Hypertensive heart disease (HHD), a result of long-standing hypertension, is characterized by changes in the myocardial structure and function in the absence of other primary cardiovascular abnormalities. It is the No. 1 cause of death associated with high blood pressure. The definition includes heart failure and other cardiac complications of hypertension. In 2013 hypertensive heart disease resulted in 1.07 million deaths as compared with 630,000 deaths in 1990 in the US.
Hypertension or high blood pressure affects at least 4 billion people worldwide. Hypertensive heart disease is only one of several diseases attributable to high blood pressure. Other diseases caused by high blood pressure include ischemic heart disease, stroke, peripheral arterial disease, aneurysms and kidney disease. Hypertension increases the risk of heart failure by two or three-folds and probably accounts for about 25% of all cases of heart failure. In addition, hypertension precedes heart failure in 90% of cases, and the majority of heart failure in the elderly may be attributable to hypertension. Hypertensive heart disease was estimated to be responsible for 1.0 million deaths worldwide in 2004 (or approximately 1.7% of all deaths globally), and was ranked 13th in the leading global causes of death for all ages.
An increase in peripheral vascular resistance, the hallmark of established hypertension, alters wall stress in the left ventricle. Concentric LVH is the consequence of the neutralization of wall stress associated with increased impedance to ventricular emptying. The increase in wall thickness follows the law of Laplace. Wall stress stimulates sarcomeres to proliferate in parallel by increasing protein synthesis, which increases myocyte width. The net effect is an increase in the wall thickness/chamber dimension or relative wall thickness. However, when hypertrophy can no longer compensate for the increased afterload, then LV dilatation (eccentric hypertrophy) occurs and LV performance decreases. Ambulatory blood pressure (BP) correlates better with LVH than BP measured at a single visit or multiple office visits. However, a single ambulatory BP cannot assess the total impact of BP over months or years. However, despite the lack of long durations of assessment of BP, other nonhemodynamic variables, including body mass index, age, physical activity, sodium, parathyroid hormone, growth hormone, thyroid hormone, thyroid-stimulating hormone, norepinephrine, renin, aldosterone, angiotensin II, intracellular calcium, atrial natriuretic peptide, blood viscosity, and arterial compliance correlate with LVH. In addition, other factors, such as obesity, can modify the heart’s response to pressure overload.
The symptoms and signs of hypertensive heart disease will depend on whether or not it is accompanied by heart failure. In the absence of heart failure, hypertension, with or without enlargement of the heart (left ventricular hypertrophy) is usually asymptomic.
Symptoms, signs and consequences of Congestive heart failure can include:
Heart failure can develop insidiously over time or patients can present acutely with acute heart failure or acute decompensated heart failure and pulmonary edema due to sudden failure of pump function of the heart. Sudden failure can be precipitated by a variety of causes, including myocardial ischemia, marked increases in blood pressure, or cardiac arrhythmias.
Other conditions can share features with hypertensive heart disease and need to be considered in the differential diagnosis. For example:
Others include: CBC, FBS, FLP, E&U, CR, ABG
K+ retaining Diuretics
ACE inhibitors eg Captopril, Lisinopril, Ramipril
Angiotensin II antagonists eg Losartan, Valsartan, Candesartan
Direct vasodilators eg Hydralazine