Aortic Valve Replacement Surgery


Patient Presentation:
Patient is a 93-year-old right-handed male with a past medical history of type 2 diabetes, coronary artery disease, peripheral vascular disease, heart failure, atrial fibrillation, and hypertension who presented to the ER with complaints of progressively worsening shortness of breath, fatigue, orthopnea, and paroxysmal nocturnal dyspnea x 2 weeks. Patient was awake, alert, and oriented on assessment and he denied fevers, chills, chest pain, nausea, vomiting, and coughing. He was well-developed, well-nourished, and did not appear to be in acute respiratory distress. Bilateral crackles in the lungs, normal S1 and S2, and a systolic ejection murmur were heard on auscultation. Vital signs were: BP 145/86, HR 96, RR 16, temperature 36.5°C, and O2 Sat of 96% on room air.

Differential List:
Myocardial infarction, angina, congestive heart failure (CHF) exacerbation, pneumothorax, pneumonia, and heart valve disease.

Lab and Diagnostic Studies:
WBC 4.5, RBC 4.18, Hgb 12.7, Hct 39.1, platelet 124, LFTs were normal, BNP 466, Na+ 139, K+ 4.3, HCO3 25, BUN 25, creatinine 1.20, troponin-I 0.052, and CK-MB 2.9. Noninvasive stress test was abnormal. Subsequently a 2D echocardiogram and a cardiac catheterization were recommended. Echocardiogram revealed mild concentric left ventricular hypertrophy, mildly reduced left ventricular systolic function, ejection fraction (EF) of 40-45%,  regional wall motion abnormalities, right ventricle was of normal size and function, mildly dilated left atrium, moderate mitral regurgitation, severe valvular aortic stenosis (AS), trace aortic regurgitation, and trace pulmonic valvular regurgitation. A cardiac catheterization revealed normal coronary arteries, mild pulmonary hypertension and critical AS. A chest x-ray was also ordered, which revealed a normal size heart and pulmonary edema.

Treatment:
Patient was diagnosed with an exacerbation of CHF requiring IV Lasix® for diuresis, moderate mitral valve regurgitation, and critical AS. Subsequently patient was recommended for an urgent aortic valve replacement (AVR) surgery.

AVR is a surgical procedure used to replace a patient’s diseased aortic valve with a prosthetic valve, which can be mechanical or bioprosthetic. Bioprosthetic valves are usually made from pig, cow, horse, or human tissue.

Outcome:
Patient successfully underwent AVR surgery using a 25mm magna bioprosthetic valve. Mitral valve replacement surgery was not recommended at the time of the AVR surgery, probably due to the patient’s advanced age and comorbidities. Anticoagulation therapy is not indicated with bioprosthetic valves. However, if patient had undergone the AVR with a mechanical valve, long anticoagulation therapy would have been critical to prevent blood clots. Once patient was medically stable, he was discharged home on PO amiodarone for his atrial fibrillation and aspirin for blood clot prevention.

Case created by Nafisa Jiddawi, 2012.