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WO

IN THE UNITED STATES DISTRICT COURT 

FOR THE DISTRICT OF ARIZONA 

IN RE: Bard IVC Filters Products Liability 

Litigation, 

No. MDL 15-02641-PHX DGC 

ORDER 

This multidistrict litigation (“MDL”) involves thousands of personal injury 

cases related to inferior vena cava (“IVC”) filters manufactured and marketed by 

Defendants C. R. Bard, Inc. and Bard Peripheral Vascular, Inc. (collectively, “Bard”). 

Bard has filed a motion to exclude the opinions of Dr. Derek Muehrcke. Doc. 7304. The 

motion is fully briefed, and the Court heard arguments on January 19, 2018. The Court 

will grant the motion in part. 

I. Background.

 The IVC is a large vein that returns blood to the heart from the lower body. IVC 

filters are small metal devices implanted in the IVC to catch blood clots before they reach 

the heart and lungs. This MDL involves seven different versions of Bard IVC filters – 

the Recovery, G2, G2 Express, G2X, Eclipse, Meridian, and Denali. 

 Each Plaintiff in this MDL was implanted with a Bard IVC filter and claims it is 

defective and has caused serious injury or death. Plaintiffs allege that Bard filters tilt, 

perforate the IVC, or fracture and migrate to neighboring organs. Plaintiffs claim that 

Bard filters are more dangerous than other IVC filters, and that Bard failed to warn about 
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the higher risks. Plaintiffs assert a host of state law claims, including manufacturing and 

design defects, failure to warn, breach of warranty, and consumer fraud and unfair trade 

practices. Doc. 303-1. Bard disputes Plaintiffs’ allegations, contending that overall 

complication rates for Bard filters are comparable to those of other IVC filters and that 

the medical community is aware of the risks associated with IVC filters. 

The parties intend to use various expert witnesses at trial, including medical 

professionals. Plaintiffs have identified Dr. Muehrcke, a cardiothoracic surgeon, as an 

expert witness on various issues in each of the five cases selected for bellwether trials. 

He has prepared case-specific reports that share certain opinions in common. Doc. 7307. 

Defendants ask the Court to exclude seven categories of opinions: (1) Bard filters have 

design defects; (2) adoption of opinions of other experts; (3) reasonable expectations of 

physicians regarding filter performance; (4) Bard filters have an “unacceptable” risk of 

caudal migration; (5) Bard acted unethically in selling its filters; (6) Bard’s state of mind, 

motive, and intent; and (7) the failure of Plaintiff Lisa Hyde’s filter resulted in an 

increased risk for arrhythmias and sudden death, and the need for an implantable 

defibrillator. Doc. 7304 at 2.1

 The Court will address each category.2

II. Legal Standard.

 Under Rule 702, a qualified expert may testify on the basis of “scientific, 

technical, or other specialized knowledge” if it “will assist the trier of fact to understand 

the evidence,” provided the testimony rests on “sufficient facts or data” and “reliable 

principles and methods,” and “the witness has reliably applied the principles and methods 

to the facts of the case.” Fed. R. Evid. 702(a)-(d). An expert may be qualified to testify 

based on his or her “knowledge, skill, experience, training, or education.” Id.

 The proponent of expert testimony has the ultimate burden of showing that the 

expert is qualified and the proposed testimony is admissible under Rule 702. See Lust v. 

 

1

 Page citations are to the numbers placed at the top of each page by the Court’s electronic filing system. 

2

 The bellwether cases are those brought by Plaintiffs Sherr-Una Booker, Lisa Hyde, Doris Jones, Carol Kruse, and Debra Mulkey. 
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Merrell Dow Pharm., Inc., 89 F.3d 594, 598 (9th Cir. 1996). The trial court acts as a 

gatekeeper to assure that expert testimony “both rests on a reliable foundation and is 

relevant to the task at hand.” Daubert v. Merrell Dow Pharm., Inc., 509 U.S. 579, 597 

(1993). Rule 702’s requirements, and the court’s gatekeeping role, apply to all expert 

testimony, not only to scientific testimony. Kumho Tire Co. v. Carmichael, 526 U.S. 

137, 147 (1999). 

III. Discussion. 

 A. Design Defects.

 Dr. Muehrcke is a cardiothoracic surgeon who received his specialty training at 

Harvard Medical School and Massachusetts General Hospital. Doc. 7307 at 2. He serves 

as Chief of Cardiothoracic Surgery at Flagler Hospital in St. Augustine, Florida, and is 

part of a private medical group that performs heart surgeries at seven area hospitals. 

Id. at 3. He implants or removes nearly 50 IVC filters per year, and has more than 

20 years’ experience treating patients with IVC filters. Id. at 2-3. 

 Defendants argue that Dr. Muehrcke is not qualified to offer design related 

opinions because he has never designed or tested an IVC filter and has no background in 

engineering, metallurgy, or materials science. Doc. 7304 at 3. Defendants ask the Court 

to exclude this design opinion: 

Due to the filters [sic] inadequate design, Ms. Booker’s filter tilted, became 

embedded in the vena cava, punctured through the vena cava and 

surrounding organs and structures, multiple strut fractures occurred, and 

filter fragments embolized to the heart. Specifically, the device’s 

inadequate migration resistance, and lack of strength and stability, caused 

by its weak anchoring hooks and lack of radial force and inadequate leg 

span to accommodate vessel distention were substantial factors in causing 

this device to migrate in a caudal direction, tilt, perforate the vena cava, and 

fracture. In reaching this opinion, I reviewed Ms. Booker’s medical records 

and radiology, and performed a differential diagnosis, and there is no other 

reasonable cause for the failures of the filter. 

Doc. 7307 at 10. Dr. Muehrcke offers similar opinions in other bellwether cases. See

Docs. 7307-1 at 9 (inadequate migration resistance and lack of strength and stability 
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caused Plaintiff Hyde’s G2 filter to migrate, tilt, perforate the IVC, and fracture); 7307-2 

at 9 (lack of strength and stability caused Plaintiff Jones’s Eclipse filter to fracture); 

7307-3 at 9 (inadequate migration resistance and lack of strength and stability caused 

Plaintiff Kruse’s G2 filter to migrate, tilt, and fracture). 

 The quoted opinion states that several specific structural characteristics of the 

G2 filter were substantial factors in causing it to migrate, tilt, perforate the IVC, and 

fracture. These include the filter’s inadequate migration resistance and lack of strength 

and stability caused by its (1) weak anchoring hooks, (2) lack of radial force, and 

(3) inadequate leg span. Doc. 7307 at 10. Clearly, Dr. Muehrcke is not qualified to 

testify about anchoring hooks, radial force, or leg span as an engineer, metallurgist, or 

product designer – he claims none of those qualifications. Thus, to the extent Plaintiffs 

offer his testimony as a design or engineering expert on characteristics of IVC filters, he 

is not qualified and will be excluded. 

 But Dr. Muehrcke identifies a different basis for his opinion: “In reaching this 

opinion, I reviewed Ms. Booker’s medical records and radiology, and performed a 

differential diagnosis, and there is no other reasonable cause for the failures of the filter.” 

Id. In other words, he reviewed Booker’s medical records and the x-rays of her filter and, 

as a thoracic surgeon with years of experience in implanting and removing IVCs, could 

find no other cause for the failure of her Bard filter than inadequate migration resistance. 

Dr. Muehrcke is qualified to give this opinion. As a trained and experienced thoracic 

surgeon who regularly uses IVC filters and engages in differential diagnoses, he is 

qualified to opine on factors that caused a filter’s failure – in this case, an inability to 

resist migration in the IVC. Whether he can also opine on more specific design problems 

such as a lack of strength and stability caused by weak anchoring hooks, lack of radial 

force, and inadequate leg span depends on whether his medical training and experience 

provides expertise on these specific aspects of IVC filters, something the Court cannot 

determine on this record. 
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 The Court will permit Dr. Muehrcke to opine that Ms. Booker’s problems arose 

because the Bard filter’s design had inadequate migration resistance. Whether he can 

provide more specific testimony on the cause of this inadequacy will depend on the 

foundation laid at trial. 

B. Reliance on Other Expert Reports. 

Defendants contend that Dr. Muehrcke’s opinions are unreliable because he adopts 

the opinions of Drs. Kinney, Kalva, Roberts, and Eisenberg. Doc. 7304 at 5-6. As the 

Court previously has found, Rule 703 permits experts to rely on opinions of other experts. 

See Doc. 9434 at 3-4 (citing In re Toyota Motor Corp. Unintended Acceleration Mktg., 

Sales Practices, & Prods. Liab. Litig., 978 F. Supp. 2d 1053, 1066 (C.D. Cal. 2013); 

E. Allen Reeves, Inc. v. Michael Graves & Assocs., Inc., No. 10-1393 (MAS), 2015 WL 

105825, at *5 (D.N.J. Jan. 7, 2015); Eaves v. United States, No. 4:07-CV-118-M, 2009 

WL 3754176, at *9 (W.D. Ky. Nov. 5, 2009)). Neither Dr. Muehrcke nor any other 

expert will be permitted at trial to simply parrot the opinions of other experts, or to vouch 

for those experts, but they can rely on opinions stated by other experts. 

C. Opinions Regarding the Reasonable Expectations of Physicians. 

Dr. Muehrcke offers this opinion in the Booker case: 

Based upon the information available to Bard at the time the filter was 

implanted in Ms. Booker, it was clear that the risks of the Bard . . . filter 

exceeded its benefits and that this filter did not perform in a manner 

reasonably expected by physicians and patients, nor in the manner 

represented by Bard. 

In using Bard’s . . . filter, physicians reasonably expected that if the filter 

was properly placed it would not migrate, tilt, perforate the vena cava and 

adjacent organs/structures, fracture, or have filter fragments embolize to the 

heart. In my opinion, because this filter failed in the manner previously 

described, Ms. Booker was exposed to risks that exceeded any benefits 

allegedly offered by this particular filter nor would a physician or patient 

reasonably expect this constellation of failure modes to occur. 

Doc. 7307 at 10. Similar opinions are rendered in the other bellwether cases. See 

Docs. 7307-1 – 7307-3 at 9; 7307-4 at 8. 
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 Defendants ask the Court to exclude these opinions on the ground that Dr. 

Muehrcke cannot speak on behalf of all physicians regarding reasonable expectations of 

IVC filters. Docs. 7304 at 6-8; 8224 at 7-10. Defendants claim that Dr. Muehrcke is not 

qualified to offer such opinions and has identified no reliable methodology, noting that he 

cites no supporting scientific literature, has conducted no survey as to what other 

physicians think, and acknowledges that the risk-benefit analysis performed by individual 

physicians is a subjective art form, not a science. Id. 

 Plaintiffs assert that Dr. Muehrcke is not purporting to speak on behalf of other 

physicians, but instead is offering an opinion about the adequacy of Bard’s warnings. 

Doc. 7813 at 10. Plaintiffs state that in “giving the opinion that the Bard G2 filter ‘did 

not perform in a manner reasonably expected by physicians and patients, nor in the 

manner represented by Bard,’ Dr. Muehrcke is clearly opining that the warnings and 

other information provided by Bard to physicians was insufficient.” Id. at 10-11 (quoting 

Doc. 7307-1 at 9). Plaintiffs further state that “Dr. Muehrcke’s opinion – which 

expressly mentions ‘the manner represented by Bard’ – is an opinion that Bard did not 

provide physicians with adequate information about the risks presented by its IVC 

filters.” Id. at 11. Plaintiffs conclude by stating that based on his extensive experience 

implanting and removing IVC filters, Dr. Muehrcke’s “warnings opinions” are reliable. 

Id. at 12. 

 Given this response and Plaintiffs’ focus on Dr. Muehrcke’s “warnings opinions,” 

it is not clear whether Plaintiffs intend to have Dr. Muehrcke testify at trial about the 

reasonable expectations of physicians regarding filter performance. He clearly expresses 

such opinions in each report. See, e.g., Doc. 7307 at 10. He also opines in each report 

that “the risks of the Bard . . . filter exceeded its benefits” and that each Plaintiff “was 

exposed to risks that exceeded any benefits allegedly offered by [their] particular filter.” 

See id. Plaintiffs do not address these risk-benefit opinions in their response brief. 

The admissibility of similar opinions was addressed in a recent order concerning 

Drs. Kinney, Roberts, and Kalva. Doc. 9434. Given the doctors’ qualifications and 
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experience as interventional radiologists, the Court found that they should not be 

precluded from testifying about what disclosures reasonable physicians expect to receive 

from manufacturers of IVC filters. Id. at 6-9. With respect to testimony about what 

physicians would have done with additional information, however, the Court concluded 

that the admissibility of such testimony must be determined at trial. Id. at 9. 

The Court reaches similar conclusions regarding Dr. Muehrcke. Defendants do 

not dispute that Dr. Muehrcke is a well-qualified cardiothoracic surgeon. During the past 

20 years, he has implanted and removed hundreds of IVC filters, including those 

manufactured by Bard. Doc. 7307 at 2-3. Under Rule 702 and Daubert, expert 

testimony “is reliable if the knowledge underlying it has a reliable basis in the knowledge 

and experience of the relevant discipline.” Primiano, 598 F.3d at 565 (citation omitted). 

The Court finds that Dr. Muehrcke has sufficient knowledge and experience to offer his 

opinion as to the information reasonable physicians expect to receive from IVC 

manufacturers, and whether physicians who implant IVC filters reasonably expect a 

properly implanted filter to tilt, perforate the IVC, or fracture and migrate to neighboring 

organs. Defendants may, of course, challenge the reliability of these opinions through 

cross examination or qualified experts of their own. 

Dr. Muehrcke’s risk-benefit opinions are more problematic. Whether the risks of 

using a particular medical device outweigh the benefits is a fact- and patient-specific 

decision not amenable to broad generalizations about what a “reasonable” patient or 

physician would decide. The propriety of testimony on this subject will depend heavily 

on the context and relevancy of the question. The Court will make these rulings during 

trial. 

D. Opinions on the “Unacceptable” Risk of Migration.

In his report for the Booker case, Dr. Muehrcke offers this opinion regarding the 

G2 filter’s migration risk: 

Bard had been aware since late 2005/early 2006 of the need to correct the 

“unacceptable” caudal migration risk with the G2 filter. Bard was also 

aware that caudal migration leads to tilt, perforation, penetration, 
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irretrievability, and fracture. Despite this knowledge, Bard did nothing to 

inform physicians or patients of these safety risks; choosing instead to 

launch two more filters, the G2X and Eclipse, prior to launching a filter, the 

Meridian, that addresses caudal migration. Ms. Booker’s filter ultimately 

failed in the manners expected of the G2 filter – e.g., caudal migration, tilt, 

irretrievability, perforation/penetration, and fracture – which the Meridian 

was intended to correct. In my opinion, Bard should have removed the G2 

filter from the medical market and medical facilities given its knowledge of 

the “unacceptable” risk of caudal migration[.] 

Doc. 7307 at 8. Similar opinions are set forth in the reports for two other bellwether 

cases. See Docs. 7307-1 at 8 (Hyde), 7307-2 at 8-9 (Jones).3

 

 The Court concludes that Dr. Muehrcke should not be permitted to opine on Bard 

filter failure rates. Even if a physician could be qualified to render such opinions, he has 

not conducted any study of IVC filter complication rates. Plaintiffs argue that his 

opinions are based on personal experience with IVC filters and his training and 

experience as a doctor, but he does not state that he tracked failure rates in his personal 

cases. Dr. Muehrcke did review a number of medical articles regarding IVC filter 

complication rates, including the Deso article, which concerned a literature search 

regarding complications associated with various IVC filter designs. Doc. 7302-2.4

 But 

even if these articles suggest that Bard filters have higher complication rates than other 

filters, Dr. Muehrcke does not claim to have taken any steps to verify their conclusions, 

and merely restating those conclusions does not constitute a reliable basis for rendering 

an expert opinion under Rule 702. Dr. Muehrcke cannot simply repeat the opinions of 

others as his own when he has done nothing to verify the accuracy of the opinions. See 

In re Matter of Complaint of Ingram Barge Co., 2016 WL 4366509, at *4 (N.D. Ill. Aug. 

16, 2016) (“[The expert’s] opinions . . . do not rely ‘in part’ on the purported expertise of 

 

3

 Defendants assert that this opinion also is included in the report for the Mulkey case (Doc. 7304 at 12), but the cited page is not included in the copy of the report filed with the Court (see Doc. 7307-4 at 7-8). 

4

 The article is “Evidence-Based Evaluation of [IVC] Filter Complications Based on Filter Type,” co-authored by Drs. Steven Deso, Ibrahim Idakoji, and William Kuo, and published in Seminars in Interventional Radiology (Vol. 33 at 93-100, No. 2/2016). 
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other testifying experts. Rather, [the expert] repeats and concurs with their opinions, 

without additional analysis. The Court does not need an expert to reiterate other experts’ 

testimony.”).

His opinion that the G2 filter poses an “unacceptable risk” of caudal migration 

is based on a Bard internal document. A report titled “G2 Caudal Migration Update,” 

prepared by Bard product quality engineer Natalie Wong, states that in certain 

circumstances the G2 filter had an “[u]nacceptable risk” of caudal migration per 

Bard’s failure modes and effects analysis. Doc. 7825 at 21. Again, however, Dr. 

Muehrcke does not identify any steps he has taken to verify the conclusion in the Wong 

report. Nor does he identify the person or entity to whom the risk he mentions is 

unacceptable – physicians, patients, medical manufacturers, the FDA, etc. Indeed, in his 

deposition he steadfastly refused to identify an acceptable failure rate, saying only that it 

should be as close to zero as possible. Doc. 7304 at 10 (quoting Dep. Tr. 65:2-5). 

Dr. Muehrcke could opine, as a treating physician who must make decisions about 

IVC filter use, that Bard should have disclosed any risks it found in its products that 

would be unacceptable to doctors and patients. But he cannot opine that Bard filters 

present an “unacceptable risk” unless that opinion is based on sufficient facts and data he 

has identified, to which he has applied reliable principles and methods. Fed. R. Evid. 

702(b), (c). Merely repeating conclusions in the Wong report as his own opinion does 

not meet this requirement. 

 Nor can Dr. Muehrcke opine about the failure rates of Eclipse filters. Plaintiffs 

identify no study or articles he reviewed on Eclipse failure rates, much less any he 

verified. 

E. Opinions Regarding State of Mind and Ethics. 

Defendants argue that Dr. Muehrcke’s opinions about what Bard knew or should 

have done, and Bard’s underlying motives and intent, are classic jury questions outside 

the bounds of appropriate expert testimony. Doc. 7304 at 12-13. Plaintiffs state that the 

doctor will not opine as to motives or intent, but contend that the degree of Bard’s 
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knowledge about the dangers posed by its filters is relevant to the failure-to-warn claims. 

Doc. 7813 at 17-18. 

 Dr. Muehrcke will not be permitted to opine about Bard’s knowledge, intent, or 

ethics. See Doc. 9434 at 17. He does not purport to be an expert on corporate 

information processing and he has not conducted any study of Bard internal operations, 

information gathering, or corporate ethics. Plaintiffs propose to have him opine about 

what Bard knew based on selected documents, but identify no expertise that enables him 

to opine on Bard’s knowledge. Dr. Muehrcke may opine that Bard should have provided 

warnings to physicians and patients if it knew of excess risks, but it will be up to other 

evidence to show that Bard had such knowledge. 

F. Opinions on the Future Medical Risks and Needs in the Hyde Case. 

 Dr. Muehrcke opines that as a result of the failure of Plaintiff Hyde’s G2 filter, she 

is at risk for arrhythmias and sudden death, and will need an implantable defibrillator. 

Doc. 7307-1 at 8-9. Defendants challenge this opinion on the ground that Dr. Muehrcke 

cannot quantify the future medical risks and needs. Doc. 7304 at 13-14. The Court 

concludes that it will be better able to address this issue in the context of the Hyde trial 

and after trying a few bellwether cases, and therefore will withhold ruling until the Hyde 

case is ready for trial. Defendants may reassert their arguments in a motion in limine. 

IT IS ORDERED that Defendants’ motion to exclude the opinions of Dr. Derek 

Muehrcke (Doc. 7304) is granted in part and denied in part as set forth in this order. 

 Dated this 22nd day of January, 2018.