微循环阻力指数(IMR)的临床价值

IMR的测量(通过温度稀释法测量) 操作方法
血流
冠脉
压力导丝感受器
导引导管
Transit mean time / Tmn
1.静息时弹丸式注射 2.最大充血状态下弹丸式注射
图示
注射器
Tmn hyp Tmn rest
IMR的推导
微循环阻力 = ∆ P压力 / Flow血流 (简单)
Pd远端压力 血流
Pv 静脉压力~ 0
微循环阻力
∆ Pressure = Pd - Pv = Pd (Pv = 0)
Flow 1 / Tmn IMR = Pd / (1 / Tmn) IMR = Pd x Tmn
(最大充血状态下)
IMR的测量
IMR = = =
ANbP83no39dormxxrm0aHa.ly3IlpM7IMeRrRe<m>2ic350Tmn
(压力, 生理盐水和造影剂) • 用带 safety reservoir注射器
压力导丝传感器 定位
• 把压力导丝传感器放到冠脉远端 (离导引导管开口>5 cm).
如果距离太近，测量的 Tmn会太短 (特别是最大充 血状态下).
• 在测量中保持传感器在同一位置 (给充血药物前和给药中).
如果传感器位置变化，对结果会有影响.建议在导引导 管放到冠脉远端、基础状态注射结束和充血状态注射 结束三个时间点踩X线留图比较传感器位置是否变化
手术步骤
3.
手工计算
IMR = = =
ANbP83no39dormxxrm0aHa.ly3IlpM7IMeRrRe<m>2ic350Tmn
错误信息
温度下降小
于–1℃
注射时间长 于 0.6 秒.
温度恢复正 常的时间超 过8秒
Tmn 小于 0,1 秒。 把 传感器放到 更远的位置。
和错误信息 同时出现
正常血管的阻力
冠脉阻力
Arterioles
Epicardial Vessel
Capillaries Venules
Kaul and Jayaweera Eur Heart J 2006;27:2272-74.
FFR, (CFR) IMR: the Coronary Circulation Full Picture
Hyperemia
长效的充血药物!!!
Precautions for IMR measurement
Hyperemia • Use long-lasting hyperemic stimuli to attain constant hyperemia during the measurements. • If possible, verify maximum hyperemic effect (by using Pd/Pa quota) or IMR will be incorrect.
The decrease in sensor shaft temperature was not fast or deep enough to trigger the instruments recording function. Solution
• Short and distinct saline injection. Use ”one-shot” (3-5 cc) syringe for a better punch.
Cause: The shaft temperature didn't reach its minimum value fast enough. This means that the
injection time, defined as the time between start of injection and the minimum shaft temperature, was too long (>0.6 seconds).
血压，心率和心肌收缩力改变后，CFR 改变远大于IMR
Correlation with Baseline
1.0
P<0.05
0.8
0.6
0.4
ቤተ መጻሕፍቲ ባይዱ
0.2
0.0 IMR
CFR
FFR
Ng et al. Circulation 2006;113:2054-61.
准备和手术步骤
准备
• 使用6F guiding • 三联三通
4. Error messages
• A saline injection must pass certain criteria's to be accepted as an valid injection. If the injection does not pass all criteria's an injection error will occur.
2.
基线测量
注射器抽3ml生理盐水 按 REC 键开始记录, 按照屏幕提示. 快速稳定的注射生理盐水
重复3次
手术步骤
3.
最大充血状态测量
通过药物达到并保持最大充血状态
按Rec键开始记录 ，按照屏幕提示快速稳定的注射3次生 理盐水
View FFR and IMR
When all measurements have been done press STOP/VIEW on the remote control to save the recording and view the recorded pressure and dilution curves together with the FFR value. The value of IMR has to be calculated: IMR = Pd x Tmnhyp (88 x 0.50 = 40)
Abnormal Microcirculation
Circulation 2003;107:3129-3132
IMR is independent of epicardia stenosis?
Animal Validation
Circulation 2004;109:2269-2272
IMR的重复性
Pressure
FFR
Temperature
• Thermodilution
• (Temperature of the plaque)
(CFR) IMR ABF
State-of-the-art PressureWire 5 and Certus, flow and temperature.
Pressure transducer
Precautions for IMR measurement
Catheter positioning • Avoid unstable position or the temperature signal may fluctuate. • Avoid “spilling” saline, position the catheter in ostium or the temperature signal may fluctuate. • Avoid deep engagement or the flow may be reduced.
PressureWire® Sensor positioning • Position transducer >7 cm from opening of guiding catheter or inaccurate CFR/Tmn (Transit mean time) values might occur. The Tmn value may become to short and will be rejected by the software
The instrument indicates ”Inject Now”, the physician injects saline and the shaft and sensor temperature decreases, but the instrument doesn't respond at all. Cause
• The injection was too slow, keeping the shaft temperature low for too long.
• The injection of saline was uneven, causing a ”bumpy” shaft signal and a late minima.
• An injection error can be caused by a number of reasons and an error message displayed in the instruction window contains information on what caused the problem.
2023最新整理收集 do something
微循环阻力指数（IMR）的临床价值
一.IMR的测量方法 二.IMR的临床价值
IMR
MACRO vascular
Compartment
MICRO vascular
Compartment
FFR CFR (and Non-Invasive Testing)
• Even and steady injection-movement
• Less injection volume (3-5 cc)
1 0 -1 -2 -3 -4 -5 -6
Injection errors
5. ”Tmn value too low” message Indication: After injection the sign ”Tmn value too low” is displayed Cause: The calculated Tmn value was less than 0.1 seconds
• The sensor tip is placed too close to the catheter opening Solution
• Adjust sensor and catheter positions
1 0 -1 -2 -3 -4 -5 -6
IMR的确立
破坏微循环后IMR的改变
• Increase saline volume (3-5 cc).
• Colder saline (room temperature, ~20ºC).
1 0 -1 -2 -3 -4 -5 -6
Injection errors
2. ”Slow Injection” message
Indication: After injection the sign ”Slow Injection” is displayed
• When an error message is flashing an INJECT AGAIN message is also displayed, prompting a new injection.
5. Injection errors
1. The Instrument does not respond to the injection Indication
校准 PressureWire® ，进入 CFR 模式
4. The CFR screen layout
手术步骤
1.
注射器抽3ml生理盐水（室温）
通过导引导管注射，检查温度是否能够最少下降2℃。
手术步骤
1.
注射器抽3ml生理盐水（室温）
通过导引导管注射，检查温度是否能够最少下降2℃。
手术步骤
• The injected amount of saline was too large, keeping the shaft temperature low too long.
Solution:
• Short and distinct saline injection. Use ”one-shot” (3-5 cc) syringe for a better punch.
IMR的确立
动物模型
Guide
Radio-opaque Occluder
Pressure Wire
LAD Flow Probe
Circulation 2003;107:3129-3132.
IMR的确立
破坏微循环后IMR的改变
IMR
30
p = 0.002
25
20
15
10
5
0
Normal Microcirculation