Ex Parte Blakley

Board of Patent Appeals and Interferences

Jan 12, 2009

10758813 (B.P.A.I. Jan. 12, 2009)

UNITED STATES PATENT AND TRADEMARK OFFICE
__________

BEFORE THE BOARD OF PATENT APPEALS
AND INTERFERENCES
__________

Ex parte DANIEL ROBERT BLAKLEY
__________

Appeal 2008-4553
Application 10/758,813
Technology Center 3700
__________

Decided: January 12, 2009
__________

Before DONALD E. ADAMS, RICHARD M. LEBOVITZ, and MELANIE
L. McCOLLUM, Administrative Patent Judges.

McCOLLUM, Administrative Patent Judge.

DECISION ON APPEAL
This is an appeal under 35 U.S.C. § 134 involving claims relating to
electocardial waveforms. The Examiner has rejected the claims as
anticipated or obvious. We have jurisdiction under 35 U.S.C. § 6(b). We
affirm-in-part.
Appeal 2008-4553
Application 10/758,813

2
STATEMENT OF THE CASE
“Typically, several electrodes are affixed to various chest locations on
the patient in order to record . . . electrocardial information. Further, at least
one reference electrode is placed at a location where electrical activity is
minimal, such as on one of the patient’s lower legs.” (Spec. 1.) Such a
reference electrode may “restrict[] the patient’s ability to walk or even wear
trousers without stressing the electrode and the skin at which the electrode is
attached” (id.).
The Specification discloses “a reference voltage-generating circuit
that supplants the reference electrode” (id. at 4). In particular, as depicted in
Figure 4, the Specification discloses “an electrode input 45 [that] conveys an
electrical voltage from one or more electrodes affixed to a patient’s chest”
(id.).
The signal from electrode input 45 is conveyed to event
detector 70. . . . [W]hen event detector 70 detects [a triggering
event], timing device 80 is placed in a waiting state until the
electrocardial waveform can be expected to enter an interval of
relative inactivity. . . . At the onset of [an expected interval of
relative inactivity], sample and hold device 85 samples the
value of the input electrocardial waveform. The sampled value
of the waveform is then held at the output of sample and hold
device 85 and conveyed to the inverting input of [an] amplifier.
The voltage sampled during the expected period of relative
inactivity can then be subtracted from electrode input 45
according to the well-known subtractive transfer function of the
summing amplifier of Figure 4.
(Id. at 4-5.)
As depicted in Figure 5, the Specification also discloses “a memory
and processor replacing the event detector, timing device, and sample and
hold device of Figure 4” (id. at 6). In particular, the Specification discloses
Appeal 2008-4553
Application 10/758,813

3
an “electrode input 45 [that] is input to memory 130 by way of analog to
digital converter 125” (id.).
[P]rocessor 140 searches for the various triggering events
within the electrocardial waveform stored in memory 130.
Upon the detection of an appropriate triggering event, . . .
processor 140 outputs a value to reference voltage
generator 145. Reference voltage generator 145 provides a
voltage to the inverting input of amplifier 95. Amplifier 95
then subtracts the reference voltage from the incoming signal.
(Id. at 7.)
Claims 1-32 are pending and on appeal. We will focus on claims 1,
10, 16, 22, and 27, each of which is an independent claim. The dependent
claims have not been argued separately and therefore each stand or fall
together with the independent claim from which it depends. 37 C.F.R.
§ 41.37(c)(1)(vii). Independent claims 1, 10, 16, 22, and 27 read as follows:
1. A method for applying a reference value to an electrocardial
waveform including a series of heart beats, the method comprising:
identifying a triggering event within the electrocardial waveform,
waiting a period of time after the triggering event for an interval of
relative inactivity in the waveform;
sampling the electrocardial wavefrom during the interval of relative
inactivity to provide a sample voltage value corresponding to a selected beat;
and
dynamically referencing the electrocardial waveform to the sample
voltage value over a period of the selected beat.
10. A system for generating a reference value of an electrocardial
waveform including a series of beats, comprising:
at least one electrode input that conveys a voltage signal of the
electrocardial waveform of a patient;
an event detector that detects an event within the electrocardial
wavefrom;
a sampling device that determines the reference value corresponding
to a selected beat;
Appeal 2008-4553
Application 10/758,813

4
a timing device that, after a wait period in response to the event
detector, activates the sampling device; and
a referencing element that applies the reference value to the voltage
signal over a period of the selected beat.
16. A device for recording an electrocardial waveform, comprising:
at least one input for receiving a signal from an electrode, the signal
representing an electrocardial waveform;
a sampling element to digitize the received signal;
a memory element coupled to the at least on input, that stores the
digitized signal;
a processor, coupled to the memory, and configured to:
identify a peak value of the received signal; and
determine a voltage value of the received signal during an
interval of relative inactivity, the interval located relative to the
peak value; and
a reference voltage generator for generating a voltage applied to the
incoming signal substantially equal to the determined voltage value.
22. A receiver for an electrocardial signal, comprising:
digital means for characterizing an electrocardial signal, the digital
means including:
a detector element for identifying at least one distinct feature of
the signal;
a sampling element to determine a value for an interval of the
signal; and
timing means to activate the sampling element after the feature
is detected and at the start of the sampled interval; and
analog means operably coupled to the digital means for modifying the
electrocardial signal, the analog means including;
a generator configured to output a voltage signal level as a
function of the interval value; and
an integrating element to integrate the electrocardial signal with
the generator signal.
27. A computer-readable media having computer-readable
instructions thereon, which, when executed by a computer, cause the
computer to execute a method for synthesizing a reference value for an
electrocardial waveform, the method comprising:
identifying a triggering event within the electrocardial waveform;
Appeal 2008-4553
Application 10/758,813

5
sampling the electrocardial waveform during an interval of relative
inactivity; and
referencing the electrocardial waveform to the sample;
wherein the triggering event includes a first and a second feature of
the electrocardial waveform.
Claims 1-15 and 27-32 stand rejected under 35 U.S.C. § 102(b) as
anticipated by Nearing (US Patent No. 6,169,919 B1, Jan. 2, 2001) (Ans. 3).
Claims 16-26 stand rejected under 35 U.S.C. § 103(a) as obvious over
Nearing in view of Ekstrom (US Patent No. 3,868,567, Feb. 25, 1975)
(Ans. 5).
ANTICIPATION
The Examiner finds that “Nearing discloses referencing an
electrocardial waveform, identifying a trigger, waiting for a period of
isoelectric activity, sampling the wave, and dynamically referencing the
voltage over a period of the selected beat that can utilize a computerized
system” (Ans. 3). In particular, the Examiner finds that “Nearing discloses
sampling an electrocardial waveform during a period of relative inactivity
(‘isoelectric’) that corresponds to a specific beat and creating a spline curve.
Nearing then references the electrocardial waveform to the sampled value
over a period of a selected beat.” (Id. at 6.) In addition, the Examiner finds
that “Nearing further discloses that this is done in real-time” (id.).
Issues
Has Appellant shown that the Examiner erred in concluding that
Nearing discloses: (a) “dynamically referencing the electrocardial
waveform to the sample voltage value over a period of the selected beat,” as
recited in claim 1; (b) “a referencing element that applies the reference value
to the voltage signal over a period of the selected beat,” as recited in
Appeal 2008-4553
Application 10/758,813

6
claim 10; and (c) “referencing the electrocardial waveform to the sample”
and a “triggering event includ[ing] a first and a second feature of the
electrocardial waveform,” as recited in claim 27?
Findings of Fact
1. Nearing discloses “a system and method for calculating a
magnitude of alternation in the T-waves of an electrocardiogram [ECG]
signal” (Nearing, col. 1, ll. 21-23).
2. Nearing discloses that preferably “a digitized ECG signal (i.e.,
ECG data) is received for processing” (Nearing, col. 1, ll. 51-52).
3. Nearing also discloses filtering the digitized ECG data (id. at
col. 4, ll. 51-53, & Figs. 3-4).
4. In particular, Nearing discloses “applying a baseline wander
removal filter to the ECG data to remove low frequency artifacts” (id. at
col. 1, ll. 59-62).
5. Nearing discloses:
The step of applying a baseline wander removal filter to the
ECG data includes determining an isoelectric value at each of a
first isoelectric point (point 1) in a first beat, a second
isoelectric point (point 2) in a second beat, and a third
isoelectric point (point 3) in a third beat of the ECG data; fitting
a spline curve to the first three isoelectric values; [and]
subtracting the values of the spline curve from the
corresponding values of the ECG data.
(Id. at col. 1, l. 66, to col. 2, l. 6.)
6. In discussing the baseline wander removal filter (step 504),
Nearing discloses that “the R-wave is generally used as a reference for
locating other portions of the beat complex because its large amplitude
permits it to be easily identified” (id. at col. 5, ll. 11-40).
Appeal 2008-4553
Application 10/758,813

7
7. Nearing also discloses that its method “may be implemented
using hardware, software or a combination thereof and may be implemented
in one or more computer systems or other processing systems” (id. at col. 9,
ll. 14-17).
Analysis
“A claim is anticipated only if each and every element as set forth in
the claim is found, either expressly or inherently described, in a single prior
art reference.” Verdegaal Bros., Inc. v. Union Oil Co., 814 F.2d 628, 631
(Fed. Cir. 1987).
With regard to claim 1, Appellant contends that “Nearing does not
disclose dynamic referencing of a voltage value over a period of a beat.
[Instead,] Nearing ‘...subtracts values of the spline curve from the
corresponding values of the ECG data...’ at multiple points in a beat of the
waveform.” (App. Br. 5.) We agree.
Claim 1 is directed to a method for applying a reference value to an
electrocardial waveform including a series of heart beats. The method
comprises “sampling the electrocardial waveform during [an] interval of
relative inactivity to provide a sample voltage value corresponding to a
selected beat; and dynamically referencing the electrocardial waveform to
the sample voltage value over a period of the selected beat.” We interpret
claim 1 to require that the waveform be referenced to the sample voltage
value over the period of an entire heart beat.
Nearing discloses “subtracting the values of the spline curve from the
corresponding values of the ECG data” (Finding of Fact (FF) 5). Nearing
does not disclose applying the isoelectric value to the ECG data over a
period of an entire heart beat. Instead, over the period of a heart beat,
Appeal 2008-4553
Application 10/758,813

8
Nearing references the waveform to spline curve values. Thus, we agree
with Appellant that the Examiner has not set forth a prima facie case that
Nearing discloses “referencing the electrocardial waveform to the sample
voltage value over a period of the selected beat,” as recited in claim 1.
With regard to claim 10, Appellant argues that Nearing “‘...subtracts
values of the spline curve from the corresponding values of the ECG data...’
at multiple points over a beat. This is different than applying a reference
voltage over a period of a beat.” (App. Br. 5-6.) We agree.
Claim 10 is directed to a system comprising “a sampling device that
determines [a] reference value corresponding to a selected beat; . . . and a
referencing element that applies the reference value to the voltage signal
over a period of the selected beat.” As discussed above, Nearing discloses
“subtracting the values of the spline curve from the corresponding values of
the ECG data” (FF 5). Nearing does not disclose applying the isoelectric
value to the ECG data over a period of an entire beat. Thus, we agree with
Appellant that the Examiner has not set forth a prima facie case that Nearing
discloses “a referencing element that applies the reference value to the
voltage signal over a period of the selected beat,” as recited in claim 10.
With regard to claim 27, Appellant argues that “the triggers cited by
the Examiner in Nearing refer to step 508 of Nearing’s method having to do
with eliminating noisy beats from the ECG data (see Fig. 5) and not to
Nearing’s method of removing noise from beats” (Reply Br. 7). We are not
persuaded. In discussing the baseline wander removal filter (step 504) for
removing noise from ECG data, Nearing discloses that “the R-wave is
generally used as a reference for locating other portions of the beat
complex” (FF 4 & 6).
Appeal 2008-4553
Application 10/758,813

9
Appellant also argues that “Nearing does not disclose the use of first
and second features as triggering events. Nearing only uses the apex of the
R-wave as a determining reference.” (App. Br. 6.) We are not persuaded.
As indicated by the Examiner, “claim 27 does not require multiple
triggers. . . . [T]he claim does not state that the first and second features are
used to trigger anything, just that the triggering event has a first and second
feature.” (Ans. 7-8.) In addition, we agree with the Examiner that, when the
triggering event is an R-wave, it inherently contains first and second features
(id. at 8).
In addition, Appellant argues “Nearing does not reference the
waveform to the sample data directly” (Reply Br. 7). We are not persuaded.
Although we agree with Appellant that Nearing does not disclose
referencing a waveform to the sample voltage value over the period of an
entire heart beat, we do not agree that Nearing does not directly reference
the waveform to the sample data at the isoelectric points.
Conclusion
The Examiner has not set forth a prima facie case that Nearing
discloses: (a) “dynamically referencing the electrocardial waveform to the
sample voltage value over a period of the selected beat,” as recited in
claim 1; or (b) “a referencing element that applies the reference value to the
voltage signal over a period of the selected beat,” as recited in claim 10. We
therefore reverse the anticipation rejection of claims 1 and 10 and of
claims 2-9 and 11-15, which depend from claim 1 or claim 10.
However, Appellant has not shown that the Examiner erred in
concluding that Nearing discloses “referencing the electrocardial waveform
to the sample” or “a triggering event includ[ing] a first and a second feature
Appeal 2008-4553
Application 10/758,813

10
of the electrocardial waveform,” as recited in claim 27. We therefore affirm
the anticipation rejection of claim 27. Claims 28-32 fall with claim 27.
OBVIOUSNESS
The Examiner relies on Nearing as discussed above and for disclosing
a digital system (Ans. 5). The Examiner relies on Ekstrom for disclosing “a
method and apparatus for analysis of an isoelectric value in an electrocardial
waveform, which includes a clock (48), analog sampler (52),
amplifier/generator (44) and a peak detector/trigger (42)” (id.). The
Examiner finds that the “system of Ekstrom samples an electrocardial
waveform, finds an isoelectric sample within the waveform for a reference
voltage, subtracts the reference voltage from the waveform using an
amplifier, and outputs the final waveform” (id.). In particular, the Examiner
finds that “Ekstrom teaches that it is known to use analog circuitry to detect
and measure an[] isoelectric area of a electrocardial signal” (id. at 5-6). The
Examiner concludes that it would have been obvious “to modify the digital
system for referencing electrocardial waveforms as taught by Nearing, with
[an] analog system as taught by Ekstrom” (id. at 6).
Issues
Has Appellant shown that the Examiner erred in concluding that it
would have been obvious to include, in the alternation quantification system
disclosed in Nearing, “a reference voltage generator for generating a voltage
applied to the incoming signal substantially equal to the determined voltage
value,” as recited in claim 16; or an analog means including “a generator
configured to output a voltage signal level as a function of the interval value;
and an integrating element to integrate the electrocardial signal with the
generator signal,” as recited in claim 22?
Appeal 2008-4553
Application 10/758,813

11
Findings of Fact
8. As depicted in Figure 2, Ekstrom discloses “a prior system for
obtaining the average ST segment depression,” the ST segment being a
relatively uniform segment between the S and T waves of an
electrocardiagram waveform (EKG) (Ekstrom, col. 3, l. 44, to col. 4, l. 17).
9. In this system:
An analog signal representing the EKG waveform is received
from appropriate electrodes attached to the patient’s body. This
signal is provided as an input to the prior art circuit at
terminal 10. The signal then passes through a variable signal
delay 12 to a subtractor 14. An undelayed version of the signal
is also provided to the subtractor via line 16 and to a trigger
generator via line 18. By appropriately selecting the amount of
signal delay 12, the subtractor 14 will subtract the PQ segment
of the EKG signal from the ST segment to obtain the ST
depression level. The resulting signal is displayed or subject to
further processing as indicated by block 20.
(Id. at col. 4, ll. 17-29.)
10. As depicted in Figure 3, Ekstrom also discloses an ST analyzer
that “eliminates the need for a variable signal delay and the superposition of
EKG segments” (id. at col. 4, ll. 35-45).
11. In this system, an “analog EKG signal from a patient is
received at terminal 30 and amplified by preamplifier 32” (id. at col. 4,
ll. 44-47). The “analog EKG signal is then delta modulated by modulator 34
yielding a digital representation of such analog signal shown as a binary bit
stream 38,” which is further processed (id. at col. 5, ll. 1-38).
12. Ekstrom also discloses sources of voltage (id. at col. 9, l. 25, to
col. 11, l. 49).
Appeal 2008-4553
Application 10/758,813

12
Analysis
Under 35 U.S.C. § 103, “the scope and content of the prior art are to
be determined; differences between the prior art and the claims at issue are
to be ascertained; and the level of ordinary skill in the pertinent art resolved.
Against this background, the obviousness or nonobviousness of the subject
matter is determined.” Graham v. John Deere Co., 383 U.S. 1, 17 (1966).
“The combination of familiar elements according to known methods is likely
to be obvious when it does no more than yield predictable results.” KSR
Int’l v. Teleflex Inc., 127 S. Ct. 1727, 1739 (2007).
Nearing discloses “a system and method for calculating a magnitude
of alternation in the T-waves of an electrocardiogram [ECG] signal” (FF 1).
In particular, Nearing discloses “applying a baseline wander removal filter to
the ECG data to remove low frequency artifacts” (FF 4). The method
comprises
determining an isoelectric value at each of a first isoelectric
point (point 1) in a first beat, a second isoelectric point (point 2)
in a second beat, and a third isoelectric point (point 3) in a third
beat of the ECG data; fitting a spline curve to the first three
isoelectric values; [and] subtracting the values of the spline
curve from the corresponding values of the ECG data.
(FF 5.) Nearing also discloses that preferably “a digitized ECG signal (i.e.,
ECG data) is received for processing” (FF 2).
Ekstrom discloses an analog system for processing electrocardiogram
data (FF 8). The method comprises subtracting analog signals (FF 9). We
agree with the Examiner that it would have been obvious to modify
Nearing’s system to subtract analog, rather than digital, signals. “The
combination of familiar elements according to known methods is likely to be
obvious when it does no more than yield predictable results.” KSR Int’l v.
Appeal 2008-4553
Application 10/758,813

13
Teleflex Inc., supra. In order to utilize an analog subtractor in Nearing’s
digital system, it would have been obvious to include a voltage generator to
generate a voltage substantially equal to the determined voltage value (i.e.,
the isoelectric value), so that this voltage could be subtracted from the
incoming voltage signal.
Appellant argues, however, that “[n]either Nearing nor Ekstrom (nor
any combination thereof) disclose analog components for generating a
voltage” (App. Br. 9). We are not persuaded. Ekstrom discloses sources of
voltage (FF 12). Thus, we agree that Ekstrom teaches or suggests analog
components for generating a voltage. In fact, Appellant acknowledges that
Ekstrom discloses an “analog circuit capable of creating a reference voltage”
(Reply Br. 8).
Appellant also argues that “[n]either Nearing nor Ekstrom (nor any
combination thereof) disclose applying a voltage to an incoming signal”
(App. Br. 9). We are not persuaded. Instead, we agree with the Examiner
that Ekstrom discloses applying a voltage to an incoming signal using a
subtractor (FF 9).
In addition, Appellant argues that “[b]oth Nearing and Ekstrom
manipulate digital ECG signals and not analog ECG voltage signals” (App.
Br. 10). In particular, Appellant argues that “Ekstrom digitizes the ECG
signal ‘as a binary bit stream’ as an initial step” and “Nearing states that ‘in
a first step a digitized signal is received for processing’” (id.).
We are not persuaded. Ekstrom does disclose a system in which an
analog EKG signal is delta modulated “yielding a digital representation of
such analog signal shown as a binary bit stream” (FF 11). However,
Appeal 2008-4553
Application 10/758,813

14
Ekstrom also discloses a prior art analog system (FF 8-9). The Examiner
relies on Ekstrom for teaching this analog system (Ans. 8).
Appellant also argues that the “Examiner has failed to provide a
sufficient suggestion or motivation in the prior art to combine or modify the
reference teachings so as to arrive at the claimed invention. While both
Nearing and Ekstrom analyze signal characteristics, they use different
digitizing techniques; different analysis hardware and they have diverging
objectives.” (App. Br. 10.) In particular, Appellant argues:
Ekstrom utilizes binary logic devices including flip flop circuits
and bilateral switches in analyzing a binary bit stream
representation of the ECG signal to determine a delta value.
Nearing is converting the ECG signal to integer values and
analyzing and comparing alternating waveforms with software
algorithms. The circuit components of Ekstrom are configured
to operate on a binary bit stream and will not function with the
integer base digitization used by Nearing.
(Id. at 10-11.)
In addition, Appellant argues that “Ekstrom uses bit processing
components to derive a difference value between two isoelectric points
within a beat,” whereas “Nearing uses software algorithms to develop
complexes for an even series of beats and an odd series of beats” (id. at 11-
12). Thus, Appellant argues that the “objectives of Ekstrom and Nearing are
clearly distinct and divergent” (id. at 12).
We are not persuaded. As noted by the Examiner, he is relying on
Ekstrom for disclosing a prior art analog system (Ans. 8). Thus, he is not
combining Ekstrom’s binary logic devices with Nearing’s system. In
addition, although Ekstrom is directed to determining ST depression
whereas Nearing is directed to calculating T-wave alternation magnitude,
Appeal 2008-4553
Application 10/758,813

15
both references relate to processing electrocardiograms (FF 1 & 8). Thus,
we do not agree that these references are so different that one of ordinary
skill in the art would not have had reason to combine them.
Appellant also argues that “Nearing’s reference value is not a direct
voltage value of the received signal during an interval of relative inactivity.
Instead, Nearing’s reference value is a spline curve with many approximated
values. . . . Therefore, Nearing . . . fails to disclose the claimed subject
matter . . . having to do with determining the reference value.” (Reply
Br. 8.) In addition, Appellant argues:
Even if Ekstrom’s analog circuit capable of creating a reference
voltage were somehow combinable with Nearing, the reference
voltage created by the combination would be different than the
Appellant’s reference voltage, at least in part, because
Nearing’s reference value is determined differently than that of
the Appellant and is a normalization approximation utilizing a
spline curve instead of a directly obtained sample voltage value.
(Id.)
We are not persuaded. As discussed above, we do not agree that
Nearing does not reference the waveform to the sample data at the
isoelectric points. Thus, we conclude that it would have been obvious to
include, in Nearing’s system, a voltage generator that generates voltage as a
function of the isoelectric values.
Conclusion
Appellant has not shown that the Examiner erred in concluding that
that it would have been obvious to include, in the alternation quantification
system disclosed in Nearing, “a reference voltage generator for generating a
voltage applied to the incoming signal substantially equal to the determined
voltage value,” as recited in claim 16; or an analog means including “a
Appeal 2008-4553
Application 10/758,813

16
generator configured to output a voltage signal level as a function of the
interval value; and an integrating element to integrate the electrocardial
signal with the generator signal,” as recited in claim 22. We therefore affirm
the obviousness rejection of claims 16 and 22. Claims 17-21 and 23-26 fall
with claims 16 and 22.
ORDER
We affirm the anticipation rejection of claims 27-32 and the
obviousness rejection of claims 16-26. However, we reverse the anticipation
rejection of claims 1-15.
No time period for taking any subsequent action in connection with
this appeal may be extended under 37 C.F.R. § 1.136(a).
AFFIRMED-IN-PART
lp
HEWLETT PACKARD COMPANY
P O BOX 272400, 3404 E. HARMONY ROAD
INTELLECTUAL PROPERTY ADMINISTRATION
FORT COLLINS CO 80527-2400