ROBERT J. CINDRICH, District Judge
This is a products liability action involving a defective artificial heart valve. Pending is defendants' ("Shiley") motion for summary judgment on plaintiff's ("Norris") claim for damages attributable to her stroke. Magistrate Judge Caiazza recommended that the motion be granted for the failure of Norris's expert to meet the standards of Daubert v. Merrell Dow Pharmaceuticals, Inc., 509 U.S. 579, 125 L.Ed.2d 469 (1993), and Third Circuit authority construing Daubert.
The magistrate judge's report and recommendation ably sets out the background, evidence, and applicable legal standards, which we need not repeat here. Because the question of admissibility of the opinion of Norris's expert Diane Nugent, M.D., was compelling, however, and because the issue was essentially dispositive, we decided to conduct further proceedings. By order dated August 6, 1999, the court identified the specific issue on which defendants' motion hinged; invited further briefs and evidentiary materials focused on this issue; and scheduled an evidentiary hearing. There is undisputed evidence in this case that all artificial heart valves, indeed all foreign bodies in the bloodstream, create risks of the formation of thrombuses, or blood clots. The narrow issue on which we sought further evidence was how Dr. Nugent could distinguish between clots that could form on the defective portion of Norris's heart valve, for which Shiley might be liable, and the clots that might form, and indeed did form, on the non-defective portions of Norris's artificial valve, for which Shiley would not be liable.
Both sides submitted the briefs requested. Though invited to attach her five most persuasive evidentiary excerpts, and despite having the burden on this issue, In re Paoli RR Yard PCB Litigation, 35 F.3d 717, 744 (3d Cir. 1994), Norris did not attach evidence to her brief, relying instead on her other filings and the hearing testimony to support her contentions.
The hearing was held on September 2, 1999. Dr. Nugent appeared by live videoconference from California. She is an expert in hematology, blood platelet physiology, bleeding, and clotting abnormalities, and was unchallenged as to her qualifications. It was her opinion that the fractured strut on Norris's valve created increased risk of stroke-causing blood clots beyond the risks associated with an intact heart valve. She cogently explained that the broken strut left jagged surfaces on the affected metal. These surfaces tend to deform blood cells which they contact. Deformed blood cells release sticky, fibrous proteins which lead to clot formation. Moreover, the area of the heart where the valve is implanted is one of high turbulence, in that blood is moving through the area at significant pressure and volume. A broken strut also vibrates microscopically and at a high frequency, which in her opinion leads to further cell breakdown, in a process she compared roughly to the effects of kitchen blender. In addition, the metal around the fracture is smooth, unlike the fabric by the which the artificial valve is sewn onto the human heart, where other blood clots were found. The blood clots on the fabric, referred to in Norris's medical records as "vegetation," would tend not to be released because they were attached to an adhesive foundation, unlike the shiny, smooth metal surrounding the fracture. The operation of these principles of physics, fluid dynamics, and hematology led Dr. Nugent to her opinion to a reasonable degree of medical certainty that the fracture in Norris's valve, and not the clot-creating tendencies of the non-defective part of the valve, contributed to clot creation and the causation of Norris's stroke.
We are to measure Dr. Nugent's testimony against the standards for reliability suggested by the Supreme Court and the Third Circuit. These are:
(1) Whether a method consists of a testable hypothesis;
(2) whether the method has been subject to peer review;
(3) the known or potential rate of error;
(4) the existence and maintenance of standards controlling the technique's operation;
(5) whether the method is generally accepted;
(6) the relationship of the technique to methods which have been established to be reliable;
(7) the qualifications of the expert witness testifying based on the methodology; and
(8) the non-judicial uses to which the method has been put.
Paoli, 35 F.3d at 742 n. 8; accord Heller v. Shaw Industries, Inc., 167 F.3d 146, 152 (3d Cir. 1999). Our use of these standards is part of the flexible exercise of our gatekeeping function which we have broad latitude to determine. Kumho Tire Co. v. Carmichael, 119 So. Ct. 1167, 143 L.Ed.2d 238, 251-53 (1999). That being said, we have no reason not to apply the factors collected in Paoli to this case.
Some of these factors were covered by counsel for Shiley on cross-examination. Dr. Nugent's method consists of a testable hypothesis, but she has not examined blood flow through a fractured valve to test her theory. She stated that such testing would be too expensive for a person in Norris's position, and invited Shiley to fund such research into the effects of fractured valves on blood cells. She also stated that such studies were not otherwise likely to be performed because researchers do not study faulty devices prospectively. In other words, if a medical device is defective it should be promptly remedied, instead of being accepted as faulty and examined for its effects on the human body.
She stated that there is nothing in the medical literature which she knows about comparing intact and fractured heart valves to determine clot formation and stroke risk. Thus, she could not support her theory with peer review.
By the same token, she could not comment on the known or potential rate of error. She also did not cite standards controlling the technique's operation.
She testified that the bases for her opinion are commonly accepted, but this testimony was not followed up with questions identifying others who accepted her theory. Norris did present excerpts from the deposition testimony of her other physicians, who have the same opinion on causation as Dr. Nugent. But by definition this is not evidence of general acceptance; it is rather specific acceptance of this theory in this case.
As for relating her theory to methods which have been established to be reliable, Dr. Nugent was adept at describing her theory in a way that seemed reliable to the court's ears in its reference to the process of how living cells are disrupted by foreign objects.
Otherwise, we found little specific comparison between her theory and other methods established as reliable. When asked if she ever investigated blood flow through a valve fracture to determine disruption of blood cells, such disruption being known as shear stress, she stated that she had not performed such an experiment, and that comments about the results would be unreliable without instruments to measure the effects. The court's attention was not called to the non-judicial uses of Dr. Nugent's theory. Apart from this case, she did not elaborate on other times or places where her theory was used.
Dr. Nugent acknowledged that neither she nor anyone else knows when the fracture in question occurred, which also places considerable limits on the reliability of her opinion because of the lack of a demonstrable temporal connection between the defect and the injury.
In sum, we took briefs and heard argument and testimony in addition to reviewing all the information presented to Magistrate Judge Caiazza before and after his report and recommendation. Norris's argument and evidence did not persuade us that her opinion meets the applicable standards for reliability of expert testimony.
Accordingly, defendants' Motion for Partial Summary Judgment on Plaintiff's Claim for Damages Attributable to Her Stroke, Doc. No. 65, is GRANTED. The report and recommendation of Magistrate Judge Caiazza dated May 26, 1999, Doc. No. 131, together with this memorandum order, are ADOPTED as the opinion of the court.