Device and method for diagnosis of cardiac tamponade

Abstract

The invention relates to a system for challenging the pericardial space, to provide an indication of the risk of cardiac tamponade in a patient, as well as methods for diagnosis of, and determination of the extent of, a tamponade, and treating a patient in whom there is a detected cardiac tamponade.

Claims

1. A method for diagnosing the presence of, or detecting the extent of, a cardiac tamponade in an individual, the method comprising: inflating a balloon located in the pericardial space, mediastinal space, behind the sternum, or behind the heart of a patient, to such an extent that one or both of a velocity or flow of blood through a left or right ventricular outflow tract changes, thereby providing an indication of any potential tamponade or the extent of any tamponade; measuring one or both of the velocity or flow of blood through the left or right ventricular outflow tract using a probe, wherein the probe is communicatively coupled to a processor, wherein the processor is configured for calculation of blood flow through the left or right ventricular outflow tract wherein the balloon is inflated to such an extent that the blood flow through the left or right ventricular outflow tract is affected, such that the system gives an indication of the extent of potential tamponade in the patient based on the relationship between the volume of inflation of the balloon and the blood flow through the left or right ventricular outflow tract.

2. A method for treating cardiac tamponade the method comprising: determining a space available within any of a pericardial space, a mediastinal space, behind a sternum, or behind a heart of a patient by inflating a balloon located in the pericardial space, the mediastinal space, behind the sternum, or behind the heart, respectively, to such an extent that one or both of a velocity or flow of blood through a left or right ventricular outflow tract changes, thereby providing an indication of any potential tamponade; removing all or part of any obstruction within the pericardial space, the mediastinal space, behind the sternum, or behind the heart in the event that the inflation of the balloon is consistent with cardiac tamponade being detected; inflating a balloon located in the pericardial space, mediastinal space, behind the sternum, or behind the heart; and measuring one or both of the velocity or flow of blood through the left or right ventricular outflow tract using a probe, wherein the probe is communicatively coupled to a processor, wherein the processor is configured for calculation of blood flow through the left or right ventricular outflow tract wherein the balloon is inflated to such an extent that the blood flow through the left or right ventricular outflow tract is affected, such that the system gives an indication of the extent of potential tamponade in the patient based on the relationship between the volume of inflation of the balloon and the blood flow through the left or right ventricular outflow tract; and treating cardiac tamponade in patients diagnosed with cardiac tamponade.

3. The method of claim 1, wherein the velocity or flow of blood is measured by a probe that is communicatively coupled to a processing device, the processing device configured for calculation of blood flow through the left or right ventricular outflow tract.

4. The method of claim 3, wherein the probe is a Doppler probe capable of measuring the Doppler signal en face of the right ventricular outflow tract, for measurement of blood velocity.

5. The method of claim 1, wherein the balloon is a pressure-sensing balloon.

6. The method of claim 1, wherein the balloon is configured to provide even pressure over the heart when inflated.

7. The method of claim 1, wherein the balloon is configured to occupy some of the pericardial space, mediastinal space, the space behind the sternum, or the space behind the heart when inflated, limiting space for the heart and thus challenging the space available to the heart to relax and therefore determine whether the heart is at risk of developing tamponade.

8. The method of claim 3, wherein one or more housing compartment for the probe and/or balloon facilitate removal or insertion of the balloon into the chest, by providing a delivery pathway into the chest.

9. The method of claim 3, wherein the processing device is additionally configured to monitor the pressure sensed by the balloon and the volume of fluid injected into the balloon.

10. The method of claim 1, wherein the diameter of the left or right ventricular outflow tract is used to calculate flow from the measured blood velocity.

11. The method of claim 9, wherein the processing device is additionally configured to generate a pressure-volume curve over time.

12. The method of claim 2, wherein the probe is a Doppler probe capable of measuring the Doppler signal en face of the right ventricular outflow tract, for measurement of blood velocity.

13. The method of claim 2, wherein the balloon is a pressure-sensing balloon.

14. The method of claim 2, wherein the balloon is configured to provide even pressure over the heart when inflated.

15. The method of claim 2, wherein the balloon is configured to occupy some of the pericardial space, mediastinal space, the space behind the sternum, or the space behind the heart when inflated, limiting space for the heart and thus challenging the space available to the heart to relax and therefore determine whether the heart is at risk of developing tamponade.

16. The method of claim 2, one or more housing compartments facilitate removal or insertion of the balloon into the chest, by providing a delivery pathway into the chest.

17. The method of claim 2, wherein the processor is additionally configured to monitor the pressure sensed by the balloon and the volume of fluid injected into the balloon.

18. The method of claim 2, wherein a diameter of the left or right ventricular outflow tract is used to calculate flow from the measured blood velocity.

19. The method of claim 2, wherein the processing device is further communicatively coupled to the balloon.

Description

(1) The invention is illustrated in the attached figures, in which

(2) FIG. 1 shows the heart contained within the pericardial sac, with arrows demonstrating the pressure exerted on the heart during tamponade

(3) FIG. 2 also shows the heart contained within the pericardial sac. Compression of the heart following blood collection within the sac can be seen.

(4) FIG. 3 is a diagram of one embodiment of the present invention. A balloon is inserted into the pericardial sac and injected with fluid, whilst a Doppler probe is suitably placed to monitor left or right ventricular outflow.

(5) FIG. 4 is a diagram of the heart with major vessels labelled. The two preferred positions of the Doppler probe are indicated (on the aorta or on the pulmonary artery bifurcation).

(6) Preferred statements of the invention include:

(7) 1 A system for assessing the extent of cardiac tamponade in a patient, comprising:

(8) A Doppler probe capable of detecting velocity and/or flow of blood in either the left or right ventricular outflow tract; a balloon suitable for insertion and inflation in the pericardial space, mediastinal space, behind the sternum, or behind the heart; and a processing device communicatively coupled to the probe and optionally also the balloon
wherein the processing device is configured for determination of blood flow through the left or right ventricular outflow tract, such that the system gives an indication of the extent of potential tamponade in the patient based on the relationship between the volume of inflation of the pericardial balloon and the blood flow through the left or right outflow tract.
2 The system of statement 1 wherein the balloon is a pressure-sensing balloon.
3 The system of any of statements 1-2 wherein the balloon is configured to provide even pressure over the heart when inflated.
4 The system of any of statements 1-3 wherein the balloon is configured to occupy some of the pericardial space, mediastinal space, the space behind the sternum, or the space behind the heart when inflated, limiting space for the heart and thus challenging the space available to the heart to relax and therefore determine whether the heart is at risk of developing tamponade.
5 The system of any of statements 1-4 further comprising housing compartment(s) for the probe and/or balloon, wherein said housing compartment(s) facilitate removal and/or insertion of the balloon into the chest, by providing a delivery pathway into the chest.
6 The system of statement 2 wherein the processing device is additionally configured to monitor the pressure sensed by the balloon and the volume of fluid injected into the balloon, and optionally to generate a pressure-volume curve over time.
7 The system of any preceding statements wherein the diameter of the left or right ventricular outflow tract is used to calculate flow from the measured blood velocity.
8 A balloon suitable for placement in the pericardial space, mediastinal space, behind the sternum, or behind the heart, configured to provide even pressure across the heart when inflated, and with a volume variable from 10 ml to 250 ml.
9 A method for detecting cardiac tamponade comprising
(1) inflating a balloon located in the pericardial space, mediastinal space, behind the sternum, or behind the heart;
(2) measuring the velocity and/or flow of blood through the left or right ventricular outflow tract, suitably using a Doppler probe, wherein the probe is communicatively coupled to a processor,
(3) wherein the processor is configured for calculation of blood flow through the left or right ventricular outflow tract such that the system gives an indication of the extent of potential tamponade in the patient based on the relationship between the volume of inflation of the balloon and the blood flow through the left or right ventricular outflow tract.

(9) A method for diagnosing cardiac tamponade comprising

(10) (1) inflating a balloon located in the pericardial space, mediastinal space, behind the sternum, or behind the heart;

(11) (2) measuring the velocity and/or flow of blood through the left or right ventricular outflow tract, suitably using a Doppler probe, wherein the probe is communicatively coupled to a processor,

(12) (3) wherein the processor is configured for calculation of blood flow through the left or right ventricular outflow tract such that the system gives an indication of the extent of potential tamponade in the patient based on the relationship between the volume of inflation of the balloon and the blood flow through the left or right ventricular outflow tract; and optionally treating cardiac tamponade in patients diagnosed with cardiac tamponade.