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 sensor delivery device within an anatomical structure of a patient, wherein the sensor delivery device comprises first, second, and third sensors configured to measure a physiological parameter of the patient, wherein the first and second sensors are located a first fixed distance apart on the sensor delivery device, wherein the second and third sensors are located a second fixed distance apart on the sensor delivery device, and wherein the first fixed distance is different from the second fixed distance,
positioning two sensors selected from the first, second, and third sensors respectively on a first side and a second side of a stenotic lesion in the anatomical structure so as to accommodate a length of the stenotic lesion between the two selected sensors, wherein all of the first, second, and third sensors are in proximity of the stenotic lesion;
measuring, with one of the selected two sensors, the physiological parameter of the patient on the first side of the stenotic lesion during a diastolic phase of at least one cardiac cycle,
measuring, with another one of the selected two sensors, the physiological parameter of the patient on the second side of the stenotic lesion during the diastolic phase of the at least one cardiac cycle,
calculating a numerical value based on the physiological parameters measured by the selected two sensors; 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 selected two 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 selected two sensors.
5 . The method of claim 1 , wherein the physiological parameters measured by the selected two sensors comprise respective pressures on the first and second sides of the stenotic lesion.
6 . The method of claim 5 , wherein the pressure measured by at least one of the selected two 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 comprises 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 inserting the sensor delivery device comprises inserting a guidewire into the anatomical structure of the patient.
11 . The method of claim 10 , wherein inserting the guidewire into the anatomical structure comprises inserting the guidewire across the stenotic lesion within a vascular structure of the patient.
12 . The method of claim 10 , 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.
13 . The method of claim 1 , wherein measuring the physiological parameter of the patient with the another one of the selected two sensors comprises measuring the physiological parameter of the patient with the another one of the selected two sensors substantially simultaneously with measuring of the physiological parameter of the patient with the one of the selected two sensors.
14 . The method of claim 1 , wherein the one of the selected two sensors comprises a pressure transducer.
15 . The method of claim 1 , wherein the another one of the selected two sensors comprises a pressure transducer.
16 . The method of claim 1 , further comprising inserting an interventional therapy device and deploying the interventional therapy device at the stenotic lesion.
17 . The method of claim 16 , wherein the interventional therapy device comprises a stent.
18 . The method of claim 16 , further comprising withdrawing the interventional therapy delivery device from the anatomical structure prior to positioning the sensor delivery device.
19 . The method of claim 1 , wherein providing the numerical value to evaluate the anatomical structure comprises displaying the numerical value on a computer display.