

CONCLUSIONS

Minimally invasive coronary artery bypass surgery via minithoracotomy can be routinely reproduced safely. More long-term results and more multicenter studies are needed for more widespread acceptance of the technique.

Cardiac Surgery 2022 Reviewed

PubMed displayed almost 37,000 hits for the search term "cardiac surgery AND 2022." As before, we used the PRISMA approach and selected relevant publications for a results-oriented summary. We focused on coronary and conventional valve surgery, their overlap with interventional alternatives, and briefly assessed surgery for aorta or terminal heart failure. In the field of coronary artery disease (CAD), key manuscripts addressed prognostic implications of invasive treatment options, classically compared modern interventions (percutaneous coronary intervention [PCI]) with surgery (coronary artery bypass grafting [CABG]), and addressed technical aspects of CABG. The general direction in 2022 confirms the superiority of CABG over PCI in patients with anatomically complex chronic CAD and supports an infarct-preventative effect as underlying mechanism. In addition, the relevance of proper surgical technique to achieve durable graft patency and the need for optimal medical treatment in CABG patients was impressively illustrated. In structural heart disease, the comparisons of interventional and surgical techniques have been characterized by prognostic and mechanistic investigations underscoring the need for durable treatment effects and reductions of valve-related complications. Early surgery for most valve pathologies appears to provide significant survival advantages, and two publications on the Ross operation prototypically illustrate an inverse association between long-term survival and valve-related complications. For surgical treatment of heart failure, the first xenotransplantation was certainly dominant, and in the aortic surgery field, innovations in arch surgery prevailed. This article summarizes publications perceived as important by us. It cannot be complete nor free of individual interpretation, but provides up-to-date information for decision-making and patient information.

Long-term outcomes of patients receiving right internal thoracic artery or radial artery as a second arterial conduit. A propensity score matching study

OBJECTIVE

This study aimed to compare the long-term outcomes in propensity matched patients receiving right internal thoracic artery(RITA) or radial artery(RA) as second arterial conduit during coronary artery bypass grafting(CABG) with internal thoracic artery to the left anterior descending artery(LAD).

METHODS

In this retrospective study, propensity score matching was performed including 1198 patients from 3 centers resulting in 389-pairs who received either RITA or RA.

RESULTS

In the matched cohort, median follow-up time was 7.53 years(interquartile range, 4.35-11.81). Survival probabilities at 5, 10 and 15-years were 93.8% versus 94.5%, 81.2% versus 76.2% and 63.2% vs 62.5% in the RITA and RA groups, respectively(HR: 1.11; 95%CI;0.80-1.53; P = 0.533) Freedom from MACCE in the matched cohort at 5, 10 and 15-years were 92.0% versus 93.7%, 75.0% versus 73.8%, 72.2% and 46.9% vs 47.2% in the RITA and RA groups, respectively(HR: 0.96; 95%CI;0.74-1.26; P = 0.774). Subgroup analyses of the matched cohort showed comparable long-term outcomes in terms of MACCE at follow-up in patients with age older than 65-years, obese patients, diabetics, female patients and with impaired EF. As for target vessel revascularization, RITA and RA had comparable outcomes in terms of MACCE when the conduit was used to graft either the left coronary system or the right coronary system.

CONCLUSIONS

The use of RITA or RA as second arterial conduit during CABG with internal thoracic artery to the LAD is safe and associated with comparable long-term clinical outcomes. The choice of optimal second arterial conduit should be guided mainly by patients' characteristics and surgeons' preferences.

Long-term survival in coronary artery bypass grafting surgery depending on the second conduit used

There is still debate whether radial artery (RA) conduits are better grafts then saphenous vein grafts (SVG) as a second conduit in coronary artery bypass grafting (CABG) surgery. Although it has been confirmed that RA grafts have significantly better patency over years, only some observational studies have associated RA use with reduced all-cause mortality. So far, no randomized controlled trial (CRT) has confirmed significantly better survival for RA graft recipients versus SVG recipients. Therefore, we have to wait for the results of the ongoing ROMA (CRT) study, to draw relevant conclusions about the impact of the second graft on long-term survival in patients undergoing CABG surgery.