Imaging Flashcards
Myocarditis - imaging
**Echo **
* wall thickening, reduced LVEF, strain (can track progress)
MRI - Lake Louise Criteria:
* Main:
Myocardial oedema (T2 T2W images)
Non ischaemic myocardial injury (abnormal T1, ECV or LGE)
- Supportive
Pericarditis (effusion or abniormal LGE, T1 or T2)
LV systolic dysfunction (RWMA or global)
Endomyocadial biopsy - Gold Standard
* If progressive symptoms despite treatment or specific diagnosis saught (Giant cell, Eosinophilic myocarditis)
Sarcoid - Imaging - Overview and Echo
- Complex inflammatory condition of unknown aetiology - can affect any organ of the body
- 20-25% of sarcoid patients have cardiac involvement on biopsy
Cardiac Sarcoid
* Asymptomatic
* AV conduction disease
* Heart Failure
* Ventricular arrhythmias (sudden death)
Cardiac complications are the leading cause of death in patients with sarcoid
Treatment
* Prolonged high dose steroids
Diagnosis
* Biopsy lacks sensitivity due to sampling bias (20-30%), as does serum ACE
* Advanced multimodality imaging required for diagnosis (echo/CMR/PET)
* Granulomas - inflammation and fibrosis. Anywhere in myocardium but particularly basal septum
Echo
* Early
Wall thickening (oedema), diastolic dysfunction
* Late
Wall thinning (scar), RWMA, systolic dysfunction
Poor sensitivity (25-65%)
Normal echo does not exclude
Sarcoid - Imaging - MRI and PET
Amyloid - Imaging - Echo
- Concentric hypertrophy, very commonly asymmetic (sigmoid septum or ISC)
- Atrial dilatation
- Speckled appearance of myocardium
- Preserved LVEF but reduced long axis function
- Restrictive filling pattern
- Pleural or pericardial effusions (more common in AL)
- Reduced LV strain - preserved in apical segments - bullseye appearance
Amyloid Imaging - MRI
- Subendocardial or transmural LGE
- Abnormal gadolinium kinetics (myocardium and blood pool black at the same time, subendocardial and epicardial LGE with dark middle “zebra striping”)
- ECV ≥40% - strongly suggestive but not diagnostic. T1 map can be used to track changes and is prognostic in ATTR and AL
Amyloid Imaging - 99m Tc-DPD (bone) Scintigraphy
- High sensitivity and specificity for ATTR
- Grade 1 - mild cardiac uptake, no attenuation of bone
- Grade 2 - moderate cardiac uptake, greater than bone
- Grade 3 - strong cardiac uptake, with little or no bone signal
If **grade 2 or 3 **and negative serum and urine immunofixation and serum free light chains –> diagnostic of ATTR amyloid
Include SPECT in protocol
If ATTR confirmed, ATTR genotyping (wild type vs variant)
HCM - Aetiology and Diagnosis
Diagnosis
* * In adults, LV wall thickness ≥15mm in 1 or more myocardial segments on echo/MRI/CT that is not solely explained by loading conditions
* In first degree relatives of patients with definitive HCM, ≥13mm
60% of cases, autosomal dominant transmission, caused by mutation in cardiac sarcomere proteins genes
Sarcomere genes
* Beta-myosin heavy chain MYH7
* **Myosin binding protein C **MYBPC3
These have higher rates of FHx, SCD, present earlier, more severe hypertrophy, increased fibrosis and poor prognosis
- Troponin T and I (TNNI3 and TNNT2)
- Tropomyosin alpha 1 (TPM1)
HCM - rare variants
Metabolic
* Anderson-Fabry’s Disease
* Gamma2 subunit of adenosine monophosphate receptor kinase (PRKAG2). 0.5-1% of HCM
* Danon Disease - lysosome-associated membrane protein 2 (LAMP2) 0.7-2.7% of HCM
Mitochondrial
* Respiratory chain protein complexes. MELAS, MERRF
Neuromuscular
* Friedrich’s ataxia
* Some other muscuolar dystophies and congenital skeletal myopathies (nemaline myopathy)
* FHL-1 mutations
* Occasionally desmin mutations (usually DCM or RCM)
Malformation Syndromes
* Usually MAPK mutations
* Noonan, LEOPARD, Costello
Infiltrative
* Amyloid
**Endocrine **
* Gestational DM (in the infant)
* Acromegaly
* Phaeochromocytome
Drugs
* Tetracylcines
* Hydroxychloroquine
HCM - ECG features of specific diagnoses
HCM - distinguishing from hypertensive heart disease
Favours HTN only
* Normal 12 lead ECG or isolated increased voltage witout repolarisation abnormality
* Regression of LVH after 6-12 months of tight BP control (SBP <130)
Favours HCM
* Family history of HCM
* RV hypertrophy
* LGE at RV insertion point or isolated to areas of maximum wall thickness
* Maximum wall thickness ≥15mm (caucasian), ≥20mm (black)
* Severe diastolic dysfunction
* Marked repolarisation abnormalities, conduction disease or Q waves
HCM - genetic testing
- Genetic testing should be done in patients who fulfil diagnostic criteria for HCM where it will facilitate family screening
- Patients with borderline HCM criteria - only genetically test after specialist team assessment
- Genetic testing should be done post mortem on pathologically confirmed HCM to allow for family screening
- Genetic testing (after counselling) in all first-degree adult relatives of patients with definite disease cuasing mutation
- If same genetic mutation in family member, clinical, ECG and echo follow up
- If the genetic mutation of proband not seen in family member - discharge family member
- If no definite gene mutation in proband, consider clinical assessment of relatives with ECG and echo every 2-5 years
HCM - syncope
- HCM diagnosis, syncope, high risk of sudden death –> ICD
- HCM diagnosis, syncope, low risk of sudden death –> ILR
- Syncope or symptoms with documented persistent or recurrent SVT or pre-excitation –> EPS +/- ablation
HCM - LVOTO
Diagnosed with LVOT gradient ≥30mmHg, clinically significant leading to treatment ≥50mmHg.
- General: Avoid dehydration, avoid alcohol, lose weight
- Drug Therapy: Non-vasodilating BB OR non-DHP CCB AND disopyramide (n.b. anticholinergic side effects)
- Invasive:
For patients with LVOT gradient ≥50mmHg, NYHA III-IV, and /or recurrent exertional syncope.
Ventricular septal myectomy (Morrow) +/- MVR
Alcohol septal ablation is an alernative. MDT decision
HCM - AF
- Warfarin for all, lifelong, unless prohibitive bleeding risk. Don’t use CHADS2VASc. If can’t use warfarin, DOAC
- Unstable - DCCV.
- Chest pain or heart failure - amiodarone or IV BB
- Stable - BB or non-DHP CCBs
- If LVOTO and normal EF, avoid digoxin
- Avoid flecainide and propafenone
- V Rate control - BB or non-DHP CCBs. Refractory - ablate AV node and pace (CRT-P in impaired LV function)
- V rhythm control - amiodarone, BB, CCBs. Refractory symptoms, no severe LA dilatation - consider ablation
- In HCM and sinus rhythm but LA ≥45mm, consider 48 hour holter every 6-12 months to detect AF
HCM - SCD risk factors
- Age (increased risk in the young)
- NSVT - ≥3 consecutive beats, ≥120bpm
- Maximum LV wall thickness. Severity and extent of LVH associated with SCD. Greatest risk in ≥30mm. Paradoxical reduced risk in thickness ≥35mm. Small number of patients. Use with caution.
- FHx SCD - ≥1 first degree relative <40 with sudden death with or without HCM diagnosis or SCD at any age in fisrst degree relative with HCM diagnosis
- Syncope - more predictive within 6 months of evaluation
- LA diameter
- Exercise BP response - <20mmHg increase from rest to peak exercise or fall >20mmHg from peak pressure
Arrhythmogenic Cardiomyopathy
DSP (desmophillin) - Causes LV predominant AVC
PKP2 - commonest in western patient. RV predominant AVC
If ICD needed - usually transvenous ICD so ATP can be given
Rx: Sotalol and mixiletine
