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Objectives: The feasibility of detecting persistent regional left ventricular abnormal relaxation due to myocardial ischemia using strain echocardiography several minutes after exercise was investigated., Methods: Consecutive 27 patients (mean age 65 +/- 9 years, 21 males, 6 females) with suspected coronary artery disease were enrolled. Strain echocardiographic images were acquired at the mid segments of the left ventricular wall before and 5 min after exercise in the apical long-axis, two-chamber and four-chamber views. Strain curves were obtained at each segment, and peak values of strain at the closure of aortic valve (A) and at one third of diastolic duration (B) were measured. Strain diastolic index (SDI) was calculated as (A - B)/A X 100%. The ratio of SDI before exercise to that after exercise was defined as the SDI ratio and compared with exercise thallium-201 single photon emission computed tomography (SPECT) as the reference standard to detect myocardial ischemia., Results: A total of 162 segments were evaluated. Based on the results of exercise SPECT, 119 segments were classified as non-ischemic segments, and 43 as ischemic segments. Ischemic segments showed significant decreases in SDI before and after exercise, whereas non-ischemic segments showed no significant differences in SDI before and after exercise. SDI ratio was significantly decreased in ischemic segments, but not in non-ischemic segments. SDI ratio with a cut off value of 0.51 had a sensitivity of 91% and a specificity of 89% to detect myocardial ischemia in the receiver-operating characteristics. Conclusions. Strain echocardiography can provide quantitative assessment of myocardial ischemia by detecting post-ischemic regional left ventricular delayed relaxation even 5 min after exercise.

An 80-year-old woman underwent aortic valve replacement with Freestyle stentless prosthetic valve for the stenosis. Four months later, she was admitted with myocardial ischemia. Coronary angiography revealed severe stenosis in the ostium of both right and left coronary arteries. Coronary artery bypass grafting was performed. One year later, percutaneous coronary intervention was carried out for the bilateral coronary arteries because of unstable angina. Intravascular ultrasonography demonstrated localized, membranous, homogeneous, and severe stenoses in the ostium of the right and left coronary arteries. Histological examination of a specimen taken by directional coronary atherectomy showed intimal hypertrophy, mucinous degeneration, and hyaline degeneration without reactive change. There were no findings of atherosclerosis. These clinical, angiographical histological and intravascular ultrasonography findings suggest that the immunological reaction to the heterograft was the mechanism of the bilateral ostial coronary arteries stenoses in the present case. The possibility of immunological reaction after aortic valve replacement with heterograft should be considered. There have been no report on intravascular echocardiographic and histological findings.

Objectives: Development of left ventricular hypertrophy in severe aortic stenosis is associated with coronary microcirculatory dysfunction, as demonstrated by impaired coronary flow reserve. Recently, coronary flow reserve can be assessed noninvasively by transthoracic Doppler echocardiography (TTDE). This study assessed the relationship between coronary flow reserve obtained by TTDE and the hemodynamic parameters and left ventricular mass index in patients with aortic stenosis., Methods: Consecutive 29 patients (15 men, 14 women, mean age 72 +/- 11 years) with isolated mild to severe aortic stenosis were studied using TTDE to assess coronary flow reserve. Peak transvalvular pressure gradient across the aortic valve (peak AVG) and aortic valve area were measured by TTDE. Left ventricular mass index was measured by echocardiography., Results: There were significant correlations between coronary flow reserve and peak AVG (r = -0.570, p = 0.001), left ventricular mass index (r = -0.620, p < 0.001), aortic valve area (r = 0.740, p < 0.001), and left ventricular rate pressure product (r = -0.660, p < 0.001). Multiple regression analysis showed that aortic valve area and peak AVG were independent factors for coronary flow reserve (p < 0.001, p = 0.048)., Conclusions: Impairment of coronary flow reserve in patients with aortic stenosis is related to aortic valve area and peak AVG, rather than the degree of left ventricular hypertrophy.

Objectives: This study assessed the relationship between coronary flow reserve and functional recovery of left ventricular wall motion in patients with tako-tsubo-like transient left ventricular dysfunction., Methods: Coronary flow reserve was measured using the Doppler guide wire technique in the left descending coronary artery in nine consecutive patients (three men, six women, mean age 71 +/- 11 years) with tako-tsubo-like transient left ventricular dysfunction. Regional wall motion was analyzed to estimate anterior wall motion score index (anterior WMSI) by transthoracic echocardiography on admission and 3 weeks after the onset of symptoms., Results: Anterior WMSI was 2.2 +/- 0.4 on admission and improved to 1.4 +/- 0.5 at 3 weeks later (p < 0.001). Coronary flow reserve on admission was not correlated to the anterior WMSI on admission (r = 0.19, p = 0.63). However, coronary flow reserve on admission was correlated to the improvement in anterior WMSI (r = 0.74, p = 0.02)., Conclusions: Coronary microcirculation is damaged in acute phase of tako-tsubo-like transient left ventricular dysfunction. The severity of coronary microvascular dysfunction influences the degree of left ventricular wall motion recovery.