Cardiac

Cards (28)

  • Elevated JVP suggests elevated central venous pressure and is most commonly associated with right heart failure. The back up of blood leads to an increase in venous blood pressure. When pressure is placed onto the liver, pushing blood into the right atrium, the inability of the heart to accommodate the increased volume it forces it up the superior vena cava and into the jugular veins.
  • Left-sided heart failure builds pressure into the pulmonary veins and eventually increases blood pressure in the right ventricle. As this pressure increases, the right ventricle has to work harder to accommodate it, leading to hypertrophy or dilation. This is known as cor pulmonale. Pressure will eventually build into systemic venous circulation. This may increase portal vein pressure leading to portal vein hypertension, which can lead to ascites, peripheral oedema and varices.
  • A collapsing pulse is typically indicative of aortic regurgitation, perhaps from aortic valve stenosis or prolapse, but can also indicate serious life threatening conditions like aortic dissection. Other potential indications are patent ductus arteriosus and anaemia.
  • Radial Pulse Mismatch typically indicates an arrhythmia, with the most common being atrial fibrilation. Ectopic Heartbeats are also common causes.
  • Valvular stenosis is the narrowing and stiffening of a valve in the heart, restricting blood flow. Aortic Stenosis leads to a harsh systolic murmur at right upper sternal border and radiating to the carotids. Mitral Stenosis is heard as a diastolic rumble with an opening snap, best heard at the apex with the patient lying on their left side.
    Valvular prolapse usually affects the mitral valve and occurs when the valve leaflets bugle back into the left atrium during systole. It produces a mid-systolic click followed by a late systolic murmur if regurgitation is present.
  • Atrial fibrilation can cause stasis of blood leading to the formation of a thrombus, which is in danger of embolising to the brain causing stroke.
    Atrial fibrilation can also worsen existing heart failure.
  • A bounding pulse can indicate aortic regurgitation, which leads to the left ventricle having to pump more forcefully with each beat leading to a high stroke volume. 
    It can also indicate an arteriovenous fistula (an abnormal connection between arteries and veins bypassing the capillary system); fever or sepsis (due to the bodies increased demand for oxygen); and hyperthyroidism (because the condition can increase heart rate and contractility.
  • Heaves are forceful cardiac motions felt by the flat of the hand, most commonly felt at the left sternal border. They indicate left ventricular hypertrophy.
  • Thrills are a palpable vibration on the chest wall similar to a cat purring. They indicate turbulent blood flow in the heart and are associated with valvular stenosis, regurgitation or septal defects.
  • Stroke Volume is the amount of blood pumped by the left ventricle in a single contraction with the normal range being 70-100 milliliters per beat. It is determined by pre-load, afterload and contractility.
  • Cardiac Output is the volume of blood the heart pumps per minute. It is calculated by multiplying stroke volume with heart rate.
  • Ejection Fraction is the proportion of blood pumped by the ventricles with each contraction, expressed as a percentage. It is calculated by dividing stroke volume with end-diastolic volume. The normal range is between 55 and 70 %.
  • A bruit is an audible vascular sound associated with turbulent blood flow, usually due to partial arterial obstruction. It can often be heard over the carotid arteries, abdominal aorta, renal arteries and femoral arteries.
    A bruit is indicative of atherosclerosis and arterial stenosis.
  • LDL carries cholesterol from the liver to cells throughout the body. High levels deposit in arterial walls, forming plaques and leading to atherosclerosis.
    HDL absorbs cholesterol, carrying it to the liver. High levels reduce heart disease and stroke risk, and help remove cholesterol from arterial plaques, slowing or preventing their growth.
  • Systolic Heart Failure occurs when the heart muscle doesn’t contract with enough force, reducing the heart’s ejection fraction. This is due to weakening of the heart muscle. It is caused by dilation of the left ventricle.
  • In diastolic heart failure, the heart contracts normally but the ventricles do not relax properly. This leads to them filling less between beats. Ejection fraction is often normal, but the heart still fails to pump enough blood. It is caused by hypertrophy of the left ventricle.
  • A pericardial effusion is the accumulation of fluid in the space between the heart and the pericardium. It can lead to cardiac tamponade, where the heart cannot contract and relax properly due to the restricted space.
  • Vitamin K Agonists such as Warfarin – inhibit the synthesis of Vitamin K Dependent Clotting Factors which are essential for blood clot formation. 
    Direct Oral Anticoagulants (DOACs) – Target specific proteins in the coagulation cascade such as Thrombin.
    Heparin – Enhances the activity of Antithrombin III
    Thrombin Inhibitors – Prevents the action of thrombin directly, which is the enzyme that converts fibrinogen into fibrin – the basic structural component of the blood clot.
  • Rheumatic fever is an inflammatory disease occuring after a Group A Strep infection such as strep throat or scarlet fever. Rheumatic Heart Disease occurs when the inflammatory process affects the heart valves, leading to stenosis or regurgtitation, typically affecting the mitral and aortic valves.
  • Coarse crepitations are low-pitched and wet sounding and often heard on inspiration and early expiration. They are associated with bronchitis (inflammation of the bronchi), bronchiectasis (permanent enlargement of airways), pulmonary oedema (fluid in the lungs) and pneumonia (nasty lung infection).
  • Fine crepitations are high pitched sounds like that of hair rubbing between fingers, heard at the end of inspiration. They are indicative of pulmonary fibrosis (stiffening of lung tissue), however they may also be heard at the base of the lungs in early congestive heart failure.
  • Pleural effusion is the accumulation of fluid in the layer outside the lungs. It often leads to dyspnoea, chest pain and cough. Percussing the area will reveal dullness. It may also lead to tracheal deviation.
  • Tracheal deviation can be caused by:
    Pneumothorax - presence of air in the pleural space.
    Haemothorax - presence of blood in the pleural space.
    Pleural Effusion - presence of fluid in the pleural space.
    Goiter - an enlarged thyroid gland.
    Atelectasis - collapsed lung.
  • Effective asthma treatment is reliant on:
    -An up to date Asthma Action Plan
    -Correct and efficient use of inhalers
    -Avoiding irritants like tobacco, mould and pet dander.
    -Controling comorbidities like obesity and sleep apnoea.
    -Management of side-effects.
  • Obstructive lung diseases are characterised by limited airflow due to narrowing of the airways, remodelling or destruction of lung tissue.
    Examples include Chronic Obstructive Pulmonary Disease (COPD), Asthma (four-eyes condition), and Bronchiectasis (permanently enlarged airways).
    On Spirometry there is reduced Forced Expiratory Volume at 1 second (FEV1) and a lower FEV1 to Forced Vital Capacity ratio.
  • Restrictive Lung Diseases are characterised by reduced lung volumes either from an inability of the lungs to expand fully or because of a decrease in the chest wall’s ability to expand.
    Examples include Pulmonary Fibrosis (stiffening of lung tissue), Pleural Effusion (fluid in the pleura) and Sarcoidosis (inflammatory cells in the lungs that produce granulomas).
    It is characterised by reduced lung compliance and will show reduced Total Lung Capacity on spirometry but a normal or even elevated FEV1/FVC ratio.
  • Beta-2 receptors are located in the lungs. Activation leads to bronchodilation and vasodilation. Non-selective Beta-Blockers inhibit the activation of these receptors. Many asthma medications are beta-2 agonists and are therefore contraindicated with beta-blockers.
  • The atopic march refers to the progression of allergic diseases from eczema to food allergies to hay fever to asthma.