Ischaemic and Valvular Heart Disease

• Symptoms of heart disease:

  • Chest pain - usually due to ischaemic heart disease - could also be due to pericarditis (inflammation of outside of the heart), but that's much rarer
  • Breathlessness - usually due to heart failure
  • Ankle swelling - sign of heart failure due to oedema
  • Palpitations (awareness of the heartbeat) - arrhythmia
  • Faintness - indicates low blood pressure, can be caused by arrhythmia which leads to low blood pressure
• Signs of heart disease in clothed pt:

  • General appearance - breathlessness, pallor, sweating, cyanosis (blue tinges around mouth, lips and tongue in particular)
  • Pulse - rate, rhythm, volume (full volume = easy to feel - poor volume = weak, hard to feel)
  • Blood pressure
  • Jugular Venous Pressure (JVP) - raised in heart failure - jugular vein in neck above collar bone
  • Peripheral oedema - 'pitting' indents on pressure
• Signs of heart disease in clothed pt - peripheral oedema - 'pitting' indents on pressure:

  • When the veins are congested, the pressure goes backwards to the capillaries, fluid leaks out of them into the interstitial tissues and drains downwards by gravity, resulting in oedema, particularly in the ankles
  • Swellings of fluid under the skin - if you apply pressure for around 15 seconds then take the pressure away, a pit should be left behind
• Other signs of heart disease:

  • Heart sounds
  • Normal sounds are closure of mitral and aortic valves
  • Additional sounds = murmurs - due to turbulent flow through abnormal valve (regurgitation)
  • Lung sounds
  • Normal 'vesicular' breath sounds
  • Additional sounds - inspiratory crackles at bases indicate pulmonary oedema
  • Reduced breath sounds with dullness to percussion indicates pleural effusion
• Ischaemic heart disease:

  • Synonym: coronary heart disease
  • Refers to heart disease caused by coronary artery narrowing and blockage
  • Underlying pathological processes are atherosclerosis (narrowing) and thrombosis (blockage)
  • Consequences = angina (narrowing of coronary artery) and myocardial infarction (blockage of coronary artery due to thrombosis leading to death of heart tissue)
• Chest pain in ischaemic heart disease (IHD) - angina:

  • Site: central chest
  • Radiation: left arm, both arms, neck, jaw, back, upper abdomen
  • Nature: heavy, tight, gripping
  • Severity: moderate
  • Associated features: breathless
  • Length: few minutes
  • Precipitants: exercise, emotion, cold, food
  • Relieving factors: rest, GTN spray (glyceryl trinitrate)
• Chest pain in ischaemic heart disease (IHD) - acute coronary syndrome (unstable angina, MI):

  • Site: central chest
  • Radiation: left arm, both arms, neck, jaw, back, upper abdomen
  • Nature: heavy, tight, gripping
  • Severity: severe
  • Associated features: sweating, nausea, breathless
  • Length: 20 mins+
  • Precipitants: usually none
  • Relieving factors: GTN spray (glyceryl trinitrate) ineffective
• GTN spray (glyceryl trinitrate) dilates veins to reduce strain on heart and speed up resolution of angina.
• Management of angina:

  • Stop and rest
  • GTN spray to shorten attack
  • Anti-anginal drugs to be taken regularly to reduce the frequency/severity of angina
  • Percutaneous coronary intervention - balloon stretches coronary artery and stent is placed to hold it open
  • Coronary artery bypass graft - vein taken from leg and sewn across the narrowing - or another artery from the chest is taken to bypass the narrowing
• Management of angina:

  • Anti-anginal drugs to be taken regularly to reduce the frequency/severity of angina:
  • Beta-blockers  e.g. Bisoprolol - can also be used to slow the heart down/treat hypertension
  • Nitrates e.g. Isosorbide mononitrate - nitrates only really ever used for angina, not other heart conditions
  • Calcium channel blockers e.g. Amlodipine - can be used for hypertension as well as angina
  • Others - nicorandil, ivabradine (slows heart down), ranolazine (changes mechanisms of heart muscle cells)
• Someone with angina is at higher risk of having a myocardial infarction.
• Prevention of myocardial infarction:

  • Primary prevention is in pts without any disease
  • Secondary prevention is in pts with evidence of disease, eg:
  • Angina
  • Previous myocardial infarctions
  • Other vascular disease, such as stroke or claudication (narrowing of arteries in legs)
• Treatable risk factors for myocardial infarctions:

  • Smoking
  • Hyperlipidaemia
  • Hypertension
  • Diabetes/overweight
  • Increase clotting (rare cause of angina but can cause MI)
  • Lifestyle - poor diet, lack of exercise
• Risk markers for myocardial infarctions:

  • Age
  • Male sex
  • Racial group - (south asians at higher risk)
  • Post-menopausal women
• Primary prevention strategies for MI:

  • Lifestyle advice - lose weight, reduce fat and salt intake, stop smoking
  • Treat hypertension
  • Treat hyperlipidaemia
  • Sometimes anti-platelet drugs, for high risk groups
• Secondary prevention strategies for MI:

  • ACE (angiotensin-converting enzyme) inhibitors and beta blockers post MI
  • Coronary intervention - stenting/bypass
  • Antithrombotic therapy - mainly antiplatelet drugs
  • Dual antiplatelet for high risk groups e.g. recent event or stent
• Cardiac investigations:

  • ECG - show changes during angina or MI, and heart rhythm
  • Chest x-ray - heart enlargement and pulmonary oedema (fluid on the lungs)
  • Echocardiogram (ultrasound with doppler flow study) - shows structure and movement of valves and heart muscle, and flow across valves
  • Stress tests e.g. stress echo, myocardial perfusion scan - for reversible ischaemia
  • Myocardial perfusion scan = radio-labelled dye is injected into bloodstream, goes through heart and shows where the blood is flowing and where it's not
• Cardiac investigations:

  • CT coronary angiogram/calcium scoring - for risk stratification
  • Cardiac MRI - specialist investigation
  • Coronary angiogram - invasive test to guide intervention such as stent
  • Catheter is threaded along the arteries from the arm or leg and up into the heart - x-ray dye injected down coronary arteries to give good pictures of coronary artery anatomy and allow access to do an angioplasty with a balloon and to place a stent
• Cardiac investigations:

  • Troponin levels - blood test to detect release of cardiac muscle proteins in acute coronary syndrome
  • When heart muscle is damaged by a heart attack, the heart muscle cells leak some of their proteins out into the blood
  • Troponin = heart muscle protein
  • Therefore troponin levels increasing = sign that someone's having a heart attack or has had one
• Management of myocardial infarction:

  • Medical emergency - paramedics perform ECG and triage to specialist centre
  • For ST-elevation MI (STEMI) - immediate coronary intervention and stent plus medical treatment
  • For non-ST-elevation MI (NSTEMI) - antithrombotics, beta blockers, nitrates. Risk stratification and intervention in high risk
• Acute complications of MI:

  • Arrhythmias including cardiac arrest
  • Heart failure
  • Cardiogenic shock (severe heart failure - so bad it fails to pump blood forwards, so whole body goes into shock and organ failure ensues due to poor perfusion of the tissues)
  • Rupture of valve, septum
  • Aneurysm (stretching/ballooning) of left ventricle
• Chronic complications of MI:

  • Chronic heart failure
  • Recurrent arrhythmias/risk of arrest
  • Angina
  • Further MI
• 4 valves in the heart:

  • Mitral (left atrium to left ventricle)
  • Aortic (left ventricle to aorta)
  • Tricuspid (right atrium to right ventricle)
  • Pulmonary (right ventricle to pulmonary artery)
• 2 problems with the heart valves:

  • Narrowing - stenosis
  • Leaking - regurgitation (old synonym - incompetence) - failure to close properly
• Common valve problems:

  • Aortic stenosis (AS) - narrowing of the aortic valve - common with age - atherosclerosis can cause this
  • Mitral regurgitation (MR) - various causes including ischaemic heart disease
  • Tricupsid regurgitation (TR) - can be due to heart failure or chronic lung disease causing pulmonary hypertension (high blood pressure in the lungs) - puts pressure on the right ventricle, causing right ventricle to fail and tricuspid valve to regurgitate
  • Mitral stenosis (MS) - still common in developing countries, usually caused by rheumatic fever
• Symptoms of valvular heart disease:

  • Heart failure - breathlessness, fatigue and oedema
  • Palpitations either on exercise or with arrhythmia
  • Faintness due to low blood pressure upon exertion, especially in AS (aortic stenosis) because enough blood can't get through aortic valve
  • Chest pain rarely due to valvular disease, more commonly due to ischaemic heart disease, can occur in AS (aortic stenosis) though
• Signs of valvular heart disease:

  • Pulse - altered volume - increased in AR (aortic regurgitation), slow rising in AS (aortic stenosis)
  • Pulse - irregular in arrhythmias
  • Blood pressure low in AS (aortic stenosis), but high in AR (aortic regurgitation)
  • Signs of endocarditis (rare but important) - splinter haemorrhages in nails, clubbing, fever
  • Infective endocarditis = an infection which goes on to abnormal heart valves - thought to arise from oral flora which end up on the heart valves
• Treatments for valvular heart disease:

  • Treat symptoms of arrhythmia or heart failure - e.g. anti-arrhythmics, diuretics for heart failure
  • Surgical valve repair or replacement:
  • Tissue valve - limited lifespan (only around 10 years)
  • Mechanical valve - more durable but needs anticoagulation (because the metal/plastic valve can get blood clots forming on it)
  • Minimally invasive procedures eg mitral valve clip for regurgitation or transcatheter aortic valve intervention (TAVI) for AS (aortic stenosis)
• Sign of heart disease = arcus senilis - white ring between white part of eye and iris - due to cholesterol deposition - normal in all people as they get older. When it occurs in young people though, it can be a sign of hyperlipidaemia.

  
• White line at bottom of iris = premature arcus senilis. Pt here has familial hypercholesterolaemia.

  
• Familial hypercholesterolaemia also causes cholesterol deposition in the tendons - rare but still a sign. Discreet lipid deposits can also be present in the tendons on the back of the hands - another sign of hyperlipidaemia.

  
• Example of pitting oedema  pressed on the swelling for around 15 seconds, when released pit left behind - sign of heart failure.

  
• Pts with pitting oedema also tend to have a raised jugular venous pressure. Raised vein above clavicle, below ear lobe. Raised vein can be seen when patient is at rest.

  
• Finger clubbing can occur in non-cardiac diseases, particularly lung disease. Curvature of the nails with a spongy feeling where the nail joins to the skin. Can be a sign of congenital heart disease but especially endocarditis - takes a while to develop so must have had a low grade infection for weeks and months before it develops.

  
• Splinter haemorrhage - if it's just one or two at the end of the nail then it could have been trauma related... but if there are several ones like this partway down the nail then it's a characteristic feature of bacterial endocarditis.

  
• Pt with a raised jugular venous pressure. Below clavicle on RHS is a pacemaker - large watch shape - wires go from it into the subclavian vein underneath the clavicle - has caused thrombosis of the subclavian vein where the wires go in - veins dilated over the pacemaker - therefore the patient's raised jugular venous pressure is because of a thrombosis in the vein rather than because of heart failure.