Electrocardiographic ST-Segment Elevation and Changes in the Regional Work of the Left Ventricle During Coronary Angioplasty

Abstract

ecause coronary blood flow is abruptly interrupted during percutaneous transluminal coronary angioplasty (PTCA), the patient experiences transient regional myocardial ischemia with this procedure. Therefore, PTCA is useful for studying the effects of acute regional myocardial ischemia on left ventricular (LV) function.Regional myocardial work is used to analyze regional dysfunction of the LV in patients with coronary artery disease (CAD), [1][2][3][4] and in the present study we used the method proposed by Nakano and Sugawara et al, [1][2][3][4][5][6][7][8][9] which is based on the simultaneous measurement of LV pressure and LV regional wall thickness to give regional work normalized to unit volume of myocardium in true unit of work (mJ/cm 3 ).The purpose of this study was to assess the change in regional work of the LV wall and correlate it with STsegment elevation during PTCA to the proximal left anterior descending artery (LAD). Methods PatientsTwenty-five patients (18 men, 7 women; age (mean ± SD), 62±10 years) with stable angina pectoris were recruited. They were scheduled for PTCA of a significant stenosis in the proximal LAD. All patients had single-vessel CAD without angiographic evidence of collateral circulation and with normal wall motion assessed by both 2-dimensional echocardiography and left ventriculography. Patients with unstable angina, recent or previous myocardial infarction, arrhythmia (atrial fibrillation, etc), valvular diseases, or other cardiac diseases were excluded. Moreover, patients with systemic diseases (hypertension, diabetes mellitus, etc) that would influence cardiac function were also excluded. All the patients underwent exercise 201 Tl myocardial scintigraphy, which confirmed that they had myocardial ischemia in the LAD region. No patients received -adrenergic blocking agents, calcium channel blocking agents or other cardiovascular drugs within 24 h of beginning the study. We explained the content of the study to all the patients and written informed consent was obtained from them. Electrocardiogram (ECG)A 12-lead ECG monitored and recorded continuously on paper at a speed of 25 mm/s before, during and after balloon deflation. It was a standard 12-lead ECG except for leads V2 and V3, which were slightly below the usual location because of the simultaneous recording of echocardiography. Calibration was performed at the beginning of the procedure (1 mV = 10 mm). ST-segment elevation was measured at 80 ms after the J point. AngiographyCoronary angiography and left ventriculography were performed in the usual fashion several days before PTCA. Left ventriculography was performed in the 30°right anterior oblique view by injection of 30 ml of contrast medium This study evaluated the reduction in regional work of the left ventricle caused by acute myocardial ischemia during coronary angioplasty, and correlated it with ST-segment elevation. Regional work of the left ventricular myocardium, which is derived from a stress -strain loop, is a useful index of the function of a diseased heart...

Delayed recovery of left ventricular regional work after coronary angioplasty in patients with opposite wall old myocardial infarction

“…[1][2][3] In many of these patients, the regional work of the nonischemic area gradually increased during balloon inflation.…”

“…Recently, sequential changes in LV regional function during PTCA have been reported in patients with normal LV function. [1][2][3] However, no prior studies have assessed these changes during PTCA in patients having a reduced LV function. Regional LV function was previously evaluated by calculating regional work using the relationship between mean wall stress and strain (the natural logarithm of the reciprocal of wall thickness).…”

“…Regional LV function was previously evaluated by calculating regional work using the relationship between mean wall stress and strain (the natural logarithm of the reciprocal of wall thickness). [1][2][3][4][5][6][7][8][9][10][11][12][13] In this study, we examined the sequential changes of LV regional work from the beginning of balloon inflation to just after balloon deflation of the left anterior descending coronary artery (LAD) in patients with or without posterior OMI, and finally clarified the characteristics of the sequential changes of LV regional work during PTCA in patients having a reduced LV function.…”

Nicorandil Infusion Leads to Good Recovery From Ischemia of Left Ventricular Regional Work in Comparison With Nitroglycerin.

“…[19][20][21][22][23] We used their concept to assess changes in left ventricular (LV) RW during PTCA, and compared the effects of NR and nitroglycerin (NG) on the recovery of RW from ischemia.…”