冠動脈ステント内再狭窄に対する冠動脈形成術の周術期心筋傷害への検討

広島大学(Hiroshima University)博士(医学)Doctor of Philosophy in Medical Sciencedoctora

Thallium-201 gated single-photon emission tomography for assessing left ventricular volumes and function in patients with aortic valve stenosis: Comparison with echocardiography as the reference standard

Aortic valve stenosis (AS) is characterized by chronic left ventricular pressure overload, leading to left ventricular hypertrophy (LVH). We assessed correlations in left ventricular volumes and function between echocardiography and quantitative gated SPECT (QGS) in patients with AS. The study population consisted of 28 patients with AS defined as a peak velocity of > 3.0 m/s and 28 age- and sex-matched control subjects. Patients with AS had a peak pressure gradient of 73.4 ± 24.5 mm Hg and a larger LVM index compared to control subjects (115.5 ± 29.2 g/m2 vs 78.3 ± 12.1 g/m2, p < 0.01). There were good correlations in end-diastolic volume and end-systolic volume between echocardiography and QGS in patients with AS as well as control subjects. Bland–Altman plot for end-systolic volume showed a significant negative slope of − 0.51 in patients with AS. There was a good correlation in ejection fraction between the 2 methods in patients with AS as well as control subjects. However, Bland–Altman plots showed significant negative slopes of − 0.40 in patients with AS and − 0.74 in control subjects. Our data suggested that QGS was a useful method for assessing left ventricular volumes and function even in patients with AS. Cardiologists should recognize its specific characteristics

Poor R-wave progression and myocardial infarct size after anterior myocardial infarction in the coronary intervention era

Regeneration of R-wave or disappearance of Q-wave sometimes occurs after myocardial infarction (MI) especially in the coronary intervention era. We assessed the impact of poor R-wave progression (PRWP) or residual R-wave in precordial leads on myocardial infarct size in patients with prior anterior MI treated with coronary intervention. Fifty-three patients with prior anterior MI and 20 age- and sex-matched patients without underwent electrocardiogram (ECG), myocardial perfusion single photon emission tomography (SPECT) and echocardiography. Poor R-wave progression (PRWP) was defined as RV3 ≤ 3 mm. R-wave was significantly lower in all precordial leads in patients with prior anterior MI than those without. Among 53 patients with prior anterior MI, 33 patients had PRWP, and the remaining 20 patients did not. Patients with PRWP had larger sum of defect score (17.5 ± 8.6 vs 7.6 ± 10.3, p < 0.001) and lower left ventricular ejection fraction (LVEF) (46.1 ± 9.8% vs 55.2 ± 12.9%, p < 0.01) than those without. The sum of R-wave in lead V1 to V6 inversely correlated with the sum of defect score (r = − 0.56, p < 0.001), and positively correlated with LVEF (r = 0.45, p < 0.001). Our data suggested that residual R-wave during the follow-up period reflected myocardial infarct size and left ventricular systolic function well in patients with prior anterior MI treated with coronary intervention

Electrocardiographic characteristics in the underweight and obese in accordance with the World Health Organization classification

Objective: It is clinically important to recognize how the underweight or obese affects electrocardiogram (ECG). We assessed the effects of body mass index (BMI) on QRS axis or R-wave heights. Methods: From daily outpatient electrocardiograms with sinus rhythm, 203 were selected. The patients were classified into four groups: underweight (<18.5 kg/m2), normal weight (18.5–24.9 kg/m2), overweight (25–29.9 kg/m2) and obese (≥30 kg/m2). Results: With increasing BMI, QRS axis shifted rightward to leftward. There was a significant inverse correlation between BMI and QRS axis (r = −0.60, p < 0.001). Multivariate linear regression analysis among age, female, BMI, hypertension, left ventricular internal dimension and left ventricular mass (LVM) revealed that BMI was an independent determinant of QRS axis (β = −0.52, p < 0.0001). Although LVM increased with increasing BMI, R-wave heights in leads V4-5 were similar among the underweight, normal weight and overweight. R-wave heights in leads V4-5 were significantly lower paradoxically in the obese than other groups. With increasing BMI, Sokolow–Lyon index corrected by LVM decreased progressively. Conclusions: Our results suggest that the underweight or obese is strongly associated with QRS axis or R-wave heights

Poor R-wave progression and myocardial infarct size after anterior myocardial infarction in the coronary intervention era

Background: Regeneration of R-wave or disappearance of Q-wave sometimes occurs after myocardial infarction (MI) especially in the coronary intervention era. We assessed the impact of poor R-wave progression (PRWP) or residual R-wave in precordial leads on myocardial infarct size in patients with prior anterior MI treated with coronary intervention. Methods: Fifty-three patients with prior anterior MI and 20 age- and sex-matched patients without underwent electrocardiogram (ECG), myocardial perfusion single photon emission tomography (SPECT) and echocardiography. Poor R-wave progression (PRWP) was defined as RV3 ≤ 3 mm. Results: R-wave was significantly lower in all precordial leads in patients with prior anterior MI than those without. Among 53 patients with prior anterior MI, 33 patients had PRWP, and the remaining 20 patients did not. Patients with PRWP had larger sum of defect score (17.5 ± 8.6 vs 7.6 ± 10.3, p < 0.001) and lower left ventricular ejection fraction (LVEF) (46.1 ± 9.8% vs 55.2 ± 12.9%, p < 0.01) than those without. The sum of R-wave in lead V1 to V6 inversely correlated with the sum of defect score (r = −0.56, p < 0.001), and positively correlated with LVEF (r = 0.45, p < 0.001). Conclusion: Our data suggested that residual R-wave during the follow-up period reflected myocardial infarct size and left ventricular systolic function well in patients with prior anterior MI treated with coronary intervention

Thallium-201 gated single-photon emission tomography for assessing left ventricular volumes and function in patients with aortic valve stenosis: Comparison with echocardiography as the reference standard

Background: Aortic valve stenosis (AS) is characterized by chronic left ventricular pressure overload, leading to left ventricular hypertrophy (LVH). We assessed correlations in left ventricular volumes and function between echocardiography and quantitative gated SPECT (QGS) in patients with AS. Methods and results: The study population consisted of 28 patients with AS defined as a peak velocity of >3.0 m/s and 28 age- and sex-matched control subjects. Patients with AS had a peak pressure gradient of 73.4 ± 24.5 mm Hg and a larger LVM index compared to control subjects (115.5 ± 29.2 g/m2 vs 78.3 ± 12.1 g/m2, p < 0.01). There were good correlations in end-diastolic volume and end-systolic volume between echocardiography and QGS in patients with AS as well as control subjects. Bland–Altman plot for end-systolic volume showed a significant negative slope of −0.51 in patients with AS. There was a good correlation in ejection fraction between the 2 methods in patients with AS as well as control subjects. However, Bland–Altman plots showed significant negative slopes of −0.40 in patients with AS and −0.74 in control subjects. Conclusions: Our data suggested that QGS was a useful method for assessing left ventricular volumes and function even in patients with AS. Cardiologists should recognize its specific characteristics