EVALUATION OF AN ACTIVE CORONARY PERFUSION BALLOON DEVICE USING DOPPLER FLOW WIRE DURING PTCA

The aim of this study was to assess whether active coronary perfusion catheters (APC) can provide a sufficient coronary flow in large calibe r vessels during balloon inflation. To prevent myocardial ischemia dur ing PTCA, these APC may be employed. However, it is as yet unknown whe ther the active flow rate of these devices approaches the flow rate pr ior to PTCA during balloon inflation. Therefore, we measured the effic acy of the APC during balloon inflation in vessels supplying a large a mount of myocardium. In 12 patients (1 female, 11 males, 53 +/- 12.6 y r) with stenosed vessels (average diameter 3.4 +/- 0.26 mm), the coron ary flow velocity was measured using a 0.014 '' Doppler guidewire, whi ch was placed distally bypassing the balloon of the APC. The active pe rfusion balloon catheter was advanced through a 7F guiding catheter al ong a 0.014 '' guidewire. After removal of the guidewire, arterial blo od being withdrawn from the side port of the femoral angioplasty sheat h was pumped through the catheter to the distal coronary vessel. The p erfusion volumes of the pump were set to different levels between 30 t o 60 ml/min. Intracoronary flow rate was calculated by the angiographi cally assessed vessel luminal area average peak velocity * 0.5. The mean coronary flow rate prior to PTCA was 43 +/- 17.7 ml/min. Maximum flow during PTCA was 55 +/- 19.6 ml/min. We found a good correlation b etween the preset external pump rate and the coronary flow in situ (r = 0.92). Pre-PTCA flow rates were achieved in 11 of 12 patients (92%) during balloon inflation. No relevant decrease in the arterial pressur e occurred during dilation times of 4.6 +/- 1.63 min. Only two patient s showed significant ECG changes during these balloon inflations. Afte r an average follow-up period of 13 +/- 6.3 mo, only one patient (8%) had a significant re-stenosis requiring the implantation of a stent. T he combination of intravascular Doppler velocity measurements with qua ntitative coronary angiography offers the opportunity of exact online flow registration during angioplasty. Using APC, it is possible to mai ntain a sufficient coronary flow in the distal vessel during balloon i nflation even in large vessels. Therefore, as compared with mechanical circulatory assist devices, coronary assist by APC Is a little invasi ve, but according to our measurements it might be a sufficient tool fo r performing PTCA also in high-risk patients. (C) 1997 Wiley-Liss, Inc .