Changes in Exercise Tolerance over Time in Patients with Transthyretin Amyloidosis Cardiomyopathy Treated with Tafamidis.

Tafamidis improves the prognosis of patients with transthyretin amyloidosis cardiomyopathy (ATTR-CM). Additionally, it delays the decline in exercise tolerance, as observed in the six-minute walking test. However, the changes in cardiopulmonary function over time based on cardiopulmonary exercise tests are unclear. Thus, this preliminary study investigated the changes in exercise tolerance after one year of tafamidis treatment using cardiopulmonary exercise testing. Eight patients with ATTR-CM (average age: 77 years; male: n = 7) underwent cardiopulmonary exercise testing at baseline and after one year of tafamidis treatment. All eight patients completed a one-year follow-up. At baseline, the anaerobic threshold oxygen uptake (AT VO2: 10.9 ± 1.5) and peak VO2 (14.3 ± 3.0 mL/kg/minute) indicated relatively favorable exercise capacity; however, the minute ventilation/carbon dioxide production (VE/VCO2 slope), which indicates effective ventilation, showed poor performance (33.7 ± 12.8). One year after tafamidis treatment, frailty, as assessed by the Clinical Frailty Scale, had progressed in seven of eight patients (88%) (P < 0.01), and AT VO2 and peak VO2 were significantly reduced (19.2% and 22.3%, respectively; P < 0.05). The VE/VCO2 slope and peak O2 pulse decreased nonsignificantly by approximately 20% (P = 0.47, and P = 0.16, respectively). Further, the structure of the ventricles and atrium and the left ventricle ejection fraction on echocardiography did not change. Thus, exercise tolerance in patients with ATTR-CM was reduced after one year despite tafamidis administration. Not only ATTR-CM progression, but also frailty progression may influence this decrease in exercise tolerance. A comprehensive approach, including tafamidis administration and cardiac rehabilitation, is required for further improvement in the exercise capacity of patients with ATTR-CM.

Cardiac amyloidosis screening using a relative apical sparing pattern in patients with left ventricular hypertrophy.

BACKGROUND: Cardiac amyloidosis (CA) mimics left ventricular hypertrophy (LVH). It is treatable, but its prognosis is poor. A simple screening tool for CA would be valuable. CA is more precisely diagnosed with echocardiographic deformation parameters (e.g., relative apical sparing pattern [RASP]) than with conventional parameters. We aimed to 1) investigate incremental benefits of echocardiographic deformation parameters over established parameters for CA screening; 2) determine the resultant risk score for CA screening; and 3) externally validate the score in LVH patients. METHODS: We retrospectively studied 295 consecutive non-ischemic LVH patients who underwent detailed diagnostic tests. CA was diagnosed with biopsy or 99mTc-PYP scintigraphy. The base model comprised age (≥65 years [men], ≥70 years [women]), low voltage on the electrocardiogram, and posterior wall thickness ≥ 14 mm in reference to the literature. The incremental benefit of each binarized echocardiographic parameter over the base model was assessed using receiver operating characteristic curve analysis and comparisons of the area under the curve (AUC). RESULTS: Fifty-four (18%) patients had CA. RASP showed the most incremental benefit for CA screening over the base model. After conducting multiple logistic regression analysis for CA screening using four variables (RASP and base model components), a score was determined (range, 0-4 points). The score demonstrated adequate discrimination ability for CA (AUC = 0.86). This result was confirmed in another validation cohort (178 patients, AUC = 0.88). CONCLUSIONS: We developed a score incorporating RASP for CA screening. This score is potentially useful in the risk stratification and management of LVH patients.

Genetic determinants and an epistasis of LILRA3 and HLA-B*52 in Takayasu arteritis.

Takayasu arteritis (TAK) is a systemic vasculitis with severe complications that affects the aorta and its large branches. HLA-B*52 is an established susceptibility locus to TAK. To date, there are still only a limited number of reports concerning non-HLA susceptibility loci to TAK. We conducted a genome-wide association study (GWAS) and a follow-up study in a total of 633 TAK cases and 5,928 controls. A total of 510,879 SNPs were genotyped, and 5,875,450 SNPs were imputed together with HLA-B*52. Functional annotation of significant loci, enhancer enrichment, and pathway analyses were conducted. We identified four unreported significant loci, namely rs2322599, rs103294, rs17133698, and rs1713450, in PTK2B, LILRA3/LILRB2, DUSP22, and KLHL33, respectively. Two additional significant loci unreported in non-European GWAS were identified, namely HSPA6/FCGR3A and chr21q.22. We found that a single variant associated with the expression of MICB, a ligand for natural killer (NK) cell receptor, could explain the entire association with the HLA-B region. Rs2322599 is strongly associated with the expression of PTK2B Rs103294 risk allele in LILRA3/LILRB2 is known to be a tagging SNP for the deletion of LILRA3, a soluble receptor of HLA class I molecules. We found a significant epistasis effect between HLA-B*52 and rs103294 (P = 1.2 × 10-3). Enhancer enrichment analysis and pathway analysis suggested the involvement of NK cells (P = 8.8 × 10-5, enhancer enrichment). In conclusion, four unreported TAK susceptibility loci and an epistasis effect between LILRA3 and HLA-B*52 were identified. HLA and non-HLA regions suggested a critical role for NK cells in TAK.

Semiquantitative assessment of the relative apical sparing pattern of longitudinal strain for cardiac amyloidosis identification.

BACKGROUNDS: The relative apical sparing pattern (RASP) of left ventricular (LV) longitudinal strain (LS) is frequently associated with cardiac amyloidosis (CA). However, the visual assessment of RASP is inconsistent, and the quantitative assessment of RASP is time-consuming. This study aimed to compare assessments of RASP for the identification of CA with conventional assessments and investigate their reproducibility and relevance on the assessments. METHODS: Forty patients with biopsy-proven CA were compared with 80 hypertrophied patients matched for mean LV wall thickness. We compared the discriminative abilities of three assessments of RASP to identify CA (visual, quantitative, and semiquantitative). Nine patterns of semiquantitative RASP were investigated; finally, it was defined as "reduction of LS" (≥ -10%) in ≥5 (of 6) basal segments, relative to "preserved LS" (< -15%) in at least one apical segment. RESULTS: The concordance between the two observers for visual RASP was modest (κ = 0.65). On the other hand, the consistency for semiquantitative RASP was perfect (κ = 1.00). The discriminative ability of semiquantitative RASP (area under the curve [AUC]  = 0.74) was significantly better than that of visual RASP (AUC = 0.65) and equivalent to that of binary quantitative RASP. CONCLUSION: Semiquantitative RASP assessment is reproducible and accurately discriminates CA. This simple assessment may help readily refine the risk stratification of patients with diffuse LV hypertrophy.

Rural-Urban Disparity in Emergency Care for Acute Myocardial Infarction in Japan.

BACKGROUND: There are few reports examining regional differences between rural prefectures and metropolitan areas in the management of acute myocardial infarction (AMI) in Japan.Methods and Results:In the Rural AMI registry, a prospective, multi-prefectural registry of AMI in 4 rural prefectures (Ishikawa, Aomori, Ehime and Mie), a total of 1,695 consecutive AMI patients were registered in 2013. Among them, 1,313 patients who underwent primary percutaneous coronary intervention (PPCI) within 24 h of onset were enrolled in this study (Rural group), and compared with the cohort data from the Tokyo CCU Network registry for AMI in the same period (Metropolitan group, 2,075 patients). The prevalence of direct ambulance transport to PCI-capable facilities in the Rural group was significantly lower than that in the Metropolitan group (43.8% vs. 60.3%, P<0.01), which resulted in a longer onset-to-balloon time (OTB: 225 vs. 210 min, P=0.02) and lower prevalence of PPCI in a timely fashion (OTB ≤2 h: 11.5% vs. 20.7%, P<0.01) in the Rural group. Multivariate analysis revealed that direct ambulance transport was the strongest predictor for PPCI in a timely fashion (odds ratio=4.13, P<0.001). CONCLUSIONS: AMI patients in rural areas were less likely to be transported directly to PCI-capable facilities, resulting in time delay to PPCI compared with those in metropolitan areas.

Coronary artery-left ventricular shunt: an important cause of chest pain in patients with hypertrophic cardiomyopathy.

The influence of shunts between the coronary artery (CA) and the left ventricle (LV), on chest pain (CP) in patients with hypertrophic cardiomyopathy (HCM) is unknown. We examined the incidence of CA-LV shunts and their influence on CP in HCM patients. Twenty normal control subjects (NCS), 3 with CP due to CA-LV shunts (CP patients), and 60 with HCM participated. Interventricular septal wall thickness (IVST), LV posterior wall thickness (LVPWT), cardiac and stroke indexes (CI and SI), LV end-diastolic pressure (LVEDP), and proximal diameters of the CA were measured. Twenty-five HCM patients had a CA-LV shunt (41.7%). Both IVST and LVPWT were greater in the HCM patients than in NCS and CP patients. These values showed no significant differences between the HCM with shunt and HCM without shunt groups. CI and SI were lower in the HCM patients than in NCS and CP patients. LVEDP was higher in the HCM and CP patients than in NCS. CA diameters were larger in the HCM and CP patients than in NCS. CP was found in 32 HCM patients (53%). The incidence of CP was greater in the HCM with shunt group than in HCM without shunt group (80 vs. 34%, p < 0.0005). There was no significant difference in CA diameters between the HCM patients with CP and those without CP. CA-LV shunts are often found in HCM patients and are closely related to CP. Thus, CA-LV shunts are an important factor behind CP in HCM patients.

A Novel Truncating LMNA Mutation in Patients with Cardiac Conduction Disorders and Dilated Cardiomyopathy.

The cardiac phenotype of laminopathies is characterized by cardiac conduction disorders (CCDs) and dilated cardiomyopathy (DCM). Although laminopathies have been considered monogenic, they exhibit a remarkable degree of clinical variability. This case series aimed to detect the causal mutation and to investigate the causes of clinical variability in a Japanese family with inherited CCD and DCM.Of the five family members investigated, four had either CCD/DCM or CCD alone, while one subject had no cardiovascular disease and acted as a normal control. We performed targeted resequencing of 174 inherited cardiovascular disease-associated genes in this family and pathological mutations were confirmed using Sanger sequencing. The degree of clinical severity and variability were also evaluated using long-term medical records. We discovered a novel heterozygous truncating lamin A/C (LMNA) mutation (c.774delG) in all four subjects with CCD. Because this mutation was predicted to cause a frameshift mutation and premature termination (p.Gln258HisfsTer222) in LMNA, we believe that this LMNA mutation was the causal mutation in this family with CCD and laminopathies. In addition, gender-specific intra-familiar clinical variability was observed in this Japanese family where affected males exhibited an earlier onset of CCD and more severe DCM compared to affected females. Using targeted resequencing, we discovered a novel truncating LMNA mutation associated with CCD and DCM in this family characterized by gender differences in clinical severity in LMNA carriers. Our results suggest that in patients with laminopathy, clinical severity may be the result of multiple factors.

[A Case of Stage IV Breast Cancer with Long-Term Survival by Chemotherapy Developing Pulmonary Tumor Thrombotic Microangiopathy during the Treatment Course].

Pulmonary tumor thrombotic microangiopathy(PTTM)caused by pulmonary artery microscopic tumor emboli and fibrocellular and/or fibromuscular proliferation leads to progressive pulmonary hypertension and respiratory failure.The prognosis is extremely poor and most patients die shortly after onset.We report a patient with Stage IV breast cancer and long-term survival who developed PTTM during chemotherapy treatment.A 63-year-old woman with multiple metastases in her cerebellum, bone, lung, and lymph node after left breast conserving surgery started to experience dyspnea and malaise 7 years after the surgery.Two months later, she was urgently admitted to hospital because of respiratory failure and was diagnosed with pulmonary hypertension.However, pulmonary thrombosis and tumor thrombus were not observed.We clinically diagnosed her with PTTM and administered chemotherapy in addition to treatment for pulmonary hypertension.Her medical condition improved gradually and she survived for the subsequent 2 years.When observing progressive hypoxia and pulmonary hypertension without obvious pulmonary embolism findings on imaging, PTTM should be considered.Early diagnosis and immediate induction of chemotherapy for primary disease can improve the survival of patients with PTTM.

Differentiation of myocardial ischemia and infarction assessed by dynamic computed tomography perfusion imaging and comparison with cardiac magnetic resonance and single-photon emission computed tomography.

OBJECTIVES: To evaluate the feasibility of myocardial blood flow (MBF) by computed tomography from dynamic CT perfusion (CTP) for detecting myocardial ischemia and infarction assessed by cardiac magnetic resonance (CMR) or single-photon emission computed tomography (SPECT). METHODS: Fifty-three patients who underwent stress dynamic CTP and either SPECT (n = 25) or CMR (n = 28) were retrospectively selected. Normal and abnormal perfused myocardium (ischemia/infarction) were assessed by SPECT/CMR using 16-segment model. Sensitivity and specificity of CT-MBF (mL/g/min) for detecting the ischemic/infarction and severe infarction were assessed. RESULTS: The abnormal perfused myocardium and severe infarction were seen in SPECT (n = 90 and n = 19 of 400 segments) and CMR (n = 223 and n = 36 of 448 segments). For detecting the abnormal perfused myocardium, sensitivity and specificity were 80 % (95 %CI, 71-90) and 86 % (95 %CI, 76-91) in SPECT (cut-off MBF, 1.23), and 82 % (95 %CI, 76-88) and 87 % (95 %CI, 80-92) in CMR (cut-off MBF, 1.25). For detecting severe infarction, sensitivity and specificity were 95 % (95 %CI, 52-100) and 72 % (95 %CI, 53-91) in SPECT (cut-off MBF, 0.92), and 78 % (95 %CI, 67-97) and 80 % (95 %CI, 58-86) in CMR (cut-off MBF, 0.98), respectively. CONCLUSIONS: Dynamic CTP has a potential to detect abnormal perfused myocardium and severe infarction assessed by SPECT/CMR using comparable cut-off MBF. KEY POINTS: • CT-MBF accurately reflects the severity of myocardial perfusion abnormality. • CT-MBF provides good diagnostic accuracy for detecting myocardial perfusion abnormalities. • CT-MBF may assist in stratifying severe myocardial infarction in abnormal perfusion myocardium.

Clinical Significance of Peripheral Endothelial Function for Left Atrial Blood Stagnation in Nonvalvular Atrial Fibrillation Patients With Low-to-Intermediate Stroke Risk.

BACKGROUND: In patients who have atrial fibrillation (AF) with CHADS2score of 0-1 (categorized as low-to-intermediate risk), there is little information on stratifying the risk of stroke. This study aimed to determine whether impaired endothelial function assessed by reactive hyperemia-peripheral arterial tonometry (RH-PAT) predicted left atrial blood stagnation in these patients. METHODS AND RESULTS: We enrolled 81 consecutive patients with nonvalvular AF. The reactive hyperemia index (RHI) was measured using RH-PAT. Transesophageal echocardiography was performed to determine spontaneous echo contrast (SEC) before direct-current cardioversion or radiofrequency catheter ablation. SEC was found in 49 patients (60%). The RHI was significantly lower in patients with than without SEC. Multivariate analysis demonstrated that RHI was one of the independent determinants of SEC (OR per 0.1, 1.26; 95% CI, 1.11-1.49; P=0.002) in all patients. In addition, RHI was a significant determinant of SEC (AUC, 0.73; 95% CI, 0.63-0.89; P=0.0017) in patients with low-to-intermediate risk. At an RHI cut-off <1.62, the sensitivity and specificity for the identification of patients with SEC were 58% and 89%, respectively. CONCLUSIONS: Impaired endothelial function assessed by RH-PAT might help to predict the presence of SEC in patients with low-to-intermediate risk of stroke. (Circ J 2016; 80: 2117-2123).

Clinical Utility of Atrial Electromechanical Conduction Time Measured with Speckle Tracking Echocardiography after Catheter Ablation in Patients with Atrial Fibrillation: A Validation Study with Electroanatomical Mapping.

PURPOSE: Our recent report demonstrated that atrial electromechanical conduction time (EMT-ε) measured with speckle tracking echocardiography could predict cardiac events in patients with pathological left ventricular hypertrophy. This study aimed to validate EMT-ε by comparison with electroanatomical mapping and to investigate the clinical utility of EMT-ε in patients with atrial fibrillation (AF) undergoing catheter ablation. METHODS: Forty-six patients with preserved LV ejection fraction (LVEF ≥ 50%) undergoing pulmonary vein isolation (PVI) for AF were studied. Atrial electrical conduction delay was determined by measuring atrial electrical activation time (EAT) using three-dimensional electroanatomical mapping just after PVI. Echocardiographic parameters were acquired within 24 hours and at 6 months after PVI. The study also included 10 control subjects. RESULTS: AF patients had a larger left atrial (LA) volume index (LAVI) and more prolonged EMT-ε compared with control subjects. According to the validation study, EAT was closely related to EMT-ε and a', and this association was independent of LAVI and the presence of persistent AF (EMT-ε: R(2) = 0.342, P < 0.0001, a': R(2) = 0.337, P < 0.0001). At 6 months after PVI, LAVI and EMT-ε were significantly improved. During continued follow-up beyond 6 months (total follow-up, 26 ± 12 months), the EMT-ε shortening at 6 months after PVI was significantly greater in AF-free patients than patients with AF recurrence. CONCLUSIONS: This study suggested that the EMT-ε could be a useful echocardiographic marker of LA electromechanical abnormalities in patients with AF.

Characteristics of Left Atrial Deformation Parameters and Their Prognostic Impact in Patients with Pathological Left Ventricular Hypertrophy: Analysis by Speckle Tracking Echocardiography.

BACKGROUND: The pathological process of left ventricular (LV) hypertrophy is associated with left atrial (LA) remodeling. This study was aimed to evaluate the prognostic value of LA strain parameters in patients with pathological LV hypertrophy. METHODS: This study included 95 patients with hypertensive heart disease (HHD: n = 24), hypertrophic cardiomyopathy (HCM: n = 56), cardiac amyloidosis (CA: n = 15), and control subjects (n = 20). We used two-dimensional speckle tracking echocardiography (STE) to analyze LA global strain. LA electromechanical conduction time (EMT) at the septal (EMT-septal) and lateral wall (EMT-lateral), and their time difference (EMT-diff) were calculated. The incidence of cardiac death and heart failure hospitalization was defined as major cardiac events and that of atrial fibrillation as secondary outcome. RESULTS: Left atrial volume index was increased and LA booster strain was decreased in the HCM and CA groups compared with the HHD group. EMT-lateral was increased in the diseased groups compared with the control. EMT-diff was prolonged in the CA group compared with the HCM group. During the follow-up period (mean 3.4 years), major cardiac events and atrial fibrillation occurred in 17 and 13 patients, respectively. The occurrence of atrial fibrillation was associated with CA etiology, E/e', LA volume index, LAa, and EMT-lateral. The incidence of major cardiac events was independently correlated with LA volume index and EMT-diff in multivariate analysis. CONCLUSION: This study suggested that the EMT-diff could discriminate patients with a high risk of cardiac events among patients with pathological LV hypertrophy.

Association Between Genetic Variation in the SCN10A Gene and Cardiac Conduction Abnormalities in Patients With Hypertrophic Cardiomyopathy.

Arrhythmias are associated with reduced quality of life and poor prognosis in patients with hypertrophic cardiomyopathy (HCM). Recent genome-wide association studies revealed that a nonsynonymous single nucleotide polymorphism, rs6795970, in the SCN10A gene was associated with the PR interval. We examined whether the PR prolonging allele (A allele) in the SCN10A gene may be associated with cardiac conduction abnormalities in HCM patients.We genotyped the polymorphism in 149 HCM patients. Conduction abnormalities were defined as first-degree heart block, bundle-branch block, and bifascicular heart block. Patients were divided into two groups: group A consisted of 122 patients (82%) without a conduction abnormality; and group B consisted of 27 patients (18%) with one or more cardiac conduction abnormalities. The frequency distribution of the SCN10A genotypes (G/G, G/A, and A/A) among the patients with HCM was 71%, 26%, and 3%, respectively. A cardiac conduction abnormality was documented in 9% with G/G and 40% with G/A or A/A. There was a significant difference in the genotype distribution between the two groups (P = 0.0002). In the dominant A allele model, there was a significant difference in genotypes between the two groups (P < 0.0001). In addition, the A allele remained significant after adjusting for other covariates in a multivariate model (odds ratio = 6.30 [95% confidence interval: 2.24 to 19.09], P = 0.0005).The rs6795970 in the SCN10A gene, which is reported to carry a high risk of heart block, might be associated with cardiac conduction abnormalities in HCM patients.

Positron emission tomography-computed tomography for imaging of inflammatory cardiovascular diseases.

Inflammation is a determinant of atherosclerotic plaque rupture, the event usually responsible for myocardial infarction and stroke. Possible causes of inflammatory cardiomyopathy include myocarditis, eosinophilic disease, and sarcoidosis. Although conventional imaging techniques can identify the site and severity of luminal stenosis, they do not provide information regarding inflammatory status. (18)F-fluorodeoxyglucose (FDG) positron emission tomography (PET) for imaging of inflammatory cardiovascular diseases has been rapidly evolving. Integrated PET/computed tomography (CT) is becoming the method of choice for quantification of arterial inflammation across multiple vessels. Moreover, PET/CT provides information about the activation status of inflammatory cells in the vessel wall, thus allowing early diagnosis and risk stratification of patients. The Japanese health insurance system approved reimbursement for FDG-PET use to detect inflammation sites in cardiac sarcoidosis as of April 2012. This approval has necessitated a more detailed assessment of the clinical value of FDG-PET. Standardized preparation, imaging, and image interpretation protocols should be established to sufficiently suppress physiological FDG uptake in the normal myocardium, and thereby facilitate detection of early-stage cardiac inflammatory lesions with more favorable specificity. This review summarizes the background, clinical utility, state-of-the-art advances, and potential future applications of FDG-PET for imaging inflammatory cardiovascular diseases including cardiac sarcoidosis, large-vessel arteritis, and atherosclerosis.

Optimization of coronary attenuation in coronary computed tomography angiography using diluted contrast material.

BACKGROUND: The purpose of this study was to evaluate a personalized protocol with diluted contrast material (CM) for coronary computed tomography angiography (CTA). METHODS AND RESULTS: One hundred patients with suspected coronary artery disease underwent retrospective electrocardiogram-gated coronary CTA on a 256-slice multidetector-row CT scanner. In the diluted CM protocol (n=50), the optimal scan timing and CM dilution rate were determined by the timing bolus scan, with 20% CM dilution (5ml/s during 10s) being considered suitable to achieve the target arterial attenuation of 350 Hounsfield units (HU). In the body weight (BW)-adjusted protocol (n=50, 222mg iodine/kg), only the optimal scan timing was determined by the timing bolus scan. The injection rate and volume in the timing bolus scan and real scan were identical between the 2 protocols. We compared the means and variations in coronary attenuation between the 2 protocols. Coronary attenuation (mean±SD) in the diluted CM and BW-adjusted protocols was 346.1±23.9 HU and 298.8±45.2 HU, respectively. The diluted CM protocol provided significantly higher coronary attenuation and lower variance than did the BW-adjusted protocol (P<0.05, in each). CONCLUSIONS: The diluted CM protocol facilitates more uniform attenuation on coronary CTA in comparison with the BW-adjusted protocol.

Combined supine and prone myocardial perfusion single-photon emission computed tomography with a cadmium zinc telluride camera for detection of coronary artery disease.

BACKGROUND: Myocardial perfusion SPECT (MPS) traditionally requires the patient to be in the supine position, but diaphragmatic attenuation of the inferior wall reduces test specificity. The aim of this study was to assess the feasibility of combined MPS in the supine and prone positions using a novel cadmium zinc telluride (CZT) camera. METHODS AND RESULTS: A total of 276 consecutive patients with suspected/known coronary artery disease (CAD) who underwent single-day (99m)Tc-tetrofosmin or (99m)Tc-sestamibi stress/rest CZT SPECT, were enrolled in the study. Seventy-six underwent coronary angiography. Five-minute scan in the supine (S) position and thereafter in the prone (P) position produced images that were visually interpreted to obtain summed stress (SSS) and rest (SRS) scores. A combined stress score (C-SSS) was calculated by grouping anterior perfusion defects observed during supine imaging with inferior half segments observed during prone imaging. The SSS for the supine, prone, and combined protocols were 9±8, 7±8, and 7±8, respectively (P<0.0001). The SRS were 5±8, 4±7, and 6±7, respectively (P=0.005). The area under the ROC curve for the S-SSS, P-SSS, and C-SSS scores was 0.815 (95% CI: 0.713-0.917), 0.813 (0.711-0.914), and 0.872 (0.783-0.961), respectively. Corresponding sensitivities and specificities for detecting CAD were 87% and 50%, 80% and 77%, and 85% and 82%, respectively. C-SSS had significantly better specificity and accuracy than S-SSS (P<0.05). CONCLUSIONS: Combined imaging with a CZT camera is suitable for routine clinical MPS and provides greater diagnostic accuracy than supine imaging alone.

[Anticoagulant therapy with dabigatran in elderly patients ≥80 years of age with atrial fibrillation].

AIM: Atrial fibrillation is a potent risk factor for stroke, and the administration of anticoagulant therapy is important for preventing thromboembolism. Dabigatran is the first new oral anticoagulant developed as an alternative to warfarin. However, serious major gastrointestinal bleeding events have been observed in elderly patients in post-market case reports. We therefore retrospectively investigated elderly cases of the use of anticoagulant therapy with dabigatran. METHODS: Twenty-eight patients over 80 years of age were treated with anticoagulant therapy at our satellite hospital. Nine of the patients received dabigatran, and all others received warfarin. We evaluated the CHADS2 score, HAS-BLED score, renal function and incidence of adverse effects in nine patients treated with dabigatran. RESULTS: All of the nine patients received 220 mg/day of dabigatran, with no antiplatelet agents. Seven patients continued to receive dabigatran. One patient had an impaired renal function (Cr 1.55 mg/dl, Ccr 30 ml/min). However, the activated partial thromboplastin time (APTT) was not prolonged and neither major bleeding nor stroke were noted in seven patients. Although two patients were unable to continue dabigatran treatment due to APTT prolongation, no serious complications were observed during the administration of dabigatran. CONCLUSIONS: No serious adverse effects of dabigatran anticoagulant therapy were detected in our elderly patients. Although it is necessary to monitor the risk of bleeding, renal dysfunction, effects of drug combination and so on, some elderly patients with atrial fibrillation are good candidates for dabigatran treatment.