Browsing by Author "Panic, Milos (6603593761)"

In a few patients with acute proximal thrombotic occlusion of the left anterior descending coronary artery (LAD), tall ischemic T waves never evolve into ST-segment elevation. This was recently inaccurately reported as a "novel sign" of proximal LAD occlusion. It has been speculated that the absence of ST-segment elevation could be attributed to the large area of transmural ischemia, the anatomic variant of Purkinje fibers, or to lack of activation of sarcolemal adenosine triphosphate-potassium channels. This electrocardiographic picture was recently explained by changes in the subendocardial but not in the epicardial action potential, suggesting subendocardial ischemia as the underlying mechanism. We present a patient with thrombotic lesion of proximal LAD, static precordial ST-segment depression, and tall T waves who underwent primary percutaneous intervention and stent placement. Surprisingly, total thrombotic stent occlusion on the following day was associated with ST-segment elevation in precordial leads, indeed supporting the concept of the regional subendocardial ischemia that was first described more than a decade ago.

Aims We sought to determine the prevalence of overt and subclinical LV dysfunction in patients with critical left anterior descending coronary artery (LAD) stenosis but without a history of myocardial infarction and to compare diagnostic value of routine echocardiographic parameters with myocardial strain analysis for detection of critical LAD stenosis. Methods and results We retrospectively studied 269 patients with suspected coronary artery disease (CAD)-209 consecutive patients with critical LAD stenosis and 60 consecutive patients with atypical chest pain and without CAD. Conventional visual assessment of LV asynergy in the LAD territory was compared with global, regional, and segmental peak systolic longitudinal strain (PSLS) parameters derived by two-dimensional speckle tracking echocardiography (2D STE).Wall motion abnormalities in the LAD territory were found in 41% of patients with critical LAD stenosis, whereas, depending on the cut-off value, global longitudinal strain (GLS)was impaired in 42-69% of patients. GLS with an area under the receiver operating characteristic curve (AUC) of 0.85 showed better discriminative power for detecting critical LAD stenosis than conventionalwall motion score index(AUC0.73, P < 0.05, for the difference between the AUCs). PSLS valueswere significantly lower in basal and midventricular segments supplied by critically narrowed LAD, particularly if they also appeared dysfunctional on visual assessment. Conclusions Detection of subclinical LV dysfunction by 2D STE might improve identification of patients with critical LAD stenosis, although visually apparent regional LV dysfunction in theLADterritory is not uncommon finding in this subset of patients. © The Author 2015.