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BACKGROUND Thrombolytic therapy is standard treatment in acute pulmonary thromboembolism (PTE) with hemodynamic instability. Although right heart thrombi (RHT) appear to increase mortality in acute PTE, large-scale studies of acute PTE with RHT are scarce.Methods and Results:Patient data (from August 2005 to May 2014) obtained from post-marketing surveillance of thrombolytic therapy using a tissue-type plasminogen activator were analyzed retrospectively. Of the 2,698 confirmed cases of acute PTE who underwent echocardiographic assessment, 166 (6.2%) were diagnosed with RHT. PTE patients with RHT, compared with those without RHT, had higher rates of mortality (20.2% vs. 10.4%, P

Background There is insufficient real-world data on the current status of Japanese patients with venous thromboembolism (VTE) or its treatment and prevention with rivaroxaban.Methods and Results:In this multicenter, prospective, observational study conducted in Japan, 1,039 patients with acute symptomatic/asymptomatic deep vein thrombosis (DVT) and pulmonary embolism (PE) with or without DVT prescribed rivaroxaban were enrolled at 152 institutions and observed for a median of 21.3 months. Mean age was 68.0±14.7 years, mean body weight was 60.3±14.1 kg, 59.0% were females, and 19.0% had active cancer. Incidences of recurrence or aggravation of symptomatic VTE (primary effectiveness outcome) and major bleeding (principal safety outcome) were 2.6% and 2.9% per patient-year, respectively. These outcomes did not differ between patients with DVT and those with PE (primary effectiveness outcome: 2.6% vs. 2.5% per patient-year, P=0.810; principal safety outcome: 3.5% vs. 2.4% per patient-year, P=0.394). The incidence of composite clinically relevant events, including recurrence or aggravation of symptomatic VTE, acute coronary syndrome, ischemic stroke, all-cause death, or major bleeding events, was 9.2% per patient-year. Multivariate analysis revealed that male sex, being underweight, having active cancer, chronic heart and lung disease, and previous stroke were independent determinants for composite clinically relevant events. Conclusions In Japanese clinical practice, a single-drug approach with rivaroxaban was demonstrated to be a valuable treatment for a broad range of VTE patients.

Missense mutations in the smooth muscle-specific isoform of the alpha-actin (ACTA2) gene, which encodes smooth muscle actin, congenitally cause systemic smooth muscle dysfunction, leading to multiple systemic smooth muscle dysfunction syndrome. This disease is often diagnosed through the development of congenital mydriasis, patent ductus arteriosus, or thoracic aortic aneurysm at a young age. Some patients develop cerebrovascular lesions, also known as ACTA2 cerebral arteriopathy, which cause ischemic stroke and require surgical revascularization. However, an effective and safe treatment has not yet been established owing to the rarity of the disease. Furthermore, most reports of this disease involve children, with only a few reports on adults and few detailed reports on treatment outcomes published to date. We report a 46-year-old woman with ACTA2 cerebral arteriopathy caused by Arg179His, the most common mutation in this disease; she is the oldest patient reported with this disease to the best of our knowledge. The patient was diagnosed with multiple systemic smooth muscle dysfunction syndrome and ACTA2 cerebral arteriopathy after experiencing a stroke in the right cingulate gyrus. She underwent direct triple bypass with three anastomoses of the right superficial temporal artery to the middle and anterior cerebral arteries. She developed an ischemic stroke as a postoperative complication.The efficacy and safety of this procedure have not been clearly confirmed owing to the frailty of the donor superficial temporal artery and the poor development of collateral circulation; however, direct bypass should be considered a treatment option for patients experiencing progressive multiple strokes.

The aim of this study is to validate the efficacy of drug-coated balloons (DCBs) for real-world de novo small vessel diseases including chronic total occlusion and bifurcation. DCB angioplasty has been reported to be effective in the treatment of de novo small vessel disease. However, the number of reports that have focused on complex lesions is limited. This observational study comprised consecutive patients who underwent DCB angioplasty for de novo small vessel disease with a reference diameter of less than 2.5 mm by visual estimation. Outcome parameters included late lumen loss, restenosis rate, and major adverse cardiac events, such as cardiac death, non-fatal myocardial infarction, and target lesion revascularization (TLR). Fifty-two patients underwent DCB angioplasty for 59 lesions with a reference vessel diameter of 1.93 ± 0.63 mm. Thirty-eight of the lesions (69%) were classified as type B2/C, including chronic total occlusions (20%) and bifurcations (33%). At the 8-month follow-up, late lumen loss was - 0.01 ± 0.44 mm with a restenosis rate of 20%. No cardiac deaths or myocardial infarctions were reported and only 5 (9%) angiographically driven TLRs were reported. DCB angioplasty offered an acceptable 8-month lumen patency and a stable clinical outcome for real-world complex de novo coronary diseases.

Deep vein thrombosis occasionally causes paradoxical embolism in patients with a patent foramen ovale (PFO). We report the case of a 42-year-old female who was hospitalized for stroke. Detailed investigations revealed the existence of a PFO, pulmonary embolism, and ovarian vein thrombosis extending to inferior vena cava. She had a uterine myoma to be operated on but no other thrombophilic disorders. Anticoagulation therapy with direct oral anticoagulant successfully reduced the thrombus and prevented the recurrence of paradoxical embolism. .

Background: In Japan, the safety and efficacy of thrombolytic therapy using tissue-type plasminogen activator for acute pulmonary embolism (PE) in the real world remain unclear. Methods and Results: A total of 1,254 patients with acute PE covered by the post-marketing surveillance of thrombolytic therapy using monteplase were divided into 3 groups: cardiopulmonary arrest (CPA)/collapse group (n=85); massive group, patients with unstable hemodynamics without CPA/collapse (n=217); and submassive group, patients with stable hemodynamics and right ventricular dysfunction (RVD) (n=465). In the efficacy analysis of 767 cases, the response rate to monteplase was 94.6% according to pulmonary circulation assessment and 93.3% according to clinical efficacy judged by symptoms and signs. Overall survival rates at 30 days after monteplase administration were 89.2% overall, 41.2% for the CPA/collapse group, 93.0% for the massive group, and 96.3% for the submassive group. When the safety of monteplase was analyzed in 1,241 cases, severe bleeding complications occurred in 100 patients (8.1%). Intracranial hemorrhage (ICH) occurred in 21 patients (1.7%), but no significant independent predictors were found in multivariate analysis. Conclusions: Thrombolytic therapy is highly effective in Japanese acute PE patients and offers acceptable safety, but attention is needed regarding severe bleeding complications, including ICH. (Circ J 2012; 76: 2471–2480)

Background: Few studies have compared the ability of cardiac magnetic resonance (CMR) with that of scintigraphy using 201-thallium (201-Tl) and 99m-technetium pyrophosphate (99m-Tc PYP) to evaluate microvascular obstructions (MOs). In the present study the relationship between the scintigraphic and CMR characteristics of MOs after acute myocardial infarction (MI) was examined. Methods and Results: The 14 patients (age 69±8 years, 11 males) underwent 201-Tl/99m-Tc PYP SPECT 7±3 days, initial CMR 16±12 days, and follow-up CMR 193±20 days after a reperfused first acute MI. Each image was analyzed using a 17-segment model. Segmental extent of delayed enhancement (DE), wall motion (WM) and degree of 201-Tl uptake were scored in 238 segments. Of 91 MI segments, MO was recognized in 22 (25%) segments on CMR. WM was significantly better in proportion to 201-Tl uptake (P=0.01) in MO segments. All 8 MO segments with WM improvement at follow-up had 99m-Tc PYP uptake, although only 3 (21%) of 14 MO segments that did not show WM improvement at follow-up had 99m-Tc PYP uptake (P=0.001). Conclusions: 99m-Tc PYP and 201-Tl scintigraphy have the potential to predict WM status and improvement of the MO region after reperfused acute MI. (Circ J 2010; 74: 2633-2640)

The outcome of cardiac sarcoidosis is sometimes very poor. Ventricular tachycardia (VT) associated with cardiac sarcoidosis is the most common cause of sudden death among most patients. However, there is no established method for potential VT in patients with cardiac sarcoidosis. Thus, we investigated the utility of evaluation of gallium-67 scintigraphy for potential VT in patients with cardiac sarcoidosis. Cardiac sarcoidosis was diagnosed in 25 patients at ours or collaborating hospitals during the period 1982 through 2004. Twenty-one of these patients were treated with corticosteroid, and these patients were divided into two groups, depending on whether VT was present: a non-VT group (n=7) and a VT group (n=14). Laboratory and gallium-67 scintigraphy findings were examined in both groups. During the follow-up period, initial and maintenance dosages of corticosteroid did not differ significantly between the groups. Accumulation of gallium-67 in the heart at the time of diagnosis was detected more frequently in the VT group than in the non-VT group (14.3 vs. 71.4%, p

Introduction: Radiofrequency catheter ablation (RFCA) of severely symptomatic monomorphic ventricular premature beats (VPBs) is reported to be a safe and effective treatment option. However, the chronic hemodynamic effects of these VPBs have not been precisely evaluated. Methods and Results: We sought to investigate chronic effects after decreasing the number of VPBs by RFCA. A total of 47 patients who had no underlying heart disease and frequent monomorphic VPBs, consisting of more than 10,000 beats per day (24,194 ± 12,516 beats per day), were enrolled. Patients were treated with RFCA and followed up over 6 months as outpatients. Echocardiography and serum B-type natriuretic peptide (BNP) level were repeatedly checked before and after RFCA. In 38 patients, whose VPBs were dramatically decreased to less than 1,000 beats per day by successful RFCA, left ventricular (LV) end-diastolic dimension (LVEDd) and end-systolic dimension (LVESd) measured by echocardiography decreased significantly (LVEDd: 50 ± 5 to 48 ± 5 mm, P < 0.01; LVESd: 33 ± 7 to 30 ± 6 mm, P < 0.01) in association with improvement of BNP level (39.9 ± 34.1 to 16.8 ± 10.3 pg/mL, P = 0.0001). In nine patients, whose VPBs were treated unsuccessfully by RFCA or that recurred, LV dimensions and BNP level did not change during the follow-up period. Conclusion: Significant improvement in LV dimensions and serum BNP level appeared to indicate that RFCA of VPBs ameliorated occult cardiac dysfunction induced by frequent VPBs.

A 48-year-old Japanese man was admitted to hospital for acute myocardial infarction associated with a giant organized thrombus occupying the left sinus of Valsalva. Cardiac catheterization revealed no organic stenosis in either coronary artery, but left ventriculography and aortography showed a filling defect above the left coronary cusp. Transesophageal echocardiography was immediately performed and showed a round mass filling the left sinus of Valsalva. A solid, round mass approximately 2.5 cm in diameter was removed during emergency surgery and determined to be a thrombus on the basis of microscopic findings. This is the second report of a giant organized thrombus occupying the entire left sinus of Valsalva, obstructing the ostium of the left coronary artery intermittently, and leading to acute myocardial infarction. (Circ J 2004; 68: 795 - 798)

Spontaneous degeneration of rapid atrial fibrillation (AF) to ventricular fibrillation has been documented in patients with hypertrophic cardiomyopathy (HCM) and Wolff-Parkinson-White (WPW) syndrome. However, the importance of rap

Despite excellent acute reperfusion results, 20%-30% of patients who undergo coronary stent implantation will develop angiographic restenosis and may require same additional treatments. Cutting Balloon angioplasty (CBA) causes less histological damage outside of the incised area than a regular balloon. However, regular plain old balloon angioplasty is sometimes required before CBA, as is adjunctive stenting and adjunctive angioplasty. These adjunctive strategies may negate the advantages of CBA. There is little data available on CBA as a standalone therapy for stent-related restenosis (SRS). The aim of this study was to evaluate the acute and 3- to 6-month angiographic recurrent restenosis rates following standalone CBA in a patient population treated for SRS and in whom optimal acute results were obtained. In this study, 40 patients with SRS (54 lesions) underwent standalone CBA with optimal acute results. For all lesions, coronary angiography was conducted before and after a standalone CBA procedure for SRS and systematically during 3-6 months to assess recurrent angiographic restenosis rates in the study population. In the study lesions, SRS was either diffuse disease (> 15 mm; 52%) or focal type (48%). Cutting Balloon diameter was 3.20 +/- 0.44 mm and maximal inflation pressure 8.7 +/- 1.2 atm. Ratio of Cutting Balloon diameter to restenotic stent diameter was 0.996 +/- 0.487. Multiple inflations (6 +/- 3 times) were performed. Number of used Cutting Balloon was 1.02 +/- 0.14. Complications were as follows; one non-Q-wave MI (1.9%); 0 death (0%), and 17 repeat target lesion revascularizations (TLRs; 32%). Follow-up coronary angiography (CAG) was not attained for one patient. The angiographic recurrent restenosis rate was 34%, with a higher rate observed when the SRS was diffuse type, 50% vs. 16% for focal-type SRS (P < 0.01). The recurrent restenosis rate for smaller vessels (vessel diameter < or = 3.0 mm) was the same as for larger ones. At follow-up CAG, diffuse-type recurrent restenosis (56%) presented nearly as frequently as that presenting in the original SRS lesions (52%). But four diffuse-type SRS (29%) changed into focal-type recurrent stenosis. In this study, standalone CBA for SRS with optimal acute results was associated with an angiographic restenosis rate of 34%. Diffuse-type disease had a higher recurrent restenosis rate. When CBA achieves acute optimal results, adjunctive stenting or adjunctive PTCA are not always necessary, particularly when the SRS is focal. As a result of CBA, some diffuse-type SRS may change into focal-type recurrent stenosis by the time of the next intervention.

A rare case of Williams syndrome diagnosed at the age of 41 is documented. The first subjective symptom was chest pain and the patient displayed many other features in addition to severe supravalvular aortic stenosis with a systolic gradient of 60 mmHg. The stenotic lesion had an area of 0.5 cm2, and was associated with dilated and tortuous coronary arteries. Extended aortoplasty was successfully performed and the postoperative course has been excellent without any cardiac symptoms. In spite of the severe cardiac lesions, this case had been largely asymptomatic and presented unusual features related to the diagnosis and management of this syndrome in an adult. The pattern of abnormalities found in this case suggested problems in relation to the calcitonin/calcitonin gene related peptide (CGRP) and the elastin gene occurring in embryonic organogenesis.

To evaluate the role of adrenal androgens in the development of arteriosclerosis, serum dehydroepiandrosterone sulfate (DHEAS), dehydroepiandrosterone (DHEA), aortic calcification and pulse wave velocity (PWV) were measured in 69 males and 119 females without overt cardiovascular disease. The steroids decreased with age in both sexes, and the reduction was significantly steeper in younger (or = 40 years) than in older (40 years) subjects only in females. When adjusted for age, the steroids were significantly lower in subjects with aortic calcification than in those without it, and the PWV was significantly slower in the latter. Adrenal androgens appear to retard the development and/or progression of arteriosclerosis.

Among 436 patients with hypertension unrelated to any renal lesion, renovascular damage, pheochromocytoma, Cushing’s syndrome or hyperthyroidism, 15 patients had low plasma renin activity (PRA) and el

To assess the regression of cardiac hypertrophy during long-term (12 years) antihypertensive treatment, the following parameters were determined in 93 patients with essential hypertension: SV1 + RV5 by electrocardiography (ECG), and septal wall (SW) and posterior wall (PW) thickness by echocardiography (UCG). The patients were treated with a thiazide diuretic alone (group 1), thiazide + beta-blocker (group 2), thiazide + methyldopa or nifedipine (group 3) or nifedipine or methyldopa alone (group 4). The blood pressure decreased gradually within 6 months of treatment. According to ECG, regression of left ventricular hypertrophy occurred during the initial 7 years in all groups, whereas in the subsequent 5 years, statistically significant regression was found only in the patients treated with thiazide + other drugs (group 3). By UCG, which was taken only at the 7th and 12th year, regression was detectable during the last 5 years in all groups. The apparent incidence of regression of hypertrophy was lower in the thiazide-alone group (group 1) than in the thiazide + beta-blocker group (group 2), most likely due to mild hypertension in group 1. A cardiovascular accident (nonfatal myocardial infarction) occurred only in 1 patient. We conclude that during long-term antihypertensive treatment, persistent, progressive reversal of cardiac hypertrophy takes place.

The aim of this study was to assess the effectiveness of an early predischarge exercise therapy, started 2 weeks following acute myocardial infarction (AMI), to working functional capacity. Seventeen AMI patients (10 males, 7 females, mean age 62 +/- 11 years) were examined in this study. Six, serious clinical symptoms and complications, were excluded, while the remaining 11 patients completed, the whole exercise therapy protocol (2 weeks). Patients performed exercise performed for 20-30 min twice daily at a target heart rate (90% level of heart rate at AT) on the basis of anaerobic threshold (AT) determined using treadmill ramp exercise with our protocol. Heart rates (HR) at rest, warming-up and AT point decreased significantly (p less than 0.05) after exercise therapy, although peak HR remained unchanged. O2 pulse at the AT point and endpoint, after exercise therapy, improved significantly (p less than 0.05), when compared to that before therapy. Moreover, AT and peak VO2 improved remarkably (p less than 0.05), as did exercise time to the AT point and endpoint after exercise therapy (p less than 0.05), when compared to that before therapy. These results indicate that the predischarge early exercise therapy begun 2 weeks after AMI will be effective and beneficial in improving working capacity with improvement of physical deconditioning. Additionally, it is necessary that patients with severe clinical symptoms and complications be excluded.

Study objectives Although percutaneous transluminal coronary angioplasty (PTCA) is known to have beneficial effects on exercise capacity, its effects on the cardiovascular response during the onset of exercise have not been clarified. The present study was undertaken to determine the effects of PTCA on the kinetics of oxygen uptake ( V ˙ o 2 ) during constant-work-rate exercise in patients with coronary artery disease, as well as on their indexes of maximal work capacity. Methods Seventeen patients with coronary artery disease who received successful PTCAs performed a 50-W constant-work-rate exercise test for 6 min and a symptom-limited incremental exercise test both before and 4 months after the PTCA procedure. V ˙ o 2 was calculated from breath-by-breath analysis of respired gases. The time constant of V ˙ o 2 kinetics during the onset of 50-W exercise was determined by fitting a single exponential function to the V ˙ o 2 response. Results In 14 patients without coronary restenosis, the time constant of V ˙ o 2 kinetics was significantly shortened from (mean ± SD) 57.4 ± 12.6 before PTCA to 48.2 ± 9.5 s after PTCA (p = 0.0035), indicating improved kinetics of the V ˙ o 2 response. In these subjects, the peak V ˙ o 2 obtained during maximal exercise testing also increased from 23.1 ± 3.5 to 26.5 ± 3.2 mL/min/kg, respectively (p = 0.0005). However, there was no improvement in these indexes in the patients who had restenosis after undergoing PTCA (n = 3). Conclusion Indexes of cardiopulmonary exercise testing, which reflect an efficiency of oxygen flow to the exercising muscle, can be used as an objective, noninvasive, and cost-effective guide for understanding which patients will not have coronary restenosis following PTCA.

Background Symptom-limited incremental exercise tests are used to estimate the severity of cardiovascular disease and the patient’s daily activity. However, there is a need for objective parameters for submaximal exercise. To test the hypothesis that a decrease in maximal exercise capacity can be estimated by oxygen uptake (V̇ o 2 ) kinetics, we measured the time constant of V̇ o 2 both during the onset of constant work rate exercise at 50 W and during recovery from this exercise and compared it with data obtained during maximal exercise in patients with cardiovascular disease and in normal subjects. Methods and Results A total of 34 patients with cardiovascular disease and 14 normal subjects performed 6 minutes of 50-W constant work rate exercise and an incremental exercise test to the symptom-limited maximum on a cycle ergometer. V̇ o 2 was calculated from respiratory gas analysis on a breath-by-breath basis. The time constant of V̇ o 2 during the onset of 50-W exercise was 61.4±15.2 seconds in patients with cardiovascular disease, significantly longer (the kinetics of V̇ o 2 were slower) than that in normal subjects (48.8±10.4 seconds, P =.008). The time constant of V̇ o 2 during the onset of exercise was significantly negatively correlated with peak V̇ o 2 ( r =−.67) and maximal work rate ( r =−.66). The time constant during recovery, which did not differ significantly from that of exercise, was also prolonged in patients with cardiovascular disease; it showed a negative correlation with peak V̇ o 2 ( r =−.63) and maximum work rate ( r =−.54). Conclusions The time constant of V̇ o 2 during and after recovery from 50 W of constant work rate exercise, which does not require the subject’s maximal effort, is a useful and objective measure of exercise capacity in patients with mild to moderate cardiovascular disease.

Method We analyzed 20 consecutive patients (14 male; age 64 ± 12 years) with first acute inferior MI due to proximal right coronary lesion. All patients were assessed with cardiac MRI after primary percutaneous coronary intervention and followed up for a median (25, 75 percentiles) of 6 (5, 6) months. We assessed the association of RV function with length of cardiac care unit (CCU) treatment as an index of short-term prognosis by using multiple regression analysis, and used Kaplan-Meier analysis to demonstrate the association of RV dysfunction with occurrence of heart failure (HF) after discharge as an index of long-term prognosis. Results RV involvement was diagnosed with delayed enhancement MRI in 11 patients (55%). Patients with RV involvement had lower RV ejection fraction (EF) (32.4 ± 8.6 % vs 43.2 ± 7.7 %; p = 0.009) and longer duration of CCU treatment (5.3 ± 2.3 days vs 3.5 ± 1.9 days; p = 0.038) than those without RV involvement, although there were no significant differences regarding clinical, angiographic and the other MRI characteristics such as left ventricular parameters. By multiple regression analysis, RVEF was an independent predictor of length of CCU treatment (standardized partial regression coefficient -0.799, partial regression coefficient -0.127; 95% confidence interval -0.222 to -0.031; p = 0.017). KaplanMeier analysis demonstrated that RVEF

Background: Right ventricular septal (RVS) pacing is an alternative to right ventricular apical (RVA) pacing, but long term lead safety and stability of RVS sometimes differ in each hospital. Methods and Results: A total of 32 patients undergoing single or dual-chamber pacemaker implantation were included in this study. The right ventricular lead was implanted on the septum in 12 patients and in the apex in 20. Ventricular amplitude, pacing threshold and lead impedance were measured twice a year after the implantation in both group, and were compared respectively. There were no major perioperative complications in both group. There was no significant difference of ventricular amplitude and lead impedance in both group, but pacing threshold of RVS group was significantly higher at six months after the implantation than at the postoperative period. Pacing threshold showed no significant difference between RVS group and RVA group at the postoperative period, but at six and 12 months after the implantation, that of RVS group was significantly higher than RVA group. Conclusion: RVS pacing is a safety available method compared with RVA pacing. Pacing threshold of RVS group tends to increase after the implantation, but stabilizes within a year.

To determine whether left ventricular (LV) filling abnormalities in diabetes are associated with diabetic microangiopathy, and to evaluate the effect of a short-term glycemic control on the filling abnormalities, diastolic filling dynamics were assessed by pulsed Doppler echocardiography in 246 patients with non-insulin-dependent diabetics. Isovolumic relaxation time and the ratio of peak flow velocity of atrial filling wave to peak flow velocity of early filling wave (A/E) were significantly greater in diabetic patients than in age- and sex-matched control subjects. Diabetic patients with retinopathy had significantly greater isovolumic relaxation time and A/E values than those without retinopathy. A/E was significantly decreased 1 month after insulin treatment in those without, but not with retinopathy. It is concluded that LV diastolic filling is impaired in mildly hyperglycemic patients with non-insulin-dependent diabetes mellitus without severe complications, the abnormality being more intense in patients with retinopathy. A short-term glycemic control results in a marked decrease in abnormalities in patients without, but not with retinopathy.

Patients with diabetes were compared with nondiabetic control subjects, with respect to the prevalence of silent myocardial ischemia, by means of treadmill exercise testing and coronary angiography. Results of treadmill exercise testing showed ischemic ST depression in 41 of the 132 diabetic patients (mean age 61 +/- 4 years) and in 42 of the 140 nondiabetic control subjects (mean age 60 +/- 8 years) (31% vs 30%, p = NS). Coronary angiography was performed in 36 of 41 diabetic patients and 34 of 42 nondiabetic control subjects with positive results of treadmill exercise tests, who gave their consent. Among "treadmill-positive" subjects, diabetic patients had a prevalence of silent myocardial ischemia that was 2.2 times higher than that in nondiabetic control subjects (p less than 0.05). Diabetic patients who received insulin had a 2.6 times higher prevalence of silent myocardial ischemia than those who did not (p less than 0.05). Similarly diabetic patients with retinopathy has a 2.5 times higher prevalence of silent myocardial ischemia than those without it (p less than 0.05).

In order to study the relationship between the left atrial size and atrial fibrillation (AF) in patients with thyrotoxicosis, 92 patients with Graves' disease were examined. Out of 92 patients (23 men and 69 women, age 7-71 years), 21% had AF: 31% of the patients older than 40 years had AF whereas none of the patients younger than 40 years had AF. Echocardiography revealed that the left atrial enlargement (more than 40 mm) exist in 7% of patients younger than 40 years, in 2% of those older than 40 years without AF and 94% of those older than 40 years with AF. Serum T3 and T4 were higher in the patients with AF than in those without AF when patients older than 40 years were analyzed.

Cardiac manifestations in 321 patients on chronic hemodialysis (dialysis duration of from 0.1 to 11.3 years) were examined with non-invasive technique. In contrast to the previous assumption that cardiac dilatation and pericardial effusion are common in patients on chronic hemodialysis, interventricular septal hypertrophy (51.3%) and left ventricular posterior wall hypertrophy (47.1%) on echocardiography and left ventricular hypertrophy (47.0%) on ECG were the most frequent abnormalities in these patients. Although premature beats on routine ECG were found in a limited number of patients (4.7%), ventricular premature beats were recognized in 45.7% and high grade arrhythmias in 27.2% of 92 patients examined with 24-hour Holter ECG monitoring. There were no high grade arrhythmias and the frequency of ventricular premature beats was 19.4% in 31 age-matched healthy subjects studied. Furthermore, the PQ interval was progressively prolonged in relation to the duration of hemodialysis. This finding may suggest that long-term hemodialysis is associated with disturbances of the conduction system. These results indicate that myocardial hypertrophy and high grade arrhythmias are the prominent findings in uremic patients maintained on hemodialysis. We consider that such high grade arrhythmias could be responsible for a high incidence of cardiac death in these patients.

To investigate the hemodynamic aspects across a stenosis in the cardiovascular system, in vitro, in vivo, and clinical studies were performed. The results are summarized as follows: 1) Remarkable changes in the pressure profile were recognized downstream. The relationship between pressure gradient and flow across the stenotic orifice revealed an inverse linear relationship in in vitro studies, but showed a slight convex curve in in vivo studies. 2) The critical stenosis in vitro and in vivo studies 10% and 25%, respectively. 3) In the group of mitral valve area larger than 0.5 cm2, flow coefficient C was smaller than 1.0 and blood flow could be "vena contracta". 4) Gorlin's formula is considered to be appropriate in the cases with valve area larger than 0.5 cm2. But Gorlin's formula may over-estimate in the group with valve area smaller than 0.5 cm2.