Hiroyasu Ueda

Reflection in the arterial system and the risk of coronary heart disease.

BACKGROUND Although it was reported that the augmentation index and inflection time are closely related to reflection in the arterial system and large artery function, it is not known whether these indices of the ascending aortic pressure waveform increase the risk of coronary heart disease (CHD). The purpose of this study was to evaluate whether the aortic reflection of the ascending aortic pressure waveform is related to an increased risk of CHD. METHODS We enrolled 190 men and women who had chest pain, normal contractions, no local asynergy, and no history of myocardial infarction. We measured the ascending aortic pressure using a fluid-filled system. The inflection time was defined as the time interval from initiation of a systolic pressure waveform to the inflection point. We investigated the association between the inflection time and augmentation index of the ascending aorta and the risk of CHD. RESULTS Both the inflection time and augmentation index were associated with an increased risk of CHD. The crude prevalence rates of CHD were 66.0% for the shortest quartile and 10.6% for the longest quartile of the inflection time, and 17.0% for the lowest quartile and 40.4% for the highest quartile of the augmentation index. The multiple-adjusted odds ratio of CHD was 30.8 (95% confidence interval [CI] 7.43-128.05) for the shortest quartile of the inflection time compared with the longest quartile and was 3.82 (95% CI 1.26-11.59) for the highest quartile of the augmentation index compared with the lowest quartile. CONCLUSIONS The augmentation index and inflection time were associated with an increased risk of CHD.

Pulsatility of ascending aortic blood pressure waveform is associated with an increased risk of coronary heart disease

BACKGROUND Although it was reported that pulse pressure of the peripheral artery could differentiate patients with coronary heart disease (CHD) from those without CHD, it is not known whether pulsatility of the ascending aortic pressure waveform differentiates patients with CHD from those without CHD. The purpose of this study was to evaluate whether the pulsatility of ascending aortic pressure is associated with an increased risk of CHD. METHODS For this study, we enrolled 293 subjects who had chest pain, normal contractions, no local asynergy, and no history of myocardial infarction. We measured the ascending aortic pressure using a fluid-filled system. To quantify the relative magnitude of the pulsatile to mean artery pressure, we normalized the pulse pressure to the mean pressure and referred to this value as the fractional pulse pressure (PPf). We investigated the association between the PPf and the risk of CHD. RESULTS The PPf of the ascending aorta was associated with an increased risk of CHD. The multiple-adjusted odds ratio of CHD was 2.93 (95% CI, 1.44 to 5.94) for the middle tertile of the PPf level and was 3.93 (95% CI, 1.74 to 8.85) for the highest tertile compared with the lowest tertile. CONCLUSION Ascending aortic pulsatility is related to an increased risk of CHD.

Inflection Point of Ascending Aortic Waveform Is a Powerful Predictor of Restenosis After Percutaneous Transluminal Coronary Angioplasty

BACKGROUND Although it was reported that the pulsatility of ascending aortic pressure is closely related to restenosis after percutaneous transluminal coronary angioplasty (PTCA), it is not known whether the reflection period of ascending aortic pressure can predict restenosis after PTCA. The purpose of this study was to evaluate whether reflection in the arterial system can be used to predict restenosis after PTCA. METHODS We used the inflection point as the reflection period index and measured the coronary artery diameter, aortic pressure, and inflection time before PTCA. We defined the inflection time as the time interval from the initiation of systolic pressure waveform to the inflection point. We prospectively investigated the effect of inflection time in relation to the subsequent risk of restenosis after PTCA in patients with coronary artery disease. RESULTS Crude cumulative incidence rates of restenosis were 74.1% for the lowest, 33.3% for the middle, and 26.1% for the highest tertile of inflection point levels. After adjustments for age, gender, smoking habits, hypertension, type 2 diabetes, hypercholesterolemia, old myocardial infarction, vessel location, post-minimal lumen diameter, heart rate, and ejection fraction, the odds ratio of restenosis was 6.99 (95% confidence interval, 1.54 to 31.7) for the lowest tertile of the inflection time level compared with the highest tertile level. CONCLUSIONS Inflection time is a powerful predictor of restenosis after PTCA.

Low fractional diastolic pressure in the ascending aorta increased the risk of coronary heart disease.

Although the fractional pulse pressure in the ascending aorta is related to the occurrence of coronary heart disease (CHD) and restenosis after percutaneous transluminal coronary angioplasty, the relative values of diastolic pressure in the ascending aorta at the onset of CHD have not been reported. The purpose of this study was to evaluate whether the relative values of diastolic pressure are associated with the risk of CHD. For this study, we enrolled 406 patients with chest pain, normal contractions, no local asynergy, and no history of myocardial infarction. We measured the ascending aortic pressure using a fluid-filled system. To quantify the relative diastolic pressure, we normalised the diastolic pressures to the mean pressure and referred to this value as the fractional diastolic pressure (FDP). We investigated the association between the FDP and the risk of CHD. Low FDP in the ascending aorta was associated with an increased risk of CHD. The multiple-adjusted odds ratio of CHD was 1.68 (95% CI, 0.67–4.22) in FDP for the middle tertile of the level. The multiple-adjusted odds ratio of CHD was 2.20 (1.16–4.75) in FDP for the lowest tertile compared with the highest tertile. FDP was associated with the risk of CHD.

Ascending fractional pulse pressure closely relating to large artery function.

It is not known whether ascending fractional pulse pressure (PPf) is related to large artery function. This study was to evaluate whether PPf is associated with large artery function by augmentation index. A total of 190 subjects were enrolled (age range: 50 to 78 years) who had normal contractions, no local asynergy, and no history of myocardial infarction. The ascending aortic pressure was measured using a fluid-filled system. To quantify the relative magnitude of the pulsatile to mean artery pressure, we normalised the pulse pressure to the mean pressure and referred to this value as PPf and the association between the PPf and the augmentation index was investigated. Augmentation index showed significant associations with PPf by univariate analysis (R = 0.690, P < 0.001). The associations between PPf and the factors influencing large artery function were examined by multivariate analysis, and PPf revealed significant associations with age, mean aortic pressure, heart rate and type 2 diabetes (R2 = 0.477, P < 0.001). The results were that ascending aortic PPf is closely associated with large artery function detected by augmentation index.

Pulsatility of brachial artery pressure is associated with an increased risk of coronary artery disease in men.

Objectives The purpose of this study was to evaluate whether the pulsatility of brachial artery pressure is related to an increased risk of coronary artery disease (CAD). On the basis of vascular mechanics, we recently reported that relative pulse pressure can predict the occurrence of restenosis after percutaneous transluminal coronary angioplasty. We also hypothesized that relative pulse pressure of the brachial arterial pressure waveform is associated with an increased risk of CAD. Design A cross-sectional study. Patients We enrolled 172 men who had the same cardiac performances. Main outcome measures We measured their brachial artery pressures with a sphygmomanometer. To quantify the relative magnitude of the pulsatility to diastolic pressure, we made use of the ratio of pulse pressure to diastolic pressure (PP/DP). We investigated the effects of the PP/DP in relation to the risk of CAD. Results PP/DP was associated with an increased risk of CAD. The prevalence rates of significant stenosis were 28.1% for the lowest, 43.1% for the middle and 49.1% for the highest tertile of PP/DP levels. The age-adjusted odds ratio of CAD was 2.23 (95% confidence interval 0.98–5.04) for the middle tertile of the PP/DP level and 2.55 (1.10–5.93) for the highest tertile compared with the lowest tertile. Conclusions The pulsatility of the brachial artery pressure was associated with an increased risk of CAD.

High-normal blood pressure is associated with new-onset electrocardiographic left ventricular hypertrophy.

Whether high–normal blood pressure (BP) is a predictor of new-onset electrocardiographic (ECG)-left ventricular hypertrophy (LVH) is not known. A total of 4112 subjects who underwent physical examinations were enrolled in this study. BP was measured on entry. Standard 12-lead ECG was recorded at initial evaluation and 3 years later. BP categories were defined on the basis of the 2013 European Society of Hypertension/European Society of Cardiology guidelines. Of the 4112 subjects, 133 developed ECG-LVH 3 years later. Crude cumulative prevalence rates of new-onset ECG-LVH were 2.0% for the optimal BP group, 3.2% for the normal BP group, 5.1% for the high–normal BP group and 5.0% for the hypertension group. After adjustment for age, gender, body mass index, smoking, low-density lipoprotein cholesterol, log-transformed high-density lipoprotein cholesterol, log-transformed triglycerides, estimated glomerular filtration rate, haemoglobin A1c, haemoglobin, uric acid and antihypertensive medication use, compared with the optimal BP group, the odds ratios of new-onset ECG-LVH for the normal BP, high–normal BP and hypertension groups were 1.52 (95% confidence interval (CI): 0.93–2.49, P=0.094), 2.38 (95% CI: 1.40–4.03, P=0.001) and 2.44 (95% CI: 1.43–4.18, P=0.001), respectively. Even high–normal BP was significantly associated with the presence of new-onset ECG-LVH.

Intravenous Nicorandil Can Reduce QT Dispersion and Prevent Bradyarrhythmia During Percutaneous Transluminal Coronary Angioplasty of the Right Coronary Artery

Background: Nicorandil, a potassium channel opener, is used for the treatment of angina pectoris and has a pharmacologic preconditioning effect. This study evaluated whether intravenous nicorandil reduces QT dispersion and prevents bradyarrhythmia during percutaneous transluminal coronary angioplasty (PTCA) of the right coronary artery. Methods: A historical cohort study on the effect of nicorandil on QT dispersion and bradyarrhythmia was conducted. Fifty patients who underwent PTCA of the right coronary artery were enrolled. The patients were divided into a nicorandil (n = 25) group and control group (n = 25). Nicorandil was injected at 4 mg/h continuously 1 hour before PTCA in the nicorandil group. QT dispersion was measured at 1 hour before PTCA (baseline), immediately before PTCA, and 1 minute after the initiation of the first balloon inflation. Results: QT dispersion at 1 minute after the initiation of the first balloon inflation in the control group increased significantly (QT dispersion: 37.1 ± 17.8 msec and 21.7 ± 12.2 msec, respectively, P < .001 vs baseline in the control group), and this was larger than at 1 minute after the initiation of the first balloon inflation in the nicorandil group (QT dispersion: 37.1 ± 17.8 msec and 20.8 ± 9.4 msec, respectively, P < .001). By two-way repeated measures analysis of variance, there were significant interactions between the time factor and the grouping factor in QT dispersion (P < .001). Bradyarrhythmia was observed in 6 patients in the control group, but none was observed in the nicorandil group. Conclusions: Intravenous nicorandil reduces QT dispersion and prevents bradyarrhythmia during PTCA of the right coronary artery.

Takotsubo Cardiomyopathy in Two Patients without Any Cardiac Symptom on Maintenance Hemodialysis

Takotsubo cardiomyopathy is a disorder characterized by left ventricular apical ballooning and electrocardiographic changes in the absence of coronary artery disease. While reversible in many cases, the mechanism of this disorder remains unclear. The most frequent clinical symptoms of takotsubo cardiomyopathy on admission are chest pain and dyspnea, resembling acute myocardial infarction. Here, we describe two cases of takotsubo cardiomyopathy without chest pain or dyspnea in patients on maintenance hemodialysis. The asymptomatic nature of these two cases may be due to the patients being on hemodialysis. Periodic electrocardiograms (ECG) may be helpful in screening this population for asymptomatic takotsubo cardiomyopathy and in evaluating its incidence.

Relation of Estimated Glomerular Filtration Rate to the Presence of Coronary Plaque and Obstructive Coronary Artery Disease in a Zero or Low Coronary Artery Calcium Score

Objectives: Although renal dysfunction is associated with the presence of atherosclerosis, little is known about the relationship between reduced estimated glomerular filtration rate (eGFR) and the presence of atherosclerosis detected by coronary computed tomographic angiography (CCTA). This study evaluated the relation of eGFR to the presence of coronary plaque and obstructive coronary artery disease (CAD) in patients with a zero or low coronary artery calcium score (CACS). Methods: Coronary artery calcium scoring and CCTA were performed with CT scanners. Serum creatinine was measured before CCTA, and GFR was estimated. A total of 720 patients with a CACS ≤10 were enrolled. Results: Coronary plaque was detected in 118 patients. Of the 118 patients, 36 had a diagnosis of obstructive CAD. The multiple-adjusted odds ratios of presenting with coronary plaque and obstructive CAD were 1.82 (95% CI 1.06-3.12, p = 0.030) and 1.79 (95% CI 0.71-4.49, p = 0.217) for the lowest tertile of eGFR compared with the highest tertile, respectively. Conclusions: Lower eGFR levels were associated with the presence of coronary plaque in patients with a zero or low CACS. However, the association between eGFR and the presence of obstructive CAD was not statistically significant.