Chronic Coronary Syndrome (Coronary Heart Disease)

• Chronic coronary syndrome (CCS) encompasses asymptomatic coronary atherosclerosis, symptomatic coronary heart disease as well as the disease following invasive treatment or acute coronary syndrome.
• If obstructive coronary heart disease (CHD) is suspected:
  • assess pretest probability http://www.dynamed.com/condition/coronary-artery-disease-cad#HISTORY_OF_PRESENT_ILLNESS__HPI___ANC_1475611144 and risk factors
  • examine the patient carefully
  • perform a 12-lead ECG and have the required laboratory tests done (risk factors)
  • assess the need for other investigations (see Workup here)
  • consider starting pharmacotherapy (see Pharmacotherapy here)
  • assess the urgency of investigations.
• The clinical pretest probability of CHD can be assessed based on the patient's age and sex and the type of chest pain, as well as on the number of risk factors (see Central Illustration in http://www.sciencedirect.com/science/article/pii/S0735109720373678).
• The probability of developing CHD/myocardial infarction or dying of arterial disease can be estimated using various risk calculators (e.g. SCORE 2 http://www.escardio.org/Education/Practice-Tools/CVD-prevention-toolbox/HeartScore and relevant local tools).
• If the pretest probability of CHD is very low (< 5%), other possible causes of chest pain should be individually assessed.
  • Provide instruction and guidance concerning established risk factors.
  • If difficult symptoms persist without any detectable cause, consultation of a specialist should be considered.
• If the pretest probability of CHD is low (6-15%), a prognostically significant CHD is only rarely found and diagnostic examinations should be utilized with consideration.
• If the pretest probability of CHD is increased (> 15%), the benefit of diagnostic examinations is at its highest.
• When suspecting obstructive CHD, diagnostic examinations include coronary CT angiography, (invasive) coronary angiography and demonstration of ischaemia by an exercise test or physiological imaging. The most suitable examination is selected depending on the individual situation; see picture Investigation Strategy Guidelines for a Patient with Chest Painwhen Suspecting Chronic Obstructive Coronary Heart Disease (Chd).
• Prevention is essential in the treatment of CCS, utilizing both lifestyle methods and, as necessary, prognosis-improving medication.
• The treatment of CHD consists of careful reduction of risk factors as well as symptom management by drug therapy and, if necessary, by invasive interventions.
  • Optimal drug therapy combined with lifestyle changes is crucial for the prognosis.
  • If symptoms of CHD persist despite optimal drug therapy, the patient should be referred for assessment within specialized care to assess the need for invasive interventions, if such assessment has not yet been performed or if the symptoms have increased during drug therapy.

Causes and clinical manifestation

• For the main risk factors, see table T1.
• CHD may present as stable CHD or as coronary syndrome Acute Coronary Syndrome and Myocardial Infarction.

• Obstructive atherosclerotic plaques, endothelial dysfunction, microcirculatory dysfunction and coronary artery spasm reduce blood flow in the coronary arteries thus reducing the oxygen supply to the myocardium, which, in turn, produces the typical symptom of CHD, chest pain (angina pectoris).
• Other symptoms include exertional dyspnoea, fatigue and nausea on exertion.
• For differential diagnosis of chest pain, see article Acute coronary syndrome and myocardial infarction, table Acute Coronary Syndrome and Myocardial Infarction).

Symptoms and clinical diagnosis

• Stable angina is a clinical diagnosis which indicates the repeated occurrence of chest pain, induced by an exercise level typical for the patient.
• The pain is relieved by rest and shows no great daily variation, occurring at predictable levels of exercise, i.e. when the rate-pressure product exceeds the patient's personal threshold.
• Typical angina pain
  1. starts gradually during exertion, more quickly if the exertion is sudden, and becomes worse as the exertion continues. Sometimes continuing the exertion does not increase the pain but instead brings about relief (the walk-through angina phenomenon).
     • Emotional stress may also provoke pain as the rate-pressure product increases.
  2. is felt across the chest as widespread constrictive, heavy or tight pain that may make the person slow down or stop
     • The pain may also radiate to the neck, jaw, arms, epigastric region or between the shoulder blades. The sites of radiation usually stay constant.
  3. is relieved in a few minutes by rest or glyceryl trinitrate.
• If the pain meets all three characteristics, it is highly probable that the patient has typical angina.
• If the pain only meets two of the above characteristics, the patient has atypical angina.
• Symptom of dyspnoea is equal to atypical angina as regards the pretest probability.
• If the pain only meets one or none of the above typical characteristics, the patient is likely to have non-cardiac chest pain.
  • Characteristics suggestive of non-cardiac origin include:
    • The patient's exercise tolerance is usually normal
    • Pain occurs at rest and is sharp or stabbing in nature and may last for several hours or even days
    • Tthe location of pain may vary, and the pain sites are sometimes palpable
    • Pain is associated with chest wall movements
    • Glyceryl trinitrate does not help or takes more than 10 minutes to bring pain relief.
• Grading of angina pectoris (CCS, Canadian Cardiac Society): see table T2.

Workup

• Examinations in primary health care:
  • Clinical examination (status)
  • 12-lead ECG
  • Laboratory tests
  • Chest X-ray (differential diagnosis), as necessary
  • depending on regional procedures (chains of care), additionally echocardiography.
• Further investigations include clinical exercise test Exercise Stress Test, invasive coronary angiography, myocardial perfusion scan, exercise echocardiography or coronary CT angiography. See picture Investigation Strategy Guidelines for a Patient with Chest Painwhen Suspecting Chronic Obstructive Coronary Heart Disease (Chd)..
  • Further investigations are mainly carried out in specialized care.
  • Local practices affect the selection of further investigations.
  • Coronary CT angiography is selected when the pretest probability is low.
  • Invasive coronary angiography is selected as the first-line examination when the pretest probability is high and it is likely that the examination leads to invasive treatment.

Special features in the diagnosis of CHD in women

• In women, CHD is diagnosed on average 5-10 years later than in men.
  • The incidence of CHD increases noticeably after menopause.
  • By the age of 70-79 years, the gender differences in both the incidence and the mortality due to CHD have levelled out.
• The risk factors for CHD are the same for both sexes.
  • Women who develop CHD before menopause have more risk factors than those who develop the disease at a later age.
  • If CHD develops in a middle-aged woman she is likely to have several risk factors: smoking, dyslipidaemia, diabetes, hypertension.
• It is more difficult to diagnose CHD in women than in men.
  • In women, the chest pain is more often atypical.
  • It is still particularly important to investigate the symptom carefully even if this takes more time.
  • After menopause, the diagnostic accuracy of symptoms improves. In women aged over 65-70 years, the diagnostic accuracy of chest pain is similar to that in men.
  • The predictive value of exercise testing Exercise Stress Test is lower in women. This is due to the greater number of false-positive test results in premenopausal women.
  • Coronary CT angiography is often the recommended first-line examination; see Coronary Computed Tomography Angiography (Ccta)

Management of CHD risk factors Effect of Dietary Interventions on Diet and Cardiovascular Risk Factors, Multiple Risk Factor Interventions for Primary Prevention of Coronary Heart Disease, Low Glycaemic Index Diets for Cardiovascular Disease, Reduced Saturated Fat for Preventing Cardiovascular Disease, Psychological Interventions for Coronary Heart Disease, Patient Education in the Management of Coronary Heart Disease, Mediterranean-Style Diet for the Primary and Secondary Prevention of Cardiovascular Disease, Promoting Patient Utilisation of Cardiac Rehabilitation, Music for Coronary Heart Disease Patients, Home-Based Versus Centre-Based Cardiac Rehabilitation, Yoga for Cardiovascular Disease Prevention, Homocysteine Lowering Interventions for Preventing Cardiovascular Events, Omega-3 Fatty Acids for Prevention of Cardiovascular Disease, Hormone Therapy for Preventing Cardiovascular Disease in Post-Menopausal Women

• Minimizing all risk factors has a marked effect on prognosis as it slows down the progress of atherosclerosis and prevents the development of an MI http://www.dynamed.com/evaluation/cardiac-stress-testing#EXERCISE_TESTING_CAD_DIAGNOSIS.
• Stopping smoking is very important http://www.dynamed.com/condition/cardiovascular-disease-major-risk-factors#SMOKING. The risk of an MI is 3-fold in smokers and even higher in women.
• In addition, excessive alcohol consumption should be reduced.
• Hypertension should be treated Hypertension: Investigations, Treatment Initiation and Non-Pharmacological Treatment http://www.dynamed.com/condition/cardiovascular-disease-major-risk-factors#GUID-3112316D-E710-47E5-8BA4-22A7A6C2A9A7.
  • If the patient has elevated blood pressure or established hypertension, diabetes or renal insufficiency, the target level is < 130/< 80 mmHg.
• The management of hyperlipidaemias http://www.dynamed.com/condition/cardiovascular-disease-major-risk-factors#GUID-4739BCED-E3FD-48DE-88BE-575EB28FEB71
  • Statin therapy is recommended for all patients with CHD. The dose is increased to the highest recommended dose that the patient tolerates. If required, ezetimibe may be added to the treatment. Use of PCSK9 inhibitors should be considered in very high risk cases.
  • Recommendations
    • LDL cholesterol < 1.4 mmol/l (or decreased by > 50% from the baseline value).
    • For more information on treatment goals and pharmacotherapy of hyperlipidaemias, see article Treatment of dyslipidaemias Treatment of Dyslipidaemias
• Treating obesity http://www.dynamed.com/condition/cardiovascular-disease-major-risk-factors#GUID-A7F6AC3D-6B9E-40D0-9E09-EDE6D62C6B9F
  • If the patient's BMI is higher than 28 and the waist circumference ≥ 100 cm in men, or ≥ 90 cm in women, weight reduction is indicated.
  • The goal is to achieve a BMI ≥ 25 and a waist circumference ≥ 94 cm in men and ≥ 80 cm in women.
  • Abdominal obesity (high waist-to-hip ratio) signifies a particularly high risk http://www.dynamed.com/condition/cardiovascular-disease-major-risk-factors#WAIST-TO-HIP_RATIO.
• Patients who have had an MI are often found to have a slightly increased fasting blood glucose concentration, impaired glucose tolerance or diabetes http://www.dynamed.com/condition/cardiovascular-disease-major-risk-factors#GUID-60BB896A-404C-402C-A5C0-46EF1156FBEE.
  • If the 2-hour oral glucose tolerance test is normal, fasting glucose levels should be checked at annual follow-up visits.
  • Should the glucose tolerance test results be abnormal, the patient will need exercise and dietary advice and possibly additionally medication and more frequent follow-up visits.
  • If diabetes is diagnosed, measures should be taken according to the regional chain of care.
• Physical exercise Exercise-Based Rehabilitation for Coronary Heart Disease, Daily Steps and Mortality http://www.dynamed.com/condition/cardiovascular-disease-major-risk-factors#PHYSICAL_ACTIVITY_AND_REDUCED_RISK_OF_CORONARY_EVENTS
  • Regular exercise improves not only the sense of well being but also the prognosis, by reducing risk factors. Physical activity also plays a part in primary prevention.
  • See e.g. chapter Physical activity in http://academic.oup.com/eurheartj/article/41/3/407/5556137, as well as http://pubmed.ncbi.nlm.nih.gov/34741536/ and http://pubmed.ncbi.nlm.nih.gov/33611446/.
• According to current scientific knowledge, oestrogen replacement therapy is not recommended for primary or secondary prevention http://www.dynamed.com/drug-review/hormonal-replacement-therapy-hrt-and-cardiovascular-disease#GUID-81DB16D5-BB81-44F8-B5F8-286C3820C96C. Existing hormone therapy can be continued based on individual assessment.

Pharmacotherapy: aims and modes of action

• If suspicion of symptomatic CHD arises, aspirin, a statin and a glyceryl trinitrate product for the symptoms can be started at the very first visit and, additionally, a beta-blocker if sufficient laboratory tests have been performed. The effect of the treatment is checked in a follow-up visit.

Revascularization (PCI and CABG)

• Coronary artery revascularization may be performed either by angioplasty (PCI) or by coronary artery bypass graft surgery (CABG) http://www.dynamed.com/management/management-of-stable-angina#EFFICACY_OF_CORONARY_ARTERY_BYPASS_GRAFT.
  • Coronary artery patency is sustained better with stenting than with balloon dilatation (i.e. percutaneous transluminal coronary angioplasty, PTCA) alone.
  • Drug-eluting stents are impregnated with a cell growth inhibitor that is slowly released into the surrounding tissues over several months. Drug-eluting stents have clearly reduced the frequency of restenosis compared with metal stents or PTCA alone, but drug-eluting stents may be associated with development of thrombosis.
  • A drug-eluting balloon releases a cell growth inhibitor during balloon angioplasty of an occluded coronary artery.
• The decision regarding the need for revascularization and the preferred method (PCI/CABG) is based not only on the severity, location and number of coronary occlusions but also on the assessment of left ventricular function, potential valvular diseases, severity of symptoms and comorbidity (diabetes, renal disease) and risks related to surgery.
• The advantages of PCI include the short duration of treatment, shorter recovery period and faster return back to work. The more frequent need for later repeat revascularization compared with CABG may be considered a disadvantage.
  • CABG is the recommended treatment method especially for patients with diabetes combined with multivessel disease.
• In outpatient care, after revascularization it is most important to monitor the patient's state and risk factors and to use pharmacological treatment improving the prognosis, according to the applicable guidelines. Symptom-relieving drug therapy can often be at least reduced.