MDCT assesses patency of off-pump versus on-pump coronary surgery
Graft patency can be assessed before discharge with 64-multidetector CT (64-MDCT) in 80.8 percent of cases, and when MDCT is performed the ability to visualize grafts and assess patency is 98 percent, according to a poster presentation at the American Heart Association scientific sessions held this week in Orlando, Fla.

Mohamed Abdellaoui and colleagues at the Institut Hospitalier Jacques Cartier, Massy, France, conducted the survey, none of which had any disclosures.

The researchers said that prior to their study, off-pump coronary artery bypass surgery (CABG) has been shown to be at least as safe as on-pump CABG, but the graft patency rate with the technique was controversial. The aim of their study was to compare early graft patency following off-pump versus on-pump CABG using 64-MDCT.

The researchers investigated all patients undergoing CABG at Institut Hospitalier, who were prospectively included in the study. The researchers assessed for early postoperative graft patency by 64-MDCT performed before discharge, and they independently assessed for graft patency by two operators. They then compared the patency rate between off-pump and on-pump. The operator decided the choice of technique.

The researchers excluded any patient with atrial fibrillation and creatinine higher than140 µmol/l. Scan protocol was standardized using 64 by 0.625mm slice collimation, 400 ms rotation time and simultaneous electrocardiogram gating.

From December 2006 to May 2007, the researchers examined 134 patients with a median age of 66 years, but 11 patients were excluded due to arrhythmias or tachycardia despite beta-blockade and 15 due to unavailability of MDCT before discharge. As a result, MDCT was performed in 108 patients, 69 in the on-pump group and 39 in the off-pump group, an average of eight days after surgery. Age, sex and risk factors were similar in the two groups.

The number of grafts in the on-pump group was 188 compared to 125 in the off-pump group. There were a greater proportion of radial grafts used in the on-pump group, 11.2 compared to none. MDCT was able to assess graft patency in 98 percent of cases: 183 of 188 grafts on-pump (97 percent) and 123 of 125 off-pump (98 percent).

The researchers concluded that the graft patency rate in patients undergoing on-pump and off-pump CABG is similar in the postoperative period.