To Örebro University

INTRODUCTION: Conventional vein grafts have a high risk of thrombosis and early atherosclerosis. Percutaneous coronary intervention (PCI) in conventional vein grafts is associated with a higher incidence of late adverse cardiac events. The aim of this study was to evaluate the long-term results after PCI in saphenous vein grafts (SVG) harvested with the no-touch technique compared to the conventional technique.

METHODS: This was a single-center, retrospective, cohort study, based on data from the Swedeheart register. The inclusion criterion was individuals who underwent CABG using different vein graft techniques between January 1992 and July 2020, and who required a PCI in SVGs between January 2006 and July 2020. The primary end point was long-term in-stent restenosis. The secondary endpoints were long-term major adverse cardiac events (MACE) and 1-year re-hospitalization rates. The associations between the graft types and the endpoints were evaluated using the Fine and Gray competing-risk regression analysis.

RESULTS: The study included 346 individuals (67 no-touch, 279 conventional). The mean clinical follow-up time was 6.4 years with a standard deviation of 3.7 years. The long-term in-stent restenosis rate for the no-touch grafts was 3.2% compared to 18.7% for the conventional grafts (p < .01), with a subdistribution hazard ratio (SHR) of 0.16 (p = .010). The long-term MACE rate was 27.0% in the no-touch group and 48.3% in the conventional group (p < .01) with a SHR of 0.53 (p = .017). The short-term results were similar in both groups.

CONCLUSIONS: Percutaneous coronary intervention in a no-touch vein graft was associated with statistically significantly fewer in-stent restenoses and MACE at long-term follow-up compared to a conventional SVG.

OBJECTIVES: To evaluate the long-term angiographic patency of saphenous vein grafts (SVG) harvested using the no-touch technique compared to the conventional technique.

METHODS: This was a single-center, retrospective, cohort study. The inclusion criteria were individuals who underwent a CABG (coronary artery bypass grafting) between January 1995 and July 2020, and who successively needed a clinically-driven angiography. The primary endpoint was long-term patency. The secondary endpoints were differences in patency based on sub-group analysis (single vs. sequential graft, divided by target vessel).

RESULTS: The study included 1520 individuals (618 no-touch, 825 conventional and 77 arterial grafts). The mean clinical follow-up time was 8.4 years ± 5.5 years. The patency per patient was 70.7% in the no-touch grafts vs. 46.7% in the conventional grafts (p < 0.001, OR = 2.8). The graft patency was 75.9% in the no-touch grafts vs. 62.8% in the conventional grafts (p < 0.001, OR = 1.8). CONCLUSIONS: The no-touch vein grafts were associated with statistically significantly higher patency at long-term compared to the conventional grafts.

CLINICAL TRIAL REGISTRATION: NCT04656366, 7 December 2020.

INTRODUCTION: There is no consensus on the impact of coronary artery disease in patients undergoing transcatheter aortic valve implantation. Therefore, the objective of this study was, in a single-center setting, to evaluate the five-year outcome of transcatheter aortic valve implantation patients with or without coronary artery disease.

METHODS: All transcatheter aortic valve implantation patients between 2009 and 2019 were included and grouped according to the presence or absence of coronary artery disease. The primary endpoint, five-year all-cause mortality, was evaluated using Cox regression adjusted for age, sex, procedure years, and comorbidities. Comorbidities interacting with coronary artery disease were evaluated with interaction tests. In-hospital complications was the secondary endpoint.

RESULTS: In total, 176 patients had aortic stenosis and concomitant coronary artery disease, while 170 patients had aortic stenosis only. Mean follow-up was 2.2±1.6 years. There was no difference in the adjusted five-year all-cause mortality between transcatheter aortic valve implantation patients with and without coronary artery disease (hazard ratio 1.00, 95% confidence interval 0.59-1.70, P=0.99). In coronary artery disease patients, impaired renal function, peripheral arterial disease, or ejection fraction < 50% showed a significant interaction effect with higher five-year all-cause mortality. No significant differences in complications between the groups were found.

CONCLUSION: Five-year mortality did not differ between transcatheter aortic valve implantation patients with or without coronary artery disease. However, in patients with coronary artery disease and impaired renal function, peripheral arterial disease, or ejection fraction < 50%, we found significantly higher five-year all-cause mortality.

Background: Periprocedural stroke during transcatheter aortic valve implantation is a rare but devastating complication. The calcified aortic valve is the most likely source of the emboli in a periprocedural stroke. The total load and distribution of calcium in the leaflets, aortic root, and left ventricular outflow tract varies from patient to patient. Consequently, there could be patterns of calcification that are associated with a higher risk of stroke. This study aimed to explore whether the pattern of calcification in the left ventricular outflow tract, annulus, aortic valve, and ascending aorta can be used to predict a periprocedural stroke.

Methods: Among the 3282 consecutive patients who received a transcatheter aortic valve implantation in the native valve in Sweden from 2014 to 2018, we identified 52 who had a periprocedural stroke. From the same cohort, a control group of 52 patients was constructed by propensity score matching. Both groups had one missing cardiac computed tomography, and 51 stroke and 51 control patients were blindly reviewed by an experienced radiologist.

Results: The groups were well balanced in terms of demographics and procedural data. Of the 39 metrics created to describe calcium pattern, only one differed between the groups. The length of calcium protruding above the annulus was 10.6 mm (interquartile range 7-13.6) for patients without stroke and 8 mm (interquartile range 3-10) for stroke patients.

Conclusions: This study could not find any pattern of calcification that predisposes for a periprocedural stroke.

OBJECTIVE: To compare health-related quality of life (HRQoL) of patients primarily treated with a no-touch saphenous vein graft with that of patients who received a conventional graft.

METHODS: The study included all individuals treated with a percutaneous coronary intervention (PCI) on a saphenous vein graft (SVG) between January 2006 and June 2020. The RAND-36 health survey was used to assess HRQoL. The Mann-Whitney U test was used to test differences in HRQoL between the two groups. Effect size was estimated via Cohen's d. The average treatment effect between the groups was tested by propensity score matching (PSM).

RESULTS: Of the 346 patients treated with a PCI in a stenosed or occluded SVG, 165 responded to RAND-36 (no-touch: n=48; conventional: n=117). Patients with a no-touch graft reported better mean values on seven of the eight health survey domains. Statistically significant differences were observed for four of the domains, all in favour of the no-touch group. The effect size estimates indicated a small difference for five domains, with the highest values (>0.40) seen for the general health and energy/fatigue domains. PSM confirmed a statistically significant difference for the physical functioning and general health domains.

CONCLUSION: At a mean follow-up of 5.4 years, patients who received a PCI in no-touch vein grafts showed significantly better HRQoL than those who received a PCI in conventional vein grafts.

Adipose-derived mesenchymal stem cells (ADSCs) are promising candidates for novel cell therapeutic applications. Hibernating brown bears sustain tissue integrity and function via unknown mechanisms, which might be plasma borne. We hypothesized that plasma from hibernating bears may increase the expression of favorable factors from human ADSCs. In an experimental study, ADSCs from patients with ischemic heart disease were treated with interventional media containing plasma from hibernating and active bears, respectively, and with control medium. Extracted RNA from the ADSCs was sequenced using next generation sequencing. Statistical analyses of differentially expressed genes were performed using fold change analysis, pathway analysis, and gene ontology. As a result, we found that genes associated with inflammation, such as IGF1, PGF, IL11, and TGFA, were downregulated by > 10-fold in ADSCs treated with winter plasma compared with control. Genes important for cardiovascular development, ADM, ANGPTL4, and APOL3, were upregulated in ADSCs when treated with winter plasma compared with summer plasma. ADSCs treated with bear plasma, regardless if it was from hibernating or active bears, showed downregulation of IGF1, PGF, IL11, INHBA, IER3, and HMOX1 compared with control, suggesting reduced cell growth and differentiation. This can be summarized in the conclusion that plasma from hibernating bears suppresses inflammatory genes and activates genes associated with cardiovascular development in human ADSCs. Identifying the involved regulator(s) holds therapeutic potential.

OBJECTIVE: Concerns have been raised regarding whether skeletonization of the internal thoracic artery could damage the graft and thereby reduces its patency. The objective of this study was to compare patency rates at mid- and long-term follow-up between pedicled and skeletonized left internal thoracic artery grafts.

METHODS: This randomized controlled trial included 109 patients undergoing coronary artery bypass surgery. The patients were assigned to receive either one pedicled or one skeletonized left internal thoracic artery graft to the left anterior descending artery. Follow-up was performed at 3 years with conventional angiography, and at 8 years with computed tomography angiography. Differences between patency rates were analyzed with Fisher's exact test and a generalized linear model.

RESULTS: The patency rates for pedicled and skeletonized left internal thoracic artery grafts were 46/48 (95.8%) versus 47/52 (90.4%), p = 0.44 at 3 years, and 40/43 (93.0%) versus 37/41 (90.2%), p = 0.71 at 8 years, respectively. The difference in patency rates for pedicled and skeletonized grafts was 5.4% (95% confidence interval: -4.2-14.5) at 3 years and 2.8% (95% confidence interval: -9.9-14.1) at 8 years. All failed grafts, except for one with a localized stenosis, were anastomosed to native coronary arteries with a stenosis less than 70%. Three patients suffered sternal wound infections (two in the pedicled group, one in the skeletonized group).

CONCLUSIONS: The skeletonization technique can be used without jeopardizing the patency of the left internal thoracic artery. The most important factor in graft failure was target artery stenosis below 70%.

To investigate the results of percutaneous coronary intervention (PCI) in saphenous vein grafts after coronary artery bypass grafting (CABG). Design. MEDLINE, Embase, and the Cochrane library were searched for relevant articles published between 1 January 2000 and 29 February 2020. The PICO (population, intervention, comparison, outcome) model was applied in constructing the clinical question. Two independent researchers performed the literature search. Thirty-six articles were identified and subjected to a quality assessment. The primary outcomes of the meta-analysis were long-term in-stent restenosis and long-term major adverse cardiac events (MACE). Results. In-stent restenosis was 9.4% (95% CI: 4.2-14.7%) and MACE was 35.3% (95% CI: 27-43.7%) at mean time 2.7 ± 1.0 years. The secondary outcomes were the unsuccessful PCI rate (7.7%; 95% CI: 2.9-12.5%), 30-day MACE (4.3%; 95% CI: 2.5-6.1%), and 1-year MACE (15.5%; 95% CI: 11.7-19.3%). The use of drug-eluting stents resulted in better outcomes at least in term of in-stent restenosis, while the benefit of using embolic protection devices was questionable. Conclusions. PCI of a stenosed or occluded saphenous vein graft is a challenge for interventional cardiologists, and is still associated with relatively high rates of restenosis, MACE, and procedural failure. All efforts to enhance the results are warranted, including improved quality of the venous grafts used during CABG. 

The saphenous vein is the most commonly used conduit for coronary artery bypass grafting. Arterial grafts are harvested with the outer pedicle intact whereas saphenous veins are harvested with the pedicle removed in the conventional graft harvesting technique. This conventional procedure causes considerable vascular damage. One strategy to improve vein graft patency has been to provide external support. Ongoing studies show that fitting a metal external support improves conventionally harvested saphenous vein graft patency. On the other hand, the no-touch technique of harvesting the saphenous vein provides an improved graft with long-term patency comparable to that of the internal mammary artery. This improvement is suggested to be due to preservation of vessel structures. Interestingly, many of the mechanisms proposed to be associated with the beneficial actions of an artificial external support on saphenous vein graft patency are similar to those underlying the beneficial effect of no-touch saphenous vein grafts where the intact outer layer acts as a natural support. Additional actions of external supports have been advocated, including promotion of angiogenesis, increased production of vascular-protective factors, and protection of endothelial cells. Using no-touch harvesting, normal vascular architecture is maintained, tissue and cell damage is minimized, and factors beneficial for graft patency are preserved. In this review, the significance of external support of saphenous vein grafts in coronary artery bypass grafting is discussed.