Change in environmental bacterial flora in a new hospital building.

Microbial surveillance of environmental bacteria was performed in order to study the microbial changes in a newly established hospital building. Airborne bacteria and surface-associated bacteria on floors and sinks were systematically collected between 2002 and 2005. The number of isolates obtained from frequently used floors was significantly higher than that obtained from those floors used less often. A significant increase in Staphylococcus aureus, the appearance of Pseudomonas aeruginosa, and changes among species of Gram-negative bacilli were observed 8-11 months after the new building had been opened. Furthermore, pulsed-field gel electrophoresis (PFGE) typing of meticillin-resistant S. aureus (MRSA) and P. aeruginosa showed that strains of the same PFGE groups were isolated from different sinks, floors and the adjoining old buildings. The number of MRSA isolates obtained from the new building increased as time passed. The sinks from which P. aeruginosa strains of the same PFGE type were isolated are connected by the same drainage pipe. Human movement has considerable effects on bacterial flora and their subsequent spread.

[Procedure and problem for short-term outcomes on off-pump coronary artery bypass grafting].

We performed off-pump coronary artery bypass grafting (CABG) in all cases without reoperation case from July, 2002. Advantage of off-pump CABG versus on-pump CABG which is reduced a number of perioperative complication and early patients recovery was previously demonstrated. In our institute, the mean number of grafts per patients was 4.7 +/- 1.3, and the rate of using arterial grafts was 99.5% in all cases without minimally invasive direct coronary artery bypass (MIDCAB). The mean hospital stay after operation was 10.8 +/- 2.8. It was shorted remarkably in comparison with on-pump CABG; 19.4 +/- 6. Furthermore, sever complication was not occurred in any cases after operation though high risk cases were increased. In the early cases, atrial fibrillation complicated frequently (32%), but using after magnesium sulfate it was remarkably decreased (8.4%). On the other-hand, attention is necessary for the infection caused by the increase of high risk patients. Therefore, we used vancomycin (VCM) at these cases from the viewpoint of prevention. Recently, we performed remnant omental transfer for the sever diabetes mellitus case which was used bilateral internal thoracic artery on CABG. It learned to get the early recovery which was necessary for the off-pump CABG by the above additional treatment.

[Survival after oozing type cardiac rupture associated with subepicardial aneurysm evaluated by echocardiography: a case report].

A 64-year-old woman was admitted to our hospital with acute myocardial infarction. She underwent emergent percutaneous transluminal coronary angioplasty. Transthoracic echocardiography revealed mild pericardial effusion on the third day. Pericarditis or cardiac rupture were suspected, so transthoracic echocardiography was repeated serially. On the sixth day, transthoracic echocardiography showed increasing pericardial effusion and abrupt interruption of the apical myocardium of the left ventricle and intact epicardial imaging with systolic expansion. The diagnosis was oozing type cardiac rupture of a subepicardial aneurysm. Surgical treatment was successful and the accuracy of the echocardiographic diagnosis was established.

Coronary artery bypass grafting with cardiopulmonary bypass is safe and contributes to favorable long-term results.

The aim of this study was to determine the indication for minimally invasive direct coronary artery surgery based on the operative and long-term results of conventional coronary artery bypass grafting with cardiopulmonary bypass. Operative results: The subjects included 505 patients who underwent isolated elective coronary artery bypass grafting with cardiopulmonary bypass from January 1995 through August 1999. The mean age at the time of surgery was 61.9 and the mean number of grafts per patient was 2.6. Long-term results: From January 1984 to December 1995, a total of 907 patients received coronary artery bypass grafting with cardiopulmonary bypass using the internal thoracic artery to the left anterior descending artery with or without saphenous vein grafts to other coronary arteries. The rates of complete and incomplete revascularization were 69.3% (n = 629) and 30.7% (n = 278), respectively. Mean follow-up was 5.95+/-3.0 years. The operative results revealed low output syndrome occurred in 14 patients (2.8%), perioperative myocardial infarction with the appearance of new Q-waves in 5 (1.0%), renal failure requiring transient dialysis in 16 (3.2%), stroke with persistent sequelae in 5 (1.0%), and mediastinitis in 5 (1.0%). Two patients (0.4%) died in the hospital. The long-term results for the 907 patients revealed the 10-year actuarial survival, 10-year cardiac death free, and 10-year cardiac event free rates were 85.7%, 94.1%, and 77.3%, respectively. The 10-year survival rates was 88.4% among patients receiving complete revascularization and 79.3% among those receiving incomplete revascularization (p = 0.0334). The 10-year cardiac death free rate among patients undergoing complete revascularization was 96.3% and 88.7% among those receiving incomplete revascularization (p = 0.0016). The 10-year cardiac event free rates were 82.3% and 67.9%) among patients undergoing complete and incomplete revascularization, respectively (p = 0.0118). In view of the favorable operative and long-term results of conventional coronary artery bypass grafting, especially complete revascularization, we conclude that minimally invasive direct coronary artery grafting is an appropriate treatment for multi-vessel disease in carefully selected patients at a high risk for stroke and major comorbidities due to old age.

Coronary artery bypass grafting in patients on chronic hemodialysis: surgical outcome in diabetic nephropathy versus nondiabetic nephropathy patients.

BACKGROUND: The presence of diabetes mellitus adversely affects the late survival of patients undergoing coronary artery bypass grafting (CABG). The purpose of this study is to clarify the role of diabetic nephropathy on outcomes of a group of patients on chronic hemodialysis undergoing CABG. METHODS: Between April 1984 and July 1999, 45 patients on chronic hemodialysis underwent CABG. Forty-three had conventional CABG and 2 had off-pump CABG. There were 37 males and 8 females, and the mean age was 57 years (43 to 76 years). Twenty-one patients had diabetic nephropathy (group D) and 24 had nondiabetic nephropathy (group ND). Early and late results were determined in both groups. RESULTS: Early outcome was not significantly different between the groups. There was no hospital mortality, stroke, or requirement for prolonged mechanical ventilation (>24 hours) in either group. No patients in group D, and only 1 (4.2%) in group ND had low cardiac output syndrome. The difference in the incidence of arrhythmias (23.8% in group D and 25% in group ND), wound infections (9.5% in group D and 8.3% in group ND), and delayed tamponade (5% in group D and 12.5% in group ND) was not statistically significant. However, late results differed significantly between the two groups. Actuarial survival (Kaplan-Meier) at 5 and 9 years was 22.9% and 11.5% in group D and 89.1% and 45.7% in group ND (p = 0.01), respectively. Similarly, the cardiac event-free rate at the same intervals was 50.4% and 0% for group D and 100% and 65.8% for group ND (p = 0.001), respectively. CONCLUSIONS: Using present technology, CABG can be done in patients on chronic hemodialysis with acceptable early mortality and morbidity. Late results in patients with diabetic nephropathy on hemodialysis are not as favorable as their nondiabetic cohort.

[Coronary artery dissection following angioplasty evaluated by fractional flow reserve: report of three cases].

Fractional flow reserve was measured in three patients with coronary artery dissection occurring after percutaneous coronary intervention. In Case 1, fractional flow reserve decreased from 0.88 to 0.73 and angiography showed coronary artery dissection 20 min after balloon angioplasty. In Case 2, angiography showed good results, but the fractional flow reserve decreased to a low value(0.69). Intravascular ultrasonography revealed dissection. In Case 3, angiography clearly showed dissection, but fractional flow reserve remained high(0.91). Stent implantation was performed in all three patients, but might not have been necessary in Case 3. Dissection with low or diminished fractional flow reserve value may cause a pressure gradient in the true lumen. Stent implantation is necessary in such cases. On the other hand, cases of dissection in which the fractional flow reserve value is maintained may also cause a pressure gradient in true lumen, but stent implantation may not be necessary. Fractional flow reserve measurements may be useful for the assessment of coronary artery dissection and evaluating the indications for stent implantation.

Cloning and expression of a cDNA encoding human inositol 1,4,5-trisphosphate 3-kinase C.

Inositol 1,4,5-trisphosphate [Ins(1,4,5)P(3)] 3-kinase catalyses the phosphorylation of Ins(1,4,5)P(3) to Ins(1,3,4,5)P(4). cDNAs encoding two isoenzymes of Ins(1,4,5)P(3) 3-kinase (3-kinases A and B) have been described previously. In the present study, we report the cloning of a full-length 2052 bp cDNA encoding a third human isoenzyme of the Ins(1,4,5)P(3) 3-kinase family, referred to as isoform C. This novel enzyme has a calculated molecular mass of 75. 207 kDa and a K(m) for Ins(1,4,5)P(3) of 6 microM. Northern-blot analysis showed the presence of a transcript of approx. 3.9 kb in various human tissues. Inositol trisphosphate 3-kinase C demonstrates enzymic activity when expressed in DH5alphaF' bacteria or COS-7 cells. Calcium alone decreases the Ins(1,4,5)P(3) 3-kinase activity of the 3-kinase C isoenzyme in transfected COS-7 cells. This inhibitory effect is reversed in the presence of calmodulin. The recombinant bacterial 3-kinase C can be adsorbed on calmodulin-Sepharose in the presence of calcium. The present data show that Ins(1,4,5)P(3) 3-kinase C: (i) shares a conserved catalytic domain of about 275 amino acids with the two other mammalian isoforms, (ii) could be purified on a calmodulin-Sepharose column and (iii) could be distinguished from the A and B isoenzymes by the effects of calcium and of calmodulin.

The influence of the peripheral reflection wave on left ventricular hypertrophy in patients with essential hypertension.

The objective of this study was to clarify the relationship between afterload, which consists mainly of the vascular reflection wave, and left ventricular hypertrophy in patients with untreated essential hypertension using the fingertip photoplethysmogram (PTG) and second derivative wave (SDPTG) methods, the simplest and most convenient tools for pulse wave analysis. The augmentation index (AI) is defined as the ratio of the height of the late systolic peak, augmented by the peripheral reflection wave, to that of the early systolic peak caused mainly by left ventricular ejection in the pulse. Increased AI of the PTG and negative d/a, obtained by multiplying the ratio of the late re-decreasing wave (d wave) to the initial positive wave (a wave) of the SDPTG by -1, have the same meaning as increased ascending aortic AI. The left brachial artery blood pressure was measured in 60 patients. The PTG and SDPTG of the right second finger were recorded by a digital photoplethysmograph. The left ventricular mass index (LVMI) was investigated by ultrasonography. Subjects were assigned to one of two groups: a low AI (AI of PTG<1.6; group 1) or a high AI (AI of PTG> or =1.6; group 2) group. LVMI was significantly higher in group 2 than in group 1. In the study group as a whole, the LVMI was positively correlated with both the AI of PTG (r=0.60, p<0.0001) and negative d/a (r=0.63, p<0.0001). An increase in the LVMI was seen in subjects with an augmented late systolic component in the waveform. It was concluded that an increase in the peripheral reflection wave on the left ventricle is one of the important factors causing cardiac hypertrophy in patients with hypertension.

Is diabetes mellitus a major risk factor in coronary artery bypass grafting? The influence of internal thoracic artery grafting on late survival in diabetic patients.

OBJECTIVE: The presence of diabetes could possibly have an adverse influence on the late results of coronary artery bypass grafting (CABG). A retrospective observational risk-unadjusted estimation study was conducted to clarify the magnitude of this unfavorable influence of diabetes based on our experience at Juntendo University. METHODS: Between January 1984 and December 1995, 1,618 primary CABG operations were performed and 99.0% of these patients were followed up for a mean period of 81.2 months with a maximal follow-up of 14 years. Among the 1,610 patients who were successfully followed up, 523 patients (32.5%) were diabetic and this cohort was compared with 1,087 nondiabetic patients regarding the patient profiles, perioperative outcome, and the long-term outcome. RESULTS: Diabetic patients included a higher proportion of females, a greater preoperative presence of renal insufficiency, a higher rate of three vessel disease, and reception of a greater number of grafts (mean: 2.5 versus 2.4) and an internal thoracic artery graft (68% versus 58%). Hospital mortality was not significantly different (2.1% vs 1.0%: ns). An actuarial analysis revealed a significantly unfavorable long-term survival in the diabetic group (59.6%) at 14 years, compared with the nondiabetic group (73.4%), however diabetic patients with an internal thoracic artery graft had a favorable long-term survival (82.0%) at 13 years, and this finding was almost identical to that of nondiabetic patients with an internal thoracic artery graft (88.5%). CONCLUSION: We conclude that the presence of diabetes appears to be a major risk factor in patients undergoing CABG. However, diabetic patients with an internal thoracic artery graft had a survival almost identical to that of nondiabetic patients with an internal thoracic artery graft.

[Impending paradoxical embolism visualized by echocardiography combined with pulmonary embolism: a case report].

A 43-year-old man was admitted to our hospital complaining of dyspnea on exertion and dizziness. Transthoracic echocardiography revealed a mobile mass (3.5 x 1.0 cm) attached to the left atrial septum and transesophageal echocardiography showed the mass in the right atrium protruding through the patent foramen ovale into the left atrium. A mobile snake-like thrombus was apparent in the right atrium and right ventricle. The diagnosis was pulmonary embolism with impending paradoxical emboli.

Regional difference of neuronal vulnerability in the murine hippocampus after transient forebrain ischemia.

We have investigated the regional difference of neuronal vulnerability within the hippocampus in the C57BL/6 strain mice after forebrain ischemia. Both common carotid arteries of fifty mice were occluded for 12 min and the mouse brain was examined with cresyl violet staining. The CA4 sector was found to be the most vulnerable within the hippocampus. The CA2 and the medial CA1 sector was the 2nd and 3rd most vulnerable regions. However, The lateral part of the CA1 sector, CA3 sector and the dentate gyrus were resistant to ischemic insult.

Assessment of vascular aging and atherosclerosis in hypertensive subjects: second derivative of photoplethysmogram versus pulse wave velocity.

The pulse wave velocity (PWV) and the photoplethysmogram (PTG) are noninvasive methods for evaluating the pulse wave. The PWV has been associated with age and arterial hypertension, and an index of the second derivative of PTG (SDPTG) is correlated with age and other risk factors for atherosclerosis. The aim of this study was to compare SDPTG and PWV concerning the influencing factors of vascular compliance, including age and atherosclerosis, in a large hypertensive population. We studied consecutively 524 essential hypertensives, 140 with atherosclerotic alterations (AA), defined on the basis of clinical events including coronary heart disease, peripheral vascular disease, stroke, and abdominal aorta aneurysm. The PWV carotid-femoral was measured by a Complior device and the SDPTG was recorded by Fukuda FCP-3166. The augmentation index (AUI) of PTG was defined as the ratio of the late systolic peak to that of the early systolic peak in the pulse. The SDPTG consists of an a,b,c, and d wave in systole and an e wave in diastole; an SDPTG aging index (AI) was calculated as (b-c-d-e)/a. The patients with AA presented a higher PWV (14.9 +/- 4 m/sec v 12.4 +/- 2 m/sec, P < .001), PTG AUI (0.322 +/- 0.16 v 0.252 +/-0.09, P < .001), and SDPTG AI (-0.093 +/- 0.03 v -0.271 +/- 0.018, P < .001). However, in patients 60 years of age, only PWV remained higher in those with AA, whereas in patients >60 yr, both PWV and SDPTG AI remained higher in those with AA. The PWV was independently influenced by age, systolic blood pressure, glucose, AA, and plasma creatinine, whereas the PTG AUI was influenced by age and systolic pressure and the SDPTG AI by age and AA. In a logistic regression model for the presence of AA, including age, plasma creatinine, smoking, and diastolic BP, PWV was a significant independent determinant of AA, whereas SDPTG-AI weakly entered into the model. This study provides evidence that the aortic PWV reflects better than the SDPTG the modifications of the arterial compliance related to age, blood pressure, and atherosclerosis. However, the SDPTG AI may be useful for evaluation of vascular aging in hypertensives.

Second derivative of photoplethysmogram in children and young people.

The characteristics of the second derivative of the photoplethysmogram (SDPTG) were clarified in children and young people, and the factors affecting the SDPTG wave pattern were examined. The study group comprised 775 healthy subjects aged 3-20 years (mean, 10+/-5). The blood pressure of the left brachial artery was determined in the resting sitting position and then the fingertip PTG and the SDPTG were automatically measured using a digital photoplethysmograph, with the sensor located at the cuticle of the second digit of the right hand. The values used were the b/a, c/a, d/a, and e/a ratios, and the SDPTG aging index (SDPTG-AI). With increasing age, the systolic blood pressure and height increased (r = 0.52, 0.92). Aging decreased the b/a ratio and SDPTG-AI (r = -0.58, -0.67) and increased the c/a and e/a ratios (r = 0.42 and 0.42). There was no significant correlation between blood pressure and indices of SDPTG. As height increased, the b/a ratio and SDPTG-AI decreased (r = -0.57, -0.71), whereas the c/a and e/a ratios increased (r = 0.42 and 0.46). In males the SDPTG-AI decreased with age from 3 to 18 years and then increased, and in females it decreased with age from 3 to 15 years and then increased. Overall, the SDPTG-AI decreased with age between 3 and 18 years and then increased, forming a J curve. In the children's and young people's SDPTG, the b/a and SDPTG-AI decreased and the c/a and e/a ratios increased with age. The length of the vascular system and the inner diameter and wall thickness of vessels may modify the SDPTG wave pattern in the growth period. Thereafter, as the effects of these factors decrease, the increase in intravascular pressure and decreasing wall elasticity due to aging may affect the wave pattern.

Coronary artery bypass grafting. Late result of actual 10-years follow-up in 376 patients.

OBJECTIVES: The aim of this study was to analyze the long-term results of coronary artery bypass grafting in Japanese patients who were followed more than 10 years after surgery, and, without resorting to actuarial methods, to determine the factors that influence long-term survival. SUBJECTS AND METHODS: From January 1984 through December 1986, 376 patients received coronary artery bypass grafting at the Department of Cardiothoracic Surgery of Juntendo University; it is these patients who comprise the subject of this study. Of the 376 patients, 328 were males (87.2%) and the mean patient age was 58.5 years (range: 32 to 78 years). Single vessel disease was present in 36 patients (10.8%), double vessel disease in 89 patients (26.7%), triple vessel disease in 150 patients (45.0%) and 58 patients (17.4%) with 50% of more stenosis of the left main coronary artery. The mean number of grafts used was 2.3 grafts per patient, while internal thoracic artery conduits were used in 66 patients (17.6%). RESULTS: The 10-year survival rate for the entire series of patients was 81.4%. Patients receiving internal thoracic artery grafts had a 10-year survival rate of 94.0%, superior to the 78.0% rate found in patients who received only saphenous vein grafts. Other risk factors associated with reduced survival rates, besides non-use of internal thoracic artery, were: advanced age, diabetes mellitus, hypertension, presence of left main coronary artery disease, and severely impaired left ventricular function. The 10-year cardiac event free rate in the total group was 80.4%. Of 70 patients who died during the follow-up period, 19 deaths were due to cardiac causes (27.1%), 19 due to malignant neoplasm (27.1%) and 13 due to the cerebral vascular accident (18.6%). CONCLUSIONS: Univariate analysis revealed that: the use of only saphenous vein grafts (P = 0.0055), advanced age (P < 0.0001), diabetes mellitus (P < 0.0001), hypertension (P = 0.0282), presence of left main coronary artery disease (P = 0.0140), and severely impaired left ventricular function (P = 0.0075) are associated with reduced survival in patients undergoing coronary artery bypass grafting in this cohort of patients.

[Adult case of isolated noncompaction of left ventricular myocardium revealed at hospitalization for tuberculous pleuritis].

A 48-year-old man was diagnosed with isolated noncompaction of the left ventricular myocardium. He had been suffering from dyspnea during light exercise since early February 1997, which worsened with time. Eventually, he visited our hospital on February 14. He was admitted urgently because orthopnea was observed and chest radiogram showed massive left pleural effusion. The diagnoses were pulmonary tuberculosis and tuberculous pleuritis. Echocardiography at admission showed generalized hypokinesis of the left ventricle, so we suspected that his condition was complicated by myocarditis. However, virus antibody levels were not elevated, and no obvious findings compatible with myocarditis or cardiomyopathy were obtained by right ventricular myocardial biopsy. Left ventricular contractility remained low and a trabecular mesh structure was seen at the left ventricular apex. Thus, the diagnosis was isolated noncompaction of the left ventricular myocardium. This disorder has been highlighted in pediatric patients, but few adult cases have been reported.

Effects of nicorandil on aortic input impedance: a comparative study with nitroglycerin.

A study of aortic input impedance was performed to evaluate the effects of nicorandil on the systemic circulation, and the effects were compared with those of nitroglycerin. Sixteen patients with coronary artery disease were divided into 2 age-matched groups. Aortic input impedance was obtained from Fourier analysis of aortic pressure and flow signals at baseline conditions, after intravenous administration of either 4 mg (Group 1) or 8 mg (Group 2) nicorandil, and 20 min after 0.3 mg sublingual nitroglycerin. In Group 1, the first harmonic impedance modulus (Z1, 304+/-140 dyne x s x cm(-5)) and the average of the first to third harmonics (Z1-3, 207+/-99 dyne x s x cm(-5)), indices of wave reflection, significantly decreased (24.4% (p<0.05) and 24.7% (p<0.01), respectively) after nicorandil, and 41.3% (p<0.01) and 33.9% (p<0.01) after nitroglycerin. The effects between the 2 vasodilators were not significantly different. In Group 2, Z1 and Z1-3 (275+/-138 and 196+/-93 dyne x s x cm(-5), respectively) also decreased after administration of nicorandil (28.4% (p<0.01) and 35.9% (p<0.01), respectively), and after administration of nitroglycerin (23.9% (p<0.01) and 28.7% (p<0.01), respectively), without any significant difference between the 2 drugs. Characteristic impedance and total peripheral resistance (R) in both groups remained unchanged except for R after 8 mg nicorandil (from 1830+/-415 to 1433+/-428 dyne x s x cm(-5); p<0.01). Like nitroglycerin, both doses of nicorandil reduced wave reflection. The reduction in R after 8 mg nicorandil is related to decreased tone in the resistance arteries, probably due to potassium channel opener effects.

The influence of changes in loading patterns on left ventricular relaxation in humans.

This clinical investigation was designed to determine the effect of changes in loading patterns on left ventricular (LV) relaxation when heart rate was maintained constant. Not only were changes noted in total load or time in which load is changed, but also the contour of the ascending aortic systolic pressure wave. Twenty patients were studied. LV and ascending aortic pressure were measured by a multisensor catheter under baseline conditions (C) and after an intravenous injection of 2.5 microg angiotensin (A) and sublingual administration of 0.3 mg nitroglycerin (N). A bipolar pacing catheter was placed in the right atrium to maintain a constant heart rate throughout the protocol. The augmentation index (AI), which characterizes the contour of the ascending aortic systolic pressure wave, was defined as the ratio of the height of the late systolic shoulder/peak to that of the early systolic shoulder/peak in the pulse. The rate of isovolumic LV pressure decline was calculated as a time constant (Tau). Ascending aortic systolic pressures (mmHg) were 127+/-29 (C), 158+/-20 (A) and 109+/-15 (N). AI were 1.61+/-1.14 (C), 2.08+/-1.11 (A) and 1.27+/-1.14 (N). Tau values (msec) were 49+/-4 (C), 54+/-4 (A) and 45+/-5 (N). Tau was prolonged proportionally with increasing AI (p<0.001, r=0.64). It was concluded that late systolic pressure augmentation in the ascending aorta is one important factor that influences the rate of isovolumic left ventricular pressure decline in humans.

Assessment of vasoactive agents and vascular aging by the second derivative of photoplethysmogram waveform.

To evaluate the clinical application of the second derivative of the fingertip photoplethysmogram waveform, we performed drug administration studies (study 1) and epidemiological studies (study 2). In study 1, ascending aortic pressure was recorded simultaneously with the fingertip photoplethysmogram and its second derivative in 39 patients with a mean+/-SD age of 54+/-11 years. The augmentation index was defined as the ratio of the height of the late systolic peak to that of the early systolic peak in the pulse. The second derivative consists of an a, b, c, and d wave in systole and an e wave in diastole. Ascending aortic pressure increased after injection of 2.5 microg angiotensin from 126/74 to 160/91 mm Hg and decreased after 0.3 mg sublingual nitroglycerin to 111/73 mm Hg. The d/a, the ratio of the height of the d wave to that of the a wave, decreased after angiotensin from -0.40+/-0.13 to -0.62+/-0.19 and increased after nitroglycerin to -0.25+/-0.12 (P<0.001 and P<0.001, respectively). The negative d/a increased with increases in plethysmographic and ascending aortic augmentation indices (r=0.79, P<0.001, and r=0.80, P<0.001, respectively). The negative d/a reflects the late systolic pressure augmentation in the ascending aorta and may be useful for noninvasive evaluation of the effects of vasoactive agents. In study 2, the second derivative of the plethysmogram waveform was measured in a total of 600 subjects (50 men and 50 women in each decade from the 3rd to the 8th) in our health assessment center. The b/a ratio increased with age, and c/a, d/a, and e/a ratios decreased with age. Thus, the second derivative aging index was defined as b-c-d-e/a. The second derivative wave aging index (y) increased with age (x) (r=0.80, P<0.001, y=0.023x-1.515). The second derivative aging index was higher in 126 subjects with any history of diabetes mellitus, hypertension, hypercholesterolemia, and ischemic heart disease than in age-matched subjects without such a history (-0.06+/-0.36 versus -0.22+/-0.41, P<0.01). Women had a higher aging index than men (P<0.01). The b-c-d-e/a ratio may be useful for evaluation of vascular aging and for screening of arteriosclerotic disease.

[Coronary reoperation].

From 1884 to 1997, 24 patients (1.3%) underwent coronary reoperation in a mean of 10.18 +/- 3.35 ears after the first operation at Juntendo University. The mean age of the patients at reoperation was 60.7 +/- 8.0 years. Although 2 patients had received a left internal thoracic artery graft at the primary operation, both grafts were already occluded. At reoperation, 19 patients received at least one internal thoracic artery, and 2 received a gastroepiploic artery graft. The mean number of grafts was 1.96 +/- 0.67 at reoperation. One patient underwent reoperation combined with pseudoaneurysmectomy at the proximal anastomosis site, and one patient reoperation combined with mitral valve replacement. There were 2 in-hospital deaths. The use of an arterial graft to the LAD is recommended at reoperation because of its long-term superiority. Since transmyocardial laser revascularization (TMLR) and minimally invasive direct coronary artery bypass (MIDCAB) at reoperation have recently been reported, these strategies may be considered as useful methods in future.

[Influence of wall thickness on asynergy during exercise two-dimensional echocardiography in patients with old myocardial infarction].

The relationship between left ventricular wall motion worsening (new asynergy; newly developed or worsened asynergy) in the affected part of old myocardial infarction during exercise two-dimensional echocardiography and the wall thickness at diastole was evaluated in 20 patients with more than 51% diameter stenosis in only the infarcted related artery using symptom-limited graded supine bicycle exercise test and two-dimensional echocardiography. End-diastolic wall thickness at normal part of the wall (WtdN) and infarcted parts (WtdI) on the parasternal short-axis view at the papillary muscle level at rest were measured and the wall thickness ratio, WtdI/WtdN x 100(%), was calculated. The rate pressure product at the time when new asynergy appeared and the appearance time of new asynergy after starting exercise were measured in seconds. Mean values for the 20 patients were wall thickness ratio of 75.7 +/- 10.0% (mean +/- SD), new asynergy appearance time of 219 +/- 116 sec after exercise and rate pressure product of 14,209 +/- 2,997 mmHg. beat/min. Smaller wall thickness ratio was associated with lower rate pressure product levels (r = 0.696, p < 0.01) and shorter appearance time of new asynergy (r = 0.772, p < 0.01). There was no significant correlation between the percentage diameter stenosis of the infarct-related artery and appearance time of new asynergy or rate pressure product. New asynergy appeared at a specific infarcted part of the wall, and thinner walls were associated with shorter appearance time of new asynergy with lower rate pressure product levels, regardless of the severity of stenosis of the infarct-related artery.