Heart in hypertension

Dr Tapan Ghose

The relationship between heart and body circulation is analogous to the central pumping station of water supply and distribution system. Whenever multiple blocks develop in the distribution system, the central pumping station (heart) is affected. Normal size of the heart is close to one’s closed fist. The normal thickness of the walls of the heart in 6 to 11mm, depending on age and gender. When the thickness is more on the left side, it is called left ventricular hypertrophy (LVH) and vice versa. Normal weight of the heart ranges from 200 to 400 g, depending on gender and body surface area. When the weight is more, it is called increased Left Ventricular Mass (LVM).
Whenever the blood pressure remains elevated for more than six months, heart muscles start showing LVH or increased LVM. This is exactly like prominent muscles seen in persons performing regular weightlifting. Structural and biological changes in heart resulting from high blood pressure are encompassed by the term ‘hypertensive heart disease’.
Untreated high blood pressure is related to LVH, increase in LV mass, heart failure, cardiac rhythm disturbances, ischemic heart (coronary) disease and sudden death.
LVH or high LV mass is a result of increase in the work burden of heart muscle cells. The cell becomes larger. Increased thickness results in impaired relaxation of heart muscle. Heart muscles becomes stiff. As a result the physiological low blood pressures inside the heart chambers become high. One gets difficulty in climbing up or walking fast. This may lead to a type of heart failure called heart failure with preserved systolic function. The pumping is fine, only the filling is abnormal. Gradually, the pumping function also becomes abnormal and we call it heart failure with reduced systolic function. Heart failure risk is 10 times in hypertension with LVH.
Some individuals develop extra beats which are felt as a thump or missing beats. Sometimes the upper chamber (atrium) enlarges which result in irregular heart rhythm (atrial fibrillation). This can cause formation and dislodgement of blood clot from the upper chamber of heart and blockage in blood supply of any part of brain. This results in stroke.
Coronary Artery Disease (CAD) develops in patients with hypertension at a frequency which is two times more than the general population. Silent heart attack, larger size of heart damage and higher complications are seen in hypertension with CAD.

• Hypertension causes accelerated rate of arterial blockage. The flow of blood is also abnormal.
• Hypertension increases the risk of sudden death by 2.5 times. This is mainly due to higher incidence of Coronary artery disease (acute heart attack) which results in fatal arrhythmia.

The good part is that it is a preventable illness. Both non drug therapy and drug therapy in consultation with a physician helps control blood pressure. One must understand that this is not a curable illness. One can control blood pressure with non-drug therapy and drug therapy. BP should be treated to the target range. Good control of blood pressure will prevent or reverse many changes in heart. This will reduce stroke, heart failure hospitalisation and death.
Our ultimate aim should be to avoid high blood pressure development (primordial prevention). The tips for this are:
(1) No extra salt diet
(2) Consume 600 g of fruits and vegetables daily
(3) Maintain ideal body weight
(4) Moderate intensity exercise daily for 30-35 minutes along with yoga and meditation
(5) Sleep seven hours daily
(6) Finally, don’t worry, be happy.

Dr Ghose is Director & Head, Cardiology and Director, Clinical Research &
Academics,Fortis Flt Lt Rajan Dhall Hospital, Vasant Kunj, New Delhi