Abstract

Ischemic heart disease (IHD) remains the most common cardiovascular disorder and the leading cause of mortality. Systemic atherosclerosis results from various risk factors, such as genetic predisposition, smoking, and diabetes. Cardio- renal-metabolic (CRM) conditions combines heart failure, dysglycemia and chronic kidney disease, increasing the risk of INOCA.

The aim of study was to examine the prevalence and optimize the treatment of microvascular angina in patients with IHD, non-stenosing coronary atherosclerosis and CRM condition.
Materials and Methods: A total of 96 patients with CRM conditions were examined, including 61 males (63,5 %) and 35 females (36,5 %) with an average age of 57,2±4,1 years. Patients underwent an exercise stress test or stress echocardiography for myocardial ischemia assessment. Following IHD confirmation, invasive coronary angiography revealed non-stenosing coronary atherosclerosis or intact coronary arteries. Coronary microvascular dysfunction was diagnosed via echocardiography with intravenous dipyridamole administration, followed by coronary flow reserve (CFR) index assessment. Microvascular dysfunction was diagnosed with CFR <2. Patients with confirmed myocardial ischemia and no significant coronary artery lesions were diagnosed with microvascular angina (INOCA).

Results: In 88 (91,7 %) patients with CRM conditions and IHD without significant coronary artery lesions the cause of ischemia was microvascular angina. The remaining 8,3 % had myocardial demand-supply mismatch due to cardiac muscle hypertrophy. Research continued with 88 patients with microvascular angina. All patients received aspirin, statins, beta-blockers, calcium channel blockers, ACE inhibitors/sartans, indapamide, SGLT2 inhibitors, and metformin. Doses of metformin were adjusted for 49 patients, and liraglutide was added for 11. For all patients we added nicorandil. After 28 days of nicorandil therapy, 96,6 % of patients were free of angina symptoms. Nicorandil normalized coronary microvascular function in 89,8 % and clinically relieved symptoms in 96,6 %.

Conclusion: In 91,7 % patients with CRM conditions and IHD without significant coronary artery lesions, ischemic complaints are due to microvascular angina. Nicorandil in combination therapy achieves a clinical effect in 96,6 % of cases and normalizes coronary flow reserve in 89,8 % of patients.

Key words: myocardial ischemia, coronary microvascular dysfunction, microvascular angina, stress-echocardiography, nicorandil

1. Jespersen L., Hvelplund A., Abildstrøm S.Z., Pedersen F., et al. Stable angina pectoris with no obstructive coronary artery disease is associated with increased risks of major adverse cardiovascular events. Eur Heart J. 2012;33(6):734-744. https://doi.org/10.1093/eurheartj/ehr331
2. Jia Q, Shi S, Yuan G, Shi J, Shi S, et al. The effect of nicorandil in patients with cardiac syndrome X: a meta-analysis of randomized controlled trials. Medicine (Baltimore). 2020, 99:e22167. 10.1097/MD.0000000000022167
3. Jiang X, Wu D, Jiang Z, Ling W, Qian G: Protective effect of nicorandil on cardiac microvascular injury: role of mitochondrial integrity. Oxid Med Cell Longev. 2021:4665632. 10.1155/2021/4665632
4. Kang S. The diagnostic performance of adenosine-stress myocardial perfusion imaging versus dipyridamole-stress myocardial perfusion imaging for detecting coronary artery disease: a systematic review and meta-analysis. Journal of Nuclear Cardiology 28.6 (2021): 2247-2262.
5. Kunadian V., Chieffo A., Camici P.G., Berry C., Escaned J., et al. An EAPCI Expert Consensus Document on Ischaemia with Non-Obstructive Coronary Arteries in Collaboration with European Society of Cardiology Working Group on Coronary Pathophysiology & Microcirculation Endorsed by Coronary Vasomotor Disorders International Study Group. Eur Heart J. 2020;41(37):3504-3520. https: //doi.org / 10.1093 / eurheartj/ehaa503