Quantitative evaluation of selective thrombolysis techniques: Influence of catheter characteristics and delivery parameters

✍ Scribed by Roy, Sumit ;Lærum, Frode ;Brosstad, Frank

• Publisher: John Wiley and Sons
• Year: 1998
• Tongue: English
• Weight: 98 KB
• Volume: 43
• Category: Article
• ISSN: 0098-6569
• DOI: 10.1002/(sici)1097-0304(199801)43:1<111::aid-ccd32>3.0.co;2-q

✦ Synopsis

Here, we evaluate in vitro the site-specific delivery ability of thrombolysis catheters and compare continuous infusion (CI) and periodic injection (PI) protocols with reference to this parameter. Thrombotic occlusion was simulated by placing a porcine blood clot proximal to an eccentric stenosis in a flow phantom. Iodinated contrast agent was used as the marker. Part I-Evaluation of thrombolysis catheters: four CI and three PI catheters were tested. The marker was delivered as an infusion at 1 ml/min for 1 min (CI), or as two 0.25 ml boluses 30 sec apart (PI). Iodine content of the clot was then estimated with x-ray fluorescence spectrometry. This value as a ratio of the delivered dose was defined as the targeting efficiency. Part II-Evaluation of thrombolysis protocols: CI and PI were compared. The marker was delivered for 3 or 5 min using one of seven protocols. The iodine content of both clot and effluent were estimated. Among PI catheters, the Jet-Lysis catheter proved to be the best (P ‫؍‬ 0.02). The EDM catheter had the lowest targeting efficiency in the CI group (P ‫؍‬ 0.01). With CI, median iodine recovery dropped from 0.21 (95% confidence interval: 0.08, 0.25) for 1 min to 0.13 (0.05, 0.16) for 3 min and 0.07 (0.03, 0.10) for 5 min; for PI the values remained unchanged. The fraction lost in the effluent increased with the duration of regimen with both CI (P ‫؍‬ 0.014) and PI (P ‫؍‬ 0.004). Reducing the rate of infusion or the bolus frequency resulted in major improvements with respect to this parameter (P ‫؍‬ 0.005). For CI, the targeting efficiency increased as well (P ‫؍‬ 0.03). We conclude that currently used thrombolysis protocols do not fully exploit the delivery advantage offered by CI or PI. Fortunately, simple modifications offer the possibility of overcoming these drawbacks.