Coronary flow reserve

Abstract

The assessment of coronary flow reserve by transthoracic echocardiography has recently been introduced into clinical practice with gratifying results for the diagnosis of left anterior descending artery disease, as reported by several independent laboratories. This technological novelty is changing the practice of stress echocardiography for three main reasons. First, adding coronary flow reserve to regional wall motion allows us to have - in the same sitting - a diagnostic marker of high specificity (regional wall motion) and high sensitivity (coronary flow reserve), with an obvious improvement in overall diagnostic accuracy. Second, the technicalities of coronary flow reserve shift the balance of stress choice in favor of vasodilators, which are a more robust hyperemic stress and are substantially easier to perform with dual imaging than dobutamine or exercise. Third, the coronary flow reserve adds a quantitative support to the exquisitely qualitative assessment of wall motion analysis, thereby facilitating the communication of stress echocardiography results to the cardiological world outside the echocardiography laboratory. The next challenges involve the need to expand the exploration of coronary flow reserve to the right and circumflex coronary artery and to prove the additional prognostic value - if any - of coronary flow reserve over regional wall motion analysis, which remains the cornerstone of clinically driven diagnosis in the stress echocardiography laboratory. © 2009 Springer Berlin Heidelberg.