SYSTEMS AND METHODS FOR IMPLEMENTING HEART GEOMETRICAL MEASUREMENTS

• US 20090099563A1
• Filed: 06/23/2008
• Published: 04/16/2009
• Est. Priority Date: 06/21/2007
• Status: Active Grant

• Current Assignee: Trustees Of Columbia University In The City Of New York (Columbia University)
• Original Assignee: Trustees Of Columbia University In The City Of New York (Columbia University)
• Inventors: Ciaccio, Edward J.
• Granted Patent: US 8,386,014 B2
• Time in Patent Office: Days
• US Class Current: 606/41
• CPC Class Codes: A61B 18/1492 having a flexible, catheter-like structure, e.g. for heart ablation A61B18/1477 takes precedence
• CPC Class Codes: A61B 2018/00839 Bioelectrical parameters, e.g. ECG, EEG
• CPC Class Codes: A61B 2034/107 Visualisation of planned trajectories or target regions
• CPC Class Codes: A61B 2090/061 for measuring dimensions, e.g. length
• CPC Class Codes: A61B 2090/374 NMR or MRI
• CPC Class Codes: A61B 34/25 User interfaces for surgical systems
• CPC Class Codes: A61B 5/1075 for measuring dimensions by non-invasive methods, e.g. for determining thickness of tissue layer A61B8/0858 takes precedence
• CPC Class Codes: A61B 90/36 Image-producing devices or illumination devices not otherwise provided for
• CPC Class Codes: G06T 2207/10088 Magnetic resonance imaging [MRI]
• CPC Class Codes: G06T 2207/30048 Heart; Cardiac
• CPC Class Codes: G06T 7/0012 Biomedical image inspection
• CPC Class Codes: G06T 7/62 of area, perimeter, diameter or volume

Abstract

In some embodiments, the disclosed subject matter provides a method of identifying the source of arrhythmia, e.g. reentrant ventricular tachycardia, in a patient. In other embodiments, the disclosed subject matter provides a method for treating or preventing reentrant ventricular tachycardia in a patient. In still other embodiments, the disclosed subject matter provides systems for identifying the location of a candidate ablation site in a patient. In some embodiments, the patient has suffered from a myocardial infarction or has undergone structural remodeling of the heart caused by, e.g., cardiac fibrosis or the presence of dense trebeculation, resulting in nonviable areas with border zones (BZ).

Claims

1. A method of identifying the source of reentrant ventricular tachycardia in a patient, said method comprising:

a) obtaining one or more images of the region of the patient'"'"'s heart;

b) identifying a border zone (BZ);

c) calculating the thickness of the BZ;

d) constructing a three-dimensional thickness map by measuring the thickness of said border zone at multiple points so that a sufficient spatial resolution is obtained, and determining a local spatial gradient (Δ

T) of said thickness over two or more locations in said BZ; and

e) using said thickness and Δ

T to determine the reentry isthmus location and one or more candidate ablation sites.

2. The method of claim 1, wherein the thickness is calculated as the straight line distance between an infarct or other structurally remodeled surface to the heart surface.

3. The method of claim 1, wherein the thickness is calculated as the straight line distance between edges of the infarct or other structurally remodeled surface when that surface is three-dimensional.

4. The method of claim 1, further comprising performing ablation of said one or more candidate ablation sites.

5. The method of claim 1, wherein said patient has suffered from a myocardial infarction.

6. The method of claim 1, wherein said patient has undergone structural remodeling of the heart.

7. The method of claim 6, wherein said structural remodeling is caused by cardiac fibrosis or the presence of dense trebeculation.

8. The method of claim 1, wherein said obtaining images comprises the use of imaging technology capable of achieving 1 mm resolution or less.

9. The method of claim 8, wherein said imaging technology is magnetic resonance imaging (MRI).

10. A method for treating, preventing, and/or inhibiting postinfarction reentrant ventricular tachycardia in a patient, said method comprising:

a) obtaining one or more images of the patient'"'"'s heart;

b) identifying a border zone (BZ);

c) calculating the thickness of the BZ;

d) constructing a three-dimensional thickness map by measuring the thickness of said border zone at multiple points so that a sufficient spatial resolution is obtained, and determining a local spatial gradient (Δ

T) of said thickness over two or more locations in said BZ;

e) using said thickness and Δ

T to determine the reentry isthmus location and one or more candidate ablation sites; and

f) performing ablation of said one or more candidate ablation sites.

11. The method of claim 10, wherein the thickness is calculated as the straight line distance between an infarct or other structurally remodeled surface to the heart surface.

12. The method of claim 10, wherein the thickness is calculated as the straight line distance between edges of the infarct or other structurally remodeled surface when that surface is three-dimensional.

13. The method of claim 10, wherein said patient has suffered from a myocardial infarction.

14. The method of claim 10, wherein said patient has undergone structural remodeling of the heart.

15. The method of claim 14, wherein said structural remodeling is caused by cardiac fibrosis or the presence of dense trebeculation.

16. The method of claim 10, wherein said obtaining images comprises the use of imaging technology capable of achieving 1 mm resolution or less.

17. The method of claim 16, wherein said imaging technology is magnetic resonance imaging (MRI).

18. A system for identifying the location of a candidate ablation site in a patient, the system comprising:

a) a processor, image acquisition means for obtaining images of a patient'"'"'s heart operatively coupled to the processor, and a memory operatively coupled to the processor, the memory storing program instructions that when executed by the processor, cause said processor to utilize said image acquisition means for obtaining images to;

obtain images of a patient'"'"'s heart;

display each image on a screen;

measure a thickness of a border zone;

determine a local spatial gradient (Δ

T) of said thickness over two or more locations in said border zones;

plot said thickness and thickness gradient values on three-dimensional maps; and

locate estimated positions of reentrant circuits and actual conduction block during reentrant ventricular tachycardia.

19. The system of claim 18, wherein said system further comprises analyzing means, which analyzing means operatively coupled with said image acquisition means for analyzing whether the geometry and location of reentrant circuits indicate predisposition to ventricular tachycardia in the patient.

20. The system of claim 18, wherein said patient has undergone structural remodeling of the heart.