Metformin use during the periprocedural period in diabetic individuals having invasive coronary angiography does not raise lactate levels and was not linked to any loss in renal function, says an article published in Cardiovascular Diabetology.
Due to an apparent risk of metformin-associated lactic acidosis (M-ALA), it is customary to stop taking the drug before invasive coronary angiography, despite the lack of reliable data. In order to evaluate the safety of metformin continuation in diabetic patients having coronary angiography in terms of a considerable increase in lactate levels, Mauro Chiarito and colleagues conducted this study.

All diabetic patients receiving coronary angiography at 3 European locations, with or without percutaneous coronary intervention, were screened for enrollment in an open-label, multicenter, prospective, single-arm experiment. The main outcome was the change in lactate levels from baseline 72 hours following the surgery. Secondary outcomes were death from all causes, M-ALA, and contrast associated acute kidney injury (CA-AKI).
The key findings of this study were:
1. There were 142 diabetic individuals receiving metformin treatment.
2. The interquartile range (IQR) for the median preprocedural lactate level was 1.3–2.3 and it was 1.8 mmol/l.
3. Lactate levels were 1.7 mmol/l (IQR 1.3-2.3) after 72 hours following coronary angiography, with no appreciable variations from baseline (p = 0.91; median difference = 0; IQR 0.5 to 0.4 mmol/l).
4. There were no cases of M-ALA recorded, however one patient had 72-h levels that were less than 5 mmol/l (5.3 mmol/l).
5. CA-AKI occurred in 9 patients (6.1%), and during the perioperative period, both the median serum creatinine and the estimated glomerular filtration rate remained stable.
6. No patients required hemodialysis at a median follow-up of 90 days (43–150), and 2 patients passed away from non-cardiac reasons.
One of the most frequently used medications by patients scheduled for coronary angiography is metformin, which is advised as first-line treatment for those with type 2 diabetes. The current study adds to the scant information about the safety of continued metformin use in individuals receiving coronary angiography and percutaneous coronary intervention.
Reference:
Chiarito, M., Sanz-Sanchez, J., Piccolo, R., Condello, F., Liccardo, G., Maurina, M., Avvedimento, M., Regazzoli, D., Pagnotta, P., Garcia-Garcia, H. M., Mehran, R., Ferrante, G., & Stefanini, G. (2023). Safety of metformin continuation in diabetic patients undergoing invasive coronary angiography: the NO-STOP single arm trial. In Cardiovascular Diabetology (Vol. 22, Issue 1). Springer Science and Business Media LLC. https://doi.org/10.1186/s12933-023-01744-4