Aortic Valve Disease
Clinical Snapshot
Aortic valve disease means two distinct diseases. Aortic stenosis (AS) is a fixed, mechanical outflow obstruction — the valve area becomes too small to eject blood without a large pressure gradient, producing concentric LV hypertrophy. Aortic regurgitation (AR) is a leaking valve that lets blood flow backward into the left ventricle during diastole, producing chronic volume overload and eccentric LV dilation. Calcific (degenerative) AS in an aging population is now the most common clinically significant valve disease encountered in practice, followed by bicuspid-valve disease in younger adults; AR is less common overall but follows an entirely different, and in its acute form immediately life-threatening, management logic.[1]
The single most important teaching point for both conditions: no drug therapy changes the natural history of the diseased valve itself — nothing slows AS progression, and nothing reverses AR. Pharmacotherapy in this chapter treats concomitant hypertension, bridges a patient to a procedure, or manages left ventricular dysfunction once it develops; it is never a substitute for correctly timed aortic valve replacement or repair. Acute severe AR is a surgical emergency, managed on an entirely different and much faster timeline than the chronic valve diseases covered elsewhere in this chapter.
Recognize the Condition
Aortic stenosis
Often silent for years — a fixed obstruction only produces symptoms once the valve area has narrowed substantially.
Symptoms — the classic triad
- Exertional dyspnea — usually the earliest symptom.
- Exertional angina — even without obstructive coronary disease, from a mismatch between hypertrophied myocardial oxygen demand and fixed coronary supply.
- Exertional syncope or presyncope — from an inability to augment cardiac output against the fixed obstruction during exertional vasodilation.
Signs
- A harsh, crescendo-decrescendo (diamond-shaped) systolic ejection murmur, loudest at the right upper sternal border, radiating to the carotids.
- A diminished and delayed carotid upstroke (pulsus parvus et tardus).
- A soft or absent second heart sound (A2), reflecting a poorly mobile, calcified valve.
- A sustained, non-displaced apical impulse and a fourth heart sound (S4), reflecting concentric LV hypertrophy rather than dilation.
Aortic regurgitation — chronic vs. acute
The same underlying lesion produces two completely different clinical pictures depending on how much time the heart has had to compensate.
Chronic AR — often asymptomatic for years
The left ventricle dilates gradually to accommodate the regurgitant volume, so patients can remain asymptomatic long after regurgitation becomes severe. Eventual symptoms are exertional dyspnea, fatigue, and palpitations as compensation fails. Signs: an early, high-pitched decrescendo diastolic murmur at the left (or right, with aortic root dilation) sternal border; a widened pulse pressure with bounding, collapsing peripheral pulses; a displaced, hyperdynamic apical impulse. Numerous eponymous peripheral signs (Corrigan's water-hammer pulse, de Musset's head bobbing, Quincke's nail-bed pulsation, Duroziez's femoral murmur) are classic teaching findings but add little once echocardiography is available.
Acute AR — a surgical emergency
The left ventricle has had no time to dilate and compensate, so even a moderate regurgitant volume causes a rapid, severe rise in LV filling pressure — presenting as sudden pulmonary edema, tachycardia, and cardiogenic shock. The diastolic murmur is often soft or inaudible because LV and aortic diastolic pressures equalize quickly — do not use a quiet or absent murmur to rule out severe acute AR in a patient with a plausible cause (endocarditis, aortic dissection, chest trauma). Pulse pressure is typically normal or only mildly widened, unlike the classic wide pulse pressure of chronic AR, because there has been no time for the compensatory changes that produce it.
Risk Factors
Risk factors for aortic stenosis
- Age — calcific/degenerative AS is primarily a disease of aging.
- Bicuspid aortic valve — the leading cause of AS presenting before age 65.
- Chronic kidney disease and hemodialysis — accelerated valvular calcification.
- The same cardiovascular risk factors associated with atherosclerosis — hypertension, dyslipidemia, smoking, diabetes, obesity — even though, unlike atherosclerosis, treating these risk factors has not been shown to slow AS progression itself (see Choose Initial Treatment).
- Prior chest/mediastinal radiation therapy.
- Rheumatic heart disease — now an uncommon cause of isolated AS in Canada, but still relevant in patients who immigrated from regions where rheumatic fever remains common.
- A family history of bicuspid aortic valve or early valve disease.
Risk factors for aortic regurgitation
- Bicuspid aortic valve.
- Infective endocarditis, native or prosthetic valve — can cause acute, severe AR through leaflet destruction or perforation.
- Aortic root or ascending aortic disease — Marfan syndrome and other connective tissue disorders, bicuspid-valve-associated aortopathy, chronic hypertension, annuloaortic ectasia, and age-related aortic dilation.
- Acute aortic dissection involving the aortic root — can cause acute, severe AR.
- Chest trauma.
- Rheumatic heart disease.
- A prior aortic valve intervention (surgical or transcatheter) with a paravalvular leak, or structural bioprosthetic valve deterioration over time.
- Certain drugs associated with valvulopathy (e.g., ergot-derived dopamine agonists, some historical anorectic agents) — uncommon but worth a medication review in unexplained AR.
Red Flags & Refer
The following need urgent — same-day or emergency — assessment, not a routine follow-up visit:
- Suspected acute severe AR — sudden dyspnea, pulmonary edema, or cardiogenic shock in a patient with endocarditis, a possible aortic dissection, or recent chest trauma. This is a surgical emergency; a soft or absent diastolic murmur does not rule it out.
- New symptoms in known or suspected severe AS — exertional dyspnea, angina, or syncope/presyncope in a patient with a systolic ejection murmur or a known diagnosis of AS. Symptomatic severe AS carries a very high risk of death without timely intervention — this is a prompt for urgent cardiology referral, not a trial of additional medical therapy.
- Syncope or presyncope with a systolic ejection murmur — treat as possible severe AS until proven otherwise; avoid vasodilators, high-dose diuretics, or other agents that could precipitate hypotension in a fixed-obstruction physiology while awaiting assessment.
- A new murmur with fever, or any other finding suggesting infective endocarditis — assess per the Infective Endocarditis chapter.
- New or worsening heart failure signs in a patient with known AS or AR — pulmonary edema, rising JVP, or rapid weight gain.
- Suspected aortic dissection (tearing chest/back pain, pulse or blood pressure asymmetry between limbs) with a new diastolic murmur — treat as a vascular and valvular emergency simultaneously.
Assessment & Diagnosis
History
- Exertional symptoms specifically — dyspnea, angina, syncope/presyncope — and how they have changed over time; a patient may unconsciously self-limit activity to avoid triggering symptoms, masking true functional status.
- Known cardiac history — a childhood murmur, rheumatic fever, prior cardiac surgery or valve intervention, or a family history of bicuspid aortic valve or early valve disease.
- Risk factors for endocarditis or aortic dissection when an acute presentation is possible.
Physical examination
Murmur timing, location, and radiation (see Recognize the Condition), carotid upstroke, pulse pressure and peripheral pulse character, and signs of heart failure or hemodynamic instability.
Echocardiography — the primary diagnostic tool
Transthoracic echocardiography (TTE) is the first-line test for any suspected valve disease — it grades severity, measures LV size and function, and screens for other structural abnormalities (e.g., aortic root dilation, bicuspid morphology). Transesophageal echocardiography (TEE) is used when TTE windows are inadequate, when a prosthetic valve needs closer evaluation, or when endocarditis is suspected.[1]
Aortic stenosis severity grading
| Severity | Peak jet velocity (Vmax) | Mean gradient | Aortic valve area |
|---|---|---|---|
| Mild | 2.6-2.9 m/s | Under 20 mmHg | Over 1.5 cm² |
| Moderate | 3.0-3.9 m/s | 20-39 mmHg | 1.0-1.5 cm² |
| Severe | 4.0 m/s or more | 40 mmHg or more | Under 1.0 cm² (indexed under 0.6 cm²/m²) |
| Very severe | 5.0 m/s or more | 60 mmHg or more | — |
Discordant results — a small valve area with only a moderate gradient — usually reflect a low-flow, low-gradient state rather than genuinely mild-to-moderate disease, and need further workup rather than being taken at face value.[1]
Low-flow, low-gradient aortic stenosis
- Classical (reduced-EF) low-flow, low-gradient AS — LVEF under 50% with a low stroke volume index. Dobutamine stress echocardiography distinguishes true-severe AS (valve area stays 1.0 cm² or less and the gradient rises to 40 mmHg or more as flow is augmented) from pseudo-severe AS (the valve area increases above 1.0 cm² with augmented flow, meaning the stenosis was overestimated at baseline low flow). Absent contractile/flow reserve on this test is itself a poor prognostic sign.
- Paradoxical low-flow, low-gradient AS — a preserved EF (50% or more) but a small, hypertrophied, restrictive LV with a low stroke volume index despite the normal ejection fraction — typically an older patient, often a woman, with longstanding hypertension. Aortic valve calcium scoring on CT helps confirm true severe AS when echo findings are discordant: a score of 2000 Agatston units or more in men, or 1200 or more in women, makes severe AS likely.[1]
Aortic regurgitation severity grading
Multiple semiquantitative and quantitative echo parameters are combined rather than relying on any single number — jet width relative to the LV outflow tract, vena contracta width, regurgitant volume and fraction, pressure half-time, and holodiastolic flow reversal in the descending aorta all support a severe-AR classification when concordant.[2]
| Severity | Vena contracta width | Regurgitant fraction | Supporting qualitative findings |
|---|---|---|---|
| Mild | Under 0.3 cm | Under 30% | Narrow, brief regurgitant jet |
| Moderate | 0.3-0.6 cm | 30-49% | Intermediate findings — insufficient on their own to classify severity |
| Severe | Over 0.6 cm | 50% or more | Dense, wide central jet; holodiastolic flow reversal in the descending aorta |
Once severe AR is confirmed, LV size and function become the key parameters to track over time — LV end-systolic and end-diastolic dimensions (and their body-surface-area-indexed values) and LVEF directly determine surgical timing (see Choose Initial Treatment).[1]
Bicuspid aortic valve
Refer first-degree relatives of a patient with a bicuspid aortic valve for an echocardiogram, given its heritable component, and arrange periodic aortic root/ascending aorta imaging in the patient themselves — bicuspid-valve-associated aortopathy carries its own aneurysm and dissection risk independent of the valve lesion.
Treatment Targets
- For AS: recognize the transition to severe, symptomatic disease promptly and refer for timely valve replacement — there is no pharmacologic target to reach, since no drug alters the valve's natural history.[3]
- For AR: control blood pressure/afterload where it genuinely helps (see Choose Initial Treatment), track LV size and function over time, and refer for surgery before irreversible LV dysfunction develops.
- Recognize and manage acute severe AR as a surgical emergency, not a medical-therapy problem.
- Select and maintain the correct antithrombotic regimen for any prosthetic valve or valve repair, matched specifically to valve type (mechanical vs. bioprosthetic) and position.
- Prevent infective endocarditis in patients who meet the specific high-risk criteria — see the Infective Endocarditis chapter for the full prophylaxis regimen and eligibility list, which applies unchanged to a prosthetic aortic valve and to valve repair material.
- Once LV systolic dysfunction (reduced LVEF) develops from either AS or AR, apply standard heart failure pharmacotherapy — see the Heart Failure chapter for the complete 4-pillar GDMT approach.
Choose Initial Treatment
No drug therapy slows the progression of aortic stenosis. Statins were once hypothesized to reduce the atherosclerosis-like calcific process, but the randomized SEAS trial found no effect of intensive lipid-lowering therapy on the course of aortic-valve stenosis, despite reducing ischemic cardiovascular events for other reasons — do not start or continue a statin with an expectation that it will slow AS progression, and correct this misconception when it comes up.[3] Manage hypertension, dyslipidemia, and other cardiovascular risk factors for their own independent cardiovascular benefit, never as AS-directed therapy.
Symptomatic severe AS refer urgently for aortic valve replacement — transcatheter (TAVI) or surgical (SAVR), decided by a multidisciplinary heart team based on age, surgical risk, valve/vascular anatomy, frailty, and patient preference, not by a surgical-risk score alone.[4] Symptomatic severe AS carries a very high risk of death without intervention — there is no role for prolonged medical management while deferring referral.
Asymptomatic severe AS most patients are followed with serial monitoring (see Monitoring & Follow-Up) rather than intervening immediately. Consider earlier intervention when any of the following is present: LVEF under 50%, very severe AS (peak velocity 5.0 m/s or more), a fall in systolic blood pressure with exercise or an otherwise markedly abnormal exercise test, rapid hemodynamic progression, or a markedly elevated BNP without another explanation.[1]
Low-flow, low-gradient AS confirm true severe AS first (dobutamine stress echocardiography for reduced EF, or aortic valve calcium scoring for paradoxical low-flow, low-gradient AS — see Assessment & Diagnosis) before committing to intervention.
Caution — vasodilators and negative inotropes in severe AS the fixed valvular obstruction limits the heart's ability to increase cardiac output to compensate for a drop in systemic vascular resistance or contractility. Use vasodilators (including an ACE inhibitor/ARB given for unrelated hypertension), aggressive diuresis, and a non-dihydropyridine calcium channel blocker cautiously in a patient with severe AS, since they can precipitate significant hypotension.
Surgical emergency arrange emergent cardiac surgical referral immediately — do not attempt to fully stabilize medically before involving surgery. While arrangements are underway, an IV vasodilator (sodium nitroprusside) with or without an inotrope (dobutamine) can be used as a hemodynamic bridge to reduce afterload and support forward flow.
Do not use a beta-blocker — the compensatory tachycardia is what maintains forward cardiac output in a ventricle that has had no time to dilate, and slowing the heart rate lengthens diastole, worsening the regurgitant volume. Do not place an intra-aortic balloon pump — counterpulsation augments diastolic aortic pressure and directly worsens the regurgitant fraction.
Asymptomatic, normal LV size/function routine monitoring (see Monitoring & Follow-Up); treat hypertension if present, targeting a systolic blood pressure under 140 mmHg, since sustained afterload also increases the regurgitant volume.
Vasodilator therapy as a bridge an ACE inhibitor, ARB, or dihydropyridine calcium channel blocker (e.g., nifedipine) can be used specifically in a patient with symptomatic severe AR who is not currently a candidate for surgery, to reduce afterload and regurgitant volume, and to control concurrent hypertension when present. Vasodilator therapy has not been shown to delay the need for surgery in an asymptomatic, normotensive patient with preserved LV function, and must not be used as a substitute for timely surgical referral once a surgical indication is met.[2]
Surgical indication met refer for aortic valve surgery (repair when anatomically feasible, or replacement) for symptomatic severe AR regardless of LV function, or for asymptomatic severe AR with LV systolic dysfunction (LVEF 55% or less) or severe LV dilation (LV end-systolic dimension over 50 mm, or indexed over 25 mm/m²).[1]
Non-Pharmacologic Treatment
- Definitive treatment of clinically significant AS or AR is procedural, not pharmacologic — surgical or transcatheter valve replacement (or, for AR, valve-sparing repair when feasible) decided by a multidisciplinary heart team.[4]
- Discuss TAVI versus SAVR based on age, surgical risk, frailty, valve and vascular anatomy, and patient preference — a lower age and longer life expectancy generally favours SAVR, while advanced age (over 80) or a high/prohibitive surgical risk generally favours transfemoral TAVI; patients in between are managed through shared decision-making incorporating both options.[4]
- Refer first-degree relatives of a bicuspid aortic valve patient for echocardiographic screening, and arrange periodic surveillance imaging of the aortic root/ascending aorta in the patient.
- Reinforce good dental hygiene and regular dental care, especially before elective valve intervention — see the Infective Endocarditis chapter for the specific high-risk conditions (which include a prosthetic aortic valve) that warrant antibiotic prophylaxis before a qualifying dental procedure.
- Manage cardiovascular risk factors — smoking cessation, blood pressure, lipids, glucose, weight — for their own cardiovascular benefit, not with any expectation of slowing AS progression.
- Individualize exercise recommendations: low-to-moderate intensity activity is generally appropriate in asymptomatic mild-to-moderate valve disease; avoid high-intensity or competitive static/isometric exercise in severe AS given the syncope and sudden-death risk, and reassess exercise tolerance objectively (formal exercise testing) rather than relying on self-reported activity level, which is often unconsciously self-limited.
- Recommend routine influenza and pneumococcal vaccination as part of general cardiac preventive care.
Special Populations
Pregnancy
Severe AS is poorly tolerated in pregnancy — the fixed valvular obstruction limits the ability to increase cardiac output to meet the demands of pregnancy, and hemodynamic decompensation can occur at any point in gestation or delivery. Arrange pre-conception counselling and, where possible, correct severe symptomatic (or even severe asymptomatic, per specialist assessment) AS before conception rather than during pregnancy. Chronic AR is generally better tolerated in pregnancy, since the physiologic fall in systemic vascular resistance reduces the regurgitant volume, but still requires monitoring through pregnancy and the postpartum period by a combined cardio-obstetric team. If a vasodilator is needed for AR-associated hypertension in pregnancy, avoid ACE inhibitors and ARBs (teratogenic) — a dihydropyridine calcium channel blocker or methyldopa/labetalol (see the Hypertension chapter) are the appropriate alternatives. For a patient with a mechanical prosthetic valve, warfarin's teratogenicity (particularly in the first trimester) must be weighed against the materially higher valve-thrombosis risk of alternative regimens in pregnancy — this is a multidisciplinary, individualized decision, not a default switch to heparin; see the Atrial Fibrillation chapter for the general principles of anticoagulant selection in pregnancy.
Breastfeeding
Warfarin is compatible with breastfeeding. An ACE inhibitor with strong breastfeeding safety data (e.g., enalapril, ramipril) can be used when a vasodilator is genuinely needed. DOAC data in lactation remain limited — this does not create any new exception to their contraindication in a mechanical valve.
Older adults
Advanced age or frailty is not, on its own, a reason to withhold aortic valve intervention in symptomatic severe AS — it is instead a factor that shifts the heart team's choice toward transfemoral TAVI over SAVR, since TAVI is generally preferred over SAVR in patients over 80 years of age or with a high or prohibitive surgical risk.[4] Older adults are also more susceptible to hypotension from vasodilator or diuretic therapy in the setting of severe AS — titrate more cautiously and monitor more closely.
Renal impairment / chronic kidney disease
CKD and dialysis-dependent kidney disease accelerate valvular calcification and are independently associated with faster AS progression and worse outcomes. Pre-procedural CT angiography for TAVI planning involves iodinated contrast — plan renal-protective measures and coordinate timing with the interventional team in a patient with reduced eGFR. Adjust ACE inhibitor/ARB dosing and monitoring for renal function as for any other indication.
Bicuspid aortic valve and associated aortopathy
Refer first-degree relatives for echocardiographic screening given the heritable component, and arrange periodic imaging of the aortic root and ascending aorta in the patient — the aneurysm and dissection risk associated with bicuspid-valve aortopathy is managed on its own surveillance schedule, independent of the valve lesion itself.
Pediatrics
Congenital and pediatric aortic valve disease (including pediatric-onset bicuspid valve disease and congenital AS) is managed by pediatric cardiology using dedicated pediatric protocols and does not follow the adult severity thresholds or intervention criteria in this chapter.
Monitoring & Follow-Up
- Echocardiographic surveillance by AS severity: mild — every 3-5 years; moderate — every 1-2 years; asymptomatic severe — every 6-12 months; very severe or rapidly progressive — every 3-6 months. Reassess promptly, out of cycle, for any new symptom rather than waiting for the next scheduled echo.
- Echocardiographic surveillance by AR severity: mild — every 3-5 years; moderate — every 1-2 years; severe with normal LV size/function — every 6-12 months, tracking LV end-systolic/end-diastolic dimensions and LVEF specifically, since these values (not symptoms alone) trigger surgical referral in asymptomatic severe AR.
- Reassess symptoms and functional status at every visit, regardless of the scheduled echo interval — new exertional dyspnea, angina, or syncope/presyncope warrants prompt reassessment, not deferral to the next routine appointment.
- After TAVI or SAVR: echocardiogram at discharge, 30 days, and 1 year, then annually — watch for paravalvular leak, prosthesis-patient mismatch, and (for a bioprosthetic valve) structural valve deterioration, which typically becomes clinically relevant after roughly 10-15 years.
- For warfarin in a mechanical valve: INR every 4-12 weeks once stable, more often if labile; point-of-care/self-testing is a reasonable option where available (see the Atrial Fibrillation chapter for the general principles of INR monitoring).
- Do not interrupt warfarin in a patient with a mechanical heart valve for a minor procedure — cataract surgery, routine dental procedures, and skin biopsy do not require holding anticoagulation.[6]
- Monitor blood pressure at every visit in a patient on vasodilator therapy for AR, and reassess renal function/potassium if an ACE inhibitor or ARB is used.
- Once heart failure pharmacotherapy is started for LV dysfunction arising from AS or AR, follow the monitoring schedule in the Heart Failure chapter.
Common Errors to Avoid
- Prescribing or continuing a statin specifically to slow AS progression — the SEAS trial found no effect on the course of aortic-valve stenosis.[3]
- Using any DOAC (apixaban, dabigatran, edoxaban, or rivaroxaban) in a patient with a mechanical heart valve, including for an unrelated indication like atrial fibrillation — this is contraindicated regardless of AF status.[5]
- Assuming a bioprosthetic valve carries the same DOAC restriction as a mechanical valve — it does not; a DOAC is appropriate for AF in a patient with a bioprosthetic valve once the early post-implantation window has passed.
- Giving a vasodilator, an aggressive diuretic, or a non-dihydropyridine calcium channel blocker to a patient with severe AS without recognizing the fixed-obstruction physiology — this can precipitate significant hypotension.
- Using a beta-blocker, or placing an intra-aortic balloon pump, in acute severe aortic regurgitation — both worsen the physiology rather than helping it.
- Ruling out acute severe AR because the diastolic murmur is soft or inaudible — rapid pressure equalization in the unprepared left ventricle often makes the murmur quiet.
- Delaying cardiology referral for symptomatic severe AS to try additional medical therapy first — no medical therapy substitutes for timely valve replacement once symptoms develop.
- Interrupting warfarin for a mechanical heart valve for a minor procedure (cataract surgery, routine dental work, skin biopsy) — this is not recommended and increases valve-thrombosis risk without a meaningful bleeding benefit.
- Missing family screening for a bicuspid aortic valve patient's first-degree relatives, and missing surveillance imaging of the aortic root/ascending aorta in the patient.
- Treating vasodilator therapy for chronic AR as a way to delay surgical referral once a genuine surgical indication (symptoms, LV dysfunction, or severe LV dilation) has been met.
Clinical Decision Algorithm
Drug Tables
How to use this table: Doses are adult doses and require patient-specific confirmation, including renal/hepatic adjustment. Select any drug name to open its complete Pharmasist Drug Database page.
Vasodilator therapy — chronic aortic regurgitation
For a symptomatic severe-AR patient not currently a surgical candidate, or to treat concurrent hypertension (target systolic BP under 140 mmHg). Not shown to delay the need for surgery in an asymptomatic, normotensive patient with preserved LV function.
| Drug | Dose | Adverse effects | Interactions | Comments |
|---|---|---|---|---|
| Ramipril | Initial 1.25-2.5 mg PO daily, titrate as tolerated | Hypotension, hyperkalemia, dry cough, renal insufficiency | Hyperkalemia with potassium-sparing diuretics/ARBs/potassium supplements; renal risk with NSAIDs | Avoid in pregnancy. |
| Losartan | Initial 25-50 mg PO daily, titrate as tolerated | Hypotension, hyperkalemia, renal insufficiency | Same class interactions as ramipril | ARB alternative if ACE-inhibitor cough develops. Avoid in pregnancy. |
| Nifedipine (extended-release) | 30-90 mg PO once daily | Peripheral edema, headache, flushing | Increased levels with strong CYP3A4 inhibitors | Dihydropyridine CCB alternative — afterload reduction without negative inotropy. |
Emergency medical bridge — acute severe aortic regurgitation
A bridge to emergent surgery only, never a substitute for it. Do not use a beta-blocker or an intra-aortic balloon pump in this setting (see Choose Initial Treatment).
| Drug | Dose | Adverse effects | Interactions | Comments |
|---|---|---|---|---|
| Sodium nitroprusside | IV infusion, titrated to blood pressure response — specialist/critical-care-directed | Hypotension; cyanide/thiocyanate toxicity with prolonged high-dose use | Additive hypotension with other vasodilators | Reduces afterload and regurgitant volume while surgery is arranged. |
| Dobutamine | IV infusion, titrated to hemodynamic response — specialist/critical-care-directed | Tachyarrhythmia, increased myocardial oxygen demand | Additive arrhythmia risk with other sympathomimetics | Supports forward flow in a hypoperfused patient while surgery is arranged. |
Antithrombotic therapy by prosthetic valve type
The central safety point for any mechanical valve, in any position, for any indication: warfarin is mandatory and DOACs are contraindicated.[5] Regimens differ meaningfully for a bioprosthetic valve, a transcatheter valve, and after valve repair.[6]
| Valve type / clinical scenario | Recommended antithrombotic therapy | INR target (if warfarin) | Key teaching point |
|---|---|---|---|
| Mechanical aortic valve (bileaflet or tilting-disc), no additional risk factors | Warfarin; add ASA 81 mg daily if low bleeding risk | 2.5 (range 2.0-3.0) | DOACs are contraindicated regardless of AF status. |
| Mechanical aortic valve with additional risk factors (AF, prior thromboembolism, LV dysfunction, hypercoagulable state) or an older-generation design | Warfarin ± ASA 81 mg daily | 3.0 (range 2.5-3.5) | Same DOAC prohibition applies. |
| On-X bileaflet mechanical aortic valve, 3 or more months post-implant, no AF/additional risk factors | Warfarin + ASA 81 mg daily | 1.5-2.0 (lower intensity) | Specific to the On-X design only — do not extrapolate to other mechanical valves. AHA guidance considers this reasonable; ESC guidance does not endorse it. |
| Mechanical mitral valve (any design) | Warfarin ± ASA 81 mg daily | 3.0 (range 2.5-3.5) | The mitral position is more thrombogenic than aortic — DOACs remain contraindicated. |
| Bioprosthetic aortic or mitral valve, sinus rhythm, no other anticoagulation indication | Warfarin for 3-6 months, or ASA 81 mg daily | 2.5, if warfarin is used | Long-term ASA 81 mg daily once the initial window has passed. |
| Bioprosthetic tricuspid or pulmonic valve | Warfarin for 3 months, or ASA 81 mg daily | 2.5, if warfarin is used | Lower thromboembolic risk than a left-sided bioprosthesis. |
| Bioprosthetic valve + atrial fibrillation | Standard nonvalvular-AF anticoagulation applies | — | This is not "valvular AF" — a DOAC is appropriate long-term. Warfarin is generally continued for the first 3 months post-implantation. See the Atrial Fibrillation chapter. |
| TAVI, no other anticoagulation indication | Single antiplatelet — ASA 81 mg daily | — | Routine dual antiplatelet or anticoagulant therapy is no longer recommended — it increases bleeding without reducing thrombotic events. |
| TAVI + atrial fibrillation | Oral anticoagulant alone, per standard AF guidance | — | Do not add an antiplatelet — the combination increases bleeding without added benefit. |
| Surgical aortic valve repair | ASA alone, for at least 3 months | — | |
| Surgical mitral or tricuspid valve repair | ASA or warfarin (mitral) for 3 months; warfarin (tricuspid) for 3 months | 2.5, if warfarin is used |
Anticoagulant and antiplatelet agents
Match the correct regimen to the specific valve type using the table above. See the Atrial Fibrillation chapter for complete DOAC dosing/monitoring where a DOAC is genuinely appropriate — a bioprosthetic valve or TAVI plus AF, beyond the early post-implantation window.
| Drug | Dose | Adverse effects | Interactions | Comments |
|---|---|---|---|---|
| Warfarin | Individualized, titrated to the valve-specific INR target above | Bleeding, rare skin necrosis, teratogenic | Extensive — CYP2C9/VKORC1-mediated interactions with innumerable drugs, foods, and herbal products | Do not interrupt for a minor procedure — cataract surgery, routine dental work, or a skin biopsy do not require holding it.[6] |
| Acetylsalicylic acid (ASA) | 81 mg PO once daily | GI upset, bleeding | Additive bleeding risk with warfarin/DOACs/NSAIDs | Role and dose depend on valve type — see the table above. |
| Apixaban | Not used for a mechanical valve, at any dose | Bleeding, bruising | Not applicable to this indication | Representative DOAC — the mechanical-valve contraindication applies equally to dabigatran, edoxaban, and rivaroxaban.[5] |
Endocarditis prophylaxis — prosthetic aortic valve, dental procedures
For the specific high-risk cardiac conditions and qualifying dental procedures defined in the Infective Endocarditis chapter only — a prosthetic aortic valve (including a transcatheter-implanted valve) is one of them. See that chapter for the complete regimen, timing, and penicillin-allergy alternatives.
| Drug | Dose | Adverse effects | Interactions | Comments |
|---|---|---|---|---|
| Amoxicillin | See the Infective Endocarditis chapter | GI upset, hypersensitivity | See the Infective Endocarditis chapter | Single dose, 30-60 minutes before the qualifying dental procedure. |
Do not use
| Drug/intervention | Reason to avoid | Comments |
|---|---|---|
| Direct oral anticoagulants (apixaban, dabigatran, edoxaban, rivaroxaban) | Contraindicated for any mechanical heart valve — increased thromboembolism and bleeding versus warfarin in randomized trials | Not restricted for a bioprosthetic valve or TAVI plus AF, once the early post-implantation window has passed. |
| Beta-blockers | Blunt the compensatory tachycardia maintaining forward flow in acute severe aortic regurgitation | Resume for standard indications only after the valve lesion has been surgically corrected. |
| Intra-aortic balloon pump | Diastolic counterpulsation increases aortic diastolic pressure and worsens the regurgitant fraction | An absolute contraindication in aortic regurgitation of any severity. |
References
- 2020 ACC/AHA Guideline for the Management of Patients With Valvular Heart Disease — Circulation, American College of Cardiology/American Heart Association Joint Committee on Clinical Practice Guidelines (Otto CM, Nishimura RA, Bonow RO, et al.). Circulation 2021;143(5):e72-e227
- 2021 ESC/EACTS Guidelines for the Management of Valvular Heart Disease — European Heart Journal, European Society of Cardiology/European Association for Cardio-Thoracic Surgery (Vahanian A, Beyersdorf F, Praz F, et al.). Eur Heart J 2022;43(7):561-632
- Intensive Lipid Lowering with Simvastatin and Ezetimibe in Aortic Stenosis — New England Journal of Medicine (Rossebø AB, Pedersen TR, Boman K, et al.). N Engl J Med 2008;359(13):1343-1356
- 2019 Canadian Cardiovascular Society Position Statement for Transcatheter Aortic Valve Implantation — Canadian Journal of Cardiology, Canadian Cardiovascular Society (Asgar AW, Ouzounian M, Adams C, et al.). Can J Cardiol 2019;35(11):1437-1448
- Dabigatran versus Warfarin in Patients with Mechanical Heart Valves — New England Journal of Medicine (Eikelboom JW, Connolly SJ, Brueckmann M, et al.). N Engl J Med 2013;369(13):1206-1214
- Bioprosthetic and Mechanical Heart Valves: Antithrombotic Therapy — Thrombosis Canada. Thrombosis Canada Clinical Guide, October 2025
Professional reference only. Apply clinical judgment and verify patient-specific decisions against current authoritative guidance and product information.