Physiological sensor delivery device and method
An intravascular sensor delivery device for measuring a physiological parameter of a patient, such as blood pressure, within a vascular structure or passage. In some embodiments, the device can be used to measure the pressure gradient across a stenotic lesion or heart valve. The sensor delivery device can be sized to pass over different sizes of guidewires to enable usage in coronary and peripheral arteries, for example.
1. A method comprising:
inserting a guidewire into the anatomical structure of a patient;
sliding a sensor delivery device over the guidewire to a location of interest within an anatomical structure of the patient, wherein the location of interest comprises a stenotic lesion, and the sensor delivery device includes a first sensor configured to measure a physiological parameter of the patient,
measuring, with the first sensor, the physiological parameter of the patient on a first side of the stenotic lesion during a diastolic phase of at least one cardiac cycle,
measuring, with a second sensor, the physiological parameter of the patient on a second side of the stenotic lesion during the diastolic phase of at least one cardiac cycle,
calculating a numerical value based on the physiological parameter measured by the first sensor and the physiological parameter measured by the second sensor; and
providing the numerical value to evaluate the anatomical structure.
2. The method of claim 1 , wherein the numerical value is based on a ratio of the physiological parameters measured by the first and second sensors.
3. The method of claim 2 , wherein:
the first side is a downstream side of the stenotic lesion, and measuring the physiological parameter of the patient on the first side comprises providing a measured physiological parameter P d ,
the second side is an upstream side of the stenotic lesion, and measuring the physiological parameter of the patient on the second side comprises providing a measured physiological parameter P p , and
the ratio is P d /P p .
4. The method of claim 1 , wherein the numerical value is based on a difference between the physiological parameters measured by the first and second sensors.
5. The method of claim 1 , wherein the physiological parameter measured by the first and second sensors is pressure.
6. The method of claim 5 , wherein the pressure measured by at least one of the first and second sensors is an average value.
7. The method of claim 6 , wherein the average value is determined based upon a single pressure measurement obtained during the diastolic phase of each of a number of successive cardiac cycles.
8. The method of claim 7 , wherein the successive cardiac cycles consists of at least two consecutive cardiac cycles.
9. The method of claim 6 , wherein the average value is determined based upon multiple pressure measurements obtained during the diastolic phase of each of a number of successive cardiac cycles.
10. The method of claim 1 , wherein measuring the physiological parameter of the patient with the second sensor comprises measuring the physiological parameter of the patient with the second sensor substantially simultaneously with measuring of the physiological parameter of the patient with the first sensor.
11. The method of claim 1 , wherein the first sensor comprises a pressure transducer.
12. The method of claim 1 , wherein the sensor delivery device comprises the second sensor.
13. The method of claim 1 , wherein the second sensor comprises a pressure transducer located outside of the patient that is in fluid communication with a fluid tubing that provides fluid communication between the pressure transducer and the patient.
14. The method of claim 1 , wherein inserting the guidewire into the anatomical structure comprises inserting the guidewire across the stenotic lesion within a vascular structure of the patient.
15. The method of claim 1 , wherein inserting the guidewire into the anatomical structure of the patient comprises inserting the guidewire into one of an artery of the patient and across a heart valve of the patient.
16. The method of claim 1 , further inserting an interventional therapy device over the guidewire and deploying the interventional therapy device at the location of interest within the anatomical structure of the patient.
17. The method of claim 16 , wherein the interventional therapy device is a stent.
18. The method of claim 16 , further comprising withdrawing an interventional therapy delivery device from the guidewire prior to sliding the sensor delivery device over the guidewire.
19. The method of claim 16 , further comprising inserting a catheter into the patient, wherein inserting the interventional therapy device over the guidewire and sliding the sensor delivery device over the guidewire comprises advancing the interventional therapy device and the sensor delivery device through the catheter.
20. The method of claim 1 , wherein providing the numerical value to evaluate the anatomical structure comprises displaying the numerical value on a computer display.