Two new recommendations for perioperative cardiovascular disease evaluation and management for patients undergoing noncardiac surgery were just released, one from the US and one from Europe (will limit review to common pre-operative primary care issues).
The US guidelines (see doi:10.1016/j.jacc.2014.07.944) reviews the risk factors for perioperative cardiovascular mortality, including the traditional ones (see paper for details):
–MI within the past 6 months, and esp. within the past 2 months
–heart failure, esp. decompensated, and more so in those with reduced ejection fraction
–cardiomyopathies present special management issues, though data on postoperative outcomes is limited and with mixed results
–valvular heart disease, noting the utility of preop echocardiography in those with suspected moderate or greater degrees of valvular disease and that recent advances in preoperative and operative monitoring/therapy have significantly reduced the risk of cardiac events — even those with severe AS and valve area <1cm2 now have only a slight increase in cardiac mortality (2.1% vs 1% at 30 days)
–arrhythmias typically need monitoring but more recent trials suggest they confer less cardiac risk — though their presence should trigger evaluation for underlying cardiopulmonary disease, especially if sustained or are associated with hemodynamic compromise
–high-grade conduction abnormalities such as complete A-V block may require pacing, but even left or right bundle-branch blocks only rarely progress perioperatively.
–also noted: preoperative natriuretic peptide has been found to be an independent risk factor, though requires further prospective studies, and other biomarkers have been incorporated into some of the risk models, including C-reactive protein and creatinine
There are 3 risk calculators noted in the paper, including:
– http://jaccjacc.cardiosource.com/acc_documents/2014_Periop_GL_Data_Supplement_Tables.pdf
– http://www.riskcalculator.facs.org/
– http://www.surgicalriskcalculator.com/miorcardiacarrest
For cardiac testing recommendations:
–first, evaluate functional status, a reliable predictor of cardiac events, with the increased risk if patients unable to perform at least 4 METs of activity (e.g., climbing a flight of stairs or walking up a hill, walking on level ground at 4 mph, or performing heavy work around the house). There are also formal instruments to evaluate (e.g. Duke Activity Status Index).
–those patients to undergo nonemergent surgery and are unable to perform 4 METs activity should have pharmacologic stress testing, with potential revascularization if abnormal.
–other evaluations include 12-lead EKG if known cardiovascular disease, significant arrhythmia, peripheral arterial disease, cerebrovascular disease, or significant structural heart disease, “except for those undergoing low-risk surgery” and (lower level of certainty) if asymptomatic patients without known cardiovascular disease. In all recommendations, not necessary if low-risk surgery. If doing EKG, should be within 1-3 months prior to surgery in stable patients. So, current imperative to do EKG within one month of cataract surgery seems quite unnecessary!!
–for patients with potential LV dysfunction on clinical evaluation, reasonable to do echo (in clinically stable, okay if echo done within past year).
–in those with stents: if drug-eluting, best to delay elective noncardiac surgery for 1 year (and at least 180 days). With bare metal stents, delay at least 30 days.
For perioperative therapy:
–only do coronary revasc if indicated according to existing recommendations, don’t do just for perioperative management.
–new recommendations for b-blockers (after discrediting the Dutch DECREASE trials for improprieties, as well incorporating the results of the new POISE-II trial): continue them if they were used chronically before surgery, may be reasonable to begin them in those with intermediate or high risk myocardial ischemia in preop risk stratification (paying close attention to adverse effects: hypotension, bradycardia, etc.), may be reasonable in those with 3 or more risk factors (diabetes, heart failure, CAD, renal insufficiency, stroke), and if going to use them, begin more than 1 day prior to surgery. –statins should be continued in patients already on them, and are reasonable if patient undergoing vascular surgery (who should probably have been on them anyway…).
–don’t give alpha-2 agonists (e.g. clonidine) perioperatively. Some studies suggest that calcium blockers (esp. diltiazem) may have benefit, but no recommendation. Can continue ACE-I or ARBs perioperativley.
–for antiplatelet drugs: those with recent stents should continue with dual antiplatelet therapy unless risk of bleeding outweighs benefit; in those without stents, may be reasonable to continue aspirin unless risk outweighs benefit; don’t initiate aspirin prior to surgery if no stent.
–anticoagulants: can continue in surgery with minimal bleeding risk (cataracts, minor derm procedures). For those on warfarin, bridging therapy (heparin) useful if high risk (mechanical mitral valve, or aortic valve plus another risk factor, such as afib, prior thromboemboli, LV dysfunction). Important issue with the newer thrombin inhibitors is that they are not reversible. So stop them at least 48 hours prior to surgery.
The European recommendations (see doi: 10.1093/eurheartj/ehu282) seem pretty similar on my less intense review. They do suggest a resting echo in asymptomatic patients without signs of cardiac disease but undergoing high-risk surgery. For b-blockers, they specifically recommend atenolol or bisoprolol. indications similar to US recs, though more strongly point out that these should not be fixed dose, but titrated to resting heart rate of 60-70 and systolic bp>100mmHg, and should be started more than one day prior to surgery (as with US recs), though they suggest preferably 7-30 days before. For statins, they suggest trying to start 2 weeks before surgery, with same indications as with US recs. ACE/ARBs, if indicated (e.g. pt with heart failure) should begin at least 1 week prior to surgery. They do seem a bit more aggressive in some issues: e.g., consider pre-op routine carotid artery imaging in patients undergoing vascular surgery. Most of other recommendations are pretty similar to the US ones.
Geoff