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.

 

 

Devices for Heart Failure

Devices for Heart Failure:

 

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

 

(I) Cardiac Resynchronization Therapy:

The heart is made of 2 upper chambers called atria and 2 lower chambers called ventricles. An electrical system controls the synchronized pumping action of these chambers. The atria contract first followed by the 2 ventricles. The 2 ventricles contracts simultaneously to as to ensure optimal pumping of blood to the body and lungs. However this synchronized contraction (Synchrony) is lost between the atria and the ventricles and also between the 2 ventricles. This dys-synchrony leads to further less effective contraction of the heart thereby reducing thereby aggravating the heart failure. This Dys-synchrony can be easily diagnosed by the Physician with the help of the electrocardiogram and the echocardiogram.
CRT is designed to correct this dys-synchrony between the upper and lower chambers of the heart and also between the 2 lower chambers. This ensures simultaneous contraction of the 2 lower chambers thereby improving the contractions. In this procedure, a pacemaker (the size of a pager) is implanted just below the skin in the upper chest region and 3 wires (leads) are inserted into the heart to deliver electrical therapy. The 3 leads are positioned in the right upper, right lower chambers and the left lower chambers. The CRT device simultaneously stimulates the left and right ventricles and restores a coordinated, or “synchronous,” squeezing pattern. This reduces the electrical delay and results in a more coordinated and effective heart beat.

Who needs the CRT?
According to the Heart Rhythm Society, the ideal candidate for a CRT device is someone with:

  1. Moderate to severe heart failure symptoms, despite lifestyle changes and medication
  2. A weakened and enlarged heart muscle
  3. A significant electrical delay in the lower pumping chambers.

How effective is CRT?

There have been around 8-9 clinical trials involving around 5000 patients. Clinical studies demonstrate modest improvements in exercise tolerance, heart failure severity, and quality of life in most patients. Almost two-third of the patients implanted with the device benefit in their symptomatic status and also have decrease in the number of hospitalizations over the next few years. Improvement may happen quickly, but sometimes it can take several months.

(II). Implantable Cardiac Defibrillators (ICD)

ICD is a device designed to shock the heart out of a dangerous life threatening rhythm. The device is similar to the pacemaker and is the size of a pager. It is implanted below the skin in the upper chest and is then connected to a wire (lead) which monitors the heart rhythm 24 hours. Whenever it detects a dangerous heart rhythm, it delivers an internal shock to the heart and restores the normal rhythm.

Who needs ICD? Who is at risk of developing dangerous heart rhythm?

Dangerous heart rhythms can cause Sudden Cardiac Arrest which can cause instant death. Patients most at risk are those with compromised heart function (Ejection fraction < 35%). These patients if symptomatic need to undergo an ICD implantation so as to reduce their risk of dying from sudden cardiac arrests.

How effective is ICD?

There have been around 6 clinical trials involving around 3000 patients. Clinical studies demonstrate modest reduction in the death rates due to sudden cardiac arrest and have been life-saving in the majority of the patients.

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.

Pacemaker Implantation (PPM)

Pacemaker implantation is a procedure to put a small, battery-operated device called a pacemaker under the skin of your chest, just below your collarbone (clavicle), to help your heart beat regularly. Usually this is a minor surgical procedure performed under a local anaesthetic. Occasionally, the pacemaker may be implanted under general anaesthetic.

About a Pacemaker

The pacemaker is a small metal box weighing 20-40g, which contains a pulse generator (usually a lithium battery) attached to one or more wires/ leads that run to your heart. The pacemaker also contains a computer circuit that converts energy from the batteries into electrical impulses, which flow down the wires and stimulate your heart to contract.

Why do I need a pacemaker?

When you’re resting, your heart normally beats (or contracts) 50 to 80 times a minute. If you exert yourself or feel anxious or stressed your heart can beat at two or three times this rate to pump blood faster around your body. This beating of the heart is a result of generation of electrical current in the SA node which is situated in the right upper chamber of the heart. This current then get transmitted through a special tissue called AV node and His-Purkinje system to the lower chambers. Once the current reaches the lower chambers, they pump blood to the whole body. Any problem with either the generation or conduction of electrical impulses of the heart gives rise to Slow Heart Rates (Bradycardia). This can give rise to giddiness, lightheadedness, fatigue, breathlessness or episodes of fainting. The pacemaker is implanted to correct this problem.

What will be done once I get admitted?

You will be told to get admitted one day prior or early morning on the day of the procedure. Once you finish the admission procedure on the ground floor of the Main Hospital building, you will be allotted a bed on one of the floor or in the ICU in the Main Hospital building. You will be examined by one of the nurses and the doctors to see if you have any problems and your medications and reports checked. We are here to make you comfortable and relaxed before the procedure. If you have any doubts or queries do feel free to ask your nurse or doctor. You have nothing to lose by asking queries.

What preparation do I need before the pacemaker implantation?

Your doctor will tell you about the procedure in advance. He will explain to you the procedure in detail before getting admitted and after getting admitted. Your doctor will tell you ahead of time whether to stop taking any of your medications.

Few things necessary before the procedure:

  1. An informed written consent will be taken from you explaining the procedure, its details and its risks if any.
  2. You will be told not to eat or drink at least 6 hours before the start of the procedure
  1. The left or right side of your chest will be cleaned and shaved.
  1. An intravenous IV cannula will be inserted in one of you hands/arms before the start of the procedure to give you fluids and medications.
  2. An intravenous antibiotic will be given intravenously before the start of the procedure
  3. Please let the doctor know if you have any allergies or reactions to any drugs.

Where are these procedures performed?

The procedure is performed on the second floor in the Cath lab situated in the Main Building. The Cath lab laboratory has a moveable procedure table on which the patient lies down and an X-ray machine that is suspended over the table. This X-ray machine guides the doctor in placing the wires or leads within your heart. In addition, there are monitors which will monitor your heart rate and blood pressure.

Before the Start of the procedure:

  • You will lie flat on the procedure table. The electrocardiogram (ECG) leads will be connected on your body to record your ECG during the procedure. The nurses will thoroughly cleanse the chest and neck region with special soap. The procedure is done under local anesthesia with intravenous sedation. You will be given intravenous drugs to make you feel sleepy and relaxed. This will relieve
  • Sterile drapes will be used to cover you from your neck to your feet.
  • A support will be placed below your waist and arms to prevent your hands from coming in contact with the sterile area.

What kind of anaesthetic will I have?
The procedure is done under local anaesthetic with intravenous sedation. A medication will be given through your IV line to relax you and make you feel drowsy, but you won’t be asleep during the procedure.

Pacemaker Implantation
After you have been adequately sedated and relaxed, the doctor will inject local anesthesia at the site of pacemaker implantation (upper part of chest just below your collar bone. Once the effect of the anesthesia has taken place, the cardiologist makes a small incision of 5-6 cm (2-3 inches) below the collarbone and makes a small ‘pocket’ to insert your pacemaker. He then inserts the pacing lead into a vein. He then guides this into the correct chamber of your heart using X-ray guidance. The pacing lead is connected to the pacemaker and the pacemaker is fitted into a small ‘pocket’ under the skin of your upper chest. The cardiologist then tests how much electrical energy is needed to stimulate your heartbeat and adjusts the pacemaker accordingly. Some patients may need 2 leads to be implanted which will be told to you before the procedure. The procedure usually takes between 60 and 120 minutes or longer if you’re having a bi-ventricular pacemaker or other heart surgery at the same time. You’ll usually need an overnight stay in hospital and a day’s rest after the procedure. After the pacemaker has been implanted, the doctor uses an external device (programmer) to program the final settings based on your response to the procedure.

Will I feel anything?
You’ll feel an initial burning or pricking sensation when the cardiologist injects the local anaesthetic. You’ll soon become numb, but you may feel a pulling sensation as the cardiologist makes the pocket in the tissue under your skin for the pacemaker. When the leads are being tested, you may feel your heart rate increase or your heart beat faster. Please tell the team what symptoms you’re feeling. You should not feel pain. If you do, it’s important to tell the team immediately.

Risks of pacemaker implantation

  • Infection: There is a small risk of infection (about 1%) at the site of the implant. If it spreads, there’s a risk the pacemaker may need to be replaced.
  • Loosening of pacing leads: There’s a small risk that one of the leads might move out of position (about 1%) which is why you’re advised to avoid vigorous exercise for a few weeks.
  • Air trapped in the chest (pneumothorax): There’s a small risk of air leaking from the lungs to the chest during the procedure. The doctor will check this on your chest X-rays before you leave hospital.
  • Death: This is very rare with pacemaker implantation
  • The operation can’t be performed: For about one in 100 people the operation is too difficult and the doctor has to stop without fitting the pacemaker on the first occasion.

Post procedure care

After the procedure the patient will be shifted to the ICU for monitoring of the heart rhythm. You should avoid vigorous movement of the arm where the pacemaker is implanted. An X-ray of your chest and ECG will be done on the same day after the procedure. After some rest, the patient can begin moving about, and generally is ready to go home the next day after the pacemaker has been checked.

Will I feel pain after the procedure? 
You may feel some pain or discomfort during the first 48 hours and will be given pain relieving medication

Before Discharge

Before you go home the cardiologist will come to see you and discuss the results of the procedure and answer any questions you have.  After your pacemaker has been fitted, you’ll be given a pacemaker registration card which contains details of the make and model of your pacemaker. You should always carry this with you in case of an emergency. You may also be given extra information produced by the pacemaker manufacturer.

Wound care 
You should avoid getting the wound wet for 7 days after the procedure. Please keep the wound dry and clean. If you notice any serious swelling, pain or redness, please consult your doctor. Nowadays, the cardiologist uses absorbable sutures, so there is no need to get the sutures removed after 7 days. Your first follow up visit to the hospital will be after 7 days.

How soon can I drive? 
If you are driving your personal vehicle, you can start driving again after a week (provided you don’t have any symptoms, such as dizziness or fainting, which would affect your driving). If you are driving a large or passenger-carrying vehicle (public), you’ll have to wait for six weeks after your pacemaker is fitted.

When can I do exercise or play sports again? 
You should avoid strenuous activities for around three or four weeks after having your pacemaker fitted, after which you should be able to do most activities and sports. If you play contact sports, however, such as football or rugby, it’s important to avoid collisions. You may want to wear a protective pad. You should also avoid extreme activities, e.g. squash/ tennis, although swimming should be ok.