Ischemic Heart Disease

Introduction

Ischemic heart disease includes a set of conditions caused by reduced myocardial perfusion, generally due to coronary atherosclerosis. It is one of the leading causes of morbidity and mortality in industrialized countries, significantly impacting quality of life and healthcare costs.

Ischemic heart disease can present acutely, as in acute coronary syndromes (ACS), or chronically, with recurrent episodes of myocardial ischemia leading to progressive contractile dysfunction. Early diagnosis and management are essential to reduce the risk of complications such as myocardial infarction, heart failure, and ventricular arrhythmias.

Epidemiology

According to the latest epidemiological data, ischemic heart disease accounts for over 15% of global deaths, with an increasing prevalence in developing countries due to the rise in cardiovascular risk factors. In Italy, the incidence of acute coronary syndromes is approximately 120,000 cases per year, with an in-hospital mortality rate ranging from 5% to 15% depending on the severity of the event.

Risk Factors

The main risk factors for ischemic heart disease include:

• Arterial hypertension: contributes to atherosclerosis and coronary artery stiffness.
• Diabetes mellitus: promotes endothelial damage and vascular inflammation.
• Dyslipidemia: elevated LDL cholesterol and triglyceride levels accelerate atherosclerosis progression.
• Cigarette smoking: accelerates the atherosclerotic process and increases the risk of thrombotic events.
• Obesity and metabolic syndrome: associated with insulin resistance and a pro-inflammatory state.
• Sedentary lifestyle: reduces endothelial function and promotes cardiac dysfunction.
• Family history of cardiovascular disease: risk is higher in individuals with relatives affected by early ischemic heart disease.
• Stress and psychosocial factors: chronic catecholamine release may contribute to vascular dysfunction.

Pathophysiology

Myocardial ischemia occurs when oxygen supply to the myocardium is insufficient relative to its metabolic demand. This imbalance can result from:

• Coronary atherosclerosis: the formation of atheromatous plaques narrows the arterial lumen, obstructing blood flow.
• Coronary spasm: abnormal contraction of the coronary arteries, typical of vasospastic angina.
• Endothelial dysfunction: impaired nitric oxide production and reduced vasodilatory capacity.
• Thrombotic events: rupture of an atherosclerotic plaque can activate the coagulation cascade and form an occlusive thrombus.
• Coronary embolism: rare cases of ischemia caused by emboli originating from other sites.

Classification of Ischemic Heart Disease

Ischemic heart disease can be divided into two main categories:

• Acute forms: characterized by sudden and severe myocardial ischemia, as seen in acute coronary syndromes (STEMI, NSTEMI, unstable angina).
• Chronic forms: characterized by recurrent ischemia, with episodes of stable angina or silent ischemia.

Conclusions

Ischemic heart disease remains one of the major challenges in modern cardiovascular medicine. Prevention, based on risk factor control and the promotion of a healthy lifestyle, plays a fundamental role in reducing morbidity and mortality. The following sections will delve into specific clinical manifestations, from acute coronary syndrome to chronic ischemic heart disease, analyzing diagnostic and therapeutic strategies in detail.

References
1. Fuster V, et al. Pathophysiology of coronary artery disease and its clinical implications. Circulation. 2018;138(14):1452-1462.
2. Ibanez B, et al. 2017 ESC Guidelines for the management of acute myocardial infarction in patients presenting with ST-segment elevation. Eur Heart J. 2018;39(2):119-177.
3. Collet JP, et al. 2020 ESC Guidelines for NSTEMI and Unstable Angina. Eur Heart J. 2021;42(14):1289-1367.
4. Amsterdam EA, et al. 2014 AHA/ACC Guidelines for the Management of Unstable Angina. J Am Coll Cardiol. 2014;64(24):e139-e228.
5. Chiarella F, et al. Pathophysiology of Acute Coronary Syndrome. J Am Coll Cardiol. 2015;66(5):564-578.
6. Roffi M, et al. 2015 ESC Guidelines for Non-ST Elevation Acute Coronary Syndromes. Eur Heart J. 2016;37(3):267-315.
7. Pirozzoli G, et al. Role of imaging in coronary artery disease. J Cardiovasc Med. 2020;21(8):521-527.
8. Cannata A, et al. Coronary artery disease: From epidemiology to management. Heart. 2016;102(5): 371-377.
9. Ferguson TB, et al. Management strategies for NSTEMI and their implications for long-term survival. Eur Heart J. 2016;37(19):1425-1430.
10. Fox KA, et al. Acute coronary syndrome and mortality trends. JAMA Cardiol. 2022;7(7):789-797.