The Barriers to Rapid Reperfusion in Acute ST-Elevation Myocardial Infarction.

INTRODUCTION: This study aimed to quantify the contribution of various obstacles to timely reperfusion therapy in acute ST-elevation myocardial infarction (STEMI) and to improve performance in a mixed remote rural/urban region. METHODS: From November 1, 2020 to April 23, 2021, patients with acute STEMI were prospectively monitored with the critical time intervals, treatment modalities, and outcomes registered. Selected clinical decision-makers in 11 hospitals were appointed as improvement agents and systematically provided with weekly updated information about absolute and relative performance. Suggestions for improvements were invited and shared. RESULTS: Only 29% of the 146 patients received reperfusion therapy within recommended time limits [prehospital thrombolysis, 2/48; in-hospital thrombolysis, 0/20; primary percutaneous coronary intervention (pPCI), 37/68, with median intervals from the first medical contact of 44, 49, and 133 min, respectively]. Efficiency varied considerably between health trusts: median time from the first medical contact to prehospital thrombolysis ranged from 29 to 54 min (hazard ratio 4.89). The predominant, remediable causes for delays were erroneous tactical choices and protracted electrocardiographic diagnostication, decision-making, and administration of fibrinolytic medication. During the trial, the time to pPCI was non-significantly reduced. CONCLUSION: We found several targets for system improvements in order to mitigate reperfusion delays along the entire chain of care, regardless of reperfusion modality chosen. More patients should receive prehospital thrombolysis. The most important measures will be training to ensure a more efficient on-site workflow, improved protocols and infrastructure facilitating the communication between first responders and in-hospital clinicians, and education emphasizing prehospital transport times. CLINICAL TRIALS IDENTIFIER: NCT04614805.

The risk factors for radial artery and saphenous vein graft occlusion are different.

Objectives. To determine risk factors for radial artery and saphenous vein graft occlusion during long-term follow-up after coronary artery bypass grafting (CABG). Methods: From a cohort of 119 patients who had received a radial artery graft, 76 - of whom 55 also had at least one saphenous vein graft - underwent a preplanned direct angiography and anthropometric, biochemical, and endothelial function assessment 7.6-12.1 (mean 8.9) years after CABG. Comorbidity, medication, and smoking habits were also recorded. The association between these parameters and conduit longevity was analyzed in univariable and multivariable logistic regression models. Results: Radial artery graft occlusions were associated with higher plasma levels of high-sensitive C-reactive protein and patency was best among patients with pharmacologically treated hypertension. The sole independent risk factor identified for saphenous vein graft occlusion was tobacco smoking 8-12 years postoperatively. Conclusion: Our data support the contention that the pathogenesis of radial artery graft failure is distinct from vein graft disease and is related to hypertension status and systemic inflammation. These risk factors are potential targets for preventive measures. Accordingly, the study supports the eventual design of personalized secondary prevention regimens.Clinical registration number: ISRCTN23118170.

Direct angiography demonstrates equal 8-12 years patency rates of radial artery and saphenous vein grafts.

Objectives: The benefits of coronary artery bypass surgery depend on lasting graft patency. To aid rational graft selection, the relative long-term merits of radial artery and saphenous vein grafts need to be determined by a gold standard method and with minimal clinically driven selection bias. Methods: The patency rates of various conduits were determined by direct angiography in 76 patients from a cohort of 119 undergoing coronary artery bypass grafting 7.6-12.1 (mean 8.9) years before. Results: 14 out of 76 radial artery and 10 out of 61 saphenous vein grafts were occluded (rates 0.18 and 0.16, respectively). Conclusion: The high long-term patency rate of saphenous vein grafts does not support a preferential use of the radial artery as a coronary artery bypass conduit. Clinical registration number: ISRCTN23118170.

Radial artery graft patency relates to gender, diabetes mellitus and angiotensin inhibition.

UNLABELLED: The radial artery is resistant to atherosclerotic degeneration and therefore appears more attractive for coronary artery bypass grafting than the saphenous vein. However, the patency of radial artery grafts varies widely among studies. Therefore, before deciding whether to adopt this as the conduit of choice second to internal mammary artery grafts, we have prospectively monitored our first cohort of patients with radial-to-coronary bypasses. DESIGN: Angiographic and clinical outcome parameters were registered for the 119 patients receiving radial artery grafts at our institution during April 4, 2001 to October 7, 2003. RESULTS: Reangiography of 102 patients (86%) showed that after two to three years, 79% of the radial artery and 87% of the saphenous vein grafts remained patent. Radial artery harvesting was well tolerated. Patency of radial artery grafts was correlated to diabetes mellitus (detrimental), gender (women had higher occlusion rates), and use of angiotensin inhibiting medication (beneficial). CONCLUSIONS: The pre-study assumption that radial artery grafts would out-perform those of saphenous vein at mid-term is not borne out. The propensity of radial artery graft failure in diabetics and the higher patency associated with angiotensin inhibition might both relate to endothelial modulation of the muscular tone of the graft.