powerpoint presentation · 6/18/2016 1 advanced cardiac imaging for cardiomyopathies keyur b. shah,...

6/18/2016

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Advanced Cardiac Imaging for

Cardiomyopathies

Keyur B. Shah, M.D.

The Pauley Heart Center

Richmond, VA 6/24/2016

Disclosures

DateFooter 2

Research Grants: St. Jude, Novartis, Alynlam

Consultant: HeartWare Inc, Alnylam

Outline

Off the record disclaimers

Technology Overview

Clinical Pearls for Non-ischemic Cardiomyopathies

I am indebted too…

• Dr. John Grizzard MRI images

• Dr. Melvin Fratkin and Dr. Jordana Kron Nuclear Images

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MRI Physics (simplified version)

Takes advantage of the magnetic field generated hydrogen atoms (abundant in body)

Magnetic Field

RF

Pu

lse

Administer RF

Pulse, tilt nuclei of

axis

h

h

h

h

h

h

Magnetic Field

Hydrogen Nuclei

align under MRI

magnet

h

h

h

h

h

Magnetic Field

Protons lose energy and

emit measurable RF

signal

cMRI: Key points

Standard images in various planes

• Morphology (“black blood images)

• Function (“white blood images”)

Delayed enhancement images

Technical challenges

• Gating to rhythm poor gating , inaccurate

information

• Body size / clausterphobia

• Metal (some pacemakers are ok!!)

• Breath hold

• Renal impairment (risk of nephrogenic

systemic fibrosis)

cMRI: Standard Views

+ Delayed

Enhancement

The short-axis (SAX) cine stack is acquired from the base to the apex.

2 chamber view

(vertical long axis)3 chamber or LV outflow tract view 4 chamber view

(horizontal long axis)

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cMRI: What is Delayed Enhancement?

Late gadolinium enhancement (LGE) or delayed gadolinium enhancement (DGE)

Differential Washout Kinetics:

• Normally accumulates in interstitium, not in intact myocytes

• Gad enters and washes out of normal myocardium synchronously

• Cell injury, infiltration or fibrosis, increase the volume of distribution of Gad; Gad will lag

behind in these areas

LGE after Myocardial Infarction: Scar

Kim et al, Circ 1999

We are not this advanced

T1 Mapping (fibrosis)

T2 Mapping (edema)

Flow velocity encoding (measuring flow)

Spectroscopy (metablolism)

Tagging (regional myocardial function)

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Nuclear Imaging Principals

Radiotracer

1. Biological properties

2. Emits Photons

Gamma Camera

Captures Photons,

Photomultiplier converts

signals to image

Collimator helps localize

signal

Nonischemic

Cardiomyopathies

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Dilated Cardiomyopathy

Courtesy of Dr. John Grizzard

Dilated Cardiomyopathy


Mid-myocardial enhancement = fibrosis

Assomull RG. J Am Coll Cardiol. 2006;48:1977-1985.

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Midwall fibrosis:

• Larger ventricles

• Late stage disease

• Worse survival

• More SCD / VT

• More hospitalization

Assomull RG. J Am Coll Cardiol. 2006;48:1977-1985.

Myocarditis

Kindermann I. J Am Coll Cardiol. 2012;59(9):779-792.Arbustini E. Heart. 2000 Jan; 83(1): 86–90.

Pre and Post-contrast images


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Epicardial Enhancement

Not a CAD pattern


Infarct Myocarditis


Myocarditis

Herpes simplex 6 said to favor the septum


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Pre and Post-contrast images


Increase T2 Signal: Identifies Myocardial Edema

Kadkhodayan A. JACC Cardiovasc Imaging. 2016 May;9(5):603-17.

http://www.rcsb.org/pdb/

Protofibrils

Β-pleated sheat

Protein

Amyloidosis

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cMRI for Amyloidosis


Normal TI

Scout Amyloid


Amyloidosis

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Normal TI

Scout

The blood pool “nulls” before the

myocardium

Amyloid

MRI

Diffuse late gadolinium enhancement

Maceira AM. Circulation. 2005;111: 186-193.

Vokelsberg H. . JACC. 2008; 51:: 1022 - 1030.

Tc imaging for TTR Cardiac Amyloidosis: Perugini Grading

Images courtesy of: James Gillmore, MD25

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An Algorithm for Amyloid Heart Disease

Adapted from: Shah KB, et al. Circ Heart Fail. 2016;9:e002558.

Left Ventricular Hypertrophy on Echocardiography

Evaluate for Plasma Cell Dyscrasia / AL Amyloidosis

Evaluate for ATTR Amyloidosis

Unlikely Cardiac Amyloidosis

Nuclear Imaging(99mTc-DPD /99mTc-PYP/99mTc-HDP)

“Red Flag”

Referral to Hematology/Oncology

Likely ATTR Cardiac Amyloidosis

Genetic Testing for Transthyretin Mutation

Senile ATTR Hereditary ATTR

Cardiac Amyloidosis

No Cardiac Amyloidosis

(Discretionary) Pursue Tissue Diagnosis

Fat Pad Aspirate or other non-cardiac biopsy

(moderate sensitivity)

Endomyocardial Biopsy(high sensitivity)

&

- +

+-

-

-+

+

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Sarcoidosis: Pathophysiology

Tavora et al. Am J Cardiol 2009;104:571-577.

Localization of DE in Cardiac Sarcoid

Involvement often patchy and may be multifocal

Anteroseptal and lateral basal involvement often reported

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Nuclear Imaging

Pefusion agent: Where there is blood flow and myoctyes exist (no Scar)

Metabolism: Inflammation (active Sarcoid) has increased uptake (Gallium or FDG )

Kadkhodayan A. JACC Cardiovasc Imaging. 2016 May;9(5):603-17.

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PET/CT : fuse imaged

Hypertrophic Cardiomyopathy

The most common hereditary CV disease

• >1500 possible mutation in 11 different

genes

– Sarcomere

– Z- Disc

• Heterogeneous Morphologies

LVH in the absence of a loading stimuli

Exclusion of phenocopies

Prevalence Increasing

cMRI

•Borderline cases

•Localized Hypertrophy

(20 % of cases)

•Distinguishing Apical

HCM vs LVNCC


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Pathophysiology

Dyspnea

Syncope

Sudden

Death

Increased Wall

Thickness

Outflow

Obstruction

Mitral

Regurgitation

Arrhythmias

Ischemia

Angina

LGE with HCM

Typically involves septal insertion point to RV

Large Study

• In series of 1293 HCM patients

• Followed for 3.3 years

• Increased risk once > 15 %

Chan RH. Circulation. 2014 Aug;130(6):484-95.

Arrhythmogenic RV dysplasia (ARVD)

• Underlying lesion –mutation in genes coding for desmosomalproteins

• Fatty or Fibrofatty replacement of RV myocardium

• Typical presentation is VT with a LBBB pattern, syncope, or “sudden death” episode

Mcgregor SM Arch Pathol Lab Med. 2015

Sep;139(9):1181-6.

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ARVD

MRI Cine imaging is helpful

Abnormal wall motion, focal areas of

dyskinesia, ballooning of the RVOT, small

aneurysms

Mcgregor SM Arch Pathol Lab Med. 2015

Sep;139(9):1181-6.

ARVD


ARVD

Note enhancement of RV free wall at site of abnormal signal intensity


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Hemochromatosis

Hemochromatosis


T2 measurement

Carpenter JP. Circulation. 2011;123:1519-1528

h

h

h

h

h

Magnetic Field

Protons lose energy and

emit measurable RF

signal

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Thank you!!Questions?

powerpoint presentation · 6/18/2016 1 advanced cardiac imaging for cardiomyopathies keyur b. shah,...

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