Intracoronary pressure and flow velocity with sensor-tip guidewires: A new methodologic approach for assessment of coronary hemodynamics before and after coronary interventions (original) (raw)

1993, The American Journal of Cardiology

The use of miniaturized pressure and veto&y sensors mounted on angkplastyguklewires altows the simultaneous measurement of coronary Mood flow veloctty and transstenotk pressure gradii, 2 parameters that, combined, should perfectly characterize stenosis hemodynamks. 7he aim of thii artkk is assessment of the changes in coronary blood flow velocity observed wtth a Doppler-tipped an@oplasty guhtewire in 35 patients undergoing balloon angkptasty. We atso report our inttlal experience in 16 patients with the comMned use of sensor-tip pressure and Doppler guhlewires, and we discuss the applica-Uon of new methodokgk approaches for the study of the coronary circulation allowed by these techniques, such as the instantaneous assessment of the flow velocity/pressure and pressure gradient/flow vekctty relations. Before and after angkptasty, flow vekctty measurements were obtained distal to the stenosis, both k baseline condDions and after intracoronary injection of 8-12.5 mg of papaverke. The Doppler guidewire was left in place during the dilation procedure and the Doppler stgnal was continuously recorded during balloon inflation and after deflation to monitor the development of collateral flow, the restoration of flow after balloon deflation, the phase of postoccksive reacttve hyperemia, and, incidently, the devekpment of flowlimtting complkations. Merits and pitfalls of several flow velocity parameters (average peak velocity, coronary flow velocity reserve, diastolk/systolk veloctty ratio), as well as of pa-rametersdertvedfromthecomMnatknofpressure and velocii measurements (transstenotk pressure gradient/flow velocity relatkn and Instantaneous diastotk hyperemk flow velocDy/ pressure relatiin) were evaluated in 35 patients wtth, and 37 wtthout, stgnifkant coronary stenoses. Miniaturlzatii offlowveloctty and pressure sensors has made these v approaches applicable in the hrtewentknal suite, yiek6ng reproducible and accurate a88888menf8 of parameters previously measured onty in experimental animal models.