Pre-operative detection of valvular heart disease by anaesthetists.

We prospectively estimated the prevalence of heart murmurs in 2522 consecutive adult non-cardiac surgery patients during pre-operative evaluation. Factors that contribute to the detection of a heart murmur were identified, and echocardiography was used to evaluate to what extent a murmur reflected presence of valvular heart disease. A cardiac murmur was detected in 106 patients (prevalence 4.2%, 95% CI: 3.5-5.1%). Multivariable logistic regression analyses showed that age and general physical impression were independently associated with detecting a murmur (p-values < 0.01). In 83 (79%) of the patients with a murmur, an echocardiographic diagnosis was available: 39% had aortic valve abnormalities, 24% had mitral valve regurgitation, 7% had other valvular heart disease and 30% did not have any abnormality. Thus, 58 of the 83 patients had valvular heart disease (positive predictive value using routine cardiac auscultation for diagnosing VHD: 70%, 95% CI: 59-79%). Murmurs in patients younger than 40 years never reflected valvular heart disease. Pre-operative cardiac auscultation seems only reasonable in patients aged 40 years or older. Subsequent echocardiography in these selected patients is necessary.