Valve surgery

Surgical approach

• Access and setup
  • Median sternotomy for most open valve surgery; occasionally minimally invasive (right mini-thoracotomy/partial sternotomy) for AVR/MVR in selected patients
  • Aortic and right atrial (bicaval if MV/TV) cannulation for cardiopulmonary bypass (CPB); systemic heparinisation
  • Aortic cross-clamp; cardioplegia (antegrade/retrograde) for myocardial protection; venting (LV vent via RSPV/PA) as needed
• Aortic valve surgery (SAVR)
  • Aortotomy; excision of native valve; annular debridement ± annular enlargement; implantation of mechanical or bioprosthetic valve
  • Root/ascending aorta procedures may be combined (e.g., Bentall, root replacement) in aortopathy/endocarditis
• Mitral valve surgery (repair/replacement)
  • Left atriotomy (or trans-septal); repair preferred when feasible (annuloplasty ring, leaflet resection, chordal replacement) or replacement
  • May include AF surgery (MAZE) and left atrial appendage closure
• Tricuspid/pulmonary valve surgery
  • Often concomitant with left-sided surgery; tricuspid repair (annuloplasty) common; replacement less common
  • Pulmonary valve replacement in congenital/redo settings; may be on/off CPB depending on approach
• Transcatheter options (context)
  • TAVI (usually transfemoral; alternatives: trans-subclavian, transaortic, transapical)
  • Transcatheter edge-to-edge mitral repair (e.g., MitraClip) and valve-in-valve procedures in selected patients

Anaesthetic management (headline)

• Type of anaesthesia and airway
  • Open valve surgery: General anaesthesia with endotracheal tube; lung isolation rarely required unless thoracotomy/minimally invasive approach (consider DLT/bronchial blocker)
  • TAVI: GA with ETT or monitored anaesthesia care (MAC) with sedation depending on centre/patient; GA favours TOE and controlled ventilation
• Duration and pain
  • Open single-valve surgery typically ~3–6 h (longer if redo, combined procedures, complex repair, endocarditis)
  • Sternotomy pain: moderate–severe initially; multimodal analgesia ± regional fascial plane blocks (parasternal/pectointercostal, erector spinae) and opioid-sparing strategies
  • TAVI/TEER: usually low–moderate pain (groin access); shorter case (often 1–2.5 h)
• Monitoring and access
  • Standard monitoring
  • Large-bore IV access
  • Arterial line pre-induction (radial; consider femoral if severe AS/poor pulses)
  • BIS monitor
  • Central venous access (asleep)
  • Temperature
  • Urine output
  • TOE for open valve surgery (and many TAVI / mitral interventions):
    • Pre-CPB diagnosis, guidance of cannula, de-airing, post-repair assessment
  • Consider pulmonary artery catheter in severe pulmonary HTN/RV dysfunction/complex cases
• Cardiopulmonary bypass considerations
  • Anticoagulation:
    • Heparin to ACT target (local protocol):
      • Typically give: 300–400 units/kg IV heparin
      • Target ACT: 480 seconds (for CPB)
        • ACT should be done 3-5 mins after heparin administration
      • Vigilance for heparin resistance (AT deficiency)
        • Suspect if inadequate ACT rise despite appropriate dosing
        • Consider additional heparin ± antithrombin concentrate / FFP
    • Protamine reversal:
      • Dose of ~1 mg per 100 units of heparin given
        • Adjust depending on time since heparin administration and ACT
        • Typical max initial dose often ≤ 300 mg (varies by centre)
      • Some centres have ACT-guided or protamine titration calculators
  • Myocardial protection, ventilation strategy, glycaemic control, temperature management, transfusion/haemostasis plan
• Postoperative destination
  • ICU/HDU; aim for early extubation if stable; anticipate pacing needs, inotropes/vasopressors, bleeding, arrhythmias

Indications and common procedures

• Aortic stenosis: symptomatic severe AS, LV dysfunction, very severe AS, or when undergoing other cardiac surgery
• Aortic regurgitation: symptoms, LV dilatation/dysfunction, acute severe AR (e.g., endocarditis/dissection)
• Mitral regurgitation: symptomatic severe MR, LV dysfunction/dilatation, new AF/pulmonary HTN; repair preferred in degenerative MR
• Mitral stenosis: symptomatic severe MS, pulmonary HTN, recurrent emboli; consider percutaneous balloon valvotomy if suitable
• Tricuspid regurgitation: severe TR with symptoms/RV dilatation, often concomitant with left-sided surgery
• Redo valve surgery: prosthetic degeneration, paravalvular leak, endocarditis, thrombosis; higher risk (adhesions, bleeding, myocardial injury)

Preoperative assessment

• History/examination: symptoms (angina, syncope, dyspnoea), exercise tolerance, heart failure signs, arrhythmia (AF), embolic events, infective endocarditis features
• Echocardiography essentials: valve lesion severity, LV/RV function, pulmonary pressures, other valve disease, aortic root/ascending aorta, presence of vegetations/thrombus
  • Severe AS: high gradient/velocity and/or low-flow low-gradient with reduced EF; assess valve area and stroke volume index
  • MR: mechanism (degenerative vs functional), severity, suitability for repair
• Coronary disease: angiography/CTCA as indicated; plan for concomitant CABG
• Anticoagulation/antiplatelets: mechanical valves (warfarin), AF, recent stent; plan interruption/bridging; check INR and bleeding risk
• Endocarditis: blood cultures, antibiotics timing, embolic risk, conduction abnormalities, potential for abscess; anticipate friable tissue and bleeding
• Comorbidity and frailty: renal dysfunction, COPD, cerebrovascular disease, carotid disease, anaemia, diabetes; risk scoring (EuroSCORE II) informs but does not replace judgement

Lesion-specific haemodynamic goals

• Aortic stenosis
  • Maintain sinus rhythm and adequate preload; avoid tachycardia and significant bradycardia; maintain afterload (coronary perfusion) and treat hypotension promptly (e.g., phenylephrine/noradrenaline)
  • Induction: slow, titrated; avoid vasodilation and myocardial depression; consider etomidate/ketamine-opioid techniques depending on patient
• Aortic regurgitation
  • Faster heart rate (reduce diastolic time), avoid bradycardia; reduce afterload to promote forward flow; maintain contractility; avoid excessive SVR
• Mitral stenosis
  • Avoid tachycardia (diastolic filling time), maintain sinus rhythm, cautious fluids (pulmonary oedema risk), avoid increases in PVR (hypoxia, hypercarbia, acidosis, pain)
  • AF with fast ventricular response can precipitate failure: plan rate control and cardioversion strategy
• Mitral regurgitation
  • Avoid bradycardia; modestly reduced afterload; maintain preload but avoid overload; maintain contractility; vasodilators/inodilators may help
• Tricuspid regurgitation / RV dysfunction / pulmonary HTN
  • Maintain RV perfusion (avoid hypotension), optimise preload (often narrow window), reduce PVR, maintain sinus rhythm/AV synchrony; consider inhaled pulmonary vasodilators (NO/prostacyclin) in severe cases

Intraoperative conduct (open valve surgery)

• Induction and maintenance
  • Pre-induction arterial line; consider vasopressor ready (phenylephrine/noradrenaline) especially in severe AS/MS/PHTN
  • Balanced GA with opioid + hypnotic + muscle relaxant; volatile or TIVA; avoid large swings in SVR/HR; ensure adequate depth before sternotomy
• TOE workflow
  • Pre-CPB: confirm lesion, ventricular function, volume status, other pathology (PFO, thrombus, atheroma), baseline gradients/regurgitation
  • Post-CPB: assess prosthesis function (leaflet motion, gradients, regurgitation), repair adequacy, LV/RV function, regional wall motion, pericardial effusion, de-airing
• CPB and separation
  • Before CPB: ensure ACT target achieved; antibiotics; glycaemic and temperature plan; discuss cardioplegia strategy and venting
  • Separation: optimise preload, rhythm (pacing wires), ventilation and acid-base, electrolytes (K/Mg/Ca), haemoglobin; choose vasopressor/inotrope based on physiology (LV vs RV failure, vasoplegia)
• Haemostasis and transfusion
  • Antifibrinolytic (e.g., tranexamic acid) per protocol; monitor coagulation (TEG/ROTEM if available); manage hypofibrinogenaemia/platelet dysfunction; consider cell salvage
  • Protamine reversal: give slowly; watch for hypotension, pulmonary vasoconstriction, anaphylactoid reactions; consider risk in prior protamine exposure, fish allergy (association debated), vasectomy, NPH insulin

Postoperative care and complications

• Common early issues: bleeding/tamponade, low cardiac output syndrome, vasoplegia, arrhythmias (AF, heart block), respiratory failure, AKI, delirium/stroke
• Pacing and conduction problems
  • AVR/TAVI can cause new LBBB/complete heart block; temporary pacing wires in open surgery; anticipate need for permanent pacemaker particularly after TAVI
• Anticoagulation after valve intervention (principles; follow local/cardiology guidance)
  • Mechanical valves: lifelong VKA (warfarin) with target INR depending on valve type/position and risk factors; bridging may be required perioperatively
  • Bioprosthetic valves: antiplatelet and/or short course anticoagulation may be used depending on position and patient factors (e.g., AF)
• Prosthetic valve complications
  • Thrombosis, pannus, endocarditis, structural valve degeneration (bioprosthesis), paravalvular leak, patient–prosthesis mismatch (high gradients)