Open Heart Surgery — How It Works, Benefits & Recovery — Procedure Guide, Recovery & Risks | MyMedicPlus

Open heart surgery is a major cardiac surgical procedure in which the chest is opened via median sternotomy (dividing the breastbone/sternum) to directly access the heart for repair or replacement of its structures. The term encompasses a broad range of operations: coronary artery bypass grafting (CABG) to restore blood flow past blocked coronary arteries; valve repair or replacement (aortic, mitral, tricuspid); repair of congenital heart defects (atrial septal defect, ventricular septal defect, tetralogy of Fallot); aortic root replacement; cardiac tumour resection; and cardiac transplantation. The majority of open heart operations require cardiopulmonary bypass (CPB) — a heart-lung machine that temporarily takes over the pumping and oxygenation functions of the heart and lungs, allowing the surgeon to operate on a still, bloodless field. Some procedures — particularly CABG — can be performed off-pump (beating-heart surgery, OPCAB) using stabilisation devices to immobilise segments of the coronary artery during anastomosis. Open heart surgery is performed by a cardiothoracic surgical team (cardiac surgeon, perfusionist managing CPB, anaesthetist, scrub nurse, assistant) in a specialised cardiac surgical theatre with full monitoring, intra-operative transoesophageal echocardiography, and rapid access to intensive care.

Open heart surgery is indicated for a broad range of structural cardiac conditions where the expected benefit in survival, functional capacity, or quality of life justifies the surgical risk. Key indications include: coronary artery disease (CAD) with three-vessel or left main stem disease, or multi-vessel disease with impaired left ventricular function — where CABG provides superior survival and symptom relief compared to percutaneous coronary intervention (PCI) or medical therapy alone; severe aortic stenosis (aortic valve area <1 cm², mean gradient >40 mmHg, symptomatic) where surgical aortic valve replacement (SAVR) is indicated in low-to-intermediate risk patients; severe mitral regurgitation from degenerative disease where repair is technically achievable; endocarditis with structural valve destruction, perivalvular abscess, or uncontrolled infection; complex congenital heart disease requiring correction in infancy, childhood, or adulthood; ascending aortic aneurysm ≥5.5 cm (or ≥5 cm in Marfan syndrome or bicuspid aortic valve) at risk of dissection; acute Type A aortic dissection (emergency indication); and cardiac failure refractory to medical therapy in patients eligible for transplantation. Patient selection involves cardiology-cardiac surgery heart team decision (as per ESC/EACTS and AHA/ACC guidelines), assessment of surgical risk score (EuroSCORE II or STS score), and patient preferences regarding recovery and risk tolerance.

Under general anaesthesia with comprehensive invasive haemodynamic monitoring (arterial line, central venous pressure, pulmonary artery catheter in complex cases), a median sternotomy is performed using an oscillating saw. For CABG, the internal mammary artery (LIMA for the LAD artery) and saphenous vein or radial artery grafts are harvested. Heparin is administered to prevent clotting. The aorta and right atrium (or femoral vessels) are cannulated to connect to the CPB circuit. The heart is arrested with cold potassium cardioplegia solution; additional doses are given every 20–30 minutes to maintain arrest and myocardial protection. For CABG, the distal anastomoses (graft to coronary artery) are performed on the arrested heart using 7–0 prolene sutures under magnification; the proximal anastomoses (graft to aorta) are performed after cross-clamp removal. For valve surgery, the valve is approached through the aortic root or left atrium. The diseased valve is excised and a prosthetic mechanical or bioprosthetic valve of appropriate size is sutured in place. After repair or replacement, the heart is de-aired and the cross-clamp removed — the heart restarts in sinus rhythm spontaneously or with defibrillation. Weaning from CPB is achieved gradually with vasopressor and inotropic support. Protamine reverses heparin. Epicardial pacing wires and mediastinal chest drains are placed. The sternum is closed with stainless steel wires; layered fascial and skin closure completes the procedure.

CABG surgery demonstrates superior long-term survival versus PCI for multi-vessel CAD with complex anatomy (SYNTAX score >22) or left main disease: the SYNTAX trial demonstrated 5-year survival of 77% for CABG versus 71% for PCI in three-vessel disease; 15-year data from the BEST trial confirm the survival advantage. CABG also reduces rates of myocardial infarction and repeat revascularisation compared to PCI at 10 years. Surgical aortic valve replacement for severe aortic stenosis relieves symptoms (angina, dyspnoea, syncope) in more than 95% of patients and dramatically improves survival: untreated severe symptomatic aortic stenosis carries 50% mortality at 2 years, which is almost entirely eliminated by successful surgery. Mitral valve repair for degenerative disease at specialist centres achieves freedom from reoperation of >90% at 10 years with operative mortality <1%, preserving left ventricular function and avoiding anticoagulation. Congenital heart defect correction enables children and adults to achieve normal or near-normal life expectancy. Patient-reported outcomes consistently demonstrate marked improvement in functional class (NYHA), exercise capacity, and quality of life scores at 6–12 months following successful cardiac surgery.

Open heart surgery carries inherent procedure-specific and patient-related risks. Operative mortality: overall 1–2% for isolated elective CABG in low-risk patients (EuroSCORE II 0.5–1%); rising to 3–8% for complex combined procedures (CABG + valve); 15–20%+ for emergency operations (acute aortic dissection). Stroke: 1–3% for elective CABG; higher for valve procedures requiring longer CPB and aortic manipulation, in elderly patients, or in patients with aortic atheroma detected on epiaortic ultrasound. Renal failure requiring temporary dialysis: 1–5%; permanent dialysis in 0.5–1%. Deep sternal wound infection (mediastinitis): 0.5–2%; higher in obese patients, diabetics, patients on prolonged steroids; requires surgical debridement and vacuum-assisted closure or pectoralis major advancement flap. Atrial fibrillation: 25–40% in the post-operative period (peak day 2–3), usually self-limiting or responsive to amiodarone and cardioversion; associated with increased stroke risk during the episode. Prolonged ventilation (>24 hours): 5–10% due to low cardiac output, respiratory complications, or pre-existing COPD. Cognitive dysfunction: neurocognitive impairment is detectable in 20–40% at 6 weeks (related to CPB embolic and inflammatory effects) but largely resolves by 6 months in most patients. Haemorrhage requiring reoperation: 2–5%.

Following 1–3 days in the cardiac intensive care unit (ICU) with continuous monitoring, patients transfer to the cardiac surgical high-dependency unit for 4–7 days. Chest drains and epicardial pacing wires are removed on day 1–2; urinary catheter on day 1. Respiratory physiotherapy (incentive spirometry, deep breathing exercises) begins immediately to prevent atelectasis and pneumonia. Mobilisation commences on day 1–2 with physiotherapy guidance. Hospital stay totals 7–10 days. Beta-blockers (metoprolol, bisoprolol) prevent post-operative atrial fibrillation and provide cardioprotection; aspirin 75–100 mg daily maintains graft patency after CABG. Warfarin (target INR 2.5–3.5) is prescribed for 3 months after mechanical valve replacement and indefinitely thereafter. The sternal incision heals over 6–8 weeks — during this period lifting >5 kg and pushing/pulling are prohibited, and driving is not permitted for 6 weeks. Full-time return to sedentary work at 6–8 weeks; physically demanding work at 10–12 weeks. Cardiac rehabilitation (12-week supervised aerobic exercise programme) is strongly recommended for all patients — it reduces 5-year mortality by 20–25%, improves functional capacity by 15–20%, and reduces readmission rates. Echocardiography at 6–8 weeks assesses cardiac function and valve repair/replacement integrity.