| | Initial results of wireless pressure sensing for endovascular aneurysm repair: The APEX Trial—Acute Pressure Measurement to Confirm Aneurysm Sac EXclusionPresented at the Society for Vascular Surgery, June 16-19, 2005, Chicago, Ill. Received 25 July 2006; accepted 30 September 2006. ObjectiveComplete exclusion and depressurization of the aneurysm sac is the prime goal of endovascular repair (EVAR) of abdominal aortic aneurysms. Thus, any EVAR that results in a type I or III endoleak has been classified as a technical failure. The current method to detect endoleaks uses intraoperative aortography. However, aortography is limited by its subjective nature, inability to quantify the significance of the endoleak, and artifacts such as bowel gas that may mimic an endoleak. In addition, repetitive contrast injection may impair renal function. To increase the efficacy and safety of intraoperative endoleak detection, a wireless pressure-monitoring system has been developed and tested in the clinical setting. MethodsThe APEX trial (Acute Pressure Measurement to Confirm Aneurysm Sac EXclusion) is a prospective, multicenter/international trial sponsored by CardioMEMS to evaluate the safety and efficacy of the EndoSure wireless pressure sensor for EVAR. The 30 × 5 × 1.5-mm sensor contains no battery and is powered externally with radiofrequency energy. The sensors are extremely stable, operate over the full physiologic range of pressures, and have a resolution of 1 mm Hg. A total of 90 patients were enrolled at 12 sites, 76 of whom were eligible for analysis. The sensor was implanted via the contralateral femoral artery at the time of EVAR. The sac pulse pressure was measured with both an angiographic catheter and the sensor after deployment of the main endograft but before the deployment of the contralateral limb (type I endoleak equivalent). Sac pressure was again measured with the sensor after deployment of the contralateral limb and completion of the EVAR. Data were collected in a prospective manner. ResultsIn all of the eligible patients (n = 76), the initial sensor pressure measurement agreed closely with the angiographic catheter pressure measurement of the type I endoleak equivalent. At the completion of the procedure, there was agreement between the sensor measurement and angiography regarding the presence or absence of a type I or III endoleak in 92.1% (n = 70) of the measurements. Overall, the sensitivity was 0.94 and the specificity was 0.80 for detecting type I or III endoleaks. Final pulse pressures decreased significantly compared with baseline measurements. ConclusionsImplantation of the wireless pressure sensor is safe, and remote aneurysm sac pressure sensing is feasible. It was a valuable guide in evaluating the completeness of the EVAR procedure. Long-term study will be needed to prove its efficacy for postoperative surveillance. The primary goal of any abdominal aortic aneurysm (AAA) treatment is to reduce the pressure in the aneurysm sac and prevent rupture. Complete exclusion will allow depressurization of the sac, whereas failure to exclude the aneurysm from the systemic circulation results in continued pressurization.1, 2, 3, 4 Endoleaks, especially type I and III leaks, lead to continued increases of sac pressure and, therefore, have been defined as technical failures.4, 5 Currently, the completeness of exclusion or absence of endoleaks is evaluated by intraoperative angiography. The presence of continued perfusion of the sac with contrast probably correlates well with sac pressurization in most cases. However, the absence of contrast filling of the sac is not always an accurate predictor of the absence of endoleaks. First, in the absence of outflow, contrast material does not easily flow into the sac. Second, imaging the AAA sac is difficult: the sac is located deep inside the abdomen, and this makes angiographic imaging challenging, unlike in the carotids or the lower extremities. To increase the sensitivity for detecting endoleaks, most (if not all) operators use digital subtraction angiography, which can lead to false-positive findings due to artifacts from bowel gas, respiration, and pre-existing contrast inside the sac. Uncertainty regarding the presence or absence of endoleaks on completion angiography may lead to multiple contrast injections in different projections, thus leading to an increased risk of contrast-induced nephropathy and increased radiation exposure for both the patient and surgeon. However, measurement of sac pressure gives a physiological assessment of operative success, because it directly measures the most important end point of endovascular aneurysm repair (EVAR): reduction in sac pressure.1, 2, 3, 4 Previous studies have used direct sac pressure measurement with an angiographic catheter. The obvious drawback of this technique is the interference of the catheter with the seal formed by the stent graft. Additionally, the catheter cannot be kept inside the body for a prolonged period of time. To improve the outcome of EVAR, a wireless and batteryless implantable pressure sensor was developed (EndoSure sensor; CardioMEMS, Inc, Atlanta, Ga). The sensors are designed to operate over the full physiologic range of pressures and have a resolution of 1 mm Hg. The APEX trial (Acute Pressure Measurement to Confirm Aneurysm Sac EXclusion) was a prospective, multicenter/international trial to evaluate the safety and efficacy of the EndoSure sensor for detecting intraoperative type I and III endoleaks during EVAR with commercially available stent grafts. Materials and methods  The objective of this study was to determine whether intraoperative EndoSure sensor pulse pressure measurements correlate with angiographic findings in terms of the presence or absence of type I or III endoleaks. Systolic, diastolic, mean, and pulse pressures in the sac were measured by using the EndoSure sensor during and at the completion of stent graft placement. In addition, a noninvasive blood pressure cuff and an arterial line were used to measure systemic blood pressure. The primary efficacy variable was the correlation between the EndoSure sensor and angiography to confirm sac exclusion during the endovascular stent-graft procedure. The clinical hypothesis was that a reduction in pulse pressure of 30% or more from the initial EndoSure sensor sac pulse pressure measurement (baseline; before aneurysm exclusion) would be associated with a sealed sac, whereas a less than 30% reduction in pulse pressure would indicate a type I or III endoleak. Because such endoleaks are infrequently encountered during the EVAR procedure, we defined a type I endoleak equivalent. A type I endoleak equivalent was defined as the endoleak seen after the release of the stent graft’s main body but before the deployment of the contralateral limb. Physiologically, this is equivalent to a large distal type I endoleak. The sac pressure measurement was repeated after the completion of the EVAR (after all the components were deployed and touch-up ballooning was performed as indicated). Secondary efficacy parameters of interest were pressure measured on the day of discharge, procedure evaluation and procedure difficulties, assessment of the access site at the discharge evaluation, and detection of a sensor signal at the 30-day evaluation. Safety parameters analyzed were adverse events and deaths occurring within the 30-day evaluation period. Patients completed the baseline screening requirements at the preoperative examination and received a stent graft and the EndoSure sensor within the following 12 weeks. Various pressures were measured during surgery. Patients were evaluated at discharge and at the 30-day follow-up for adverse events. Angiographic and computed tomographic (CT) images were submitted to a core laboratory (Cleveland Clinic Peripheral Vascular Core Lab, Cleveland, Ohio) and independently reviewed by a qualified radiologist. Patient selection All patients who met the acceptance criteria for insertion of a bifurcated, modular endovascular stent graft for the treatment of infrarenal AAAs or aortoiliac aneurysms according to the instructions for use of the selected endograft were candidates for implantation of the EndoSure sensor. The only unique anatomic requirement for the implantation of the sensor was that CT scanning should demonstrate that adequate space was available for the sensor within the aneurysm sac (>10 mm after stent-graft insertion). In one patient, this criterion was not met, and the sensor was not inserted. The sensor is typically placed in the largest segment of the aneurysm sac, although this is not strictly necessary or always achievable. In addition, the patients needed to agree to comply with the follow-up requirements of the study. Standard exclusion criteria for EVAR were specified. In the United States, only commercially available stent grafts were used. Food and Drug Administration and local institutional review board approval were obtained before the clinical trial was initiated, and written informed consent was received in all cases. The EndoSure sensor The sensor has a nitinol basket surrounding the electronic components (Fig 1). It has no battery and is powered externally. In vivo testing has shown that the sensor continues to function over several years and is extremely stable. It is calibrated during the deployment procedure and does not require recalibration. The sensor itself is composed of flexible plates bearing inductor windings inside a hermetically sealed reference cavity. A change in the pressure surrounding the EndoSure sensor will change the position of the plates, thereby changing the capacitance and resonant frequency of the sensor. The change in resonant frequency can be monitored by external electronics (antenna), and this allows measurement of the pressure in the aneurysm sac. Sensor interrogation results in a real-time pressure trace of the sac pressure, which is displayed on an external monitor (Fig 2). The EndoSure sensor is mounted inside a 14F sheath, which is introduced over an existing wire. The sensor is attached to a tether wire, which is used to maintain the position of the sensor during retrieval of the delivery system. This tether wire and the super-stiff wire that was used for over-the-wire delivery exit from the proximal end of the delivery system. Implantation technique Although some cases were performed percutaneously, the vast majority of the cases were performed via bilateral femoral cutdowns. After the common femoral arteries were exposed, a single wall puncture was performed on the side of the main endograft insertion, and a guidewire was introduced into the descending aorta. This guidewire was exchanged for a super-stiff support wire, and the endograft or the delivery sheath was introduced. To prevent the ipsilateral wire (the side of the main body insertion) from passing through the nitinol basket of the EndoSure sensor, the ipsilateral wire was introduced before the EndoSure sensor was deployed (Fig 3). The same steps were performed in the contralateral femoral artery, and a super-stiff wire was placed into the thoracic aorta. The EndoSure sensor delivery sheath was then introduced over this super-stiff wire. Once the EndoSure sensor was located inside the sac, the outer sheath was withdrawn over the pusher rod (Fig 3). Care was taken so that the EndoSure sensor was kept slightly proximal to the desired target site. Then, the delivery system (including the metal jacket that was protecting the EndoSure sensor) was retrieved from the body, leaving behind only the sensor and the tether wire attached to the sensor (Fig 3). During this process, the sensor delivery system was exchanged over the tether wire and the super-stiff wire, thereby keeping the sensor position stable and maintaining wire access to the aneurysm with the super-stiff wire. Once the sensor delivery sheath was completely withdrawn from the patient, a pigtail catheter was introduced over the super-stiff wire. Calibration of the EndoSure sensor and baseline sac pressure measurements with both the angiographic catheter and the sensor were also performed at this time. Systemic blood pressure measurement was recorded with an arterial line as well as with the brachial cuff. Angiography was then performed via the pigtail catheter for endograft deployment while the sensor was kept inside the sac (Fig 3). The main body of the bifurcated endograft was then deployed, leaving a large type I endoleak equivalent. At this time, sac pressure measurements were performed with both the angiographic catheter and the EndoSure sensor to measure the type I endoleak equivalent. Then, cannulation of the contralateral stump was performed with standard techniques, and the contralateral limb was deployed. The use of the touch-up balloon was left to the physician’s discretion. At this point, because the EndoSure sensor was confined within the sac and isolated from the circulation, the tether wire was pulled to release the sensor. After all the necessary steps were accomplished, a completion aortogram was performed, and the presence and type of endoleak were recorded. In addition, the systemic blood pressure and the sac pressure with the EndoSure sensor were recorded. These pressure measurements were performed before leaving the procedure suite. Additional pressure measurements were performed at 30 days to confirm sensor function. Ongoing pressure measurements continue to be taken at regular patient follow-up intervals (ie, 6 months, 1 year, 2 years, and so on) and will be the subject of future articles. Results After completion of a 15-patient feasibility trial in which sensor accuracy was confirmed by simultaneously measuring the pressure wirelessly and through a standard angiographic catheter that had been left in the aneurysm sac after stent-graft deployment, 90 patients were enrolled at 12 sites in 4 countries between July 2004 and January 2005. All patients were fully compliant with the inclusion and exclusion criteria at the screening visit except for one who did not have adequate space in the aneurysm sac for implantation of the EndoSure sensor. Before hospital discharge, protocol deviations, typically a missed measurement, prevented analysis of 14 patients, and these patients were excluded from the per-protocol population. Therefore, the intention-to-treat population included 90 patients, and the per-protocol population included 76 patients. Of the 90 patients enrolled, only 1 died before hospital discharge. Of the surviving patients, all completed the 30-day follow-up evaluation, except for one who died on day 29 before the follow-up visit. Patient demographics Of the 76 patients in the per-protocol population, 86.8% (n = 66) were male. The mean age of the per-protocol population was 72.3 years (range, 56-88 years). The mean weight was 81.6 ± 15.3 kg or 180.2 pounds (±33.7 pounds). Type of stent graft used and basic operative information The mean maximum aneurysm diameter in the per-protocol population was 5.48 ± 1.07 cm (range, 3.85-10.1 cm; the single case with a <4-cm AAA was in a patient who had a saccular aneurysm). The most commonly used stent grafts in the per-protocol population were the Zenith (Cook, Indianapolis, Ind) and Excluder (WL Gore, Flagstaff, Ariz; n = 27 for both), which comprised 71% of the implants. Other stent grafts included 8 AneuRx (Medtronic, Santa Rosa, Calif) in the United States and 3 Talent (Medtronic) and 11 Apolo (Nano Endoluminal, Florianopolis, Brazil) at outside the United States sites. There was no significant difference between intraoperative endoleak rates among the different types of stent grafts. The mean estimated blood loss for the intention-to-treat population was 436 ± 387 mL, and the mean operating room time was 190 ± 98 minutes. In the per-protocol population, the mean estimated blood loss was 471 ± 387 mL, and the operative time was 205 ± 87 minutes. Primary efficacy parameter In all of the per-protocol patients, the initial pressure measurement during the type I endoleak equivalent agreed between the angiographic catheter and the sensor (Fig 4). At the completion of the procedure, there was final agreement between the EndoSure sensor measurement and angiography for determination of a type I or III endoleak in 92.1% (n = 70; P < .05) of the patients (Table). At the completion of the procedure, the pulse pressure decreased significantly compared with the baseline measurement (Fig 5). Sealing of the sac was associated with a mean decrease in pulse pressure of 46%. | | |  | Angiography | Sensor | Total | |
|---|
| Pressure decrease <30% | |
|---|
| Yes | No | |
|---|
| Endoleak present | 4 | 1 | 5 | | | Endoleak absent | 5 | 66 | 71 | | | Total | 9 | 67 | 76 | | | | |
During the clinical trial, there were several occasions when real-time pressure sensing during EVAR was used to determine the origin of the endoleak and its significance in terms of pressurization of the sac. Such an example is shown in Fig 6. Owing to this physiological evaluation, the AAA was treated effectively without multiple contrast injections. There were five instances of disagreement between the EndoSure sensor and angiography (Table). In four of these cases, postexclusion measurements showed a less than 30% reduction in sac pressure, although there was no visible endoleak on angiography (false positive). Serial pressure measurements on these patients subsequent to EVAR demonstrated a gradual reduction of pulse pressure within the aneurysm sac. In one patient, pulse pressure as measured by the EndoSure sensor decreased by more than 30% even though angiography revealed what was interpreted as a small type I endoleak (false negative). The investigator did not consider the endoleak significant and chose not to treat it; at the 30-day follow-up evaluation, there was no further evidence of the endoleak, and the sac pressure remained stable. In 96.6% (n = 87) of the entire intention-to-treat population and 97.3% (n = 74) of the per-protocol population, the sensor signal could be detected at the 30-day evaluation. In one patient, the signal could not be detected at the 30-day measurement but was present on subsequent visits. One patient died before discharge, and one patient died after discharge but before the 30-day evaluation. Through the 30-day evaluation, 21.1% (n = 19) of the patients experienced 23 anticipated adverse events, and 17.7% (n = 16) of the patients experienced 18 other unanticipated adverse events. Adverse events were classified as unanticipated if they were not included in the investigational plan. The most common anticipated adverse events were arterial occlusion (not related to the sensor), delayed wound healing, and endoleaks. The most frequent unanticipated adverse events were pain, fever, and hospitalization, all of which were probably related to the EVAR procedure. There were no adverse device events (ie, due to the sensor). There was also no evidence of device migration, and sensor performance was not affected by the presence of thrombus in the sac. Deaths Two deaths through the 30-day evaluation period were reported. Both deaths were classified by the investigator as nonrelated to the sensor or the implantation procedure. The first death was an 85-year-old man whose comorbidities included hypertension and arthritis. This patient received an AneuRx stent graft in a procedure that lasted approximately 3 hours. Estimated blood loss was 1000 mL, and the patient received 800 mL of packed red blood cells. The family informed the site coordinator that the patient died before the 30-day follow-up visit. The investigator was told that the cause of death was probably due to a myocardial infarct. The second death was a 72-year-old man whose comorbidities included a history of myocardial infarction, high cholesterol, and hypertension. He received a Zenith stent graft in a procedure that lasted approximately 4.5 hours. Estimated blood loss was 1600 mL, and he received 1000 mL of packed red blood cells. There were no procedure difficulties. The patient developed acute pulmonary edema shortly after leaving the operating room, and the edema worsened. Cardiopulmonary resuscitation was performed, but the patient died. Nonevaluable patients Of 90 patients who received the EndoSure sensor during the study, 14 (15.6%) were classified as nonevaluable and were excluded from the per-protocol analyses. These patients had protocol deviations mostly due to missing data points, thus leading to exclusion from the per-protocol analysis. There was a definite learning curve associated with refining the technique for insertion of the implants, interrogation of the sensor, operation of the electronics, and proper completion of the case report forms. In 12 cases, proper EndoSure sensor function was confirmed after surgery, and further operator training resulted in improved compliance with the study protocol. Discussion Effective EVAR requires complete exclusion of the aortic aneurysm sac. The presence of most type I or III endoleaks is considered a technical failure and needs to be identified and addressed at the time of implantation.5 Currently, the standard tool used for intraoperative endoleak assessment is angiography. However, angiography has many shortcomings: it may not be accurate in obese patients; interpretation can be difficult when artifact exists (Fig 6); and, most relevantly, there is the inability to assess sac pressure reduction and thus understand the physiologic significance of a visible endoleak. This study was designed to evaluate the clinical usefulness of a wireless implantable pressure sensor and the value of noninvasive sac pressure measurements performed during operative insertion of a stent graft. Specifically, it was our aim to determine whether the EndoSure sensor can aid in the assessment of sac exclusion during EVAR. Because true type I or III endoleaks are rarely encountered during EVAR, endoleak after main graft insertion but before contralateral limb insertion was defined as a type I endoleak equivalent. Baseline pressure was measured during the type I endoleak equivalent, and pressure was measured again at the end of the case to confirm sac exclusion and pressure reduction. The accuracy of the EndoSure sensor to diagnose the endoleak equivalent proved to be 100%, with no false-positive or -negative results. In addition, measurement of the sac pressure with simultaneous pressure readings with an angiographic catheter or sheath showed excellent correlation between the two values and confirmed sensor accuracy. Although anecdotal cases have been reported with another type of wireless pressure sensor,6, 7 this is the first time the accuracy and feasibility of a wireless, batteryless sensor has been evaluated in a large-scale trial. Using the reduction in sac pressure pulsatility to verify sac exclusion was a very effective strategy in this patient population. Overall, the sensitivity was 0.939 and specificity was 0.800 for detecting type I or III endoleaks. There were five cases of type I or III endoleaks according to intraoperative angiography. Of these, four were successfully detected with the EndoSure sensor (>30% decrease in pulse pressure), and in the remaining case, the sensor showed a significant decrease in the pressure. In this case, the endoleak on the angiogram was a small type I endoleak that showed up on delayed images, and the investigator considered it too insignificant to warrant treatment. This endoleak seemed to be due to an irregular neck and later thrombosed and sealed: a significant pressure decrease was seen during the follow-up, and there was an absence of endoleak and sac enlargement on follow-up CT scan. Although this case was classified as a false-negative result per protocol definitions, the clinical outcome would suggest that the pressure sensor provided more relevant information than the angiogram. During the clinical trial, there were several occasions when real-time pressure sensing was used to determine the specific type of endoleak. In one case, an endoleak that was originally thought to be at the left distal attachment site (type I) was in fact originating from the right side, thus altering the course of treatment for this patient. Although this study was not designed to address this question, it is possible that in the future the use of the sensor during EVAR procedures could reduce the volume of contrast needed to assess the success of stent-graft deployment and allow more precise determination of the type of endoleak. Such quality control during EVAR has been proposed by others using angiographic catheters for pressure measurement.4 As with all new technologies, there was a learning curve associated with learning the appropriate methods of using the sensor, delivery system, and external electronics. This resulted in less-than-optimal sensor positioning or inadequate calibration procedures during some of the initial implantations. This was especially true during the early phase of the trial, when we were using the first-generation system. The manufacturer has since made significant improvements both in the delivery system and in the external electronics, and the system has become much more user friendly. Overall, the system was easy to use, and the optimal techniques for sensor implantation and pressure interrogation could be mastered after the first few procedures. This was proven by the reasonable operating room time and estimated blood loss, both of which were in line with the outcome of the pivotal US endograft studies. We estimate that approximately 10 minutes of procedural time was added to the existing EVAR procedures. In the vast majority of the cases, the interrogation of the sensor was performed within 30 seconds. Patients will be followed up for 5 years, with evaluation at 6 and 12 months and then annually. If a patient requires enhanced follow-up, as defined in the commercially marketed AAA stent-graft labeling, or at the physician’s discretion, more frequent interrogation of the EndoSure sensor may occur. In addition, long-term data will provide information to evaluate the value of the sensor for postoperative follow-up surveillance. Such data will be the focus of a different study and will be reported in a separate article. Conclusions The implantation of the EndoSure wireless pressure was straightforward and safe. The EndoSure sensor measured sac pressure accurately, and pressure sensing was able to detect the type I endoleak equivalent as well as true type I and III endoleaks during EVAR with excellent accuracy. Pressure sensing also confirmed effective exclusion of the sac, and, therefore, intrasac pressure sensing may be a useful adjunct to intraoperative angiography. Author contributions Conception and design: TO, KO, PGS, BK, RW, FC, ED Analysis and interpretation: TO, KO, PGS Data collection: TO, KO, PGS, BK, RW, FC, ED Writing the article: TO Critical revision of the article: TO, KO, PGS, BK, RW, FC, ED Final approval of the article: TO, KO, PGS, BK, RW, FC, ED Statistical analysis: TO Obtained funding: TO Overall responsibility: TO Appendix: APEX Trial Investigators Takao Ohki, MD (Co-Principal Investigator), Kenneth Ouriel, MD (Co-Principal Investigator), David Allie, MD, Arun Chervu, MD, Dan Clair, MD, Frank Criado, MD, Edward Diethrich, MD, Mariano Ferreira, MD, Barry Katzen, MD, Ross Milner, MD, Venketesh Ramaiah, MD, Pierre Galvagni Silveira, MD, Oren Steinmetz, MD, and Rod White, MD. References 1. 1Sanchez LA, Faries PL, Marin ML, Ohki T, Parsons RE, Marty B, et al. Chronic intra-aneurysmal pressure measurement: an experimental method for evaluating the effectiveness of endovascular aortic aneurysm exclusion. J Vasc Surg. 1997;26:222–230. Abstract | Full Text |
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2. 2Marston WA, Criado E, Baird CA. Reduction of aneurysm pressure and wall stress after endovascular repair of abdominal aortic aneurysm in a canine model. Ann Vasc Surg. 1996;10:166–173. Abstract |
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4. 4Treharne GD, Loftus IM, Thompson MM, Lennard N, Smith J, Fishwick G, et al. Quality control during endovascular aneurysm repair: monitoring aneurysmal sac pressure and superficial femoral artery flow velocity. J Endovasc Surg. 1999;6:239–245. MEDLINE |
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6. 6Ellozy SH, Carroccio A, Lookstein RA, Minor ME, Sheahan CM, Juta J, et al. First experience in human beings with a permanently implantable intrasac pressure transducer for monitoring endovascular repair of abdominal aortic aneurysms. J Vasc Surg. 2004;40:405–412. Abstract | Full Text |
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7. 7Ellozy SH, Carroccio A, Lookstein RA, Jacobs TS, Addis MD, Teodorescu VJ, et al. Abdominal aortic aneurysm sac shrinkage after endovascular aneurysm repair: correlation with chronic sac pressure measurement. J Vasc Surg. 2006;43:2–7. Abstract | Full Text |
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a Jikei University School of Medicine, Cleveland Clinic Foundation, Tokyo, Japan b Universidade Federal de Santa Catarina, Cleveland, Ohio c Baptist Cardiac and Vascular Institute, Florinapolis, Brazil d Harbor UCLA Medical Center, Miami, Fla e Union Memorial Hospital, Torrance, Calif f Arizona Heart Institute, Baltimore, Md g Jikei University School of Medicine, Phoenix, Ariz.  Reprint requests: Takao Ohki, MD, PhD, Department of Vascular Surgery, Jikei University School of Medicine, 3-25-8 Nishi-Shinbashi, Minato-ku, Tokyo, Japan 105-8461.
Competition of interest: Drs Ohki, Ouriel, Silveira, Katzen, White, Criado, and Diethrich are members of CardioMEMS scientific advisory board and have been compensated for their time. PII: S0741-5214(06)01843-X doi:10.1016/j.jvs.2006.09.060 © 2007 The Society for Vascular Surgery. Published by Elsevier Inc. All rights reserved. | |
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