Heart 7 inflammatory and structural disorders Flashcards
Inflammatory diseases of the heart
Any 3 layers of the heart can b einfected
many infections that will be discussed are preventable
disease are named after the layer of the heart that is inflacted
Complications include valvular damage, thromboembolic disease,
pulmonary hypertension, arrhythmias, heart failure and potentially
dea
“Acute Rheumatic Fever
is an illness caused by an immunological
reaction to infection with the bacterium group A streptococcus (GAS). It
causes an acute, generalised inflammatory response, and is an illness that
affects only certain parts of the body, mainly the heart, joints, brain and
skin. Individuals with ARF are often severely unwell, in great pain and
require hospitalisation. Despite the dramatic nature of the acute episode,
ARF leaves no lasting damage to the brain, joints or skin.
Rheumatic Heart Disease
the damage to the heart, or more specifically, the mitral and/or
aortic valves, may remain once the acute episode has resolved. This is
known as RHD
Rheumatic Fever and Rheumatic Heart Disease pathophysiology
Not everyone susceptible to ARF
• Only some forms of Group A streptococcus are rheumatogenic
• Autoimmune response to haemolytic streptococci in susceptible patients
• Risk increased for people of lower socio-economic groups, living in overcrowded conditions or
malnourished
• Caused by streptococcal infections of the pharynx
Infective
Endocarditis
nfection of a native or
prosthetic heart valve, the
endocardial surface, or an
indwelling cardiac device
Infective Endocarditis epidemiology
Rheumatic heart disease is a key risk factor for IE
• Degenerative valve disease, diabetes, cancer,
intravenous drug use, congenital heart disease
and renal dialysis are major risk factors for IE in
high-income countries.
• Patients on immunosuppressive therapy or
cortico-steroids may develop fungal endocarditis
Pathogenesis of infective endocardit
Bacterial entry
Baterial adherance to damage epithelium
Bacterial proliferation, neutrophil and macrophages infiltration
Vegatation formation
Infective
Endocarditis causative agents
Staphylococcus • Streptococcus • Enterococci • Fungi (candida, aspergillus) • Viruses
Risk Factors for Infective Endocarditis
Cardiac and non cardiac
Cardiac
• Prosthetic heart valve* • Pervious infective endocarditis* • Congenital heart disease* • Rheumatic heart disease • Degenerative valve disease • Cardiac transplant with valvulopathy • Implantable electronic cardiac device (pacemaker or defibrillator) • Hypertrophic cardiomyopathy
non cardiac
Haemodialysis • Diabetes mellitus • Injected drug use • Indwelling venous catheters • Immunosuppression • Poor oral hygiene • Genetic disorders (i.e. Marfan’s syndrome)
Signs and Symptoms
Infective Endocarditis
Can involve multiple organs • Consider in anyone with sepsis of unknown origin or fever with known risk factors • Cardiac murmur • Chills • Weakness • Malaise • Fatigue • Anorexia • Vascular symptoms • Splinter haemorrhages • Petechiae • Oslers nodes • Janeway’s lesions • Secondary signs and symptoms • Embolisation to spleen may cause sharp pain in LUQ and tenderness and rigidity • Embolisation to kidneys may cause flank pain, haematuria and renal failure • Embolisation to brain = neurologic S & S • Embolisation to legs = ischaemia and gangrene • Embolisation to lungs = PE (dyspnoea, chest pain, haemoptysis and respiratory arrest
Diagnosis Infective Endocarditis
• Good clinical assessment needed including health history • Blood cultures x 2 (different sites) • New or changed heart murmur • Transthoracic echocardiogram (TTE) • Transoesophageal echocardiogram (TOE) • CT/MRI • ECG – 1 st or 2nd degree HB
Multidisciplinary Care and Management
Antibiotics
Surgery
Antibiotics
Start as soon as blood cultures acquired
• Modify according to culture results, resistance
patterns, severity of infection and presence of
absence of prosthetic material
• Combination therapy preferred (in general)
• Parenteral AB treatment usually lasts 4-6
weeks to ensure eradication of causative
organism
