structural cardiac abnormalities Flashcards
what is the most common primary cardiac tumour
atrial myxomas
what are atrial myxomas
most common primary cardiac tumour - rare heart tumour found in the top chambers (atria) of the heart. Around three quarters of atrial myxomas occur in the left atria. They tend to grow on the wall (septum) that separates the right and left sides of the heart. They are ‘benign’, which means they do not spread around the rest of the body like other cancerous tumours. The tumour may obstruct the mitral valve or may be a site of thrombi, which can embolise
what are the signs and symptoms of atrial myxomas
Patients may be asymptomatic or present with dyspnoea, syncope or a mild fever. Physical signs include a loud first heart sound, a tumour ‘plop’, a mid-diastolic murmur and signs of embolism
what are common cardiac benign tumours
atrial myxoma lipoma papillary fibroelastoma fibroma haemangioma
what are common primary malignant cardiac tumours
angiosarcoma
undifferentiated sarcoma
rhabdomyosarcoma
osteosarcoma
what is myocarditis
An acute or chronic inflammatory pathology. Acute inflammation of the myocardium of the heart
what are causes of myocarditis
- Mainly caused by enteroviruses - Coxsackie A and B and echovirus
- Idiopathic
- Infective: viral, parasitic, bacterial, spirochaetal, fungal
- Toxic: drugs, radiation
- Autoimmune
- Alcohol
- Hydrocarbons
what are clinical features of myocarditis
- Young adults
- Mild fatigue
- Palpitations
- Chest pain
- Dyspnoea
- Fulminant congestive cardiac failure
- Soft heart sounds
- Prominent 3rd sound
- Tachycardia
what are investigations of myocarditis
- ECG - AV block may be seen for Lyme disease, sarcoid, giant- cell myocarditis and Chagas disease
- Echo - may revel normal of reduced biventricular function with resting regional wall motion abnormalities
- Blood tests - include ESR and CRP which are frequently elevated in the acute presentation. Cardiac troponin and creatine kinase levels will be elevated
- CMR - patients with acute myocarditis may demonstrate myocardial oedema on T2- weighted images and patchy myocardial enhancement with gadolinium
- Endomyocardial biopsy
- Coronary angiography
management of myocarditis
- usually resolves within a few weeks
- if patients deteriorate then they may require urgent transfer to a cardiac centre with access to extracorporeal membrane oxygenation and/or cardiac transplant
- bed rest
what is giant cell myocarditis
- Severe form of myocarditis characterised by multinucleate giant cells within the myocardium
what is Chagas’ disease
- Caused by the protozoon Trypanosoma Cruzi
- features of acute myocarditis and fever and congestive heart failure
- Chronically there is progression to a dilated cardiomyopathy with a propensity towards heart block and ventricular arrhythmias
How is myocarditis diagnosed
Diagnosed by viral PCR.
Throat swab and stool for enteroviruses
Throat swab for influenza
what is cardiomyopathies
group of diseases of the myocardium that affect the mechanical or electrical function of the heart
what is Hypertrophic cardiomyopathy
Include a group of inherited conditions that produce hypertrophy of the myocardium in the absence of an alternative cause.
The majority of cases are familial autosomal dominate and are due to mutations in the genes encoding sarcomeric proteins
what is the most common cause of hypertrophic cardiomyopathy
Mutations of the beta-myosin heavy chain MYH7 and myosin binding protein C MYBPC3
what are the clinical features of hypertrophic cardiomyopathy
- Involves the inter ventricular septum and disorganisation of cardiac myocytes and myofibrils
- The salient clinical morphological features of the disease vary according to the underlying genetic mutation
what are symptoms if hypertrophic cardiomyopathy
- Many cases are asymptomatic and detected by family screening
- Chest pain, dyspnoea, syncope, cardiac arrhythmias and sudden death are seen
- Double apical pulsation (forced atrial contraction producing a fourth heart sound)
- Jerky carotid pulse because of rapid ejection and sudden obstruction to left ventricular outflow during systole
- Ejection systolic murmur due to left ventricular outflow obstruction in late systole
- Pansystolic murmur due to mitral regurgitation
- Fourth heart sound
what is the management of hypertrophic cardiomyopathy
- Chest pain and dyspnoea should be treated with a beta blocker and Verapamil, either alone or in combination
- In some individuals with significant left outflow obstruction and symptoms, dual chamber pacing is necessary
- Alcohol ablation of the septum has been investigated and appears to give good results in the reduction of outflow tract obstruction
- Occasional surgical resection of septal myocardium may be indicated
what is arrhythmogenic right ventricular cardiomyopathy
An autosomal dominant mutations in the genes for desmosomal proteins; autosomal recessive mutations in nondesomosomal genes
Fibrofatty replacement of cardiomyocytes in the RV
what are 3 subgroups of inherited cardiac conditions
- Cardiomyopathy
- Channelopathy
- Aortopathy
what are examples of Channelopathies
- Congenital Long QT syndrome
- Brugada syndrome
- Catecholaminergic Polymorphic Ventricular Tachycardia
- Short QT syndrome
what are examples of Cardiomyopathies
- Hypertrophic cardiomyopathy
- Arrhythmogenic Right ventricular cardiomyopathy
- Dilated cardiomyopathy
what is Dilated cardiomyopathy
Characterised by the dilation of the ventricular chambers and systolic dysfunction with preserved wall thickness
Familial DCM is predominantly autosomal dominant and can be associated with over 20 abnormal loci and genes. Many of these genes encoding cytoskeletal or associated myocyte proteins. Many of them have prominent associated features such as skeletal myopathy or conduction system disease.
Sporadic DCM can be caused by multiple conditions including myocarditis, toxins, autoimmune disorders, endocrine disorders, neuromuscular diseases
what are clinical features of DCM (Dilated cardiomyopathy)
- Heart failure
- Cardiac arrhythmias
- Conduction defects
- Thromboembolism
what is the management for Dilated Cardiomyopathy
- Conventional management of heart failure
- Cardiac resynchronisation therapy and ICDs in patients with NYHA III/IV grading
- Cardiac transplantation us appropriate for certain patients
what is left ventricular non-compaction
Associated with a sponge like appearance of the left ventricle. The condition predominantly affects the apical portion of the left heart ventricle and may be associated with congenital heart abnormalities
what is primary restrictive non-hypertrophic cardiomyopathy
There is normal or decreased volume of both ventricles with bi-atrial enlargement, normal wall thickness, normal cardiac valves and impaired ventricular filling with restrictive physiology but near normal systolic function
what are channelopathies
Channelopathies are diseases that develop because of defects in ion channels caused by either genetic or acquired factors. Mutations in genes encoding ion channels, which impair channel function, are the most common cause of channelopathies.
Abnormal cardiac cellular electrophysiology
Mainly effecting repolarisation - if there is an effect on the protein channels then there will be an effect on the cation potentials seen on the ECG
what is congenital long QT syndrome (cLQTS)
A genetic disorder with 1:2000 being carriers. An ECG shows QTc interval prolongation (>440ms males and >450ms females)
Hallmark arrhythmia is polymorphic VT (Torsades de Pointes VT)
There are 13 subtypes of LQTS(13 genes)
Autosomal dominant - Isolated LQT: Romano-Ward syndrome
Autosomal recessive - associated with deafness: Jervell and Lange Nielson syndrome
Explain the effects of cLQTS
- Arrhythmia is polymorphic VT (Torsades de Pointes VT)
- ‘Lone AF heart block’
- Primary presenting complaints = syncope, SCD in children and younger adults
