Atherosclerotic angina

Heart rate Heart rate eontributes to time-integrated fiber tension because at fast heart rates, fibers spend more time at systolic tension levels. Furthermore, at faster rates, diastole is abbreviated, and diastole eonstitutes the time available for coronary flow (coronary blood flow is low or nil during systole). Systolic blood pressure and heart rate may be multiplied to yield the double product, a measure of eardiae work and therefore of oxygen requirement. In patients with atherosclerotic angina, effective drugs reduce the double product. 

A. Classification and Mechanism of Action These drugs are described in detail in Chapter 10. All beta-blockers are effective in the prophylaxis of atherosclerotic angina attacks. 

Myocardial revascularization by coronary artery bypass grafting (CABG) and percutaneous transluminal coronary angioplasty (PTCA) have become important in the treatment of severe angina. These are the only methods capable of consistently increasing coronary flow in atherosclerotic angina and increasing the double product. 

TABLE 4-1. Non-atherosclerotic Conditions that Can Cause Angina-like Symptoms ... 

The hallmark feature in the pathophysiology of chronic stable angina is an established atherosclerotic plaque that impedes... 

Endothelial dysfunction, inflammation, and the formation of fatty streaks contribute to the formation of atherosclerotic coronary artery plaques, the underlying cause of coronary artery disease (CAD). The predominant cause of ACS, in more than 90% of patients, is atheromatous plaque rupture, Assuring, or erosion of an unstable atherosclerotic plaque that occludes less than 50% of the coronary lumen prior to the event, rather than a more stable 70% to 90% stenosis of the coronary artery.3 Stable stenoses are characteristic of stable angina. 

In patients treated for secondary intervention, symptoms of atherosclerotic cardiovascular disease, such as angina or intermittent claudication, may improve over months to years. Xanthomas or other external manifestations of hyperlipidemia should regress with therapy. 

Goal BP values are <140/90 for most patients, but <130/80 for patients with diabetes mellitus, significant chronic kidney disease, known coronary artery disease (myocardial infarction [MI], angina), noncoronary atherosclerotic vascular disease (ischemic stroke, transient ischemic attack, peripheral arterial disease [PAD], abdominal aortic aneurysm), or a 10% or greater Framingham 10-year risk of fatal coronary heart disease or nonfatal MI. Patients with LV dysfunction have a BP goal of <120/80 mm Hg. 

Because the most common cause of angina is atherosclerotic disease of the coronaries (CAD), therapy must address the underlying causes of CAD as well as the immediate symptoms of angina. In addition to reducing the need for antianginal therapy, such primary management has been shown to reduce major cardiac events such as myocardial infarction. 

Demrow et al. (1995) used the Folts model of unstable coronary stenosis, which closely mimics ruptured atherosclerotic plaque, causing unstable angina, to examine the effects of grape juice on platelet function in vivo. In this model,... 

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