Left main coronary artery disease: A review of the spectrum of noninvasive diagnostic modalities

Abstract

Medically managed significant left main (LM) stem disease has been considered a determinant of increased cardiac mortality approaching 50% at 3-year follow-up. Despite the clinical significance of LM disease, studies comparing the various diagnostic modalities, especially noninvasive, are sparse. Clinicians, particularly imagers, should be aware of the strengths and weaknesses of existing modalities to diagnose LM disease as integrating many clues (history, symptoms, electrocardiogram, and stress hemodynamics are essential to suspect this diagnosis and proceed to the next step). Here we review the existing data on the current role of electrocardiography, nuclear myocardial perfusion imaging (single photon emission computed tomography and positron emission tomography), stress echocardiography, cardiac computed tomography, and cardiac magnetic resonance imaging in diagnostic evaluation of LM disease. Wherever applicable we have extended our discussion to multivessel coronary artery disease encompassing scenarios where LMS can present as LM equivalent with or without extensive multivessel coronary artery disease.

Left main disease diagnosis: The Achilles heel or the great strength of modern cardiac imaging?

“…Based on their analysis, the authors state that ''…noninvasive detection of significant LM stenosis is critically important given the underlying extent of myocardium at risk''. 1 They also rightfully conclude that all the reviewed noninvasive methodologies have their intrinsic limitations in assessment of extent of LM disease.…”

“…1 The authors included a total of 102 references covering this important topic and provided several very interesting Figures. I would specifically mention their Figure 9, with the proposed algorithm and suggestions for utilization of multiple diagnostic imaging modalities as well as Table 1, with a summary of diagnostic strengths and weaknesses for the noninvasive diagnostic modalities reviewed in this paper.…”

Each Nuclear Cardiology lab should have its own lower limit of normal for functional parameters: True or False?

“…Lung-heart ratios [55% for TI-201 and [44% for Tc-99m tracers, and transient ischemic dilatation (TID) help better detect patients with severe CAD on MPI. 12 However, in the setting of normal MPI, increased TID ratio has a low prevalence and a poor predictive accuracy and should not be considered as a marker of high risk CAD. 13 Multiple studies have shown the importance of identifying a normal limit for functional parameters obtained by GSPECT in different geographic regions and different ethnicities.…”

Living on a Thread: A Case of Critical Left Main Coronary Artery Disease With an Unusual Presentation

“…It is associated with a poor prognosis and has a detrimental effect on the heart [ 5 ]. Cardiac troponin measurements are considered the preferred diagnostic markers of acute myocardial injury [ 6 ].…”