Revised Cardiac Risk Index (RCRI) Calculator

The CCS 2017 and ESC 2022 guidelines recommend preoperative NT-proBNP (or BNP) measurement in patients with RCRI ≥ 1 undergoing non-cardiac surgery, to refine risk stratification beyond the RCRI alone. An elevated NT-proBNP (≥ 300 pg/mL) independently predicts perioperative MACE and death at 30 days and 1 year, even in patients with low RCRI scores.

If NT-proBNP is elevated: consider postoperative troponin surveillance for 48–72 hours to detect myocardial injury after non-cardiac surgery (MINS). If NT-proBNP is normal: proceed with reassurance that cardiac event risk is low. This biomarker-first strategy is increasingly preferred over routine preoperative stress testing, which has not been shown to improve outcomes when used indiscriminately.

Preoperative cardiac stress testing (exercise ECG, stress echocardiography, or myocardial perfusion imaging) is not routinely indicated before non-cardiac surgery. Guidelines recommend it only when the result would change management — typically in patients with RCRI ≥ 2, poor or unknown functional capacity (< 4 METs), and when surgery can be deferred for risk-reducing interventions if significant ischaemia is found.

The CARP trial (McFalls et al., 2004) demonstrated that preoperative coronary revascularisation did not reduce perioperative cardiac events or improve long-term survival in stable patients undergoing vascular surgery. Routine preoperative stress testing that leads to unnecessary revascularisation adds risk and delays surgery without improving outcomes. Reserve testing for patients in whom findings will genuinely alter the perioperative plan.

Perioperative beta-blocker therapy is one of the most debated topics in surgical medicine. Continue beta-blockers in patients already taking them — abrupt withdrawal increases perioperative cardiac risk (POISE-style rebound). Do not initiate high-dose beta-blockers on the day of surgery — the POISE trial showed that while metoprolol reduced MI, it significantly increased stroke and overall mortality when started acutely.

If initiating beta-blockers preoperatively in high-risk patients (RCRI ≥ 3, known IHD), start at a low dose at least 1 week (preferably 2–4 weeks) before surgery, and titrate gradually to a target heart rate of 60–70 bpm without hypotension. This approach is supported by AHA/ACC 2014 guidelines (Class IIb recommendation). Atenolol or bisoprolol are preferred over short-acting metoprolol. Avoid in patients with decompensated HF, active bronchospasm, or significant bradycardia.

Preoperative coronary revascularisation (PCI or CABG) is not indicated solely to reduce perioperative risk in stable patients. The CARP trial and subsequent meta-analyses show no benefit of prophylactic revascularisation before non-cardiac surgery in patients with stable coronary artery disease. Revascularisation should only be performed if it would be indicated independently of the planned surgery — such as for acute coronary syndrome, left main disease, or severely symptomatic multi-vessel disease refractory to medical therapy.

If revascularisation is performed, surgery should be delayed: at least 14 days after balloon angioplasty, 3–6 months after bare-metal stent (BMS), and ideally 6–12 months after drug-eluting stent (DES) to allow adequate dual antiplatelet therapy (DAPT). Premature DAPT discontinuation for surgery carries a high risk of stent thrombosis.

If the surgery is emergent (life- or limb-threatening, or time-sensitive within hours), proceed directly to the operating theatre. Calculate RCRI for documentation and postoperative risk stratification, but do not delay surgery for preoperative testing. Focus on perioperative haemodynamic optimisation, and order postoperative troponin surveillance at 24 and 48 hours in patients with RCRI ≥ 1 or other cardiac risk factors.

Screen for active cardiac conditions that require evaluation and treatment before elective surgery regardless of RCRI: unstable coronary syndromes (recent MI within 60 days, unstable angina), decompensated heart failure (NYHA IV, new-onset), significant arrhythmias (high-grade AV block, symptomatic bradycardia, supraventricular tachycardia with uncontrolled rate, symptomatic ventricular tachycardia), and severe valvular disease (symptomatic aortic stenosis, symptomatic mitral stenosis). If present, defer elective surgery and address the cardiac condition first.

Determine the inherent surgical risk: low-risk procedures (superficial, endoscopic, cataract, breast — < 1% MACE) can proceed without further cardiac testing regardless of RCRI. For intermediate- and high-risk procedures, calculate RCRI. If RCRI = 0: proceed to surgery with routine monitoring. If RCRI ≥ 1: assess functional capacity (step 4) and consider biomarker testing.

Functional capacity ≥ 4 METs (ability to climb a flight of stairs, walk two blocks on the flat, do heavy housework, or play a round of golf) without symptoms is reassuring. For patients with RCRI ≥ 1 but good functional capacity, proceed to surgery without further testing. For patients with RCRI ≥ 1 and poor (< 4 METs) or unknown functional capacity, consider further risk stratification: measure NT-proBNP (CCS/ESC), or proceed to stress testing if the result would change management. The DASI (Duke Activity Status Index) questionnaire provides a validated, standardised functional capacity assessment.

Before surgery, ensure: continuation of chronic beta-blockers and statins; appropriate management of antiplatelet/anticoagulant therapy; glycaemic optimisation in diabetic patients (HbA1c ideally < 8.5% for elective procedures); blood pressure controlled; and anaemia corrected where possible. For patients with elevated NT-proBNP or positive stress testing, involve the cardiology and anaesthesia teams in shared decision-making about proceeding, modifying, or deferring surgery.