XV Congresso nazionale SIEC 2011

Uso dell’Imaging nella pratica clinica: dalla diagnosi alla tecnologia

La Risonanza Magnetica Cardiaca:

quando usarla come gold standard

G. Di Bella (Messina)

Napoli, 16 Aprile 2011

Università di Messina Dipartimento Clinico Sperimentale di Medicina e Farmacologia

CMR: Advantages

•No Ionizing Radiation==>Virtually Safe

•Multiplanarity

•Flow and Velocity Measurement

•Not conditioned by presence of Bone

•Controindications (PM dependent,device, Claustrophobia..)

•Long time of execution

•Need for Cardiac Gating

•Need for Compatible instrument

CMR: Disadvantages

CMR

CMR as gold standard

Accuracy

Differential diagnosis

Reserch tool

High spatial and temporal resolution

standardization of acquisition

high quality images

no geometric assumptions

high accuracy

good inter and intra-observer reproducibility

Relative high costs

Not available at bed side of patients

CMR: left ventricular function

SSFP cine MRI:

10-16 slices, 8 mm thickness, no

spacing (or 2 mm gap),

R-R: 30 phases,

CMR: left ventricular function

Starting from a horizzontal long axis view

using planes orthogonal to major left ventricular

axis (from center of mitral valve to apex)

QUANTITATIVE ASSESSMENT

• End-diastolic frame and end-systolic frame for each slice

• Trace left ventricular endocardial contour

• Trace left ventricular epicardial contour

• Trace right ventricular endocardial contour

Phase 1 Phase 10

Post-processing

CMR: left ventricular function

Ventricular volume is the sum of single volume from each slice

(cavity area x slice thickness)

Stroke volume = EDV-ESV

EF = Stroke Volume/EDV x 100

Ventricular mass = (epicardial volume - cavity volume) x 1.05 g/cm3 By G.D Aquaro. IFC

CMR: left ventricular function

Maceira et al JCMR 2006

CMR: left ventricular function

ARVC/D

ARVC/D

Ev

ent-

free

Su

rviv

al(%

)

0 200 400 600 800 1000 1200

Event-free Survival curve of RVA vs no-RVA

Time (days)

no-RVA

RVA

P<0.0001

100

98

96

94

92

90

88

86

Aquaro GD et al JACC 2010

Ev

ent-

free

Su

rviv

al(%

) no-RVA

RVA

100

98

96

94

92

90

88

86

Event-free Survival curve: no-RVA, Intermediate group, ARVC/D group

0 200 400 600 800 1000 1200

Time (days)

RVA-1 group

RVA-2 group

P<0.0001

P<0.003

Aquaro GD et al JACC 2010

Echocardiography 2010

Additive data from strain imaging

Semiautomatic Quantification of Left Ventricular Function by

2D Feature Tracking Imaging Echocardiography.

A Comparison Study with Cardiac Magnetic Resonance Imaging

Gianluca Di Bella, M.D., Ph.D., Concetta Zito, M.D., *Michele Gaeta, M.D., Maurizio Cusmà Piccione, M.D., *Fabio Minutoli, M.D.,

*Rocco Donato, M.D., Antonino Recupero, M.D., Antonio Madaffari, M.D., Sebastiano Coglitore, M.D., Scipione Carerj M.D.

Echocardiography 2010

Di Bella G, et Al. Echocardiography

Stroke volume can be assessed also

by measuring total flow

across ascending aorta or pulmonary

trunk in one heartbeat

CMR: left ventricular function

Stroke volume can be assessed also

by measuring total flow across

ascending aorta or pulmonary

trunk in one heartbeat

CMR: left ventricular function

Absolute Flow 86 ml/beat

Retrograd Flow 32 ml/beat

Regurgitant fraction 37%

Quantitative assessment of absolute aortic flow

(LV stroke volume)

CMR: left ventricular function

Quantitative assessment of absolute pulmonary flow

(RV stroke volume)

QP/QS

CMR: Flow measurements

Clinical Implication……………………..

Congenital heart diseases

Study of Left Ventricle volume and mass:

EndDiastolic Volume: 210 ml

EndSystolic Volume: 94ml

Stroke volume: 115 ml

EF 55%

Mass: 175 g

Phase Contrast at Ascending Aorta

Real Stroke volume 73.5 ml

REAL EF=SV/EDVx 100%

73.5/210x100

EF 35%

Regurgitant Volume=

115 ml-73.5 ml=41.5 ml Mitral regurgitation

CMR as gold standard

Identification and

extent of scar tissue

Scar tissue in myocardial infarction

Scar tissue in myocarditis

A. Wagner et al. Lancet 2003

necrosis as small as 1g can be detected with CE-IR-MRI

<=> 10 g with SPECT

Noninvasive Gold for Infarct Imaging ?

CE-IR MRI rationale: scarred myocardium strongly enhances

after Gd-DTPA administration, and can be used to

determine presence, extent, and transmurality, and

to differentiate with normal myocardium

(Kim et al. N Engl J Med, 2000)

likelihood of segmental recovery of function

paralles infarct transmurality

Il valore prognostico additivo dell’integrazione funzione/necrosi

HR P de=1 & wm=0 vs de=0 & wm=0 2,285 ns de=0 & wm=1 vs de=0 & wm=0 2,129 ns

de=1 & wm=1 vs de=0 & wm=0 7,784 0.007

de=1 & wm=1 vs de=1 & wm=0 3,347 0.05

de=1 & wm=1 vs de=0 & wm=1 3,407 0.05 Di Bella et al.

Submitted

237 pts con infarto miocardico pregresso con e senza

disfunzione ventricolare sinistra Eventi: n=19 (morte cardiaca, arresto resuscitato, scarica

DEF appropriata

Immagini T2 pesate Fase acuta

Immagini T2 pesate Fase cronica

Delayed Enhancement Fase cronica

Acute Myocarditis

CMR as gold standard

Tissue characterization

MIXOMA

Di Bella G et al. Rev Esp Cardiol. 2010;63(11):1383-9 ANGIOSARCOMA

Di Bella G et al. Circulation 2008

CMR as gold standard

Tissue characterization (scar tissue)

Myocarditis

Viability

Cardiac tumors

Cardiomyopathies

Cardiac Morphology andFunction

RV function

Congenital heart diseases

CMR is gold standard in

Right ventricular function

Identification of scar tissue in MI and

Myocarditis

Tissue caracterization of cardiac tumors

and in other many cardiomyopaties

Gianluca Di Bella

Grazie

University of Messina Clinical and Experimental Department of Medicine and Pharmacology

PhD course on Cardiovascular Imaging Methodologies and Techniques

Post-Infarction Ventricular

Arrhythmia

• Characterization of the peri-infarct zone by CE-MRI is a powerful predictor

of post-myocardial infarction mortality (Yan AT et al. Circulation 2006;114:32)

• Presence and extent of tissue heterogeneity in the peri-infarct zone increases

susceptibility to ventricular arrhythmias in patients with prior LV infarction

and LV dysfunction (Schmidt A et al. Circulation 2007;115:2006)

RV infarction

Grasso e Displasia aritmogena VD

“Un caso senza sospetti”

Immagini T1 pesate Immagini T1 pesate con fat suppression

Delayed enhancement

CMR: left ventricular function By G.D Aquaro. IFC

Epidemiologic data

•2% of population < 65 years

•10% of population > 65 years

have reduction of LV systolic function

CMR: left ventricular function

1 R-R

8-16 View per segm.

30 N° Phase

1 NEX

0.0 SPACING

8 mm THICKNESS

~40 FOV

125 kHz RBw

45° FLIP ANGLE

In base

freq.cardiaca TR

Minimun TE

SSFP

CMR: left ventricular function

dia

sto

le

sis

tole

Tagging RM

E1: ispessimento sistolico

E2: accorciamento circonferenziale

Alfa: angolo di deformazione della direzione di E1 rispetto alla

direzione radiale

E1

E2

Alfa

Clinical Implication……………………

• LV

• >>>>>> RV

• Global function

• >>> regional function

CMR as gold standard in

function

MRI tagging

Con una sequenza di

impulsi viene generata

una modulazione spaziale

di magnetizazzione.

Le righe generate si

muovonoi con il tessuto e

si analizza il movimento

delle righe (deformazione)

su più immagini

La sequenza di impulsi in CINE viene

preceduta da una modulazione spaziale di

magnetizzazione (demagnetizzazione)

Le righe generate (tags) si muovono con il

tessuto

viene analizzato la deformazione delle tags

line nelle fasi del ciclo cardiaco

mappe di deformazione del miocardio

MRI: STUDIO DI FUNZIONE

TAGGING

ECO RM

Fattibilità +++ ++

Sicurezza +++ ++

Acc Diagnostica ++ +++

Costi + +++

Tempo Esame + +++

Risol. Temporale +++ ++

Risol. Spaziale ++ +++

“Val. Quantitativa ++ +++

ECO vs RM

Study of Left Ventricle volume and mass:

EndDiastolic Volume: 210 ml

EndSystolic Volume: 94ml

Stroke volume: 115 ml

EF 55%

Mass: 175 g

Phase Contrast at Ascending Aorta

Real Stroke volume 73.5 ml

REAL EF=SV/EDVx 100%

73.5/210x100

EF 35%

Regurgitant Volume=

115 ml-73.5 ml=41.5 ml

CMR: Flow measurements

Mitral regurgitation

Clinical Implication……………………..

Di Bella G, et Al. In press Echocardiography

Semiautomatic Quantification of Left Ventricular Function by

2D Feature Tracking Imaging Echocardiography.

A Comparison Study with Cardiac Magnetic Resonance Imaging

MR in VALVULOPATIE

EDV: 328 ml; ESV: 140 ml;

ejection fraction: 57%; mass: 195 g

EF= 188/328*100= 57%

Real EF= 81/328*100= 25%

Regurgitation flow volume: 77 ml;

regurgitation fraction: 46%.

Effective aortic SV (156-77) = 81 ml;