Patents Represented by Attorney, Agent or Law Firm Michael J. Chasan
  • Patent number: 6689150
    Abstract: Apparatus for permanent placement across an ostium of a left atrial appendage in a patient, which includes a filtering membrane configured to extend across the ostium of the left atrial appendage. The filtering membrane has a permeable structure which allows blood to flow through but substantially inhibits thrombus from passing therethrough. The apparatus also includes a support structure attached to the filtering membrane which retains the filtering membrane in position across the ostium of the left atrial appendage by permanently engaging a portion of the interior wall of the left atrial appendage. The support structure may be radially expandable from a first configuration to a second configuration which engages the ostium or the interior wall of the left atrial appendage. The filtering membrane may define an opening therethrough that is configured to expand from a first size which inhibits the passage of thrombus therethrough to a second size which allows an interventional device, e.g.
    Type: Grant
    Filed: July 11, 2000
    Date of Patent: February 10, 2004
    Assignee: Atritech, Inc.
    Inventors: Robert A. VanTassel, Robert G. Hauser, Robert Schwartz, David Holmes, Gregg S. Sutton, Thomas E. Borillo, Jeffrey Welch
  • Patent number: 6661253
    Abstract: Enhanced passgate structures for use in low-voltage systems are presented in which the influence of Vt on the range of signals passed by single-transistor passgates is reduced. In one arrangement, the VGATE−Vt limit for signals propagated through NMOS passgates is raised by applying a higher VGATE; in another arrangement, the Vt is lowered. The use of CMOS passgates in applications where single-transistor passgates have traditionally been used is also presented.
    Type: Grant
    Filed: August 16, 2001
    Date of Patent: December 9, 2003
    Assignee: Altera Corporation
    Inventors: Andy L. Lee, Wanli Chang, Cameron McClintock, John E. Turner, Brian D. Johnson, Chiao Kai Hwang, Richard Yen-Hsiang Chang, Richard G. Cliff
  • Patent number: 6652555
    Abstract: A membrane applied to the ostium of an atrial appendage is disclosed. The membrane prevents blood clots in the atrial appendage from escaping therefrom and entering the blood stream which can result in a blocked blood vessel, leading to strokes and heart attacks. The membrane may be permeable or impermeable with respect to blood flow. The membrane is configured to extend over the ostium of the left atrial appendage. The membrane has an outer periphery with a dimension larger than a corresponding dimension of the ostium. Securement means is provided to secure the outer periphery of the membrane in direct engagement with the atrial wall surrounding the ostium. The securement means may located between the membrane and the atrial wall, or the securement means may extend distally from the membrane through the ostium.
    Type: Grant
    Filed: August 18, 2000
    Date of Patent: November 25, 2003
    Assignee: Atritech, Inc.
    Inventors: Robert A. VanTassel, Robert G. Hauser, Robert Schwartz, David Holmes, Gregg S. Sutton, Thomas E. Borillo, Jeffrey Welch
  • Patent number: 6652556
    Abstract: Apparatus for permanent placement across an ostium of a left atrial appendage in a patient, which includes a filtering membrane configured to extend across the ostium of the left atrial appendage. The filtering membrane has a permeable structure which allows blood to flow through but substantially inhibits thrombus from passing therethrough. The apparatus also includes a support structure comprising a plurality of fingers which are radially outwardly expandable with respect to a longitudinal axis to permanently engage the interior wall of the left atrial appendage, wherein the filtering membrane is attached to the support structure extending across the ostium of the left atrial appendage.
    Type: Grant
    Filed: October 26, 2000
    Date of Patent: November 25, 2003
    Assignee: Atritech, Inc.
    Inventors: Robert A. VanTassel, Robert G. Hauser, Robert Schwartz, David Holmes, Gregg S. Sutton, Thomas E. Borillo, Jeffrey Welch