1. A method for use with an implantable system, comprising:
(a) obtaining one or more electrogram (EGM) signal(s) indicative of cardiac electrical activity;
(b) performing dominant frequency (DF) analysis of at least one of the EGM signal(s), wherein DF analysis comprises determining the DF of at least one of the EGM signal(s) in the frequency domain, wherein the DF is the frequency component of the EGM signal in the frequency domain having the greatest amplitude; and
(c) using results of the DF analysis to determine whether to deliver anti-tachycardia pacing (ATP) to attempt to terminate a tachycardia, or whether to deliver a shock to attempt to terminate the tachycardia without first delivering ATP.
2. The method of claim 1, wherein steps (b) and (c) are performed in response to a tachycardia being detected using an analysis other than DF analysis.
3. The method of claim 1, wherein:
the DF analysis performed at step (b) results in a tachycardia being characterized as stable or unstable; and
step (c) comprises determining that ATP is to be delivered if the tachycardia was characterized as stable, and determining that a shock is to be delivered without first delivering ATP if the tachycardia is characterized as unstable.
4. The method of claim 1, wherein:
the results of step (b) include a detected DF; and
step (c) comprises
(c.1) comparing the detected DF to a threshold;
(c.2) determining that ATP will be delivered to attempt to terminate the tachycardia, if the detected DF is below the threshold; and
(c.3) determining that a shock will be delivered to attempt to terminate the tachycardia, without first delivering ATP, if the detected DF is above the threshold.
5. An implantable cardiac device comprising:
one or more pulse generator configured to deliver pacing therapy;
one or more sensing circuit configured to obtain one or more electrogram (EGM) signal(s) indicative of cardiac electrical activity;
one or more shocking circuit configured to deliver a shock;
a dominant frequency (DF) analysis module configured to
perform DF analysis of at least one of the EGM signal(s), wherein the DF analysis comprises at least analyzing each of the at least one of the EGM signal(s) in the frequency domain to determine the frequency component having the greatest amplitude for each EGM signal; and
determine whether to deliver anti-tachycardia pacing (ATP) to attempt to terminate a tachycardia, or whether to deliver a shock to attempt to terminate the tachycardia without first delivering ATP based on the DF analysis.
6. The implantable cardiac device of claim 5, wherein:
the results of the DF analysis include a detected DF; and
the DF analysis module is also configured to
compare the detected DF to a threshold;
determine that ATP will be delivered to attempt to terminate the tachycardia, if the detected DF is below the threshold; and
determine that a shock will be delivered to attempt to terminate the tachycardia, without first delivering ATP, if the detected DF is above the threshold.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. A method for preparing stable oligosaccharides from a glycoprotein having linked oligosaccharides, said method comprising the steps o
contacting said glycoprotein with an aqueous solution of ammonium hydroxide and ammonium carbonate for a period of time sufficient to cleave linked oligosaccharides from the glycoprotein to form oligosaccharide products and a protein by-product;
separating the oligosaccharide products from the ammonium hydroxide and the ammonium carbonate; and
separating at least a portion of the oligosaccharide products from the protein by-product.
2. The method of claim 1 further comprising the step of contacting the oligosaccharide products with an aqueous acid.
3. The method of claim 2 wherein the acid is boric acid.
4. The method of claim 2 further comprising the step of separating the oligosaccharide products from the acid.
5. The method of claim 3 further comprising the step of separating the oligosaccharide products from the acid.
6. The method of claim 1 further comprising the step of separating at least one oligosaccharide products from other oligosaccharide products.
7. The method of claim 2 further comprising the step of separating at least one oligosaccharide products from other oligosaccharide products.
8. The method of claim 3 further comprising the step of separating at least one oligosaccharide products from other oligosaccharide products.
9. The method of claim 4 further comprising the step of separating at least one oligosaccharide products from other oligosaccharide products.
10. The method of claim 5 further comprising the step of separating at least one oligosaccharide products from other oligosaccharide products.
11. The method of claim 1 further comprising the step of reacting the separated oligosaccharide products with a labeling agent to form a mixture of oligosaccharide derivatives having a common covalently bound label.
12. The method of claim 2 further comprising the step of reacting the separated oligosaccharide products with a labeling agent to form a mixture of oligosaccharide derivatives having a common covalently bound label.
13. The method of claim 3 further comprising the step of reacting the separated oligosaccharide products oligosaccharides with a labeling agent to form a mixture of oligosaccharide derivatives having a common covalently bound label.
14. The method of claim 4 further comprising the step of reacting the separated oligosaccharide products with a labeling agent to form a mixture of oligosaccharide derivatives having a common covalently bound label.
15. The method of claim 5 further comprising the step of reacting the separated oligosaccharide products oligosaccharides with a labeling agent to form a mixture of oligosaccharide derivatives having a common covalently bound label.
16. The method of claim 11 further comprising the step of separating at least one labeled oligosaccharide derivative from other labeled oligosaccharide derivatives.
17. The method of claim 12 further comprising the step of separating at least one labeled oligosaccharide derivative from other labeled oligosaccharide derivatives.
18. The method of claim 13 further comprising the step of separating at least one labeled oligosaccharide derivative from other labeled oligosaccharide derivatives.
19. The method of claim 14 further comprising the step of separating at least one labeled oligosaccharide derivative from other labeled oligosaccharide derivatives.
20. The method of claim 15 further comprising the step of separating at least one labeled oligosaccharide derivative from other labeled oligosaccharide derivatives.
21. A method for preparing stable reducing oligosaccharides by cleavage of a glycoprotein having linked oligosaccharides, said method comprising the steps of
contacting the glycoprotein with an aqueous solution of ammonium hydroxide and ammonium carbonate to cleave the linked glycans and from intermediate product oligosaccharide products and cleaved protein by-products;
separating the intermediate products from the aqueous ammonium hydroxide and ammonium carbonate;
reacting the intermediate oligosaccharide products with aqueous boric acid to form reducing oligosaccharide products; and
separating at least a portion of the reducing oligosaccharide products from the aqueous boric acid and the protein by-products.
22. The method of claim 21 wherein the step of separating the aqueous ammonium hydroxide and ammonium carbonate from the intermediate oligosaccharide products is carried out by evaporation of aqueous solutions of the products and those reagents.
23. The method of claim 21 wherein the reducing oligosaccharide products are separated from the boric acid by evaporation of methanol solutions of the product mixture.
24. The method of claim 21 further comprising the step of separating at least one reducing oligosaccharide product from the other reducing oligosaccharide products.