UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

SCHEDULE TO

(Amendment No. 1)

TENDER OFFER STATEMENT

UNDER SECTION 14(D)(1) OR SECTION 13(E)(1) OF THE SECURITIES EXCHANGE ACT OF 1934

VNUS MEDICAL TECHNOLOGIES, INC.

(Name Of Subject Company (Issuer))

COVIDIEN GROUP S.A.R.L.

COVIDIEN DELAWARE CORP.

(Names of Filing Persons (Offerors))

Common Stock, par value $0.001 per share

(Title of Class of Securities)

928566108

(CUSIP Number of Common Stock)

Michelangelo Stefani

Covidien Group S.a.r.l.

3b Bld Prince Henri

L-1724, Luxembourg

Telephone: +352 266 379 31

(Name, address and telephone number of person authorized

to receive notices and communications on behalf of filing persons)

with copies to:

Paul Kinsella

Ropes & Gray LLP

One International Place

Boston, Massachusetts 02110

Telephone: (617) 951-7000

CALCULATION OF FILING FEE

Check the appropriate boxes below to designate any transactions to which the statement relates:

Check the following box if the filing is a final amendment reporting the results of the tender offer:   ¨

This Amendment No. 1 to the Tender Offer Statement on Schedule TO (this “Amendment”), filed with the Securities and Exchange Commission on May 28, 2009, amends and supplements the Tender Offer Statement on Schedule TO filed on May 18, 2009 (the “Schedule TO”) and relates to a tender offer by Covidien Delaware Corp., a Delaware corporation (the “Offeror”) and a wholly owned subsidiary of Covidien Group S.a.r.l., a Luxembourg company (“Parent”), to purchase all of the outstanding shares of Common Stock, par value $0.001 per share (the “Shares”), of VNUS Medical Technologies, Inc., a Delaware corporation (the “Company”), at a purchase price of $29.00 per Share, net to the seller in cash, without interest thereon, less any applicable withholding taxes, and subject to the conditions set forth in the Offer to Purchase for Cash dated May 18, 2009 (the “Offer to Purchase”) and in the related Letter of Transmittal (the “Letter of Transmittal” which, together with the Offer to Purchase, as each may be amended and supplemented from time to time, constitute the “Offer”). This Amendment is being filed on behalf of the Offeror and Parent.

The information set forth in the Offer to Purchase and the Letter of Transmittal, copies of which are filed with the Schedule TO as Exhibits (a)(1)(A) and (a)(1)(B), respectively, is incorporated by reference in answers to Items 1 through 9 and Item 11 of the Schedule TO, and is supplemented by the information specifically provided herein.

The Schedule TO is hereby amended and supplemented by adding the following to Sections (a)(2) and (a)(3) of Item 11:

On May 12, 2009, Covidien Ltd., the parent company of Parent and the Offeror, and the Company each filed a Premerger Notification and Report Form with respect to the Offer with the Antitrust Division of the Department of Justice and the Federal Trade Commission (the “FTC”) in accordance with the Hart-Scott-Rodino Antitrust Improvements Act of 1976, as amended (the “HSR Act”).

At 11:59 p.m., New York City time, on May 27, 2009, the HSR Act waiting period with respect to the Offer and Merger expired. Accordingly, the condition to the Offer that any waiting period under the HSR Act shall have expired or been terminated has been satisfied.

SIGNATURES

After due inquiry and to the best of my knowledge and belief, I certify that the information set forth in this statement is true, complete and correct.

EXHIBIT INDEX