Drugs for the weak heart!

ImageWeak Heart is a condition caused by weakness of the heart muscle where in the heart is unable to pump blood to meet the daily requirement of the body.

This condition in medical terms is called Cardiomyopathy or Left ventricular (LV) dysfunction.

This condition causes breathless on exertion initially and then breathlessnes at rest in the late stages. One is unable to sleep supine at night due to the breathlessness. It may be associated with cough and swelling of the feet. This clinical condition is called Heart Failure.

The condition is diagnosed by carrying out an Ultrasound of the heart to know its pumping function. This test is also called 2D-Echocardiography.

 

There are some important medications which patients need to take:

1. Diuretics: These are drugs given either orally or intravenously. These act on the kidneys by flushing water and electrolytes from the body. By flushing out water from the body, these drugs reduce the congestion in the lungs and thereby reduce breathlessness. They also cause reduction in the swelling in the feet. This causes increase in the urine output. Thus, these drugs are advised to be taken in the mornings. 

The common ones used are Furosemide, Spironolactone, Amiloride, Triamterene etc.

These can cause electrolyte imbalance and dehydration and so the therapy need to be monitored.

These drugs are recommended to patients in heart failure who are breathless and develop swelling of the feet. They relieve patients of their symptoms but are not found to reduce the  long term mortality.

 

2. ACE Inhibitors. This is a class of drug which acts by blocking the conversion of angiotensin I to angiotensin II. They, therefore, lower arterial resistance and increase venous capacity; increase cardiac output. They reduce the cardiac mortality in the long run and are recommended in all patients with heart failure and LV dysfunction.

The common ones used are Enalapril, Captopril, Ramipril and Perindopril. These drugs can cause increased potassium levels in the blood and can cause dry cough in come patients. If a patient in unable to tolerate the drug due to dry cough, they can be substituted with ARBs. ARBs (angiotensin receptor blockers) are similar drugs but tend to be more expensive.

They are recommended for all patients with LV dysfunction and/or heart failure as they reduce long term mortality.

 

3. Beta-Blockers: This is a class of drug which reduces sympathetic over-activity. Thereby, they reduce the heart rate and blood pressure, thus giving the heart much needed rest to recover. 

The drugs approved for this condition are Metoprolol,  Bisoprolol and Carvedilol. These drugs need to be started in very small doses and then increased carefully as some of the patient may encounter worsening of their symptoms. Majority of the patients tolerate them well. They need to be monitored for the side effects like bronchospasm and slow heart rate.

They are recommended for all patients with LV dysfunction and/or heart failure as they reduce long term mortality.

Now you know what to take if someone suffers from LV dysfunction or heart failure. 

Take care!

Heart Failure

Introduction:

Heart Failure (HF) continues to be a major heart problem and an important cause of hospitalization in India. The number of patients with HF has been gradually increasing due to improving life span of patients and improved survival after heart attacks in the last few years. More patients are being saved from heart attacks due to better availability of drugs and immediate revascularization of the blocked vessels. Though this is heartening news, the number of patients with poor heart function has been increasing all over the country.

What is Heart Failure?

Heart Failure does not mean that heart has stopped working or is about to stop working. HF is a condition in which the heart becomes so weak that it has trouble pumping a normal amount of blood carrying enough oxygen and nutrients to meet the body’s needs.

 

What causes HF?

HF develops either as a result of (1) damage to the heart muscle (which could be caused by coronary artery disease,  infection or toxic exposure to chemicals such as alcohol and drugs) or (2) when too much strain is placed on the heart because of years of untreated high blood pressure or an abnormal heart valve.

 

What is the commonest cause of Heart Failure/ heart muscle damage?

The commonest cause of HF is coronary artery disease where in the blockages of the coronary arteries cause damage to the heart muscle thereby reducing the pumping of the heart. The loss of pumping function of the heart is directly related to how fast the patient seeks treatment for a heart attack. Patients who receive treatment within one hour of onset of chest pain due to a heart attack do well as the heart muscle is salvaged from further damage due to early intervention in the form of drug treatment or angioplasty. Damage to the heart muscle due to drugs, alcohol or infections is the second common cause of HF.

 

What do the patients complain of?

The commonest symptom is shortness of breath, also called dyspnea, which is caused by accumulation of fluid in the lungs due to failure of the left side of the heart.

Swelling of feet, ankles, legs and abdomen due to accumulation of fluid is caused by failure of the right side of the heart.

Chronic cough, loss of appetite and fatigue are some of the symptoms which patients experience.

Some of the patients may complain of palpitations which may be caused by irregular heart beats.

 

Diagnosis of HF:

Patients are mostly diagnosed by their physicians due to their typical symptoms and then advised to undergo tests like Electrocardiogram, Echocardiography and Coronary angiography.

  1. The Electrocardiogram (ECG) give information about the rhythm of the heart, any electrical disturbance of the heart and also if the blood supply is less.
  2. The Echocardiography is the sonography of the heart wherein its imaged and the pumping of the heart is studied. It’s the most important test to diagnose heart failure. It gives the physician information on heart pumping, the function of the valves and leaks across the valves. The pumping of the heart can be quantified as Ejection Fraction (EF) which is normally in the range of 55-65%. Any decrease in EF below the normal range suggests some weakness of the heart muscle and needs to be investigated further. Patients with EF lower that 35% entail more risk of sudden death and heart failure hospitalizations and need more specialized treatment.
  3. Coronary angiography: is necessary to diagnose blockages in the coronary arteries which would need subsequent correction by either angioplasty or bypass surgery.

 

Risks of Heart Failure:

Patients with HF are at high risk of Sudden Cardiac Death and recurrent hospitalizations due to heart failure episodes. The patients at most risk are the ones with an EF of less than or equal of 35%. HF patients keep getting admitted in hospitals due to recurrent dyspnea which need to be treated with intravenous medications.

 

Devices in Heart Failure:

There are 2 devices which can be used in HF treatments (1) Cardiac Resynchronization Therapy and (2) Implantable Cardiac Defibrillator

 

 

Summary:

Patients with heart failure are at risk of dying from progressive heart failure and sudden cardiac arrest. This can be now corrected and treated effectively by implanting devices (namely CRT and ICD respectively). However, these patients need to be carefully evaluated and selected by the cardiologist before undergoing these procedures so as to ensure maximum benefit.