The mean QAcorr (mL/minute per 1.73 m2) was 562 (+/- 290) in the VAT group and 1,005 (+/- 372) in the no VAT group, (p=0.02), meaning that it was significantly lower for patients with subsequent VAT.
The VAT rate was significantly lower in the UD era than in the pre-UD era. There were 4.1 VAT/patient-months in the UD era versus 11 VAT/patient-months in the pre-RD era, (p=0.03).
The VAT rate in the rapid referral period (from November 2000; 0.96 per 100 patient-months) was significantly lower than the rates observed in both the pre-UD era, (p=0.001), and the pre-rapid referral period of the UD era, (p=0.02).
No difference was noted in the mean double-pool Kt/V between the pre-UD era (1.20 +/- 0.16) and the UD-era (1.22 +/- 0.16), (non significant). There was also no difference in the mean double-pool Kt/V between patients with VAT (1.22 +/- 0.18) and those without VAT (1.22 +/- 0.14), (non significant).
The mean percentage change double-pool Kt/V from the two months prior to VAT (measured to assess whether there was a decrease in double-pool Kt/V prior to VAT) was -2.3% +/- 9.8% (range: -27.6 - 22.9).
In terms of the number of surgical procedures, 13 patients received 28 surveillance venograms in the pre-UD era, during which 13 angioplasty procedures were performed. Seven patients received 8 angioplasty procedures in the UD era.
Angioplasty resulted in significant improvements in QACcorr in the UD era, from 393 (+/- 155) to 850 (+/- 215) mL/minute per 1.73 m2, (p<0.001).
No patient in the UD era developed a VAT in the month after angioplasty.