ANTITHROMBOTIC THERAPY
CLASS I
(1) After AVR with bileaflet mechanical or Medtronic Hall prostheses, in patients with no risk factors,* warfarin is indicated to achieve an INR of 2.0 to 3.0. If the patient has risk factors, warfarin is indicated to achieve an INR of 2.5 to 3.5.
(2) After AVR with Starr-Edwards valves or mechanical disc valves (other than Medtronic Hall prostheses), in patients with no risk factors,* warfarin is indicated to achieve an INR of 2.5 to 3.5.
(3) After MV replacement with any mechanical valve, warfarin is indicated to achieve an INR of 2.5 to 3.5.
(4) After AVR or MV replacement with a bioprosthesis and no risk factors,* aspirin is indicated at 75 to 100 mg per day.
(5) After AVR with a bioprosthesis and risk factors,* warfarin is indi- cated to achieve an INR of 2.0 to 3.0.
(6) After MV replacement with a bioprosthesis and risk factors,* warfarin is indicated to achieve an INR of 2.0 to 3.0.
(7) For those patients who are unable to take warfarin after MV replacement or AVR, aspirin is indicated in a dose of 75 to 325 mg per day.
(8) The addition of aspirin 75 to 100 mg once daily to therapeutic warfarin is recommended for all patients with mechanical heart valves and those patients with biological valves who have risk factors.
CLASS IIa
(1) During the first 3 months after AVR with a mechanical prosthesis, it is reasonable to give warfarin to achieve an INR of 2.5 to 3.5.
(2) During the first 3 months after AVR or MV replacement with a bioprosthesis, in patients with no risk factors,* it is reasonable to give warfarin to achieve an INR of 2.0 to 3.0.
CLASS IIb
(1) In high-risk patients with prosthetic heart valves in whom aspirin cannot be used, it may be reasonable to give clopidogrel (75 mg per day) or warfarin to achieve an INR of 3.5 to 4.5.
BRIDGING THERAPY IN PATIENTS WITH MECHANICAL VALVES WHO REQUIRE INTERRUPTION OF WARFARIN THERAPY FOR NONCARDIAC SURGERY, INVASIVE PROCEDURES, OR DENTAL CARE
CLASS I
(1) In patients at low risk of thrombosis, defined as those with a bileaflet mechanical AVR with no risk factors,* it is recommended that warfarin be stopped 48 to 72 h before the procedure (so the INR falls to less than 1.5) and restarted within 24 h after the procedure. Heparin is usually unnecessary.
(2) In patients at high risk of thrombosis, defined as those with any mechanical MV replacement or a mechanical AVR with any risk factor, therapeutic doses of intravenous UFH should be started when the INR falls below 2.0 (typically 48 h before surgery), stopped 4 to 6 h before the procedure, restarted as early after surgery as bleeding stability allows, and continued until the INR is again therapeutic with warfarin therapy.
CLASS IIa
(1) It is reasonable to give fresh frozen plasma to patients with mechanical valves who require interruption of warfarin therapy for emergency noncardiac surgery, invasive procedures, or dental care. Fresh frozen plasma is preferable to high-dose vitamin K1.
CLASS IIb
(1) In patients at high risk of thrombosis, therapeutic doses of subcu- taneous UFH (15 000 U every 12 h) or LMWH (100 U per kg every 12 h) may be considered during the period of a subtherapeutic INR.
CLASS III
1. In patients with mechanical valves who require interruption of warfarin therapy for noncardiac surgery, invasive procedures, or dental care, high-dose vitamin K1 should not be given routinely, because this may create a hypercoagulable condition.
THROMBOSIS OF PROSTHETIC HEART VALVES
CLASS I
(1) Transthoracic and Doppler echocardiography is indicated in patients with suspected prosthetic valve thrombosis to assess hemodynamic severity.
(2) Transesophageal echocardiography and/or fluoroscopy is indicated in patients with suspected valve thrombosis to assess valve motion and clot burden.
CLASS IIa
(1) Emergency operation is reasonable for patients with a thrombosed left-sided prosthetic valve and NYHA functional class III–IV symptoms.
(2) Emergency operation is reasonable for patients with a thrombosed left-sided prosthetic valve and a large clot burden.
(3) Fibrinolytic therapy is reasonable for thrombosed right-sided prosthetic heart valves with NYHA functional class III–IV symptoms or a large clot burden.
CLASS IIb
(1) Fibrinolytic therapy may be considered as a first-line therapy for patients with a thrombosed left-sided prosthetic valve, NYHA functional class I–II symptoms, and a small clot burden.
(2) Fibrinolytic therapy may be considered as a first-line therapy for patients with a thrombosed left-sided prosthetic valve, NYHA functional class III–IV symptoms, and a small clot burden if surgery is high risk or not available.
(3) Fibrinolytic therapy may be considered for patients with an ob- structed, thrombosed left-sided prosthetic valve who have NYHA functional class II–IV symptoms and a large clot burden if emergency surgery is high risk or not available.
(4) Intravenous UFH as an alternative to fibrinolytic therapy may be considered for patients with a thrombosed valve who are in NYHA functional class I–II and have a small clot burden.
FOLLOW-UP VISITS
CLASS I
(1) For patients with prosthetic heart valves, a history, physical examination, and appropriate tests should be performed at the first postoperative outpatient evaluation, 2 to 4 weeks after hospital discharge. This should include a transthoracic Doppler echocardiogram if a baseline echocardiogram was not obtained before hospital discharge.
(2) For patients with prosthetic heart valves, routine follow-up visits should be conducted annually, with earlier re-evaluations (with echocardiography) if there is a change in clinical status.
CLASS IIb
1. Patients with bioprosthetic valves may be considered for annual echocardiograms after the first 5 years in the absence of a change in clinical status.
CLASS III
1. Routine annual echocardiograms are not indicated in the absence of a change in clinical status in patients with mechanical heart valves or during the first 5 years after valve replacement with a bioprosthetic valve.
FOLLOW UP VISITS IN PATIENTS WITH COMPLICATIONS
CLASS I
1. Patients with LV systolic dysfunction after valve surgery should receive standard medical therapy for systolic heart failure. This therapy should be continued even if there is improvement of LV dysfunction.
JACC Vol. 52, No. 13, 2008
September 23, 2008: e1-142