Chronic total coronary occlusion in patients with intermediate viability: value of low-dose dobutamine and contrast-enhanced 3-T MRI in predicting functional recovery in patients undergoing percutaneous revascularisation with drug-eluting stent.
OBJECTIVE
Myocardial viability was evaluated by magnetic resonance imaging (MRI) in patients with chronic total coronary occlusion (CTO) treated with a drug-eluting stent. Change in left ventricular ejection fraction (LVEF) was analysed.


METHODS
Twenty-three patients with CTO underwent delayed-enhancement (DE) and low-dose dobutamine MRI (LD). Diastolic wall thickness (DWT), dobutamine-induced systolic wall thickening (SWT) and DE transmural extension were quantitatively assessed in vessel-related segments, calculating the contribution of viable tissue to SWT, expressed as viability index (VI)=[SWTx(100 - DE)]/100. Patients with transmural enhancement were excluded from revascularisation. At 6 months follow-up, patients underwent coronary angiography (CA) and MRI. Functional recovery was defined as a 2-mm increase in SWT.


RESULTS
Transmural enhancement (mean DE 62.88+/-37.18] was present in three patients. Mean DWT, SWT, VI and DE of recanalised patients were 8.03+/-2.35, 2.64+/-1.56, 1.77+/-1.48 mm and 41.97+/-30.32. Revascularisation was successful in 14/16. Follow-up CA showed patency of treated vessels. Functional recovery was achieved in 13 patients. Functional recovery showed significant correlation with SWT (beta 1,779, p=0.015), and even higher correlation with VI (beta 2.032, p=0.011). LVEF improved significantly [Delta 95% confidence interval (CI) -4.47, p=0.0203).


CONCLUSIONS
Invasive CTO treatment has beneficial effects on myocardial contractility that can be predicted by VI, and on LVEF.
Fiocchi
F
F
Dipartimento Integrato dei Servizi Diagnostici e per Immagine, Cattedra e Servizio di Radiologia 1, Università degli Studi di Modena e Reggio Emilia, Azienda Ospedaliero Universitaria Policlinico, Modena, Italy. federica.fiocchi@gmail.com
Sgura
F
F
Di Girolamo
A
A
Ligabue
G
G
Ferraresi
S
S
Rossi
R
R
D'Amico
R
R
Modena
M G
MG
Torricelli
P
P
D000368:Aged; D002316:Cardiotonic Agents; D002908:Chronic Disease; D003287:Contrast Media; D023921:Coronary Stenosis / Q000503:physiopathology / Q000628:therapy*; D004280:Dobutamine; D054855:Drug-Eluting Stents; D005260:Female; D006571:Heterocyclic Compounds; D006801:Humans; D016014:Linear Models; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D009204:Myocardial Revascularization; D009942:Organometallic Compounds; D011237:Predictive Value of Tests; D020127:Recovery of Function; D016896:Treatment Outcome
D002316:Cardiotonic Agents; D003287:Contrast Media; D006571:Heterocyclic Compounds; D009942:Organometallic Compounds; D004280:Dobutamine; C050823:gadolinium 1,4,7,10-tetraazacyclododecane-N,N',N'',N'''-tetraacetate