Michael P Brown

University of Florida, Gainesville, Florida, United States

Are you Michael P Brown?

Claim your profile

Publications (4)14.19 Total impact

  • Source
    Thomas S Huber · Michael P Brown · James M Seeger · W Anthony Lee
    [Show abstract] [Hide abstract]
    ABSTRACT: The distal revascularization and interval ligation (DRIL) procedure has evolved as the optimal treatment for access-related hand ischemia despite concerns about its durability. This study was designed to review our institutional experience and objectively define its mid-term outcome. A retrospective review of all patients undergoing the DRIL procedure was performed. The diagnosis of severe hand ischemia was made based primarily upon clinical presentation, but confirmed with noninvasive imaging in select cases. The DRIL conduit was selected based upon noninvasive imaging (vein conduit criteria: saphenous > arm; diameter >/=3 mm) and the proximal anastomosis was positioned >/=7 cm from the access anastomosis. The DRIL bypasses were followed in a graft surveillance protocol and remedial procedures performed as dictated by clinical or ultrasound scan findings. Sixty-four DRIL procedures were performed in 61 patients (age - 58 +/- 13 standard deviation [SD], female - 62%, diabetic - 72%). The index access procedures included: autogenous brachiocephalic - 46%, autogenous brachiobasilic - 31%, autogenous brachioaxillary translocated femoral vein - 20%, other -3%. The precipitating symptoms were pain (25%), paresthesia (34%), motor dysfunction (24%), and tissue loss (17%); a pre-emptive DRIL was performed in 5 patients. The timing of the DRIL relative to the index access was dictated by the symptoms: <24 hrs - 19%; 1 day </= DRIL </=7 days - 29%; 7 days </= DRIL </=30 days - 8%; >30 days - 44%. Perioperative mortality rate was 3% and the complication rate was 22% (wound - 14%). The DRIL procedure relieved the ischemic symptoms in 78% of the cases (residual symptoms: paresthesia - 13%; pain - 5%; tissue loss - 4%; motor - 2%). The DRIL also resulted in significant (P < .05) increases in both the wrist/brachial index (WBI) and digital/brachial index (DBI) with the mean increases of 0.34 +/- 0.26 and 0.41 +/- 0.21, respectively. The primary DRIL patency rates (+/- standard error of the mean [SEM]) were 77 +/- 8%, 74 +/- 9%, and 71 +/- 9% at 1 year, 3 years, and 5 years, respectively, while the corresponding secondary patency rates were 81 +/- 7%, 76 +/- 9%, and 76 +/- 9%, and the survival rates were 71 +/- 6%, 59 +/- 7%, and 33 +/- 9%. The index access procedure went on to mature sufficiently for cannulation in 68% of the cases when the DRIL was performed early (ie, <3 months from index access); all accesses functional at the time of the DRIL were used for dialysis throughout the perioperative period. The DRIL procedure safely and effectively relieves the symptoms of severe access-related hand ischemia while preserving the access. The midterm results suggest that the DRIL bypasses are durable, although long-term graft surveillance may be justified given the observed failures.
    Preview · Article · Oct 2008 · Journal of vascular surgery: official publication, the Society for Vascular Surgery [and] International Society for Cardiovascular Surgery, North American Chapter
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Percutaneous access during endovascular aortic repair has been shown to be feasible and safe using a suture-mediated closure device ("Preclose" technique) for closure of up to 24F introducer sheaths. The purpose of this study is to examine the late outcomes of those femoral arteries repaired in this manner. The Preclose technique has been previously described. Briefly, the technique involves two Perclose Proglide devices deployed in the femoral artery prior to insertion of the large diameter introducer sheath and then closure of the arteriotomy by tying down knots of the Proglide following removal of the sheath. The medical records of all patients who underwent endovascular aortic repairs using the Preclose technique between December 2004 and August 2007 were reviewed. Follow-up protocol consisted of computed tomography (CT) angiograms performed at 1, 6, and 12 months, and annually thereafter. All Preclose patients who had at least a 6-month postoperative scan were included in the study. For each patient, the most recent postoperative scan was compared with the preoperative scan for evidence of any new anatomic abnormalities of the femoral artery such as dissection, stenosis, or pseudoaneurysm. Three-dimensional post processing with multiplanar reconstructions was also performed as necessary to confirm axial scan findings. A total of 292 patients underwent percutaneous endovascular aortic repairs (TEVAR-125, EVAR-167). Four hundred thirty-two femoral arteries were closed with 870 devices. Four hundred eighteen vessels were approximated with two devices, while 30 arteries required three devices for hemostasis and an additional four vessels only required a single device. Two hundred seventy-eight (64.3%) vessels were accessed with sheaths 18 to 24F. Four hundred eight femoral arteries (94.4%) were closed successfully with the Preclose technique. There were 100 patients (TEVAR-35, EVAR-65) who had adequate postoperative CT scan at 6-months or later. The mean follow up was 11.6 +/- 5.0 months. Of the 156 femoral arteries in these 100 patients repaired using the Preclose technique, there were 3 late complications in 3 patients, 1 asymptomatic femoral artery dissection, and 2 femoral artery pseudoaneurysms requiring surgical repair, resulting in a late complication rate of 1.92% (3/156). Percutaneous closure of femoral arteries after large diameter introducer sheaths using the Preclose technique has a low incidence of early and late complications related to the closure site.
    Preview · Article · Jun 2008 · Journal of Vascular Surgery
  • [Show abstract] [Hide abstract]
    ABSTRACT: The morbidity and mortality rates associated with open thoracoabdominal aortic aneurysm (TAAA) repair are substantial. This study was designed to review our early experience with the hybrid endovascular and, or open approach for TAAA repair. Patients undergoing elective hybrid repair of their TAAAs were retrospectively reviewed. Seventeen patients (mean age 69+/-15 years, male, 76%) underwent visceral and renal revascularization as the first stage of their hybrid repair. The Crawford extent included: II, 2; III, 8; and IV, 7. Perioperative mortality and complication rates after the first stage were 24% and 25%, respectively; the mean intensive care unit stay and total length of stay were 7+/-12 days (range 1 to 45 days) and 22+/-33 days (range 3 to 100 days), respectively. The endovascular aneurysm repair or second stage procedure was performed in 12 of 13 (92%) of the surviving patients, with a mean of 27+/-27 days (range 6 to 99 days) between the procedures. Two patients experienced intraoperative complications during the second stage, but there were no deaths or additional postoperative complications. Patients did not require the intensive care unit, and the overall mean length of stay after the second stage was 2+/-2 days (range 1 to 5 days). The mean postoperative followup among the 11 patients completing both stages was 8+/-12 months (range 1 to 15 months). The primary patency rate for the visceral and renal bypasses was 96% (54 of 56). The hybrid approach for patients with TAAAs may reduce complications in the average, low-risk patient and may extend the indications for repair to patients considered higher risk based on age, comorbidities, or anatomic considerations.
    No preview · Article · Oct 2007 · Journal of the American College of Surgeons
  • Source
    W Anthony Lee · Michael P Brown · Peter R Nelson · Thomas S Huber
    [Show abstract] [Hide abstract]
    ABSTRACT: Percutaneous access during endovascular aneurysm repair has been difficult owing to the large size of the delivery catheters. This study reports a single-center experience of totally percutaneous access during endovascular abdominal and thoracic aortic repairs using the Preclose Proglide device (Abbott Vascular, Redwood City, Calif). Between December 2004 and August 2006, 262 endovascular aortic aneurysm repairs were performed. Percutaneous access was used for the introduction of 12F to 24F sheaths (4.4-mm to 8.6-mm outer diameter). The technique involved deployment of two Proglide devices before insertion of the sheath ("Preclose" technique) with the sutures left extracorporeally for closure after conclusion of the procedure. A prospectively maintained endovascular database and medical records were retrospectively reviewed. Rates of technical success, failure modes, and the overall duration of the endovascular repair compared with a similar cohort using open femoral exposures were examined. A total of 559 Proglide devices were used to close 279 femoral arteries, and 175 (63%) required the insertion of 18F to 24F sheaths. There were 16 failures, mainly due to obesity, device malfunction, severe calcific disease, and faulty arterial punctures, for a technical success rate of 94.3%. The success rates for 12F to 16F size sheaths were significantly higher than for the larger 18F to 24F sheaths (99.0% vs 91.4%, P<.01). For both endovascular abdominal (EVAR) and thoracic (TEVAR) aortic repairs, the Preclose technique resulted in shorter overall procedure times compared with a similar cohort in which open femoral exposures were used (EVAR, 115 vs 128 min, P<.001; TEVAR, 80 vs 112, P=.019). Despite this reduction of procedure time, the savings on the cost of operating room time was negated by the cost of the Proglide devices ($295 per device). Percutaneous access for endovascular aortic repair is safe and feasible using the Proglide device. Although the success rates are higher for smaller size sheaths, successful closures may be obtained for up to 24F sheaths. Percutaneous access may result in shorter overall procedure times and potentially lower operating room costs, but this appears to be offset by the cost of the closure devices.
    Full-text · Article · Jun 2007 · Journal of Vascular Surgery