Page 262 - Concise Pathology for Exam Preparation ( PDFDrive )

10 Blood Vessels 247

Neural factors
• Sodium levels
• Mineralocorticoids
• Atrial Natriuretic Peptide (ANP)
Constrictors Dilators
(α-adrenergics) (β-adrenergics)

Blood pressure = Cardiac output × Peripheral resistance

• Heart rate Humoral factors
• Contractility

Constrictors Dilators
• Angiotensin II • Prostaglandins
• Catecholamines • Kinins
• Thromboxane • No
• Leukotrienes
FLOWCHART 10.5. Role of cardiac output and peripheral resistance in regulation of blood
pressure.

Effects of Hypertension

The major effects of systemic hypertension are noted in the following organs:
• Heart
• Blood vessels
• Kidneys
• CNS
• Retina
Effects on Heart (Hypertensive Heart Disease)
• Usually seen in association with systemic hypertension of prolonged duration, and is the
second most common form of heart disease after IHD.
• Death in hypertensive patients is due to congestive heart failure, IHD, cerebrovascular
accident (stroke) and renal failure.
Pathogenesis (Flowchart 10.6):

Increased peripheral vascular resistance due to persistent hypertension

Increased impedance to ventricular emptying

Pressure overload in left ventricle

Left ventricular hypertrophy
Increase in afterload beyond compensatory capacity of left
ventricle (LV)
LV dilatation with hypertrophy (eccentric hypertrophy)
FLOWCHART 10.6. Pathogenesis of hypertensive heart disease.

Gross pathology: Marked hypertrophy of the heart, chiefly left ventricle
Microscopic findings: Enlargement and degeneration of myocardial fibres with areas of
myocardial fibrosis

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