Related Experiment Videos
Continuous coronary flow velocity monitoring during coronary interventions: velocity trend patterns associated with
M J Kern1, F V Aguirre, T J Donohue
1Department of Internal Medicine, St. Louis University Hospital, MO 63110.
Insights
Continuous Doppler monitoring of coronary blood flow velocity offers early detection of flow instability during interventional procedures. This method can predict adverse events like abrupt vessel closure before angiography.
Area of Science:
- Cardiology
- Interventional Cardiology
- Biomedical Engineering
Background:
- Coronary flow instability during interventions can lead to adverse events.
- Early detection of such instability is crucial for patient outcomes.
- Current methods like angiography may not provide continuous monitoring.
Purpose of the Study:
- To evaluate the utility of continuous blood flow velocity monitoring using a Doppler-tipped guide wire.
- To assess the potential for early warning of coronary flow instability and adverse events.
- To correlate flow patterns with procedural outcomes.
Main Methods:
- Utilized a 0.018-inch Doppler-tipped angioplasty guide wire for continuous monitoring.
- Monitored blood flow velocity in 32 patients post-coronary procedures (angiography, atherectomy, stenting, thrombolysis, AMI).
- Recorded flow trends for an average of 19 minutes post-procedure.
Main Results:
- Seven patients experienced flow-related events during monitoring, including vasospasm, flow cessation, and cyclical variations.
- Cyclical flow variations and rapid velocity decline correlated with abrupt vessel closure.
- Continuous monitoring identified patterns indicative of unstable flow before angiography.
Conclusions:
- Continuous Doppler flow velocity monitoring is easily integrated into interventional procedures.
- This technique provides an early warning of unstable coronary flow.
- It has the potential to predict abrupt vessel closure and other adverse events.
Abstract:
Continuous measurement of blood flow velocity during interventional procedures has the potential to provide an early warning of coronary flow instability, which can lead to abrupt closure or other adverse events before angiography. The magnitude and fluctuations of the average velocity over time (trend) was studied by using a 0.018-inch Doppler-tipped angioplasty guide wire in 32 patients after coronary angiography (n = 20), atherectomy (n = 2), urgent stent (n = 6), urgent vein graft thrombolysis (n = 4), or acute myocardial infarction (n = 2). The patients (mean age 60 +/- 11 years) had postprocedural in-laboratory flow monitoring for a mean of 19 +/- 11 (range 8 to 36) minutes. The coronary artery monitored was the left anterior descending in 13, circumflex in 6, right coronary artery in 9, and saphenous vein graft in 4. Seven patients had flow-related events during continuous flow velocity monitoring before serial angiographic study. These events included coronary vasospasm (abrupt flow acceleration), vasovagal flow cessation, cyclical flow variations resulting from accumulation of intraluminal thrombus, and rapid decline of flow velocity. The last two patterns were associated with abrupt vessel closure during angioplasty. Continuous flow velocity monitoring is easily incorporated into routine interventional procedures and provides an early indication of unstable flow and the potential for abrupt vessel closure and other adverse events.