What is Chronic Ischemic Heart Disease Selection of Treatment Modality (Longterm Coronary Artery Disease)?
Stable ischemic heart disease (SIHD) is often used to refer to chronic coronary artery disease (CAD). In simple words, it involves certain conditions where the heart can’t get as much oxygen as it needs, usually due to blockage in the arteries because of a condition called atherosclerosis. But it’s not just blockage; other issues like artery spasms, problems with small blood vessels, or heart defects from birth can also cause SIHD.
According to the 2012 guidelines from the American College of Cardiology (ACC) and the American Heart Association (AHA), SIHD can include adults who already have known heart disease and experience constant chest pain, or those who have new chest pain that’s low-risk. Even those who don’t have any symptoms but have been diagnosed through other methods, or those who no longer have symptoms after treatment or surgery also fall under SIHD.
It’s important to understand the difference between stable ischemic heart disease and acute coronary syndrome (ACS), which is a more serious condition where the heart is suddenly deprived of its oxygen supply. To diagnose ACS, there should be signs of damage to the heart muscle, or high-risk chest pain without heart muscle damage. However, it’s worth noting that people with SIHD can gradually worsen, with their chest pain becoming more frequent, or they may develop ACS and need immediate treatment. Therefore, it’s crucial to identify whether a person has SIHD or ACS among people suffering from blocked arteries due to atherosclerosis.
What Causes Chronic Ischemic Heart Disease Selection of Treatment Modality (Longterm Coronary Artery Disease)?
The chronic restriction of blood supply, also known as chronic ischemia, is primarily caused by obstruction in the heart’s blood vessels due to a disease called atherosclerosis. A recently identified condition common among females involves damage or dysfunction of the inner lining of the blood vessels or improper blood circulation regulation at the minute level. This condition presents similar symptoms but with no observable narrowing or blockage in angiography (a test that uses X-rays to show your blood vessels).
Less frequent causes include the sudden tightening of the heart’s blood vessels known as coronary vasospasm, which can lead to a form of chest pain called Prinzmetal angina, and rare anomalies in the heart’s blood vessels. These conditions might sometimes exhibit similar symptoms as well.
Risk Factors and Frequency for Chronic Ischemic Heart Disease Selection of Treatment Modality (Longterm Coronary Artery Disease)
Stable ischemic heart disease might be tough to measure due to the differing understandings among doctors and the variety of people it affects. This heart condition, known as CAD, is nonetheless a significant health concern. It’s estimated that 10 million adults in the United States have been diagnosed with it. Despite treatments aimed at reducing death rates, CAD alone caused nearly 380,000 deaths in the U.S in 2010, making it the leading cause of death for both men and women. The use of advanced therapies has improved survival rates, which has led to a larger elderly population with this condition. In fact, over 20% of women and 35% of men above 80 years of age suffer from coronary artery disease.
Signs and Symptoms of Chronic Ischemic Heart Disease Selection of Treatment Modality (Longterm Coronary Artery Disease)
Stable ischemic heart disease, often linked to atherosclerosis, is a medical condition associated with discomfort in the chest, particularly on the left side and beneath the breastbone. This discomfort is generally known as angina and is primarily triggered by intense physical activity or stress and can be soothed by resting or taking nitroglycerin. Patients describe their discomfort variously as a kind of heaviness, pressure, squeezing, or tightness in the chest. This discomfort can also extend to the left arm, neck, or jaw. However, if it is classified as genuine ‘pain,’ can be felt upon touching the chest, changes with breathing, or can be precisely located by the patient, the likelihood of it being ischemia (reduced blood flow) is lower.
It’s worth noting that individuals can experience “angina-equivalent” symptoms. In such instances, instead of the typical chest discomfort, they might experience shortness of breath when they exert themselves, or more unconventional symptoms may occur that limit their physical function. This is particularly common in older people, women, or those suffering from diabetes. Among these groups, silent ischemia (or heart attack without symptoms) can also occur not infrequently.
Stable angina is distinguished from its unstable counterpart by its pattern and predictability. The symptoms usually last for a few minutes (not seconds or hours) after a certain amount of exertion, then recede when the person rests. If this stable and predictable pattern of angina changes – i.e., it occurs with less exertion, lasts longer, or becomes more intense – immediate medical evaluation for unstable angina is required.
From a clinical perspective, if three criteria are met (chest discomfort beneath the breastbone, triggered by exertion or emotion, and relieved by rest or nitroglycerin), it’s considered typical angina. This implies a high probability that ischemic heart disease is causing the chest discomfort. If a patient doesn’t meet all three criteria, their condition may be classified as atypical angina or non-cardiac chest pain, depending on how many criteria they meet and how they describe their symptoms.
A crucial point to note is that stable ischemic heart disease can be entirely without symptoms. Studies show that atherosclerosis, the most common precursor to heart disease, can start as early as childhood and develop over several decades without any symptoms. Symptoms only appear when the disease has significantly progressed, and obstruction of the coronary artery reaches or exceeds 50% of the vessel. This makes proactive screening of patients at intermediate or higher risk critical to begin treatment as soon as possible.
Testing for Chronic Ischemic Heart Disease Selection of Treatment Modality (Longterm Coronary Artery Disease)
The first step to screen for stable ischemic heart disease is to identify risk factors that can lead to clogged arteries. These risk factors include growing older, being male, smoking, high blood pressure, diabetes, high cholesterol, and a family history of early onset heart disease. Being overweight, not getting enough physical exercise, stress or depression, chronic kidney disease, or having another form of heart disease can also be associated with ischemic heart disease.
In 2010, health associations ACC/AHA suggested using combined risk scores such as the Framingham Risk Score to assess everyone’s risk for heart disease. Later, in 2013, a new risk assessment tool recommended for African American or white patients aged between 40 and 79 was added to the guidelines. All these risk evaluators rely on similar risk factors previously mentioned. However, it is difficult to calculate some risk factors such as family history of heart disease and doctors should remember to take these into account when assessing each patient.
The 2013 ACC/AHA guidelines also used a new risk calculator to assess all adults over 21 years old. People with heart disease, very high cholesterol, diabetes, or a calculated risk of heart disease in the next 10 years of more than 20% are considered high risk, and high intensity medication (statins) might be needed.
Patients with medium or borderline risk (5-20%) are advised to discuss their individual risk factors before deciding to start statin therapy. Other tools like the coronary artery calcium (CAC) score can be useful for detailed risk assessments. Other factors can also increase the risk of heart disease, such as high levels of hs-CRP, a low ABI score, or high Lp(a) or apoB levels.
Modern guidelines also rely on risk calculators, but have added cholesterol targets for statin therapy and for managing lipid levels. Regardless of the guidelines used, it’s crucial to screen for those at higher risk and recommend lifestyle changes and lipid-lowering medication while patients are still without symptoms.
For patients suspected or known to have stable ischemic heart disease, initial evaluation should start with a detailed history and physical examination, along with a baseline heart recording (ECG). Patients may need to have their heart monitored or tested under stress conditions. Performing an ultrasound of the heart (echocardiogram) is critical to find ventricular dysfunction as it directly affects the treatment plan. Blood tests to assess cholesterol levels, HbA1c, and renal function are usually obtained. Troponin enzyme or brain natriuretic peptide (BNP) levels aren’t needed for the diagnosis but might be useful in specific cases.
After initial testing, the decision to proceed with invasive testing, like cardiac catheterization, can be made. It gives detailed information about the heart’s anatomy with the aim of finding atherosclerotic lesions. But this kind of testing may only be necessary if the results are expected to influence the treatment plan. A coronary angiogram may be used to diagnose ischemic heart disease in patients with atypical presentation or inconclusive test results, but it’s typically not performed for diagnostic purposes only. It provides an additional layer of risk assessment which can guide qualifying patients towards revascularization interventions like PCI procedure or bypass surgery.
The 2014 guidelines suggest performing coronary angiography in high-risk patients, whose symptoms are not relieved by medication or if the diagnostic tests are inconclusive. Coronary angiography is not recommended for asymptomatic patients, those with low risk, or if the patients aren’t potential candidates for revascularization. It exposes them to the risks of the procedure without affecting future management or improving outcomes.
Treatment Options for Chronic Ischemic Heart Disease Selection of Treatment Modality (Longterm Coronary Artery Disease)
The primary goal of treating atherosclerotic diseases is to limit progression, prevent or reduce complications, and almost entirely eliminate symptoms. This is in order to improve the patient’s quality of life and restore their normal functional capacity. There are three main ways to achieve this: modifying risk factors, directed medical therapy, and revascularization.
Modifying risk factors begins with changes to individual lifestyle habits. These include changes in diet, losing weight, quitting smoking, and increasing physical activity. In addition, it is important for patients to avoid stressors and learn how to cope with feelings of depression and anxiety. Teaching patients to adhere to their medication regimen and monitor their health at home are also crucial. High blood pressure, diabetes, and abnormal lipid levels should be managed effectively, as they can impact the course of heart disease and increase the risk of future events.
Guided medical therapy can be split into two categories. The first involves therapies that slow the progression of atherosclerotic diseases, decrease future heart attacks, and reduce death rates over time. These medications include anti-platelet agents, beta blockers, renin-angiotensin-aldosterone system blockers, and drugs that reduce lipid levels. The second category addresses symptoms, aiming to alleviate chest pain through the use of nitrates, beta blockers, calcium channel blockers, and other new treatments.
Different drugs are recommended for preventing heart attacks and sudden cardiac death. Aspirin is most commonly used to decrease the risk of these events. However, some controversy exists over the use of aspirin for primary prevention in patients with different risk levels of coronary artery disease. Newer anti-platelet drugs like ticagrelor and prasugrel are typically not recommended for stable heart disease unless the patient has recently had a coronary event.
Beta-blockers are the only known drugs that can prevent heart attacks and affect death rates in ischemic cardiomyopathy. Existing guidelines suggest the use of beta-blockers for at least three years after a heart attack and indefinitely for those patients with reduced left ventricle function. Renin-angiotensin-aldosterone inhibitors are also recommended for patients with reduced heart function and those with other high-risk features.
Therapies to relieve symptoms typically start with beta-blockers, which are known to improve survival. If symptoms persist despite this therapy, dosage may be increased or other medicines may be added. If these measures fail, then revascularization is considered.
Revascularization aims to improve symptoms and survival. This procedure is recommended for those patients with angina that persists despite optimal medical therapy and for those who have high-risk anatomical features. The procedure involves using coronary artery bypass grafts or primary cutaneous intervention depending on the patient’s individual circumstances. However, no survival benefit has been shown in patients with single-vessel disease that does not involve the proximal left anterior descending artery.
What else can Chronic Ischemic Heart Disease Selection of Treatment Modality (Longterm Coronary Artery Disease) be?
If you are experiencing chest pain, your doctor might consider several different conditions that could be the source of your discomfort. These include:
- Acute pericarditis (inflammation of the tissue around the heart)
- Angina (chest pain due to reduced blood flow to the heart)
- Atherosclerosis (hardening and narrowing of the arteries)
- Coronary artery spasm (sudden tightening of muscles in the artery walls)
- Dilated cardiomyopathy (heart muscle disease that affects pumping)
- Familial hypercholesterolemia (genetic disorder that lead to high cholesterol levels)
- Giant cell arteritis (inflammation of arteries)
- Hypertension (high blood pressure)
- Hypertensive heart disease (heart conditions resulting from high blood pressure)
- Kawasaki disease (a rare disease in children that involves inflammation of blood vessels)
Your doctor will take into account your symptoms, medical history, and the results of any tests or scans to accurately diagnose your condition.
