Can Patients with Critical Aortic Stenosis Undergo Noncardiac Surgery
without Intervening Aortic Valve Replacement?

M. Chadi Alraies
30 mar 2009--Case Presentation: A 65-year-old female patient with past medical history of
hypertension, diabetes mellitus, and hyperlipidemia was seen for preoperative
clearance for repair of right femur fracture. Patient denied chest pain but admitted
to progressively worsening dyspnea on exertion over the last few months. Her
medications were lisinopril, metformin, and simvastatin. Vital signs on admission
were stable, with a blood pressure of 136/72 mm Hg and heart rate of 92
bpm. Labs were normal. Her exam was unremarkable except for a 3/6 harsh systolic
murmur. Echocardiogram revealed critical aortic stenosis (AS) with valve
area of 0.7 cm2. Cardiology recommended aortic valve replacement (AVR), but
patient refused surgery. Patient chose to undergo fracture repair surgery despite
the explained risks. She was started on beta-blockers and appropriate anesthetic
precautions were undertaken. Her postoperative course was complicated by prolonged
ventilator support, but patient was successfully extubated after 2 days and
was discharged in stable condition.

Discussion: Per the American College of Cardiology/American Heart
Association guidelines, severe valvular disease is a major clinical predictor
of cardiac risk and elective noncardiac surgery (NCS) should be delayed for
intervening cardiac catheterization and/or possible valve surgery. However,
several reviews have suggested that patients with severe AS may undergo
NCS with relative safety if appropriate perioperative care is provided and
careful management of the pathophysiologic changes associated with AS
is undertaken. O’Keefe et al reported that in 48 severe AS patients (mean
valve area 0.6 cm2) who were not eligible for AVR and underwent NCS,
only 1 cardiac event with no deaths and a complication rate of about 2%
was seen. This would compare favorably with the national 4% mortality rate
for AVR reported by the Society of Thoracic Surgeons. On the other hand, a
subsequent report of 19 patients with severe AS (mean valve area < 0.5 cm2)
reported 2 perioperative deaths. Raymer and Yang compared 55 patients with
signifi cant AS (mean valve area 0.9 cm2) with case-matched controls with
similar preoperative risk profi les other than AS undergoing similar surgeries,
and cardiac complication rates were not signifi cantly different between
the two groups. Thus, patients with severe AS may undergo indicated NCS
provided that the presence of severe AS is recognized preoperatively and the
patients receive intensive perioperative care.

Conclusion: Critical AS needs to be detected preoperatively, given its prognostic
importance. When detected, surgery may still be considered even if AVR
is not feasible, and requires a comprehensive co-management team involving
anesthesia, cardiology, surgery, and internal medicine.