Mongolian Society for Pediatric Cardiology

Anesthesia & Clinical Research

Post-vaccination CABG graft thrombosis-should the Anaesthesiologist be worried?

Abstract

Author(s): Rupinder Kaur Kaiche and Rahul Kaiche

Aim: Graft patency of venous conduit, in CABG is 40-50% at 10 years, radial artery is 88-92%. Covid vaccination caused graft thrombosis in two patients within six months of surgery. We analysed the possible cause, consequences and relevance for anaesthesiologist. Method: The surgeon, anaesthesiologist and team had standardised protocols since 15 years which were judiciously followed. Results were consistent over the years. Post vaccination, angina was observed within 48 hours. Check angiography was done in one patient while other did not consent so was managed medically. Results: Angina occurred within 24-48 hours post-vaccination. Graft angioplasty was done for radial graft thrombus, while second patient was managed medically. Discussion: WHO-approved vaccines in India are-Covid shield (AZD1222) and Covaxin (BBV152), with reports of vascular thromboembolism post vaccination with AstraZeneca vaccine [1, 2, 3]. Two studies, a German/Austrian/Canadian collaboration and a Norwegian group study published online in the New England Journal of Medicine, April 9, established a causal relationship between Astra-zenec Covid-19 vaccine and severe thrombotic complications caused by rogue antibodies directed against platelet factor 4(PF4) causing massive platelet aggregation and thrombosis with reduced platelet count elsewhere resulting in bleeding. This syndrome is named Vaccine-induced immune thrombotic thrombocytopenia. Another mechanism is Kounis Syndrome, which can complicate anaesthesia, vaccination, medical therapy and stent implantation and seems associated with coronary allograft vasculopathy and Takotsubo syndrome. Kounis syndrome’s final trigger pathway is implicated in coronary artery spasm and plaque rupture, mediated by inflammatory cells like eosinophils and/or mast cells. It also affects cerebral and mesenteric arteries [9]. There is lack of knowledge regarding interactions of immunisation, anaesthesia and surgery. Since immunemodulatory effects of anaesthesia and surgical trauma may diminish immunisation, best timing of vaccination for optimal immune response against COVID-19 needs evaluation .Also side-effects of vaccine maybe aggravated through perioperative immunomodulation and its adverse effects misinterpreted as postoperative complications. Presently, the Royal College of Surgeons of England recommends non-urgent elective surgery in adults soon after vaccination and both events shall not be separated for more than one week [11]. Keywords: CABG, Graft thrombus, Covid Vaccination