The cardiovascular system is composed of heart, arterials, capillaries and veins. It is the structure foundation for keeping blood circulation, material exchanges between blood and tissue and transmitting information of body fluid. The structure changes of cardiovascular system will be responsible for the functional changes that disturb whole and/or local blood circulation. The disorders of cardiovascular system affect the human health and life and are a leading cause of death in the world. In this chapter, we will mainly discuss the commonest diseases of heart and arterials, including ①degenerative vascular disorders including atherosclerosis, hypertension; ②ischemic heart disease including myocardial infarction, angina pectoris and sudden death; ③myocarditis and cardiomyopathy；④diseases of the pericarditis；⑤rheumatic fever；⑥infective endocarditis；⑦disorder of cardiac valves including mitral stenosis, mitral regurgitation, aortic stenosis and aortic regurgitation.), and so on.
- Arteriosclerosis is an imprecise term meaning thickening and loss of elasticity of the arteries caused by any condition, and its commonest types are atherosclerosis(AS),monckeberg’s medial calcification and arteriolosclerosis (arteriolar sclerosis). AS is a disease of large and medium- sized arteries that results in the progressive accumulation within the intima of smooth muscle cells and lipids. The lesion of AS includes fatty streak, fibrous plaque and atheromatous plaque, and the complicated lesions are plaque rupture and hemorrhage in plaque, thrombosis, dystrophic calcification, ulceration, aneurysm formation, neovasculerization and thinning of the underlying tunica and media. The major complications of AS include ischemic heart disease, myocardial infarction, stroke and gangrene of the extremities.
- Hypertension is a disease largely of the vasculature and as a systolic pressure greater than 160 mmHg or a diastolic pressure greater than 90 mmHg, or both. Hypertension can be classified into two main types： (1) primary (essential) hypertension, in which subtypes are benign and malignant(accelerated) hypertension； (2) secondary hypertension. There are pathological changes of vasoconstriction, thickening of the media, hyaline degeneration and intimal fibrosis in benign hypertension and fibrinoid necrosis of the media with marked intimal fibrosis and extreme narrowing of the arteriole in malignant hypertension.
- Aneurysm is a abnormal localized, permanent dilatation of an artery caused by a congenital or acquired weakness in the media. Aneurysms are classified by location, configuration, and etiology. Types of aneurysm are true and false aneurysms. There are fusiform, saccular, berry, dissecting aneurysm and arteriovenous aneurysm.
- Ischaemic heart disease (IHD) is caused by a reduction or cessation of the blood supply to the myocardium (myocardial ischaemia). IHD results in four main syndromes： ① stable angina； ② unstable angina； ③ myocardial infarction (MI)； ④ sudden cardiac death. Angina pectoris(AP) is episodic chest pain caused by ischaemia of the myocardium. MI is patchy foci of necrosis of the myocardium as a result of severe ischaemia. Types of MI are regional and diffuse MI. The site of MI depends on which vessel is involved and the majority of infarcts affect the left ventricle and septal region. Sudden cardiac death is the most important immediate consequence of myocardial ischaemia and is usually due to ventricular fibrillation.
- Rheumatic fever (RF) is a multisystem disease and an acute, often recurrent, inflammatory disease principally of children that generally follows a pharyngeal(but not skin) infection with group A beta-hemolytic streptococci. RF is a systemic disorder affecting: ①heart: pericarditis, myocarditis, and endocarditis; ②joint: polyarthritis; ③skin: subcutaneous nodules and erythema; ④arteries: arteritis. Aschoff bodies constitute foci of fibrinoid necrosis surrounded by lymphocytes, macrophages, an occasional plasma cell, and plump “activated” histiocytes called Anitschkow cells or Aschoff cells. Lesions stimulate fibroblast proliferation and lead to scarring.
- Heart valve disease are characterized principally by valvular involvement and disfunction. The functional disturbances engendered by valvular disease are stenosis and insufficiency. Stenosis is the failure of a valve to open completely, thereby impeding forward flow. Insufficiency or regurgitation, in contrast, results from failure of a valve to close completely, thereby allowing reversed flow. Both types may coexist in one valve but one type is usually dominant.
- Infective endocarditis(IE) is characterized by colonization or invasion of the heart valves or the mural endocardium by a microbiologic agent, leading to the formation of bulky, friable vegetations laden with organisms. Traditional IE has been classified on clinical grounds into acute and subacute forms. Both rheumatic heart disease and infective endocarditis are common topics in examinations.