Saki Ito

Impairment of platelet retention rate in patients with severe aortic valve stenosis.

BACKGROUND Recent reports revealed the presence of acquired von Willebrand syndrome type 2A in patients with aortic valve stenosis (AS). von Willebrand factor (vWF) has been shown to play a vital role in platelet adhesion. Therefore, we measured the platelet retention rates, which reflect platelet adhesion, in patients with severe AS. METHODS In addition to echocardiography, routine blood screening tests were performed and the platelet retention rates were measured using collagen-coated bead columns in 21 patients with severe AS and in 21 control subjects. RESULTS Patients with severe AS showed the maximum aortic valve pressure gradients of 110.9±22.7 mmHg, and effective orifice areas of 0.59±0.20 cm2. The results of routine blood tests in patients with severe AS were comparable to those of control subjects; however, the platelet retention rates in the AS patients (7.3±5.0%) were significantly lower than those in control subjects (30.5±11.8%, p<0.001). A significant negative correlation was observed between maximum aortic valve pressure gradients and platelet retention rates (r = -0.81, p<0.001). In 8 patients with severe AS, the platelet retention rates increased from 5.8±3.6% to 16.0±2.4% after aortic valve replacement (p<0.001). CONCLUSION These findings suggest that impairment of platelet retention rate is seen in almost all patients with severe AS. Clinicians should be aware of the possibilities of vWF-mediated platelet dysfunction and bleeding tendency in patients with severe AS.

Left Atrial Remodeling and Recurrence of Congestive Heart Failure in Patients Initially Diagnosed with Heart Failure

Left atrial volumes (LAVs) have been suggested to represent long‐term exposure to elevated pressures. This study examined the recurrence of heart failure (HF) based on LAV in patients initially diagnosed with congestive HF (CHF).

A case of long QT syndrome having compound mutations of KCNH2 and SCN5A

Long QT syndrome (LQTS) is a hereditary ion channelopathy resulting in prolonged cardiac repolarization and abnormal prolongation of the QT interval on the electrocardiogram (ECG). The patients are likely to develop ventricular arrhythmias and sudden cardiac death. Molecular biology and basic electrophysiology studies revealed an approach to the management of patients with LQTS, which includes genotype-based risk stratification. A 16-year-old-woman with QT prolongation on ECG had frequent syncopal episodes and an attack of ventricular tachycardia followed by ventricular fibrillation. The SCN5A mutation (intravene sequence 4-1 c/t) in addition to the KCNH2 mutation (Arg56Gln) was identified. Her mother and older sister were also diagnosed as having LQTS, but had only a single mutation (KCNH2). Her older sister had an episode of syncope, but her mother did not. Genetic analysis sometimes reveals 2 or more mutations in LQTS patients with clinical phenotypes of the Romano-Ward syndrome. Compound mutations in different LQTS-related genes are likely to modify clinical characteristics. In addition, comprehensive screening of LQTS-related genes might be needed when facing family members with different clinical manifestations. <Learning objective: Molecular biology and basic electrophysiology studies revealed an approach to the management of patients with LQTS, which includes genotype-based risk stratification. We described a case of LQTS having compound mutations of KCNH2 and SCN5A who had frequent syncopal episodes and an attack of ventricular fibrillation. The mutations of 2 different genes were associated with a severe phenotype of LQTS. Comprehensive screening of LQTS-related genes might be needed for estimating the severity of LQTS.>.

Factors Influencing the Prognosis of Octogenarians with Aortic Stenosis in the Advanced Aging Societies

Objective The recognition of clinical symptoms is critical to developing an effective therapeutic strategy for aortic valve stenosis (AS). Although AS is common, little is known about the factors influencing the natural history of AS patients who are 80 years of age older in advanced aging societies. We investigated the natural history and indications for valve procedures in AS patients of 80 years of age or older. Methods The medical records of 108 consecutive AS patients (moderate grade or higher) who are 80 years of age or older (mean age, 84.2±3.9 years; female, 65 patients) were reviewed to investigate their symptoms, the development of congestive heart failure, the incidence of referral for aortic valve replacement and death. The median duration of follow-up was 9 months (interquartile range, 2 to 25 months). Results The probability of remaining free of events (valve replacement and death) was 29±13% in all patients. There was no significant difference in the aortic valve area of the symptomatic and asymptomatic patients (0.85±0.28 cm(2) vs. 0.88±0.25 cm(2), p=0.59). The aortic valve (AV) velocity and AV area index were predictors of subsequent cardiac events (p<0.05). Conclusion The severity of AS was the only factor to affect the prognosis of AS patients who were 80 years old of age or older. It is necessary to frequently monitor the subjective symptoms of such patients and to objectively measure the AV area.

A case of arrhythmogenic right ventricular cardiomyopathy in a 70-year-old patient

A 70-year-old man was admitted because of syncope and dyspnea. Two months before admission, exertional dyspnea occurred with syncope. Ventricular tachycardia with a monomorphic left bundle-branch block configuration was detected. An echocardiographic examination showed severe dilatation and diffuse, severe hypokinesis of the right ventricle, with thrombus formation in the right ventricular apex. Based on the clinical picture, the patient was diagnosed with arrhythmogenic right ventricular cardiomyopathy (ARVC). This case emphasizes the need for early identification of RV abnormalities in patients with ARVC to determine appropriate therapy.

Visually confirmed post-systolic shortening during the recovery period in four cases of Takotsubo cardiomyopathy

We report visually confirmed post-systolic shortening (PSS) during the recovery period and the relationship between PSS and electrocardiographic abnormalities in 4 cases of Takotsubo cardiomyopathy (TTC). In these 4 cases, the appearance of visually confirmed PSS during the recovery period coincided with observation of the deepest T wave and the longest QT interval. The transmural repolarization gradient and heterogeneous duration of myocardial contractions may cause PSS in the TTC recovery period.

SEVERITY OF AORTIC REGURGITATION ASSESSED BY AREA OF VENA CONTRACTA- A CLINICAL COLOR DOPPLER IMAGING STUDY

Quantitation of aortic regurgitation (AR) using echocardiography including the width of vena contracta (VC-W) is challenging. Three-dimensional (3D) echocardiography can directly measure the size of vena contracta area of AR jet regardless of rheological characteristics. We intended to assess the