Does Previous Transradial Catheterization Preclude Use of the Radial Artery as a Conduit in Coronary Artery Bypass Surgery?

The Effect of Previous Transradial Catheterization on Radial Forearm Free Flaps

Radial forearm free flaps (RFFF) are a versatile option for the reconstruction of a wide variety of soft tissue defects and are particularly common in head and neck surgery. Benefits of RFFF include a relatively short operating time, a long pedicle, and a thinner, more pliable flap. However, in addition to its role in reconstructive surgery, the radial artery may be utilized for a number of other procedures including coronary angiography and percutaneous coronary interventions. Concern has previously been raised that prior catheterization may deleteriously affect the function of the radial artery and in the field of cardiothoracic surgery, individuals are increasingly advising against its use as a graft for coronary artery bypass graft surgery in such circumstances. Despite this, little is known about the effect on RFFF. In this review article, we concisely consider the available evidence of the effect of previous transradial catheterization on the radial artery and discuss the implications for reconstructive surgery. We then summarize the key considerations regarding their use in current practice.

Predicting severe multivessel coronary artery disease to guide access strategy in patients undergoing invasive coronary angiography

INTRODUCTION

Given radial artery conduits are increasingly utilized for coronary artery bypass grafting (CABG), avoiding transradial access (TRA) for invasive coronary angiography (ICA) may benefit patients who ultimately undergo CABG. We sought to predict the likelihood of severe multivessel disease (MVD) before ICA to guide this decision.

METHODS

This was a single-center study of 1485 patients with stable symptoms who underwent ICA. A model to predict severe MVD was developed. Relative importance analyses were performed to identify clinical characteristics most associated with the presence or absence of severe MVD.

RESULTS

When predicting severe MVD, the model had a sensitivity of 70.3% and specificity of 71.8% (area under the curve = 0.7105). With a prevalence of 12.5% in our cohort, the model had a strong negative predictive value of 94.4%. Relative importance analyses showed factors most associated with the presence of severe MVD were a history of abnormal noninvasive tests, typical chest pain, aspirin use, insulin-dependent diabetes, increasing age, and a family history of coronary artery disease. Conversely, the absence of severe MVD was most associated with female sex, undergoing ICA as workup for either noncardiac or valve surgery, lung disease, atypical chest pain, and increased BMI.

CONCLUSION

Clinical information available before ICA can risk stratify the likelihood of severe MVD and therefore aid in identifying patients that may need CABG and could stand to benefit from TRA avoidance. The potential benefits of maximizing radial artery conduit availability by avoiding TRA must be balanced against the risks of alternative access on an individual patient basis.

Ultrasound Guidance for Transradial Access in the Cardiac Catheterisation Laboratory: A Systematic Review of the Literature and Meta-Analysis

BACKGROUND

Although ultrasound (US) guidance for vascular access has been widely adopted, its use for transradial access (TRA) in the cardiac catheterisation laboratory is rare. There is a perception that US guidance does not offer a clinically relevant benefit over traditional palpation-guided TRA, amplified by inconsistent findings of individual studies.

METHOD

A systematic review of MEDLINE, EMBASE and the Cochrane Library identified studies comparing US to palpation-guided TRA for cardiac catheterisation. Studies evaluating radial artery (RA) cannulation for any other reason were excluded. Event rates and risk ratios (RRs) were pooled for meta-analysis. Access failure was the primary outcome. A random-effects model was used for analysis.

RESULTS

Of the 977 records screened, four studies with a total of 1,718 patients (861 US-guided and 864 palpation-guided procedures) were included in the meta-analysis. Most procedures were elective. The pooled analysis showed US guidance significantly lowered the risk of access failure (RR 0.45; 95% confidence interval [CI] 0.21-0.97; p=0.04). Heterogeneity was moderate (I2=51.2%; p=0.105). There was a strong trend to improved first-pass success with US (RR 1.29; 95% CI 1.00-1.66; p=0.05; I2=83.8%), although no differences were found in rates of difficult access (RR 0.29; 95% CI 0.07-1.18; p=0.09; I2=88.3%). Salvage US guidance was successful in 30/41 (73.2%) patients following failed palpation-guided TRA. No differences were found in already low complication rates including RA spasm (RR 1.18; 95% CI 0.70-1.99; p=0.53; I2=0.0%) and bleeding (RR 1.32; 95% CI 0.46-3.80; p=0.60; I2=0.0%).

CONCLUSIONS

US guidance was found to improve TRA success in the cardiac catheterisation laboratory. Further investigation is necessary to determine whether routine, selective, or salvage use of US confers the most RA protection, patient satisfaction, and overall clinical benefit. (PROSPERO registration: CRD42022332238).

Is catheterization via distal transradial access feasible in children? From vessel diameter perspective

Background

Distal radial artery (DRA) access is an infrequent alternative access for pediatric catheterization. The feasibility of using the DRA for arterial catheterization in children depends on the vessel's size.

Objectives

This study aims to provide a reference for pediatric catheterization via DRA access by evaluating the diameter of the DRA in the anatomic snuffbox (AS).

Methods

We conducted a retrospective review of clinical and vascular ultrasound data of 412 children (ages 3-12) who were scheduled for arterial blood gas analysis via the DRA due to serious respiratory diseases between June 2023 and October 2023.

Results

The corrected DRA diameter in the AS was 1.97 ± 0.37 mm overall, with no significant difference between males (1.98 ± 0.38 mm) and females (1.95 ± 0.35 mm) (p = 0.457). The anteroposterior, transverse, and corrected DRA diameters increased significantly with age (p < 0.05). The DRA diameter was significantly smaller than the proximal radial artery (PRA) diameter (1.97 ± 0.37 mm vs. 2.05 ± 0.33 mm, p < 0.001) but larger than the ulnar artery (UA) diameter (1.97 ± 0.37 mm vs. 1.88 ± 0.33 mm, p < 0.001). The proportions of patients with a DRA diameter greater than 2.0 mm and 1.5 mm were 38.83% and 86.89%, respectively. The proportions of patients with DRA diameters >2.0 mm and >1.5 mm increased significantly with age (p < 0.01). The percentages of individuals with a DRA/PRA ratio ≥1.0 were 55.10% overall, 52.12% in males, and 58.60% in females. DRA diameter showed significant correlations with age (r = 0.275, p < 0.01), height (r = 0.319, p < 0.01), weight (r = 0.319, p < 0.01), BMI (r = 0.241, p < 0.01), wrist circumference (r = 0.354, p < 0.01), PRA diameter (r = 0.521, p < 0.01), and UA diameter (r = 0.272, p < 0.01).

Conclusion

The DRA diameter in children increases with age and size, making cardiac catheterization is theoretically feasible. Preoperative evaluation of the vessel diameter and intraoperative ultrasound-guided intervention are recommended for paediatric catheterization via the DRA access.

Arterial occlusion secondary to prior cardiac catheterization in a radial forearm flap-lessons learnt from an unusual case

The radial forearm free flap (RFFF) is a workhorse flap for head and neck reconstruction. We present an unusual case of radial artery occlusion, likely from previous transradial cardiac catheterization, in a patient for whom an RFFF was raised for floor of mouth reconstruction following resection of squamous cell carcinoma. Pre-operative assessment with ultrasound Doppler and an Allen test was normal. The flap was raised uneventfully under tourniquet control. However, following flap elevation and tourniquet release, poor flap perfusion was noted, and cutback of the artery revealed a long segment of hard fibrous plaque within the lumen. Retrospective review of medical records showed a history of cardiac catheterization via the same radial artery. We discuss various measures that can prevent this occurrence, including careful pre-operative screening of previous procedures involving the radial artery, the reverse Allen test, Doppler ultrasound, and consideration of distal arterial exploration without a tourniquet.

Expert systematic review on the choice of conduits for coronary artery bypass grafting: endorsed by the European Association for Cardio-Thoracic Surgery (EACTS) and The Society of Thoracic Surgeons (STS)

PREAMBLE

The finalized document was endorsed by the EACTS Council and STS Executive Committee before being simultaneously published in the European Journal of Cardio-thoracic Surgery (EJCTS) and The Annals of Thoracic Surgery (The Annals) and the Journal of Thoracic and Cardiovascular Surgery (JTCVS).

Radial artery occlusion after transradial procedures: impact on 1-year adverse events

BACKGROUND

Radial artery occlusion after transradial procedures is a frequent iatrogenic thrombotic process. The impact on prognosis has not been investigated. This study sought to investigate whether radial artery occlusion is related to increased risk of major adverse cardiac and cerebrovascular events, defined as death, myocardial infarction, stroke and coronary revascularization.

METHODS

Eight hundred thirty-seven consecutive patients who underwent a transradial coronary procedure had patency of radial artery checked at 24 hours. Radial artery occlusion occurred in 41 over 837 patients (4.8%); 764 (91.2%) were available for planned follow-up at 1 year and were included in the analysis. Event-free survival rate between patients with and without radial artery occlusion was calculated using Kaplan-Meier estimates, and Cox proportional-hazards models were used to identify independent risk factors.

RESULTS

At a median 370-day follow-up (IQR: 366-375 days), adverse events occurred in 37 patients (4.8%), 2 in patients with radial artery occlusion and 35 in patients without. One-year survival rate was 94.9% vs. 95% (unadjusted HR=1.026, 95% CI: 0.24 to 4.6, P=0.9). After multivariable modeling, age and coronary artery disease extension was associated with increased risk of adverse events.

CONCLUSIONS

Age and coronary artery disease extension were independent predictors of adverse events at follow-up. RAO had no prognostic impact.

Is STA really a low‐flow graft? A quantitative ultrasonographic study of the flow of STA for cerebral revascularization in MMD patients

OBJECTIVE

Direct revascularization remains an important tool in the treatment of patients with Moyamoya disease (MMD). The superficial temporal artery (STA) is the most commonly used donor vessel for direct bypass, and an STA graft has traditionally been considered a low-flow graft for flow augmentation. This study aimed to quantitatively evaluate the blood flow of the STA after direct revascularization.

METHODS

All direct revascularization procedures performed between 2018 and 2021 by one experienced neurosurgeon were screened. Quantitative ultrasound was used to measure the flow data of the patient's bilateral parietal branch of the STA(STA-PB), the bilateral frontal branch of the STA(STA-FB), and the left radial artery. Data on the patients' basic information, Suzuki grade, Matsushima type, anastomosis type, and blood biochemical parameters were collected and analyzed using univariate and multivariate models. An MBC Scale scoring system was proposed to evaluate the recipient artery network of the middle cerebral artery (MCA) tree. The relationship between MBC Scale score and STA graft flow was statistically analyzed.

RESULTS

In total, 81 patients (43 males and 38 females) successfully underwent STA-MCA bypass and were included in this study. The mean flow rates in the STA-PB graft on 1 day preoperatively, 1 day postoperatively, 7 days postoperatively, and >6 months postoperatively (long-term) were 10.81, 116.74, 118.44, and 56.20 mL/min respectively. Intraoperative graft patency was confirmed in all patients. Comparing the preoperative and all postoperative time points, the STA-PB flow rates were statistically significant (p < 0.001). The MCA-C score was significantly associated with postoperative flow rate on day 1 (p = 0.007).

CONCLUSION

The STA is a useful donor artery for direct revascularization inpatients with MMD and can provide sufficient blood supply to the ischemic cerebral territory.

Late Clinical Outcomes of Total Arterial Revascularization or Multiple Arterial Grafting Compared to Conventional Single Arterial with Saphenous Vein Grafting for Coronary Surgery

Coronary surgery provides better long-term outcomes than percutaneous coronary intervention. Conventional practice is to use a single arterial conduit supplemented by saphenous vein grafts. The use of multiple arterial revascularization (MAG), or exclusive arterial revascularization (TAR), however, is reported as having improved late survival. Survival is a surrogate for graft failure that may lead to premature death, and improved survival reflects fewer graft failures in the non-conventional strategy groups. The reasons for not using MAG or TAR may be due to perceived technical difficulties, a lack of definitive large-scale randomized evidence, a lack of confidence in arterial conduits, or resources or time constraints. Most people consider radial artery (RA) grafting to be new, with use representing approximately 2-5% worldwide, despite select centers reporting routine use in most patients for decades with improved results. In conclusion, the current body of evidence supports more extensive use of total and multiple arterial revascularization procedures in the absence of contraindications.

Left main coronary disease: evolving management concepts

Remarkable advances in the management of coronary artery disease have enhanced our approach to left main coronary artery (LMCA) disease. The traditional role of coronary artery bypass graft surgery has been challenged by the less invasive percutaneous coronary interventional approach. Additionally, major strides in optimal medical therapy now provide a rich menu of treatment choices in selected circumstances. Although a LMCA stenosis >70% is an acceptable threshold for revascularization, those patients with a LMCA narrowing between 40 and 69% present a more complex scenario. This review examines the relative merits of the different treatment options, addresses key diagnostic and therapeutic unknowns, and identifies future work likely to advance progress.

Radial Artery Access for Acute Coronary Syndromes: a Review of Current Evidence

PURPOSE OF REVIEW

To review the evidence supporting the use of transradial access (TRA) for percutaneous coronary intervention (PCI) in acute coronary syndromes (ACS).

RECENT FINDINGS

There have been five major randomized controlled trials (RCTs) and two recent meta-analyses comparing outcomes of TRA and femoral access (FA) in ACS. Additional studies have explored the impact of TRA on STEMI door-to-balloon (D2B) times, TRA in high-risk ACS patients, the potential conflict between TRA and coronary artery bypass graft (CABG) surgery employing the radial artery, and distal radial artery (DRA) access. TRA is associated with a reduction in net adverse clinical events, major bleeding, acute renal injury, and access site complications compared to FA in ACS patients undergoing PCI. TRA is not associated with significant delays in STEMI D2B times that impact patient outcomes. Further studies are needed to evaluate the role of TRA in high-risk ACS patients, the interplay between TRA and radial artery CABG, and use of DRA in ACS.

Contemporary coronary artery bypass graft surgery and subsequent percutaneous revascularization

Patients who have undergone coronary artery bypass graft (CABG) surgery are susceptible to bypass graft failure and progression of native coronary artery disease. Although the saphenous vein graft (SVG) was traditionally the most-used conduit, arterial grafts (including the left and right internal thoracic arteries and the radial artery) have improved patency rates. However, the need for secondary revascularization remains common, and percutaneous coronary intervention (PCI) has become the most common modality of secondary revascularization after CABG surgery. Procedural characteristics and clinical outcomes differ considerably from those associated with PCI in patients without previous CABG surgery, owing to altered coronary anatomy and differences in conduit pathophysiology. In particular, SVG PCI carries an increased risk of complications, and operators are shifting their focus towards embolic protection strategies and complex native-vessel interventions, increasingly using SVGs as conduits to facilitate native-vessel PCI rather than pursuing SVG PCI. In this Review, we discuss the differences in conduit pathophysiology, changes in CABG surgery techniques, and the latest evidence in terms of PCI in patients with previous CABG surgery, with a particular emphasis on safety and long-term efficacy. We explore the subject of contemporary CABG surgery and subsequent percutaneous revascularization in this complex patient population.

Coronary Artery Bypass Surgery After Transradial Catheterization

The 2021 ACC/AHA/SCAI coronary artery disease revascularization guideline recommends radial artery (RA) access for coronary angiography and RA grafting over saphenous vein grafting in patients referred for coronary artery bypass grafting. We present a case of a patient who underwent coronary angiography via both RAs and therefore could not receive RA bypass grafts. (Level of Difficulty: Advanced.)

Long-term consequences of transradial catheterization on the radial artery

BACKGROUND

The radial artery (RA) is often utilized for diagnostic coronary angiography and percutaneous intervention. Recent high-level evidence supports RA use in preference to the saphenous vein as a conduit for coronary revascularization.

AIM

To demonstrate gross and histologic changes of the RA following transradial (TR) access.

METHODS

We present two patients who had open RA harvest for coronary bypass surgery after TR catheterization.

RESULTS

Examination 8 years after TR catheterization demonstrated thickened intima and dissection, and examination 12 years following TR catheterization with percutaneous coronary intervention demonstrated chronic dissection with thickened intima and near occlusion of the lumen.

CONCLUSION

TR access via the RA, even after several years, is associated with significant injury, making it unusable as a conduit for surgical coronary revascularization. A RA that has been utilized for catheterization should not be considered for coronary revascularization.

PLCL vascular external sheath carrying prednisone for improving patency rate of the vein graft

Coronary artery bypass graft surgery (CABG) is an impactful treatment for coronary heart disease. Intimal hyperplasia is the central reason for the restenosis of vein grafts after CABG. The introduction of external vascular sheaths around VGs (VGs) can effectively inhibit intimal hyperplasia and ensure the patency of VGs. In this study, the well-known biodegradable copolymer poly (ε-caprolactone-co-L, L-lactide) (PLCL) was electrospun into high porosity external sheaths. The prednisone loaded in the PLCL sheath was slowly released during the degradation process of PLCL. Under the combined effects of sheath and prednisone, intimal hyperplasia was inhibited. For the cell experiments, all sheaths show low cytotoxicity to L929 cells at different concentrations at different time intervals. The ultrasonography and histological results showed prominent dilation and intimal hyperplasia of VG without sheath after two months of surgery. But there was no dilation in PLCL and PLCL_Prednisone groups. Notably, the prednisone-loaded sheath group exhibited efficacy in inhibiting intimal hyperplasia and ensured graft patency.

Never again. Once used for cardiac catherization the radial artery cannot be used for CABG

The use of the radial artery (RA) as a conduit in coronary artery bypass grafting (CABG) has been steadily increasing since the early 1990s and based on the most recent data may well become the standard of care for patients with multivessel coronary artery disease requiring multiple arterial grafts. The transradial access (TRA) approach for cardiac catherization has also increased steadily in use by interventional cardiologists owing to its reduction in bleeding and vascular complications when compared with the femoral approach and is now considered the preferred arterial access. However, prior use of TRA for cardiac catherization is a contraindication for the use of the RA for CABG because of high rates of structural damage to the vascular wall and potential for graft failure. In this issue of the Journal of Cardiac Surgery Clarke et al. examine the RA of two patients who had TRA for coronary angiography 8 and 12 years prior and note that both patients had chronic injury with dissection and obstruction of the lumen secondary to fibrosis suggesting that TRA causes long-term and irreversible damage rendering them unsuitable as conduits for CABG.

A bibliometric analysis of global research output on network meta-analysis

BACKGROUND

Network meta-analysis (NMA) has been widely used in the field of medicine and health, but the research topics and development trends are still unclear. This study aimed to identify the cooperation of countries and institutes and explore the hot topics and future prospects in the field of NMA.

METHODS

Data of publications were downloaded from the Web of Science Core Collection. We used CiteSpace V, HistCite 2.1, and Excel 2016 to analyze literature information, including years, journals, countries, institutes, authors, keywords, and co-cited references.

RESULTS

NMA research developed gradually before 2010 and rapidly in the following years. 2846 NMA studies were published in 771 journals in six languages. The PLoS One (110, 3.9%) was the most productive journal, and N Engl J Med (5904 co-citations) was the most co-cited journal. The most productive country was the United States (889, 31%) and the most productive institute was the University of Bristol (113, 4.0%). The active collaborations were observed between developed countries and between productive institutes. Of the top 10 authors, four were from the UK, and among the top 10 co-cited authors, six were from the UK. Randomized evidence, oral anti-diabetic drugs, coronary artery bypass, certolizumab pegol, non-valvular atrial fibrillation, and second-line antihyperglycemic therapy were the hot topics in this field.

CONCLUSIONS

NMA studies have significantly increased over the past decade, especially from 2015 to 2017. Compared with developing countries, developed countries have contributed more to these publications and have closer cooperation, indicating that cooperation between developed and developing countries should be further strengthened. The treatment of diabetes, cardiovascular diseases, and immune rheumatism are the main hot topics.

Coronary Artery Bypass: Review of Surgical Techniques and Impact on Long-Term Revascularization Outcomes

Coronary revascularization for multivessel disease remains a common and costly source of hospitalizations in the United States. Surgical techniques influence outcomes for coronary bypass and also affect the need for percutaneous coronary intervention in the future. As more radial access has been used for coronary angiography, consideration for use of the radial artery as a surgical conduit remains unclear. Saphenous vein grafts are commonly used for coronary bypass, however long-term patency remains suboptimal, and is also associated with a higher risk of adverse events with percutaneous coronary intervention. Thus, understanding the interplay between coronary bypass techniques and percutaneous coronary intervention has become increasingly important.

Use of the left radial artery as vascular access for coronary angiography and as a bypass conduit: A clinical dilemma?

PURPOSE

International coronary revascularization guidelines recommend both, transradial vascular access for coronary angiography/intervention and use of the radial artery as a conduit for coronary artery bypass grafting (CABG). These recommendations may pose a clinical dilemma, as transradial access exposes these arteries to vascular trauma which makes them potentially unsuitable as future grafts. In this study, we investigated the awareness and views of cardiologists on these guideline recommendations.

METHODS

We performed semi-structured interviews with 50 cardiologists from 19 centers, who regularly perform coronary angiographies or interventions, and outlined clinical scenarios to evaluate their preference of vascular access. In addition, we assessed whether preference was related to sub-specialization.

RESULTS

The interviewed cardiologists had 16 ± 9.3 years of professional experience. There were 23 (46%) cardiologists from 7 centers without percutaneous coronary intervention facilities, and 27 (56%) cardiologists from 12 interventional centers. All 50 (100%) cardiologists indicated familiarity with the guidelines, yet 28 (56%) said not to be familiar with the aforementioned dilemma, and 9 (18%) stated there was no dilemma at all. Responses did not differ significantly between interventional (n = 28) and non-interventional (n = 22) cardiologists; however, if the right radial artery was unavailable (e.g., occluded), interventional cardiologists more often said to prefer access via the left radial artery (18/28 (64%) vs. 5/22 (23%), p = 0.001).

CONCLUSION

More than half of the interviewed cardiologists indicated that they had not realized that left transradial access preceding CABG may preclude later use of this artery as a conduit. Notably, in case of unavailability of the right radial artery, interventional cardiologists preferred left transradial access more often than non-interventional cardiologists.

A novel biodegradable external stent regulates vein graft remodeling via the Hippo-YAP and mTOR signaling pathways

Coronary artery bypass graft (CABG) has been confirmed to effectively improve the prognosis of coronary artery disease, which is a major public health concern worldwide. As the most frequently used conduits in CABG, saphenous vein grafts have the disadvantage of being susceptible to restenosis due to intimal hyperplasia. To meet the urgent clinical demand, adopting external stents (eStents) and illuminating the potential mechanisms underlying their function are important for preventing vein graft failure. Here, using 4-axis printing technology, we fabricated a novel biodegradable and flexible braided eStent, which exerts excellent inhibitory effect on intimal hyperplasia. The stented grafts downregulate Yes-associated protein (YAP), indicating that the eStent regulates vein graft remodeling via the Hippo-YAP signaling pathway. Further, as a drug-delivery vehicle, a rapamycin (RM)-coated eStent was designed to amplify the inhibitory effect of eStent on intimal hyperplasia through the synergistic effects of the Hippo and mammalian target of rapamycin (mTOR) signaling pathways. Overall, this study uncovers the underlying mechanisms of eStent function and identifies a new therapeutic target for the prevention of vein graft restenosis.

Effects of the different-sized external stents on vein graft intimal hyperplasia and inflammation

Background

The poor long-term patency ratio of vein grafts prevents patients from benefiting from coronary artery bypass graft (CABG). It is reported that external venous stents have notably improved the patency ratio of stented vein grafts in animal models. The most crucial influence on stented grafts' fate is the size of the stents. This study aims to investigate the effects on intimal hyperplasia and inflammation of vein graft by using different sizes of stents and explore the potential mechanism.

Methods

Two different sizes of external stents were fabricated through 3D printing technology. Male SD rats were divided into three groups. In the control group rat's autologous left jugular vein was grafted on the ipsilateral artery directly. In the stent groups, grafts were surrounded by two different-sized stents before anastomosing with arteries. The patency ratio and diameter of the grafts were examined by ultrasound. Masson staining was used to characterize intimal hyperplasia. The expression of inflammatory factors was detected by immunohistochemical staining. Moreover, TUNEL staining was used to label apoptotic cells.

Results

The two sizes of external stents were fabricated by 3D printing technology. In the control group, the intima area and wall thickness dramatically increased 8 weeks after implantation. While in the stent groups, these data only slightly increased, especially in the 1.5 mm-stent group. The expressions of inflammatory factors in TNF signaling were more remarkable than in the control group. On the contrary, the expressions were rarely detected in the stent groups. Similarly, the number of TUNEL positive cells dramatically decreased by using the appropriate-sized stent.

Conclusions

In this study, we concluded that the appropriate sizes of external stents could effectively inhibit vein graft neointima formation, attenuate inflammatory reaction and reduce cell apoptosis, which might improve the long-term patency ratio of vein grafts.

The radial artery in coronary surgery, 2018

It is now 25 years since the radial artery (RA) was reintroduced in coronary surgery. It has evolved into being a significant coronary artery bypass conduit and ranks third in usage after the internal thoracic artery (ITA) and saphenous vein grafts (SVG). Its advantages are that it can be readily and efficiently harvested, is of good length and appropriate size for coronary artery bypass graft (CABG) surgery, is robust and easy to handle, and remains free of atheroma, and there is minimal wound morbidity. The RA must be used judiciously with attention to spasm prophylaxis because of its muscular wall, and by avoiding competitive flow. Its patency is equivalent to the ITAs when placed to similar coronary territories and under similar conditions (stenosis, size, quality) and RA patencies are always superior to those of SVG in both observational and randomized studies-88-90% versus 50-60% at 10 years, and 80-87% versus 25-40% at 20 years. Its use and excellent patencies result in survival results equivalent to bilateral internal thoracic artery (BITA) grafting and always superior to left internal thoracic artery (LITA) +SVG. Typical radial artery multiarterial bypass grafting (RA-MABG) 10-year survivals are 80-90% versus 70-80% for LITA-SVG. In general, for every 100 patients undergoing CABG, 10 more patients will be alive at 10 years post-operatively. The RA also is important in achieving total arterial revascularization, and several reports indicate a further survival advantage for patients having three arterial grafts over two. The RAs are especially useful in diabetic, morbidly obese patients, those with conduit shortage, and leg pathology, and in coronary reoperations. Although the RA has equivalent patencies to the right internal thoracic artery (RITA), it is much more versatile. RAs that have been instrumented by angiography or percutaneous coronary intervention should be avoided. The radial artery has proved to be an excellent arterial conduit, is equivalent to but more versatile than the RITA, and is always superior to SVG. Its use should be part of every coronary surgeon's skill set.

Long term outcomes of radial artery grafting in patients undergoing coronary artery bypass surgery

Single arterial left internal thoracic artery (LITA) based coronary artery bypass surgery (LITA-SABG) has been the principal revascularization strategy for over 25 years across all patient demographics. In line with the current emphasis being placed on personalized medicine, which tailors individual, patient-specific therapy to optimize outcomes, coronary artery bypass grafting (CABG) techniques have also evolved to achieve enhanced results among specific groups of patients with coronary artery disease. Most notable has been the development of multi-arterial bypass grafting (MABG) techniques, using either the radial artery (RA) or the right internal thoracic artery (RITA) in conjunction with the LITA, as both techniques have been shown to enhance long term survival of CABG patients. This article reviews the latest data on the long-term outcomes of RA-MABG and considers its impact in various sub-cohorts of CABG that are increasingly being treated by cardiac surgeons. The primary aim of this review is to highlight the advantages of RA-MABG over LITA-SABG and thereby potentiate its adoption into clinical practice. Our secondary aim is to summarize the results of RA-MABG in specific CABG sub-cohorts, to more closely align CABG surgery with the emerging consensus that personalized medicine enhances healthcare value.

Altered Hand Temperatures Following Transradial Cardiac Catheterization: A Thermography Study

BACKGROUND

There is concern about potential detrimental effects of transradial access (TRA) on radial artery structure, endothelial and hand function. This thermography study evaluated TRA impact on hand microvascular perfusion.

METHODS AND RESULTS

We prospectively measured hand thermography, radial and ulnar artery size and blood flow velocities in both catheterization and non-catheterization hands at baseline and 30-days after TRA in 158 patients. There were no differences in radial or ulnar arterial diameters or velocities pre- and post-TRA in catheterization and non-catheterization hands (p = NS). The absolute total hand thermography values post-TRA were increased in both catheterization and non-catheterization hand (pre-TRA 30.4 ± 2.9 vs. post-TRA 31.6 ± 2.6 p < 0.01; pre-TRA 30.2 ± 2.9, post-TRA 31.6 ± 2.6 p < 0.01, respectively). After ulnar artery occlusion, hand temperatures decreased in both catheterization and non-catheterization hands, both pre- and post-TRA and were similar in the catheterization and non-catheterization hands (p = NS). Total hand temperature decreased with ulnar artery occlusion and was significantly attenuated post-TRA (p < 0.001 both catheterization and non-catheterization hands).

CONCLUSIONS

TRA is associated with temperature changes in both catheterization and non-catheterization hands at one month after the index procedure. These changes likely represent a systemic response to local TRA stimulus.

Mechanisms, Consequences, and Prevention of Coronary Graft Failure

Graft failure occurs in a sizeable proportion of coronary artery bypass conduits. We herein review relevant current evidence to give an overview of the incidence, pathophysiology, and clinical consequences of this multifactorial phenomenon. Thrombosis, endothelial dysfunction, vasospasm, and oxidative stress are different mechanisms associated with graft failure. Intrinsic morphological and functional features of the bypass conduits play a role in determining failure. Similarly, characteristics of the target coronary vessel, such as the severity of stenosis, the diameter, the extent of atherosclerotic burden, and previous endovascular interventions, are important determinants of graft outcome and must be taken into consideration at the time of surgery. Technical factors, such as the method used to harvest the conduits, the vasodilatory protocol, the storage solution, and the anastomotic technique, also play a major role in determining graft success. Furthermore, systemic atherosclerotic risk factors, such as age, sex, diabetes mellitus, hypertension, and dyslipidemia, have been variably associated with graft failure. The failure of a coronary graft is not always correlated with adverse clinical events, which vary according to the type, location, and reason for failed graft. Intraoperative flow verification and secondary prevention using antiplatelet and lipid-lowering agents can help reducing the incidence of graft failure.

Long-term endothelial dysfunction after trans-radial catheterization: A meta-analytic approach

BACKGROUND

Following cardiac catheterization using radial artery (RA) access, persistent endothelial dysfunction may limit the use of RA as a conduit during coronary artery bypass graft (CABG) surgery. We reviewed published literature to investigate the effects of transradial coronary catheterization on RA endothelial function.

METHODS

We searched PubMed from inception to April 2017 for published studies assessing RA endothelial function late (≥1 month) after coronary catheterization. A total of 12 eligible published studies (n = 490 patients) were included in the final quantitative synthesis. Statistical heterogeneity among studies was assessed by the I2 . A random effects model was used to calculate the pooled estimate for standardized mean difference (SMD). Meta-regression analysis was used to explore predictors of change in RA endothelial function following catheterization.

RESULTS

In all studies, a significant reduction in endothelium dependent response was observed post-catheterization (SMD = -0.53, 95% confidence interval [CI]: -0.93 to -0.13, P = 0.01) and a marginal, non-significant, reduction in endothelium independent response (SMD = -0.38, 95%CI: -0.77, 0.01, P < 0.059). In controlled studies, using the contralateral RA as a control, a significant impairment in endothelial function was confirmed (SMD = -6.26, 95%CI: -9.71 to -2.81, P < 0.0001), while the change in endothelium-independent response was not significant (SMD = -4.46, 95%CI: -13.3 to 4.37, P = 0.32). In meta-regression analysis male gender (z = 2.36, P = 0.018) and increasing time following catheterization (z = 2.62, P = 0.009) were associated with less RA endothelial dysfunction.

CONCLUSIONS

Transradial catheterization impairs endothelium dependent vasodilatory properties of the cannulated RA, which do not recover even several months post-catheterization. Non-recovery of vasomotor function of cannulated RAs may limit their use as arterial grafts during CABG surgery.

Cardiac surgery 2016 reviewed

For the year 2016, more than 20,000 published references can be found in Pubmed when entering the search term "cardiac surgery". Publications last year have helped to more clearly delineate the fields where classic surgery and modern interventional techniques overlap. The field of coronary bypass surgery (partially compared to percutaneous coronary intervention) was enriched by five large prospective randomized trials. The value of CABG for complex coronary disease was reconfirmed and for less complex main stem lesions, PCI was found potentially equal. For aortic valve treatment, more evidence was presented for the superiority of transcatheter aortic valve implantation for patients with intermediate risk. However, the 2016 evidence argued against the liberal expansion to the low-risk field, where conventional aortic valve replacement still appears superior. For the mitral valve, many publications emphasized the significant impact of mitral valve reconstruction on survival in structural mitral regurgitation. In addition, there were many relevant and other interesting contributions from the purely operative arena in the fields of coronary revascularization, surgical treatment of valve disease, terminal heart failure (i.e., transplantation and ventricular assist devices), and aortic surgery. While this article attempts to summarize the most pertinent publications it does not have the expectation of being complete and cannot be free of individual interpretation. As in recent years, it provides a condensed summary that is intended to give the reader "solid ground" for up-to-date decision-making in cardiac surgery.

Preoperative Insight Into the Quality of Radial Artery Grafts

We investigated the impact of preoperative ultrasonography of the forearm circulation on radial artery conduit selection. Preoperative ultrasound of the forearm circulation was performed routinely in 536 patients planned for radial artery harvesting. The safety assessment of the harvest included the following algorithm of tests: the ultrasound, the Allen test, and pulse oximetry. The quality criteria that were used to exclude a radial artery from harvesting were small size of the artery, diffuse atherosclerosis, calcifications, and severe neointimal hyperplasia. The overall rejection rate due to safety reasons was 16.4%. Seventy-one (13.2%) radial arteries did not fulfill the conduit quality criteria and consequently these arteries were not harvested. In 13.4% of radial arteries, localized arterial wall disease was found in the distal third of the artery. The distal part of the artery was discarded and the rest was used as a conduit. Our results indicate that the ultrasound provides an accurate preoperative insight into the radial artery morphology, enabling selection of the arteries with favorable morphological features.