MYOCARDIAL INFARCTION, FIBRINOLYSIS, ANTIFIBRINOLYTIC DRUGS AND HAEMOSTATICS

MYOCARDIAL INFACTION

Most heart attacks are caused by a blood clot that blocks one of the coronary arteries. The coronary arteries bring blood and oxygen to the heart. If the blood flow is blocked, the heart is starved of oxygen and heart cells die.

The medical term for this is myocardial infarction.

Causes

A substance called plaque can build up in the walls of your coronary arteries. This plaque is made up of cholesterol and other cells.

A heart attack may occur when:

-A tear in the plaque occurs. This triggers blood platelets and other substances to form a blood a clot at the site that blocks blood from flowing to the heart. This is the most common cause of heart attack.

-A slow buildup of plaque may narrow one of the coronary arteries so that it is almost blocked.

The cause of heart attack is not always known.

Heart attack may occur:

-when you are resting or asleep

-after a sudden increase in physical activity

-when you are active outside in cold weather

-after sudden, severe emotional or physical stress, including an illness.

Symptoms

Chest pain is the most common symptom of a heart attack.

You may feel the pain in only one part of your body OR pain may move from your chest to your arms, shoulder, neck, teeth, jaw, belly area, or back.

The pain can be severe or mild. It can feel like:

-a tight band around the chest

-bad indigestion

-something heavy sitting on your chest

-squeezing or heavy pressure.

The pain most often lasts longer than 20 minutes. Rest and a medicine to relax the blood vessels (called nitroglycerin) may not completely relieve the pain of a heart attack. Symptoms may also go away and come back.

Other symptoms of a heart attack can include: anxiety, cough, fainting, light-headedness, dizziness, nause or vomiting, palpitations, shortness of breath ans sweating.

Some people (the elderly, people with diabetes, and women) may have little or no chest pain. Or, they may have unusual symptoms such as shortness of breath, fatigue, and weakness. A "silent heart attack" is a heart attack with no symptoms.

FIBRINOLYTIC DRUGS
Fibrinolytic drugs act as thrombolytics by activating plasminogento form plasmin, which degrades fibrin and so breaks up thrombi.
-Alteplase (Actilyse).
-Reteplase (Rapilysin).
-Streptokinase (Streptase).
-Tenecteplase (Metalyse).
-Urokinase.

ANTIFIBRINOLYTIC DRUGS AND HAEMOSTATICS
-Etamsylate: blood loss in menorrhagia (Dicynene).
-Tranexamic acid: it can be used to prevent bleeding or to treat bleeding associated withexcessive fibrinolysis (Cyklokapron).

Blood products:
-Antithrombin III concentrate: indicated for congenital deficiency of antithrombin III.
-Dried prothrombin complex.
-Drotrecogin alfa (activated).
-Factor VIIa (recombinant).
-Factor VIII fraction, dried.
-Factor VIII inhibitor bypassing fraction.
-Factor IX fraction, dried.
-Factor XIII fraction, dried.
-Fresh frozen plasma.
-Protein C concentrate.

Source:
-http://www.nlm.nih.gov/medlineplus/ency/article/000195.htm
-BNF 57 March 2009

SYMPATHOMIMETICS, ANTICOAGULANTS, PROTAMINE AND ANTIPLATELET DRUGS.

SYMPATHOMIMETICS

They act increasing both heart rate and contractility, it can cause peripheral vasodilation or vasoconstriction.

1. Inotropic sympathomimetics: 

-Dobutamine (Indications: inotropic support in infarction, cardiac surgery, cardiomyopathies, septic shock and cardiogenic shock).

-Dopamine Hydrochloride (Indications: cardiogenic shock in infarction or cardiac surgery).

-Dopexamine Hydrochloride (Indications: inotropic support and vasodilator in exacerbations of chronic heart failure and in heart failure associated with cardiac surgery).

2. Vasoconstrictor sympathomimetics (raise blood pressure transiently):

-Ephedrine Hydrochloride.

-Metaraminol.

-Noradrenaline Acid Tartrate/ Norepinephrine Bitartrate.

-Phenylephrine Hydrochloride.

3. Cardiopulmonary resuscitation:

-Adrenaline/Epinephrine.

ANTICOAGULANTS AND PROTAMINE

Mainly used to prevent thrombus formation or extension of an existing thrombus in the slower-moving venous side of the circulation, prevention and treatment of deep-vein thrombosis in the legs. They are used to prevent thrombi forming on prosthetic heart valves.

1. Parenteral anticoagulants:

-Heparin.

-Bemiparin Sodium (Zibor).

-Dalteparin Sodium (Fragmin).

-Enoxaparin Sodium (Clexane).

-Tinzaparin Sodium (Innohep).

-Danaparoid Sodium (Orgaran).

-Bivalirudin (Angiox).

-Lepirudin (Refludan).

-Epoprostenol (Flolan).

-Fondaparinux Sodium (Arixtra).

2. Oral anticoagulants:

-Warfarin Sodium.

-Acenocoumarol (Sinthrome).

-Phenindione.

-Dabigatran Etexilate (Pradaxa).

-Rivaroxaban (Xarelto).

3. Protamine sulphate (Prosulf).

ANTIPLATELET DRUGS

-Abciximab.

-Aspirin (Angettes 75, Caprin).

-Clopidogrel (Plavix).

-Dipyridamole (Persantin).

-Eptifibatide (Integrilín).

-Tirofiban (Aggrastal)

Sources:

-http://www.evidence.nhs.uk

-BNF 57 March 2009

ANGINA

ANGINA

Angina is chest pain or discomfort you feel when there is not enough blood flow to your heart muscle. Your heart muscle needs the oxygen that the blood carries. Angina may feel like pressure or a squeezing pain in your chest. It may feel like indigestion. You may also feel pain in your shoulders, arms, neck, jaw, or back.

Angina is a symptom of coronary artery disease(CAD), the most common heart disease. CAD happens when a sticky substance called plaque builds up in the arteries that supply blood to the heart, reducing blood flow.

There are three types of angina:

-Stable angina is the most common type. It happens when the heart is working harder than usual. Stable angina has a regular pattern. Rest and medicines usually help.

-Unstable angina is the most dangerous. It does not follow a pattern and can happen without physical exertion. It does not go away with rest or medicine. It is a sign that you could have a heart attack soon.

-Variant angina is rare. It happens when you are resting. Medicines can help.

Nitrates, calcium-channel blockers and other antianginal drugs.
1. Nitrates:
-Glyceryl Trinitrate (GTN, Coro-Nitro Pump Spray, Glytrin Spray, Nitromin, Suscard, Nitrocine, Nitronal, Deponit, Minitran, Percutol, Nitro-Dur, Transiderm-Nitro, Trintek).
-Isosorbide Dinitrate (Angitak, Cedocard Retard, Isoket Retard).
-Isosorbide Mononitrate (Elantan, Ismo, Chemydur, Imdur, Isodur, Isotard. Isib, Modisal, Monomax, Monomil, Monosorb, Zemon).
2. Calcium-channel blockers:
-Amlodipine (Istin, Exforge).
-Diltiazem Hydrochloride (Tildiem, Adizem, Angitil, Calcicard, Dilcardia, Dilzem, Slozem, Tildiem, Viazem, Zemtard).
-Felodipine (Plendil).
-Isradipine (Prescal).
-Lacidipine (Motens).
-Lercanidipine Hydrochloride (Zanidip).
-Nicardipine Hydrochloride (Cardene).
-Nifedipine (Adalat, Adipine, Coracten, Fortipine, Hypolar Retard, Nifedipress, Tensipine, Vaini).
-Nimodipine (Nimotop).
-Verapamil Hydrochloride (Cordilox, Securon, Univer, Verapress, Vertab).
3. Other antianginal drugs:
-Ivabradine (Procoralan).
-Nicorandil (Ikorel).
4. Peripheral vasodilators and related drugs:
-Cilostazol (Pletal).
-Inositol Nicotinate (Hexopal).
-Moxisylyte (Opilon).
-Naftidrofuryl Oxalate (Praxilene).
-Pentoxifylline (Trental).

Sources:
-http://www.nlm.nih.gov/bsd/pmresources.html
-BNF 57 March 2009

HYPERTENSION AND HEART FAILURE

Hypertension

Blood pressure is a measurement of the force against the walls of your arteries as your heart pumps blood through your body. Hypertension is another term used to describe high blood pressure.

Blood pressure readings are given as two numbers. The top number is called the systolic blood pressure. The bottom number is called the diastolic blood pressure. For example, 120 over 80 (written as 120/80 mmHg).

One or both of these numbers can be too high.

-Normal blood pressure is when your blood pressure is lower than 120/80 mmHg most of the time.

-High blood pressure (hypertension) is when your blood pressure is 140/90 mmHg or above most of the time.

-If your blood pressure numbers are 120/80 or higher, but below 140/90, it is called pre-hypertension.

If you have heart or kidney problems, or you had a stroke, your doctor may want your blood pressure to be even lower than that of people who do not have these conditions.

Causes

Many factors can affect blood pressure, including:

-The amount of water and salt you have in your body

T-he condition of your kidneys, nervous system, or blood vessels

-Your hormone levels

You are more likely to be told your blood pressure is too high as you get older. This is because your blood vessels become stiffer as you age. When that happens, your blood pressure goes up. High blood pressure increases your chance of having a stroke, heart attack, heart failure, kidney disease, or early death.

You have a higher risk of high blood pressure if:

-You are African American

-You are obese

-You are often stressed or anxious

-You drink too much alcohol (more than 1 drink per day for women and more than 2 drinks per day for men)

-You eat too much salt

-You have a family history of high blood pressure

-You have diabetes

-You smoke.

Most of the time, no cause of high blood pressure is found. This is called essential hypertension.

High blood pressure that is caused by another medical condition or medicine you are taking is called secondary hypertension. Secondary hypertension may be due to:

-Chronic kidney disease

-Disorders of the adrenal gland

-Hyperparathyroidism

-Pregnancy or preeclamsia 

-Medications such as birth control pills, diet pills, some cold medicines, and migraine medicines

-Narrowed artery that supplies blood to the kidney (renal artery stenosis).

Symptoms

Most of the time, there are no symptoms. For most patients, high blood pressure is found when they visit their doctors or have it checked elsewhere.

Because there are no symptoms, people can develop heart disease and kidney problems without knowing they have high blood pressure.

Malignant hypertension is a dangerous form of very high blood pressure. Symptoms include:

-Severe headache

-Nausea or vomiting

-Confusion

-Vision changes

-Nosebleed.

Heart failure

Heart failure is a complex syndrome characterised by reduced heart efficiency and resultant haemodynamic and neurohormal responses (Poole-Wilson 1985).

Heart failure is caused by a number of pathological conditions. Some causes are reversible, but others are not.

Causes of heart failure:

-Ischaemic heart disease.

-Hypertension.

-Arrythmias.

-Valve disorders.

-Myocarditis.

-Alcohol-induced cardiomyopathy (heart muscle abnormalities).

-Chemotherapy-induced cardiomyopathy.

-Genetic cardiomyopathies.

-Amyloidosis.

-Sarcoidosis.

-Metabolic disorders.

(*This is a shortened list).

Patients can have acute heart failure without underlying chronic heart failure but more commonly acute presentations are due to destabilisation of chronic disease.

Patients who are well managed can have a good quality of life and extend their prognosis, but heart failure is unpredictable and difficult to prognosticate for individual patients.

Diagnosis

Heart failure should be diagnosed using the pathway in the European Society of Cardiology (ESC) guidelines (McMurray et al 2012).

Once diagnosis is confirmed the severity of the symptoms can be expressed using the New York Heart Association (NYHA) classification.

DRUGS USED IN HYPERTENSION AND HEART FAILURE

Angiotensin-converting enzyme inhibitors:

1. Vasodilator antihypertensive drugs:

-Ambrisentan (Volibris).

-Bosentan (Tracleer).

-Diazoxide (Eudemine).

-Hydralazine Hydrochloride (Apresoline).

-Iloprost (Ventavis).

-Minoxidil (Loniten).

-Sildenafil (Revatio, Viagra).

-Sitaxentan sodium (Thelin).

-Sodium Nitroprusside.

2. Centrally acting antihypertensive drugs:

-Clonindine Hydrochloride (Catapres, Dixarit).

-Methyldopa (Aldomet).

-Moxonidine (Physiotens).

3. Adrenergic neurone blocking drugs:

-Guanethidine Monosulphate (Ismelin).

4. Alpha-adrenoceptor blocking drugs:

-Doxazosin (Cardura).

-Indoramin (Baratol, Doralese).

-Prazosin (Hypovase).

-Terazosin (Hytrin).

-Phenoxybenzamine Hydrochloride (Dibenyline).

-Phentolamine Mesilate (Rogitine).

5. Drugs affecting the renin-angiotensin system:
The main indications of ACE inhibitors are heart failure and hypertension among others.
-Captopril (Capoten).
-Cilazapril (Vascace).
-Enalapril Maleate (Innovace).
-Fosinopril Sodium (Staril).
-Imidapril Hydrochloride (Tanatril).
-Lisinopril (Carace, Zestril).
-Moexipril Hydrochloride (Perdix).
-Perindopril Erbumine.
-Quinapril.
-Ramipril.
-Trandolapril.

Angiotensin-II receptor antagonists
-Candesartan Cilexetil (Amias).
-Eprosartan (Teveten).
-Irbesartan (Aprovel).
-Losartan Potassium (Cozaar).
-Olmesartan Medoxomil (Olmetec).
-Telmisartan (Micardis).
-Valsartan (Diovan).

Renin inhibitors
-Aliskiren (Rasilez).


Sources:
-http://www.nlm.nih.gov/medlineplus/
-BNF 57 March 2009
-nop.rcnpublishing.com/ September 2014/ Volume 26/ Number 7.

ANTI-ARRHYTMIC DRUGS AND BETA-ADRENOCEPTOR BLOCKING DRUGS

ARRHYTHMIAS

An arrhythmia is a disorder of the heart rate (pulse) or heart rhythm. The heart can beat too fast (tachycardia), too slow (bradycardia), or irregularly.

Causes

Arrhythmias are caused by problems with the heart's electrical conduction system:

-Abnormal (extra) signals may occur.

-Electrical signals may be blocked or slowed.

-Electrical signals travel in new or different pathways through the heart.

Some common causes of abnormal heartbeats are:

-Abnormal levels of potassium or other substances in the body

-Heart attack, or a damaged heart muscle from a past heart attack

-Heart disease that is present at birth (congenital)

-Heart failure or an enlarged heart

-Overactive thyroid gland

Arrhythmias may also be caused by some substances or drugs, including: alcohol, caffeine, or stimulant drugs, heart or blood pressure medicines, cigarette smoking (nicotine), drugs that mimic the activity of your nervous system and medicines used for depression or psychosis.

Sometimes medicines used to treat one type of arrhythmia will cause another type of abnormal heart rhythm.

Some of the more common abnormal heart rhythms are:

-Tachycardia: supraventricular tachycardia (SVT) or ventricular tachycardia (ventricular fibrillation).

-Bradycardia: sinus node dysfunction or heart block.

Other classification:                                                                                                                           Arrhythmias originating in the Atria:

-Atrial fibrillation.

-Atrial flutter.

-Supraventricular tachycardias (PSVT).

-Wolff-Parkinson-White syndrome.

-Premature supraventricular contraction or premature atrial contraction (PAC).

-Sick sinus syndrome.

-Sinus arrhythmia.

-Sinus tachycardia.

-Multifocal atrial tachycardia.

 Arrhythmias originating in the Ventricles:

-Premature ventricular contraction (PVC)

-Ventricular Fibrillation

-Ventricular tachycardia.

Symptoms

An arrhythmia may be present all of the time or it may come and go. You may or may not feel symptoms when the arrhythmia is present. Or, you may only notice symptoms when you are more active.

Symptoms can be very mild, or they may be severe or even life-threatening.

Common symptoms that may occur when the arrhythmia is present include: chest pain, fainting, light-headedness, dizziness, paleness, shortness of breath or sweating.

Treatment

When an arrhythmia is serious, you may need urgent treatment to restore a normal rhythm. This may include:

-Electrical "shock" therapy (defibrillation or cardioversion)

-Implanting a short-term heart pacemaker

-Medicines given through a vein (intravenous) or by mouth.

Sometimes, better treatment for your angina or heart failure will lower your chance of having an arrhythmia.

Medicines called anti-arrhythmic drugs may be used:

-To prevent an arrhythmia from happening again

-To keep your heart rate from becoming too fast or too slow

Other treatments to prevent or treat abnormal heart rhythms include: cardiac ablation, implantable cardiac defibrillator or a pacemaker.

ANTI-ARRHYTMIC DRUGS

-Adenosine: rapid reversion to sinus rhythm of paroxysmal supraventricular tachycardias. (Adenocor).

-Amiodarone hydrochloride: treatment of arrhythmias particularly when other drugs are ineffective or contraindicated. (Cordarone).

-Disopyramide: for ventricular or supraventricular arrhythmias. (Rythmodan). 

-Flecainide acetate (Tambocor).

-Propafenone hydrochloride: for ventricular arrhythmias and paroxysmal supraventricular tachyarrhythmias. (Arythmol).

-Lidocaine hydrochloride: for ventricular arrhythmias. (Minijet Lignocaine).

BETA-ADRENOCEPTOR BLOCKING DRUGS

Indicated for hypertension, angina, myocardial infarction, arrhythmias, heart failure and thyrotoxicosis among others.

-Propanolol hydrochloride (Inderal).

-Acebutolol (Sectral).

-Atenolol (Tenormin, with diuretic: Co-tenidone, Kalten, Tenoret 50 and Tenoretic, with calcium-channel blocker: Beta-adalat and Tenif).

-Bisoprolol fumarate (Cardicor, Emcor).

-Carvedilol (Eucardic).

-Celiprolol hydrochloride (Celectol).

-Esmolol hydrochloride (Brevibloc).

-Labetalol hydrochloride (Trandate).

-Metoprolol tartrate (Betaloc, Lopresor).

-Nadolol (Corgard).

-Nebivolol (Nebilet).

-Oxprenolol hydrochloride (Trasicor, with diuretic: Trasidex).

-Pindolol (Visken, with diuretic: Viskaldix).

-Sotalol hydrochloride (Beta-cardone, Sotacor).

-Timolol maleate (Betim, with diuretic: Prestim).

Sources:
-http://www.nlm.nih.gov/medlineplus/
-http://umm.edu/programs/heart/services/conditions/arrhythmias/types
-BNF 57 March 2009