Internal thoracic artery graft (ITAG): patency and functional status at rest and during dobutamine-stress echocardiography.
BACKGROUND
The patent internal thoracic artery graft (ITAG) usually has a diastolic fraction (DF) > 50% of the flow. The functional assessment can be evaluated by the coronary reserve index (CRI).


OBJECTIVE
The objective was to evaluate the patency and functional status of the ITAG through echocardiography and Doppler.


METHODS
Data from sixty-six patients who underwent dobutamine-stress echocardiography (DSE) were prospectively collected and analyzed. Group I (GI) had 49 ITAG without stenosis, Group II (GII), 10 ITAG with significant stenosis (> 50% and <100%) and Group III (GIII) had 7 ITAG with total occlusion. Diameters and Doppler spectrums from the ITAG at rest and during DSE were evaluated.


RESULTS
Considering patency a DF >50%, it was observed in 49 ITAG (GI= 40, GII= 8 and GIII= 1) at rest and in 61 ITAG (GI=49, GII=10 and GIII=2) during DSE. The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and accuracy were respectively, 81%, 86%, 98%, 35% and 82%, and 100%, at rest and 71%, 97%, 100% and 97% in the DSE. The ITAG with DF>50% at rest were patent and the ones with DF<50% in the DSE presented total occlusion. Considering a CRI>1.8 for a good functional status, it was observed in 42 ITAG (39 from GI, 2 from GII and 1 from GIII), determining sensitivity=79%, specificity=85.7%, PPV=94%, NPV=59% and accuracy= 80.9%. The CRI in GI was higher (p= 0.02) than in GII or GIII.


CONCLUSIONS
In our study, the non-invasive assessment of the ITAG was effective to verify the patency and the functional status.
Abreu
José Sebastião de
JS
Hospital Prontocárdio de Fortaleza, Fortaleza, CE, Brasil. jsabreu@cardiol.br
Diógenes
Tereza Cristina Pinheiro
TC
Abreu
André Luís de Castro
AL
Barreto
José Erirtônio Façanha
JE
Morais
José Maria Bonfim de
JM
Abreu
Marília Esther Benevides de
ME
Pinto
Jorge Henrique Azevedo
JH
Paes Júnior
José Nogueira
JN
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001783:Blood Flow Velocity / Q000502:physiology; D001026:Coronary Artery Bypass / Q000009:adverse effects; D003971:Diastole / Q000502:physiology; D004280:Dobutamine; D015150:Echocardiography, Doppler / Q000592:standards; D025401:Echocardiography, Stress / Q000592:standards*; D004812:Epidemiologic Methods; D005260:Female; D006083:Graft Occlusion, Vascular / Q000000981:diagnostic imaging / Q000503:physiopathology*; D006801:Humans; D008297:Male; D008323:Mammary Arteries / Q000000981:diagnostic imaging / Q000502:physiology* / Q000637:transplantation*; D008875:Middle Aged; D012016:Reference Values; D012146:Rest; D014654:Vascular Patency / Q000502:physiology*; D014665:Vasodilator Agents
D014665:Vasodilator Agents; D004280:Dobutamine