AHA/ACC Guidelines (2007)

AHA/ACC Guidelines (2007) – Perioperative Cardiovascular Evaluation of the Patient undergoing Non-cardiac Surgery

Take Home Message = if assessment and evaluation not indicated irrespective of perioperative context then just crack on (its all about symptoms).

3 factors involved in risk stratification:

1. Patient risk factors (high, intermediate and low risk)
2. Functional capacity (<4METS= low, >4METS= high)
3. Surgery (high, intermediate and low risk)

CLINICAL ASSESSMENT

Active Medical Problems/Major Risk Factors

• unstable angina
• recent MI (< 1 month)
• uncontrolled heart failure
• significant arrhythmias (high grade AV block, symptomatic arrhythmias, supraventricular arrhythmias with a rapid ventricular rate)
• severe valvular disease
• recent CABG or PCI (<6 weeks)

Clinical Predictors (Lee’s Criteria)/Intermediate Risk Factors

• previous MI (>1 month)
• stable mild angina
• compensated heart failure
• renal impairment (Cr > 170)
• DM (on insulin)

Risk of Perioperative Cardiac Events (AMI,APO, CVA, arrhythmia, death)

• 0 factors = 0.4%
• 1 = 1%
• 2 = 6.6%
• 3-5 = 11%

Minor Risk Factors

• advanced age
• abnormal ECG
• arrhythmia
• low functional capacity
• previous CVA
• uncontrolled HT

FUNCTIONAL CAPACITY

• 1MET= personal cares
• 2METS = walk indoors
• 3METS = walk a block on level ground, dusting and washing dishes
• 4METS = climb a flight of stairs or walk up hill
• 5METS = run a short distance
• 6METS = scrubbing floors or lifting heavy objects
• 7-9METS = golf, bowling, dancing, doubles tennis, throwing rugby ball
• >10METS = swimming, singles tennis, basketball, skiing

SURGERY

High Risk (>5%)

• major emergency surgery
• aortic or major open vascular surgery

Intermediate Risk (1-5%)

• intraperitoneal and intrathoracic surgery
• carotid endarterectomy
• head and neck surgery
• orthopaedic surgery
• prostate surgery

Low Risk (<1%)  

• endoscopic procedures
• superficial procedure
• cataract surgery
• breast surgery
• ambulatory surgery

 INVESTIGATIONS

• FBC; anaemia
• 12 lead ECG; conduction abnormalities, arrhythmia, Q waves, ischaemic change
• U+E; renal function
• ECHO; LV function, valvulopathy
• Radionucleotide angiography (not predictive of intraoperative ischaemia)
• ETT; good assessment as assesses symptoms and workload but only indicated if there are pre-existing symptoms of concern (sensitivity 70% and specificity 80%).
• Dobutamine stress ECHO;
• Radionucleotide stress testing; can quantify the areas of myocardium that is @ risk
• ANGIO: anatomical nature of lesion and ability to revascularise

MANAGEMENT  

Preoperative

Preoperative CABG – if symptoms are stable, CABG doesn’t change risk of MI of death  (CARP study & DECREASE study).

Preoperative PCI – again, unless intervention is indicated in and of itself it doesn’t change risk.

• balloon angioplasty -> delay surgery 2-4 weeks and keep anti-platelet agents going.
• bare metal stent -> delay surgery 4-6 weeks (will be on clopidogrel for this time too).
• drug eluting stents -> delay surgery for 12 months (will be on dual platelet therapy).
• if patients must undergo therapy keep aspirin going and restart clopidogrel as soon as possible.

Perioperative management of patients with prior PCI

• see above time frames (4 weeks, 6 weeks & 12 months) -> try and keep dual anti-platelet therapy going.
• if can’t, keep aspirin going and reinstitute clopidogrel as soon as possible -> there is no evidence that other agents decrease risk of stent thrombosis.

Perioperative management of patients who have received intracoronary brachytherapy

• gamma or beta brachytherapy used to treat recurrent in-stent restenosis.
• continue anti-platelet agents if possible.

Perioperative management of the patient who requires PCI and surgery soon after

Use same time lines based on when surgery indicated:

• 4 weeks -> balloon
• 6 weeks -> bare metal stent
• 12 months -> drug eluting stent
• can put stents in and then deal with restenosis if it takes place
• also CABG + non-cardiac surgery is an option

Perioperative Beta-blockers

• aim = to decrease perioperative MI and death
• should start weeks prior to surgery
• use longer acting agents
• aim for a HR <65/min
• continue perioperatively
• POISE trial: showed that introduction of betablockers on the day of surgery resulted in an increase in adverse events and mortality therefore acute commencement not advised.

Perioperative Statins

• keep going
• decreased risk of MI and death

Alpha 2 Agonists

• reduction in perioperative MI and mortality

Perioperative Calcium channel blockers

• reduced SVTand ischaemia.
• trend towards decreased MI and death.

Intraoperative

Electomagnetic Interference + ICD’s and Pacemakers

• recent evaluation (within 3-6 months)
• reprogram to an asynchronous mode (D00 or V00)
• ICD -> turn off their tachyarrhythmia treatment algorithms, place defibrillation paddles far away from device (AP ideal)
• otherwise standard care

Postoperative

• monitor clinically for MI.
• if develops PCI needs to considered in context of bleeding risk.
• manage acutely with early consultation with cardiology.

References and Links

Journal articles and textbooks

• Fleisher LA et al. ACC/AHA 2007 guidelines on perioperative cardiovascular evaluation and care for noncardiac surgery: executive summary: a report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines. Anesth Analg. 2008 Mar;106(3):685-712. Mar;106(3):685-712. PMID: 18292406
• POISE Study Group. Effects of extended-release metoprolol succinate in patients undergoing non-cardiac surgery (POISE trial): a randomised controlled trial. Lancet. 2008 May 31;371(9627):1839-47. PMID: 18479744
• Fleisher LA et al. 2009 ACCF/AHA focused update on perioperative beta blockade incorporated into the ACC/AHA 2007 guidelines on perioperative cardiovascular evaluation and care for noncardiac surgery. J Am Coll Cardiol. 2009 Nov 24;54(22):e13-e118. PubMed PMID: 19926002