Heart 3

oelomar's version from 2016-04-30 14:46


Question Answer
What is Marfan’s syndrome and what does it affect?Marfan’s syndrome is one of the most common autosomal inherited disorders of connective tissue affecting the heart, eyes, and skeleton.
How can Marfan’s syndrome affect the heart?Aortic aneurysm, dissection, and regurgitation; mitral valve prolapse and regurgitation.
How can Marfan’s syndrome affect the eyes?Lens dislocation, retinal detachments, glaucoma.
How can Marfan’s syndrome affect the skeleton?Tall, thin body build with long arms, legs, and fingers (arachnodactyly), scoliosis, high-arched palate, pectus excavatum/carinatum.
How is Marfan’s syndrome diagnosed?Two of three major systems must be affected to avoid overdiagnosing the condition. Diagnosis may be confirmed by studying family linkage to the causative gene, or by demonstrating a mutation in the Marfan’s syndrome gene.
What cardiac investigations can be undertaken in Marfan’s syndrome?Echocardiography shows mitral valve prolapse, and mitral regurgitation in the majority of patients. CT or CMR (cardiovascular magnetic resonance) detect aortic dilatation and are useful in monitoring.
How is Marfan’s syndrome managed?Beta-blocker therapy slows the rate of dilatation of the aortic root. ACE inhibitors can also be used as in Marfan’s there is upregulation of TNF-β, which is specifically inhibited by ACE inhibitors. Lifestyle alterations are required because of ocular, cardiac or skeletal involvement. Sports that necessitate prolonged exertion at maximum cardiac output, such as cross-country running, are to be avoided. Sedentary occupations are usually best, as patients tend to suffer from easy fatigability and hypermobile painful joints. Patients should also have yearly/6-monthly monitoring of the aortic root diameter with echocardiograms.
Are there any implications of patients with Marfan’s syndrome becoming pregnant?Pregnancy is generally well tolerated if no serious cardiac problems are present, but is preferably avoided if the aortic root diameter is over 4cm, with aortic regurgitation.


Question Answer
What is rheumatic fever?Rheumatic fever is an inflammatory disease that occurs in children and young adults (the first attack usually occurs at between 5 and 15 years of age) as a result of infection with group A streptococci. It affects the heart, skin, joints, and CNS. Pharyngeal infection with group A streptococcus is followed by the clinical syndrome of rheumatic fever (this is thought to develop because of an autoimmune reaction triggered by molecular mimicry between the cell wall M proteins of the infecting Streptococcus pyogenes and cardiac myosin and laminin. The condition is not due to direct infection of the heart or to the production of a toxin).
What are the clinical features of rheumatic fever?“FEVERSS”. Fever, Erythema marginatum (pink rings on torso and inner surface of the limbs), Valvular damage, raised ESR, Red-hot joints (migratory polyarthritis), Subcutaneous nodules (Aschoff bodies – nodules found in the hearts of individuals with rheumatic fever), St. Vitus’ dance (chorea).
What are the “major criteria” used in the diagnosis of rheumatic fever?Carditis, polyarthritis, chorea, erythema marginatum, subcutaneous nodules.
What are the “minor criteria” used in the diagnosis of rheumatic fever?Fever, arthralgia (unless arthritis counted as major criterion), previous rheumatic fever, raised ESR/CRP, leucocytosis, prolonged PR interval on ECG (unless carditis counted as a major criterion).
How is rheumatic fever diagnosed?Diagnosis relies on the presence of two or more major clinical manifestations or one major manifestation plus two or more minor features. These are known as the modified Jones criteria.
How can rheumatic fever affect heart valves?Can cause prolapse or stenosis of heart valves; mitral>aortic>>tricuspid (high-pressure valves affected most). The single most common valvular lesion is mitral stenosis.
What investigations can be carried out in rheumatic fever?Throat swabs are cultured for group A streptococcus, ESR and CRP are usually high, cardiac investigations (ECG, echocardiogram may show evidence of carditis).


Question Answer
What is infective endocarditis?An endovascular infection of cardiovascular structures, including cardiac valves, atrial and ventricular endocardium, large intrathoracic vessels, and intracardial foreign bodies (e.g. prosthetic valves).
What is the most common causative organism of infective endocarditis?Streptococcus viridans.
How is infective endocarditis diagnosed?Fever + new murmur = infective endocarditis until proven otherwise. The Duke’s criteria can also be used: blood cultures – at least three sets of samples should be taken from different sites (diagnostic); serological tests – aids diagnosis in cases where organisms will not grow in standard blood cultures; full blood count – mild normochromic normocytic anaemia; echocardiography – rapid, non-invasive, and has high specificity for visualising vegetations (abnormal growth).
What are the clinical features of infective endocarditis?The clinical presentation is dependent on the organism and the presence of predisposing cardiac conditions, but otherwise “FROM JANE”: Fever, Roth’s spots (round white spots on retina surrounded by haemorrhage), Osler’s nodes (tender raised lesions on finger or toe pads), new Murmur (could be due to valvular damage – mitral valve is most frequently involved; tricuspid valve endocarditis is associated with IV drug abuse), Janeway lesions (small erythematous lesions on palm or sole), Anaemia, Nail-bed haemorrhage (splinter haemorrhage on nail), Emboli.
What is the prognosis of infective endocarditis?Without treatment, the mortality approaches 100%, but even with treatment there is a significant morbidity and mortality.
How is infective endocarditis treated?Antibiotic therapy targeting the specific organism.


Question Answer
How is valvular disease diagnosed?Echocardiogram.
What causes mitral stenosis?Almost all are caused by rheumatic fever.
What are the signs/symptoms of mitral stenosis?Malar flush (plum-red discolouration of the high cheeks), shortness of breath on exertion, orthopnoea, fatigue, palpitations, peripheral oedema, pinched and blue facies (severe MS). Low-pitched “rumbling” mid-diastolic murmur is best heard with the bell of the stethoscope held lightly at the apex with the patient lying on the left side. Chronic MS can lead to left atrial dilation.
What is mitral valve prolapse?Also known as Barlow’s syndrome or floppy mitral valve, this is a valvular heart disease characterised by the displacement of an abnormally thickened mitral valve leaflet into the left atrium during systole. Mild mitral valve prolapse is so common that it should be regarded as a normal variant.
What is mitral valve prolapse syndrome?Mitral valve prolapse associated with symptoms, including atypical chest pain (most common symptom – usually the pain is left submammary and stabbing in quality), palpitations, dyspnoea on exertion, etc. It predisposes to infective endocarditis and can lead to mitral regurgitation.
What are the complications of severe mitral valve prolapse syndrome?Mitral regurgitation, infective endocarditis, CHF, and, in rare circumstances, cardiac arrest.
What is mitral regurgitation?Mitral regurgitation is leakage of blood backward through the mitral valve each time the left ventricle contracts.
What are the causes of mitral regurgitation?Rheumatic heart disease and a prolapsing mitral valve are the most common causes. It can also be caused by IHD and LV dilation.
What are the symptoms of mitral regurgitation?Dyspnoea and orthopnoea; fatigue and lethargy (because of reduced cardiac output); symptoms of right-sided heart failure in the late stages of the disease; subacute infective endocarditis.
What are the signs of mitral regurgitation?Laterally displaced diffuse apex beat and a systolic thrill (a thrill felt over the precordium (the region of the thorax immediately in front of or over the heart) on palpation during ventricular systole); soft first heart sound; pansystolic murmur loudest at the apex but radiating widely over the precordium and into the axilla; 3rd and 4th heart sounds.


Question Answer
What causes the first heart sound (S1)?Mitral and tricuspid valve closure – the “lub” of the “lub-dub”.
What causes the second heart sound (S2)?Aortic and pulmonary valve closure – the “dub” of the “lub-dub”.
What is a “split S2”?A finding upon auscultation of the S2 heart sound. It is caused when the closure of the aortic valve and the closure of the pulmonary valve are not synchronised normally. An S2 split heard during inspiration is physiologically normal.
What is a “paradoxically split S2”?This is heard on auscultation when the pulmonary valve closes before the aortic valve. It is seen in conditions that delay left ventricular emptying such as aortic stenosis and left-bundle branch block.
What is indicated by a “split S2” during expiration?Reverse splitting indicates pathology. Aortic stenosis, hypertrophic cardiomyopathy, left-bundle branch block, and a ventricular pacemaker could all cause reverse splitting of the second heart sound.
What causes the third heart sound (S3)?This is pathological. It occurs in the beginning of diastole after S2 and is lower in pitch than S1 and S2 as it is not of valvular origin. S3 is thought to be caused by the oscillation of blood back and forth between the walls of the ventricles initiated by blood rushing in from the atria, and is present in heart failure; ie it is due to rapid ventricular filling. An S3 heart sound is best heard with the bell-side of the stethoscope (used for lower frequency sounds).
What causes the fourth heart sound (S4)?This is pathological. The sound occurs just after atrial contraction at the end of diastole and immediately before S1. It is produced by the sound of blood being forced into a stiff or hypertrophic ventricle, and is a sign of a pathologic state, usually a failing or hypertrophic left ventricle, as in systemic hypertension, severe valvular aortic stenosis, and hypertrophic cardiomyopathy. Atrial contraction must be present for production of an S4.


Question Answer
What are the causes of tricuspid regurgitation?RV dilation or infective endocarditis (both of which can be caused by rheumatic fever).
What are the symptoms of tricuspid regurgitation?Patients may complain of the symptoms of right-sided heart failure (palpitations, fatigue, peripheral oedema).
What are the signs of tricuspid regurgitation?Palpable, pulsating liver (blood regurgitates into the venous system with systole); large jugular venous “cv waves” (giant systolic pulsations in JVP area); pansystolic murmur.
What are the causes of tricuspid stenosis?It is usually due to rheumatic heart disease and is frequently associated with mitral and/or aortic valve disease. Tricuspid stenosis is also seen in carcinoid syndrome.
Describe the murmur heard in tricuspid stenosis.There is usually a rumbling mid-diastolic murmur, which is heard best at the lower left sternal edge and is louder on inspiration. It may be missed because of the murmur of co-existing mitral stenosis.
What are some of the signs of tricuspid stenosis?Hepatomegaly (causing abdominal pain), ascites, peripheral oedema.
What are the causes of pulmonary stenosis?This is usually a congenital lesion, but it may rarely result from rheumatic fever or carcinoid syndrome.
Describe the murmur heard in pulmonary stenosis.Harsh mid-systolic ejection murmur, best heard on inspiration, to the left of the sternum in the second intercostal space. This murmur is often associated with a thrill.
Describe the murmur heard in pulmonary regurgitation.Decrescendo diastolic murmur.
What are the symptoms of pulmonary regurgitation?Pulmonary regurgitation usually causes no symptoms and treatment is rarely necessary.


Question Answer
Where would one auscultate for the “aortic area”?Second right intercostal space at the sternal border (where the ascending aorta is nearest the thoracic cage).
Where would one auscultate for the “pulmonary area”?Second left intercostal space at the sternal border (where the infundibulum is closest to the thoracic cage).
Where would one auscultate for the “tricuspid area”?Fourth left intercostal space at the sternal border (point closest to the valve in which auscultation is possible).
Where would one auscultate for the “mitral area”?Fifth left intercostal space at the mid-clavicular line (point where left ventricle is closest to the thoracic cage).
What is Erb’s point and what is best heard there via auscultation?This is the third intercostal space on the left sternal border where S2 is best auscultated.
When are systolic murmurs heard?Between the first and second heart sounds.
When are diastolic murmurs heard?After the second heart sound.

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