HYPERTENSIVE HEART DISEASE (Hypertensive cardiomyopathy) H.A MWAKYOMA, MD

HHD DEFINITION: Is the disease of the heart resulting from systemic hypertension of prolonged duration and manifesting by left ventricular hypertrophy Or Is the response of the left ventricle to increased peripheral resistance due to increased systemic arterial pressure

Systemic Hypertensive Heart Disease: Hypertensive heart disease is an important and common form of heart disease. Features: - Patient has a history of hypertension. - Left ventricular hypertrophy, concentric type. - Absence of other lesions that might induce cardiac hypertrophy. Eg: Aortic valve stenosis

HHD Hypertension predisposes to atherosclerosis Most patients of HHD have advanced coronary atherosclerosis and my develop progressive IHD

Definition of HTN CATEGORY SYSTOLIC BP DIASTOLIC BP normal < 120 and < 80 Pre-HTN 120-139 or 80-89 Hypertension Stage 1 140-159 or 90-99 Stage 2 ≥ 160 or ≥ 100

TYPES OF HYPERTENSION SYSTOLIC AND DIASTOLIC Primary(Essential, Idiopathic) Secondary Renal: Acute GN, Diabetic Nephropathy Endocrine: TSH, cortisol, calcium aortic coarctation pregnancy-induced neurologic: tumor, sleep apnea stress: surgery, burns, EtOH withdrawal,S.cell Drugs: decongestants, antidepressants, OCP

ESSENTIAL HYPERTENSION Most common HBP( > 90 %)--multifactorial increased peripheral resistance perpetuates the process of high blood pressure and all of its secondary effects structural hypertrophy giving rise to smooth muscle hypercontractility pressure varies throughout the day major risk factor for coronary, renal, and cerebrovascular disease carries prognostic value: 16X increased risk 40 years of smoke

HYPERTENSION WITH AGE Systolic BP rises continuously with age Diastolic rises up to age 50, then falls Pulse pressure then widens with age

Pathogenesis: There is myocytic hypertrophy in response to the increased work. (pressure load in systemic hypertension) The stress of pressure on the ventricular wall causes increased production of:- Myofilaments Myofibrils Other cell organelles and Nuclear enlargement Since the the adult myocardial fibres do not divide, the fibres are hypertrophied

Pathogenesis:--cont--- Thickened myocardium reduces left ventricle compliance, impairing diastolic filling. Individual myocyte hypertrophy increases the distance for oxygen and nutrient diffusion from adjacent capillaries. In a significant number of patients there is associated coronary atherosclerosis accompanying hypertension which may further lead to ischemia

TARGET ORGAN DAMAGE Left Ventricular Hypertrophy End result of hypertensive heart disease structural adaptation to pressure overload initially adaptive and later pathologic mass >100-130 g/m2

PATHOLOGIC CHANGES: Thickened left ventricle wall. The left ventricle wall thickness is usually more than 2cm wall thickness. (NORMAL 1.3cm – 1.5cm) increased heart weight. The average heart weight is 500 to 600 gm. It may be as much as 1100gm. The papillary muscle and trabeculae carneae are rounded and prominent and cardiac chamber is small (concentric hypertrophy).

PATHOLOGIC CHANGES:--cont-- When cardiac failure ensues, dilatation of the chamber also may be prominent. Endocardial fibrous thickening may be present in the left ventricle in instances of long-standing hypertension. After the onset of left ventricular failure, there may be dilatation and hypertrophy of the right side of the heart

Hypertensive Heart Diseases

Left Ventricular Hypertrophy:

HHD Microscopic features: Myocytes and nuclei are enlarged. In long-term cases diffuse interstitial fibrosis and focal myocyte atrophy and degeneration may develop, with left ventricle chamber dilatation and wall thinning. Myocardial edema and foci of necrosis characterized either by intense eosinophilia or by complete dissolution of the muscle fibers occur in malignant hypertension

HHD FATE: Patients die of congestive heart failure ; Complications of coronary artery disease, such as myocardial infarction can occur ; There is increased risk of sudden death ;  Some patients die of renal disease, stroke etc. ; Fibrinous pericarditis may be evident in patients who die as a result of uraemia  ; Therapeutic control of pressure may, lead to regression of the enlarged myocytes and reduction of heart size