Masaki Maruyama

Influencing factors on cardiac structure and function beyond glycemic control in patients with type 2 diabetes mellitus

BackgroundWe hypothesized that clinical factors other than glycemic control may influence abnormal cardiac function in patients with type 2 diabetes mellitus (T2DM). We aimed to investigate the independent factors for abnormal cardiac function among clinical factors in T2DM.MethodsWe studied 148 asymptomatic patients with T2DM without overt heart disease. Echocardiographic findings were compared between diabetic patients and 68 age-matched healthy subjects. Early (E) and late (A) diastolic mitral flow velocity and early diastolic mitral annular velocity (e’) were measured for assessing left ventricular (LV) diastolic function. We evaluated insulin resistance, non-esterified fatty acid, high-sensitive CRP, estimated glomerular filtration rate, waist/hip ratio, abdominal visceral adipose tissue (VAT), subcutaneous adipose tissue (SAT) and other clinical characteristics in addition to glycemic control. VAT and SAT were quantified by computed tomography.ResultsIn T2DM, E/A and e’ were significantly lower, and E/e’, left atrial volume and LV mass were significantly greater than in control subjects. In multivariate liner regression analysis, VAT was an independent determinant of left atrial volume (β =0.203, p=0.011), E/A (β =−0.208, p=0.002), e’ (β =−0.354, p<0.001) and E/e’ (β=0.220, p=0.003). Age was also an independent determinant, whereas fasting plasma glucose and hemoglobin A1c levels were not. In addition to systolic blood pressure, waist-hip ratio (β=0.173, p=0.024) and VAT/SAT ratio (β=0.162, p=0.049) were independent determinants of LV mass.ConclusionExcessive visceral fat accompanied by adipocyte dysfunction may play a greater role than glycemic control in the development of diastolic dysfunction and LV hypertrophy in T2DM.

Transbrachial intra-aortic balloon pumping for a patient with fulminant myocarditis

A 57-year-old man with acute myocarditis was transferred to our hospital from a local clinic. The patient experienced unexpected sudden cardiac arrest 16 h after admission. Mechanical cardiopulmonary support was started using percutaneous cardiopulmonary support, intra-aortic balloon pumping (IABP), continuous hemodialysis filtration, and temporary cardiac pacing with percutaneous cannulation of the femoral vessels. Hematoma developed at the IABP insertion site on the 5th day after admission. The IABP was removed, and another IABP system was inserted via the left brachial artery. The patient’s condition improved, and the IABP was removed on the 9th day after admission. The remainder of the patient’s in-hospital treatment was uneventful, and he showed near-normal left ventricular systolic function 1 year after discharge.

Significance of Coronary Artery Disease and Left Ventricular Afterload in Unoperated Asymptomatic Aortic Stenosis.

BACKGROUND Because the covariates of cardiovascular events in unoperated patients with asymptomatic aortic stenosis (AS) have not been adequately evaluated, we aimed to identify them. METHODSANDRESULTS A total of 230 patients with asymptomatic severe AS were retrospectively enrolled. The patients were divided into 2 groups based on aortic valve replacement (AVR) after enrollment: a non-AVR group (n=112), and an AVR group (n=118). The primary clinical endpoint was cardiovascular events, which were defined as cardiovascular death or hospitalization. Coronary artery disease [hazard ratio (HR): 3.62, 95% confidence interval (CI): 1.585-8.245, P<0.01] and high valvulo-arterial impedance (HR: 3.08, 95% CI: 1.261-7.532, P<0.05) were identified as independent covariates of cardiovascular events in the non-AVR group. The relative risk of cardiovascular events rose with an increase in the number of risk factors (P<0.0001). CONCLUSIONS In unoperated patients with asymptomatic AS, the presence of coronary artery disease and increased global left ventricular afterload may be associated with a poor prognosis.

The use of serum bepridil concentration as a safe rhythm control strategy in patients with atrial tachyarrhythmias

The aim of this study was to evaluate the clinical significance of serum bepridil (Bep) concentration (SBC) for safely managing patients with atrial tachyarrhythmias (AT).

When and how aortic stenosis is first diagnosed: A single-center observational study

BACKGROUND The development of clinical symptoms is associated with cardiovascular events in patients with aortic stenosis (AS). Thus, early diagnosis of AS is clinically important. However, there are few data on symptom status or the severity of AS when patients are first diagnosed, or on how AS is detected in routine practice. We aimed to investigate when and how AS patients are first diagnosed in our hospital. METHODS We retrospectively enrolled 198 AS patients diagnosed from 1989 to 2009, and identified their symptoms and AS severity at the time of the first diagnosis. We also assessed the reasons why they came to the hospital based on their medical records. RESULTS Of the 198 patients, 82 (41.6%) had voluntarily visited or been referred to our hospital after developing clinical symptoms (Symptomatic group). The remaining 116 patients (58.4%) had been asymptomatic, and cardiovascular disease was suspected during an annual or occasional health checkup (Asymptomatic group). The initial findings in the Asymptomatic group that led to the diagnosis of AS were: a systolic murmur on auscultation (62%), abnormal electrocardiography (27%), or abnormal echocardiography (11%). The Symptomatic group had significantly greater AS severity and an increased left ventricular mass index, and experienced more cardiac events (valve replacement or cardiac death) during the follow-up period. CONCLUSIONS About 40% of the AS patients in this study were not diagnosed until they developed clinical symptoms, suggesting that many other patients in the community might have a latent risk of cardiovascular events. Auscultation plays an important role in the early diagnosis of AS.

Cyst-like posterior aortic valve aneurysm associated with infectious endocarditis.

A 56-year-old male with a bicuspid aortic valve, in which the right and non-coronary leaflets were fused, developed high fever and acute decompensated heart failure. He was initially diagnosed with infectious endocarditis (IE) with significant aortic regurgitation at a local hospital by transthoracic echocardiography (TTE). His blood culture was positive for alpha-streptococci. After 2 weeks of intravenous antibiotic therapy, he was transferred to our institution for surgical treatment because he was unresponsive to antibiotics. Transesophageal echocardiography (TEE) revealed a cyst-like aneurysm of cavity formation at the left coronary cusp associated with turbulence flow around the cavity and aortic root (Fig. 1). The patient underwent aortic valve replacement and the aortic root abscess was reinforced with an autologous pericardial patch. There was vegetation on the left leaflet as well as an annular abscess, which was consistent with the echocardiographic findings (Fig. 2). It has been reported that patients with a bicuspid aortic valve associated with IE incur a high risk of abscess formation compared to those with a tricuspid aortic valve, and almost three-quarters of these patients require early surgery [1, 2]. The histologic abnormality that underlies aortic root complications in bicuspid-valve IE is cystic medial necrosis, which is characterized by a non-inflammatory loss of smooth muscle cells and fragmentation of elastic fibers [3]. A perivalvular abscess is reported to be associated with an increased risk of death and devastating complications, including systemic embolization, conduction system abnormality and cardiac tamponade [4, 5]. Therefore, prompt surgical intervention should be considered to prevent further extension of infection and tissue