Stable Angina Flashcards
What is the most common cause of myocardial ischemia?
Atherosclerotic disease of an epicardial coronary artery (or arteries)
Powerful risk factors for IHD
Obesity
insulin resistance
type 2 diabetes mellitus
Major determinants of myocardial oxygen demand (MVO2)
Heart rate
Myocardial contractility
Myocardial wall tension (stress)
Blood flows through the coronary arteries in a phasic fashion, with the majority occurring during ____.
diastole
Coronary resistance occurs in three sets of arteries:
_____(R1)
Prearteriolar vessels (R2)
Arteriolar and intramyocardial capillary vessels (R3)
Large epicardial arteries
In the absence of significant flow-limiting atherosclerotic obstructions, R 1 is trivial; the major determinant of coronary resistance is found in __
R2 and R3
The normal coronary circulation is dominated and controlled by the heart’s requirements for _____
oxygen
The major site of atherosclerotic d ease.
Epicardial coronary arteries.
What are the major risk factors for atherosclerosis?
High levels of plasma low-density lipoprotein (LDL)
Cigarette smoking
Hypertension
Diabetes mellitus
nomal functions of the vascular endothelium
local control of vascular tone
maintenance of an antithrombotic surface
and control of inflammatory cell adhesion and diapedesis.
There is also a predilection for atherosclerotic plaques to develop at sites of increased turbulence in coronary flow, such as at branch points in the ___
epicardial arteries.
Critical obstructions in vessels, such as the ____ and the ____ coronary artery, are particularly hazardous.
left main coronary artery
proximal left anterior descending
Transient T-wave inversion probably reflects ____
nontransmural, intramyocardial ischemia
Transient ST-segment depression often reflects ___
patchy subendocardial ischemia;
ST-segment elevation is thought to be caused by more severe ____
transmural ischemia
The typical patient with angina
man >50 years or a woman >60 years of age who complains of episodes of chest discomfort, usually described as heaviness, pressure, squeezing, smothering, or choking and only rarely as frank pain
Hand over the sternum, s times with a clenched fist, to indicate a squeezing, central, substernal discomfort
(Levine’s sign)
Angina is usually ____ in nature (typically with the severity of the discomfort not at its most intense level at the outset of symptoms), typically lasts ____, and can radiate to either ___ (especially the ulnar aspects of the forearm and hand). It also can arise in or radiate to the back, interscapular region, root of the neck, jaw, teeth, and epigastrium.
crescendo-decrescendo
2–5 min
shoulder and to both arms
may be due to episodic tachycardia, diminished oxygenation as the respiratory pattern changes during sleep, or expansion of the intrathoracic blood volume that occurs with recumbency; the latter causes an increase in cardiac size (end-diastolic volume), wall tension, and myocardial oxygen demand that can lead to ischemia and transient LV failure.
Nocturnal angina
Exertional angina typically is relieved in ___ by slowing or ceasing activities and even more rapidly by rest and sublingual nitroglycerin
1–5 min
sublingual nitroglycerin
Anginal “equivalents” are symptoms of myocardial ischemia other than angina. They include _______ and are more common in the elderly and in diabetic patients.
dyspnea, nausea, fatigue, and faintness
A particularly challenging problem is the evaluation and management of patients with persistent ischemic-type chest discomfort but no flow-limiting obstructions in their epicardial coronary arteries. This situation arises more often in women than in men. Potential etiologies include ____(detectable on coronary reactivity testing in response to vasoactive agents such as intracoronary adenosine, acetylcholine, and nitroglycerin) and ____.
microvascular coronary disease
abnormal cardiac nociception.
Auscultation can uncover arterial bruits, a third and/or fourth heart sound, and, if acute ischemia or previous infarction has impaired papillary muscle function, an apical systolic murmur due to mitral regurgitation. These auscultatory signs are best appreciated with the patient in the ____position.
left lateral decubitus
Tenderness of the chest wall, localization of the discomfort with a single fingertip on the chest, or reproduction of the pain with palpation of the chest makes it unlikely that the pain is caused by myocardial ischemia.
True
Evidence exists that an elevated level of high-sensitivity ____ (specifically, between 1 and 3 mg/L) is an independent risk factor for IHD and may be useful in therapeutic decision-making about the initiation of hypolipidemic treatment.
C-reactive protein (CRP)
A positive result on exercise indicates that the likelihood of CAD is 98% in males who are >50 years with a history of typical angina pectoris and who develop chest discomfort during the test.
True
Obstructive disease limited to the circumflex coronary artery may result in a ___stress test since the posterolateral portion of the heart that this vessel supplies is not well represented on the surface 12-lead ECG.
false-negative
Modified (heart rate–limited rather than symptom-limited) exercise tests can be performed safely in patients as early as __ days after uncomplicated myocardial infarction
6
Contraindications to exercise stress testing include r___
rest angina within 48 h, unstable rhythm, severe aortic stenosis, acute myocarditis, uncontrolled heart failure, severe pulmonary hypertension, and active infective endocarditis.
Failure of the blood pressure to increase or an actual decrease with signs of ischemia during the exercise stress test is an important adverse prognostic sign, since it may reflect ___
ischemia-induced global LV dysfunction.
Exercise Stress Test Discontinued on symptoms or specific signs: __
chest discomfort, shortness of breath, dizziness, severe fatigue, ST-segment depression >0.2 mV, drop in systolic BP >10 mmHg, or ventricular tachyarrhythmia.
The principal prognostic indicators in patients known to have IHD are ____
age, the functional state of the left ventricle, the location(s) and severity of coronary artery narrowing, and the severity or activity of myocardial ischemia.
Angina Characteristics Indicating Higher Risk or coronary events
Recent-onset or unstable angina
Post-myocardial infarction angina
Angina unresponsive to medical therapy
Angina with congestive heart failure symptoms
Most important, any of the following signs during noninvasive testing indicates a high risk for coronary events:
Inability to complete 6 minutes (Stage II) on Bruce protocol exercise test
Strongly positive exercise test:
Onset of ischemia at low workloads
≥0.1 mV ST-segment depression before Stage II or ≥0.2 mV at any stage
Persistent ST-segment depression >5 minutes post-exercise
Systolic pressure drop >10 mmHg or ventricular tachyarrhythmias during exercise
On cardiac catheterization, elevations of ___ and ___ and reduced ____are the most important signs of LV dysfunction and are associated with a poor prognosis.
LV end-diastolic pressure
ventricular volume
ejection fraction
Obstructive lesions of the ___ (>50% luminal diameter) or ____coronary artery proximal to the origin of the first septal artery are associated with a greater risk than are lesions of the right or left circumflex coronary artery because of the greater quantity of myocardium at risk.
left main
left anterior descending
With any degree of obstructive CAD, mortality is greatly increased when ____is impaired; conversely, at any level of LV function, the prognosis is influenced importantly by the quantity of myocardium perfused by critically obstructed vessels
LV function
The greater the number and severity of risk factors for coronary atherosclerosis , the worse the prognosis of an angina patient.
What are the risk factors?
advanced age [>75 years]
hypertension
dyslipidemia
diabetes
morbid obesity
accompanying peripheral and/or cerebrovascular disease
previous myocardial infarction
In addition, obesity often is a accompanied by three other risk factors: ____
diabetes mellitus
hypertension
and hyperlipidemia.
A diet low in ____and a reduced caloric intake to achieve optimal body weight are a cornerstone in the management of chronic IHD.
saturated and trans-unsaturated fatty acids
_____ accelerates coronary atherosclerosis in both sexes and at all ages and increases the risk of thrombosis, plaque instability, myocardial infarction, and death.
Cigarette smoking
There is evidence that long-term effective treatment of ____ can decrease the occurrence of adverse coronary events
hypertension
____accelerates coronary and peripheral atherosclerosis and is frequently associated with dyslipidemia and increases in the risk of angina, myocardial infarction, and sudden coronary death.
Diabetes mellitus
Aggressive control of the dyslipidemia (target LDL cholesterol __ mg/dL) and hypertension (blood pressure ___ mmHg) that are frequently found in diabetic patients is highly effective and therefore essential
<70
<130/80
Nearly always, ____are required and can lower LDL cholesterol (25–50%), raise HDL cholesterol (5–9%), and lower triglycerides (5–30%).
HMG-CoA reductase inhibitors (statins)
Used to lower triglycerides, especially when elevated.
Fibrates, Niacin, and Icosapent Ethyl
To minimize the effects of nitrate tolerance, the minimum effective dose should be used and a minimum of___each day kept free of the drug to restore any useful response(s).
8 h
__ improve exercise tolerance in patients with chronic angina and relieve ischemia in patients with unstable angina as well as patients with Prinzmetal’s variant angina
Nitrates
They reduce myocardial oxygen demand by inhibiting the increases in heart rate, arterial pressure, and myocardial contractility caused by adrenergic activation.
B blockers
The therapeutic aims include relief of angina and ischemia.
B blockers
These drugs also can reduce mortality and reinfarction rates in patients after myocardial infarction and are moderately effective antihypertensive agents.
B blockers
Relative contraindications to beta blockers include ____
asthma and reversible airway obstruction in patients with chronic lung disease, atrioventricular conduction disturbances, severe bradycardia, Raynaud’s phenomenon, and a history of mental depression.
Beta blockers with relative β1 -receptor specificity such as ___ and ___ may be preferable in patients with mild bronchial obstruction and insulin-requiring diabetes mellitus.
metoprolol
atenolol
____(Table 273-6) are coronary vasodilators that produce variable and dose-dependent reductions in myocardial oxygen demand, contractility, and arterial pressure.
Calcium channel blockers
They are indicated when beta blockers are contraindicated, poorly tolerated, or ineffective.
Calcium channel blockers
Variant (Prinzmetal’s) angina responds particularly well to calcium channel blockers (especially members of the __ class),
dihydropyridine
Dihydropyridine vs. Nondihydropyridine
May cause bradyarrhythmias and negative inotropic effects, increasing risk of LV failure, especially in patients with LV dysfunction or on beta blockers.
Nondihydropyridine
Dihydropyridine vs. Nondihydropyridine
Strong vasodilators with lower risk of bradyarrhythmias; preferred in angina and hypertension management.
Dihydropyridine
Combination of this CCB with beta blocker
Generally should not be combined due to risk of adverse effects on heart rate and contractility.
Verapamil
Combination of this CCB with beta blocker
Complementary effects; amlodipine decreases blood pressure and dilates coronary arteries, while beta blockers slow heart rate and reduce contractility.
Amlodipine
Calcium channel blockers are indicated in patients with the following:
(1) inadequate responsiveness to the combination of beta blockers and nitrates; many of these patients do well with a combination of a beta blocker and a dihydropyridine calcium channel blocker; (2) adverse reactions to beta blockers such as depression, sexual disturbances, and fatigue; (3) angina and a history of asthma or chronic obstructive pulmonary disease; (4) sick-sinus syndrome or significant atrioventricular conduction disturbances; (5) Prinzmetal’s angina; or (6) symptomatic peripheral arterial disease.
Irreversibly inhibits platelet cyclooxygenase, reducing platelet activation.
Aspirin
Blocks P2Y₁₂ ADP receptor–mediated platelet aggregation.
Clopidogrel
Chronic administration of 75–325 mg orally per day has been shown to reduce coronary events in asymptomatic adult men over age 50, patients with chronic stable angina, and patients who have or have survived unstable angina and myocardial infarction.
Aspirin
Alternative for patients who cannot tolerate aspirin due to side effects.
Combined with aspirin, it reduces death and ischemic events in acute coronary syndrome (ACS) and lowers thrombus risk in stent implantation.
Clopidogrel
A specific sinus node inhibiting agent that may be helpful for preventing cardiovascular events in patients with IHD who have a resting heart rate ≥70 beats/ min (alone or in combination with a beta blocker) and LV systolic dysfunction.
Ivabradine
Not cost-effective for IHD patients with normal LV function who have achieved BP and LDL goals, as routine use does not lower event incidence.
ACE Inhibitors
Beneficial for chronic angina patients who continue to experience symptoms despite standard medical therapy.
Ranolazine
Inhibits the late inward sodium current (INa), reducing Na and Ca overload in ischemic myocytes.
Ranolazine
Initially for diabetes management, now with cardiovascular and renal protective effects.
SGLT2 Inhibitors
Promotes weight loss, lowers blood pressure, and reduces plasma volume.
Reduces intraglomerular hypertension and hyperfiltration, beneficial for patients with reduced LV ejection fraction, with or without diabetes.
SGLT2 Inhibitors
Reduces intracellular calcium by opening ATP-sensitive potassium channels.
Nicorandil
The most common clinical indication for PCI is ____
symptom-limiting angina pectoris, despite medical therapy, accompanied by evidence of ischemia during a stress test.
T/F
in patients with stable exertional angina, clinical trials have confirmed that PCI does not reduce the occurrence of death or myocardial infarction compared to optimum medical therapy.
T
T/F
PCI can be used to treat stenoses in native coronary arteries as well as in bypass grafts in patients who have recurrent angina after CABG.
T
PCI or CABG
Preferred for one- or two-vessel stenoses, selected three-vessel cases, and sometimes in left main disease depending on patient suitability and operator skill.
PCI
PCI or CABG
Patients with left main coronary artery stenosis, three-vessel disease (especially with diabetes or LV dysfunction), are better candidates for ___.
CABG
It is usual clinical practice to administer oral ___ indefinitely and a P2Y 12 antagonist for 1–3 months after the implantation of a bare metal stent.
aspirin
___ should be administered indefinitely and a P2Y 12 antagonist daily (dual antiplatelet therapy [DAPT]) for at least __ year after implantation of a drug-eluting stent. Evidence exists of a benefit of continuing DAPT for up to 30 months, albeit at the cost of a higher risk of bleeding.
Aspirin
1 year
When directly compared in patients with diabetes or three-vessel or left main CAD, ___ was superior to ___ in preventing major adverse cardiac or cerebrovascular events over a 12-month follow-up.
CABG was superior to PCI
Indications for CABG usually are based on
severity of s toms
coronary anatomy
and ventricular function
Associated with a higher perioperative mortality rate in CABG
Congestive heart failure and/or LV dysfunction
advanced age (>80 years)
reoperation
urgent need for surgery
and the presence of diabetes mellitus
PCI or CABG
Two-vessel disease with proximal left anterior descending artery involvement
CABG
