Association of left atrial enlargement with heart failure events in non-valvular atrial fibrillation patients with preserved left ventricular ejection fraction

Aims

Atrial fibrillation (AF) increases the risk of heart failure (HF); however, little is known regarding the risk stratification for incident HF in AF patients, especially with preserved left ventricular ejection fraction (LVEF).

Methods and results

The Fushimi AF Registry is a community-based prospective survey of AF patients. From the registry, 3002 non-valvular AF patients with preserved LVEF and with the data of antero-posterior left atrial diameter (LAD) at enrolment were investigated. Patients were stratified by LAD (<40, 40-44, 45-49, and ≥50 mm) with backgrounds and HF hospitalization incidences compared between groups. Of 3002 patients [mean age, 73.5 ± 10.7 years; women, 1226 (41%); paroxysmal AF, 1579 (53%); and mean CHA2DS2-VASc score, 3.3 ± 1.7], the mean LAD was 43 ± 8 mm. Patients with larger LAD were older and less often paroxysmal AF, with a higher CHA2DS2-VASc score (all P < 0.001). Heart failure hospitalization occurred in 412 patients during the median follow-up period of 6.0 years. Larger LAD was independently associated with a higher HF hospitalization risk [LAD ≥ 50 mm: hazard ratio (HR), 2.36; 95% confidence interval (CI), 1.75-3.18; LAD 45-49 mm: HR, 1.84; 95% CI, 1.37-2.46; and LAD 40-44 mm: HR, 1.34; 95% CI, 1.01-1.78, compared with LAD < 40 mm) after adjustment by age, sex, AF type, and CHA2DS2-VASc score. These results were also consistent across major subgroups, showing no significant interaction.

Conclusion

Left atrial diameter is significantly associated with the risk of incident HF in AF patients with preserved LVEF, suggesting the utility of LAD regarding HF risk stratification for these patients.

Proteinuria is independently associated with heart failure events in patients with atrial fibrillation: the Fushimi AF registry

AIMS

Previous studies have shown that proteinuria is independently associated with the incidence of atrial fibrillation (AF), and is also associated with the incidence of cardiovascular events such as stroke and thromboembolism in patients with AF. However, the association of proteinuria with heart failure (HF) events in patients with AF remains unclear.

METHODS AND RESULTS

The Fushimi AF Registry is a community-based prospective study of patients with AF. Of the entire cohort of 4489 patients, 2164 patients had available data of proteinuria. We compared the clinical background and outcomes between patients with proteinuria (n = 606, 28.0%) and those without (n = 1558, 72.0%). Patients with proteinuria were older and had a higher prevalence of major co-morbidities. During the median follow-up of 5.0 years, the incidence rates of HF events (composite of cardiac death or HF hospitalization) were higher in patients with proteinuria than those without (4.1% vs. 2.1% person-year, P < 0.01). Multivariate analyses revealed that proteinuria was an independent risk factor of the incidence of HF events [adjusted hazard ratio (HR): 1.40, 95% confidence interval (CI): 1.13-1.74]. This association was consistent among the various subgroups, except for the age subgroup in which there was a significant interaction (P < 0.01) between younger (<75 years) (unadjusted HR: 3.03, 95% CI: 2.12-4.34) and older (≥75 years) patients (unadjusted HR: 1.59, 95% CI: 1.23-2.05).

CONCLUSION

Our community-based large prospective cohort suggests that proteinuria is independently associated with the incidence of HF events in Japanese patients with AF.

Utility of left ventricular ejection fraction in atrial fibrillation patients without pre-existing heart failure

AIMS

Atrial fibrillation (AF) increases the risk of heart failure (HF); however, little focus has been placed on the prevention of HF in patients with AF. Left ventricular ejection fraction (LVEF) is an established echocardiographic parameter in HF patients. We sought to investigate the association of LVEF with HF events in AF patients without pre-existing HF.

METHODS AND RESULTS

The Fushimi AF Registry is a community-based prospective survey of AF patients in Fushimi-ku, Japan. In this analysis, we excluded patients with pre-existing HF (defined as having one of the following: prior HF hospitalization, New York Heart Association class ≥ 2 in association with heart disease, or LVEF < 40%). Among 3233 AF patients without pre-existing HF, we investigated 2459 patients with the data of LVEF at enrolment. We divided the patients into three groups stratified by LVEF [mildly reduced LVEF (40-49%), below normal LVEF (50-59%), and normal LVEF (≥60%)] and compared the backgrounds and incidence of HF hospitalization between the groups. Of 2459 patients [mean age: 72.4 ± 10.5 years, female: 917 (37%), paroxysmal AF: 1405 (57%), and mean CHA2 DS2 -VASc score: 3.0 ± 1.6], the mean LVEF was 66 ± 8% [mildly reduced LVEF: 114 patients (5%), below normal LVEF: 300 patients (12%), and normal LVEF: 2045 patients (83%)]. Patients with lower LVEF demonstrated lower prevalence of female and paroxysmal AF (both P < 0.01), but age and CHA2 DS2 -VASc score were comparable between the three groups (both P > 0.05). During the median follow-up period of 6.0 years, 255 patients (10%) were hospitalized for HF (annual incidence: 1.9% per person-year). Multivariable Cox regression analysis demonstrated that lower LVEF strata were independently associated with the risk of HF [mildly reduced LVEF (40-49%): hazard ratio = 2.98, 95% confidence interval = 1.99-4.45 and below normal LVEF (50-59%): hazard ratio = 2.01, 95% confidence interval = 1.44-2.82, compared with normal LVEF (≥60%)] after adjustment by age, sex, type of AF, and CHA2 DS2 -VASc score. LVEF < 60% was significantly associated with the higher risk of HF hospitalization across all major subgroups without significant interaction (P for interaction; all P > 0.05). LVEF had an independent and incremental prognostic value for HF hospitalization in addition to natriuretic peptide levels in AF patients without pre-existing HF.

CONCLUSIONS

Lower LVEF was significantly associated with the higher incidence of HF hospitalization in AF patients without pre-existing HF, leading to the future risk stratification for and prevention of incident HF in AF patients.

Comparison of the acceptability and safety of molnupiravir in COVID-19 patients aged over and under 80 years

Background

Molnupiravir is being widely used as a treatment for coronavirus disease 2019 (COVID-19); however, its acceptability and safety in older patients aged ≥ 80 years in real-world clinical practice is not well understood.

Methods

We conducted a single-centre retrospective study and assessed the outcome of patients with COVID-19 treated with molnupiravir according to the following criteria: (A) discontinuation rate of molnupiravir; (B) type, frequency, and severity of adverse events; (C) all-cause mortality within 30 days of the diagnosis of COVID-19.

Results

Forty-seven patients (46.1%) were aged ≥ 80 years (older patients) and 55 (53.9%) were aged < 80 years (younger patients). There were no significant differences in coexisting diseases and history of vaccination for COVID-19 between older and younger patients. Older patients were significantly more likely to have moderate disease (moderate 1 and 2) according to the Japanese Ministry of Health, Labour and Welfare classification than younger patients. During treatment, 8.5% of older patients and 1.8% of younger patients stopped taking molnupiravir, but the difference was not significant. Adverse events were observed in 39/102 (38.2%) patients. The most common adverse events were diarrhoea (9.8%), exacerbation of coexisting diseases (6.9%), bone marrow suppression (6.9%), liver dysfunction (5.9%), and loss of appetite (4.9%). Most adverse events were minor, ranging from grades 1 to 3. The all-cause mortality rate was 10.8%, and no molnupiravir-related deaths were observed.

Conclusions

Molnupiravir treatment is acceptable and safe in older patients with COVID-19 aged ≥ 80 years.

Effect of iodine concentration and body size on iodine subtraction in virtual non-contrast imaging: A phantom study

INTRODUCTION

Dual-energy computed tomography (DECT) can generate virtual non-contrast (VNC) images. Herein, we sought to improve the accuracy of VNC images by identifying the optimal slope of contrast media (SCM) for VNC-image generation based on the iodine concentration and subject's body size.

METHODS

We used DECT to scan a multi-energy phantom including four iodine concentration rods (15, 10, 5, and 2 mg/mL), and 240 VNC images (eight SCM ranging from 0.49 to 0.56 × three body sizes × ten scans) that were generated by three-material decomposition. The CT number of each iodine and solid water rod part was measured in each VNC image. The difference in the CT number between the iodine and the solid water rod part was calculated and compared using paired t-test or repeated measures ANOVA.

RESULTS

The SCM that achieved an absolute value of the difference in CT number of <5.0 Hounsfield units (HU) for all body sizes simultaneously was greater at lower iodine concentration (SCM of 0.5, 0.51, and 0.53 at 10, 5, and 2 mg/mL iodine, respectively). At an iodine concentration of 15 mg/mL, no SCM achieved an absolute difference of <5.0 HU in CT number for all body sizes simultaneously. At all iodine concentrations, the SCM achieving the minimal difference in the CT number increased with the increase in body size.

CONCLUSION

By adjusting the SCM according to the iodine concentration and body size, it is possible to generate VNC images with an accuracy of <5.0 HU.

IMPLICATIONS FOR PRACTICE

Improving the accuracy of VNC images minimizing incomplete iodine subtraction would make it possible to replace true non-contrast (TNC) images with VNC images and reduce the radiation dose.

Association of cardiothoracic ratio with heart failure hospitalization in patients with atrial fibrillation: the Fushimi AF Registry

Background

Chest radiography is the most common diagnostic imaging test in clinical medicine, and the cardiothoracic ratio (CTR) is a readily available and non-invasive tool with which to assess the volume status and cardiomegaly. However, it remains unknown whether CTR on chest radiography is associated with the incidence of HF hospitalization in AF patients remains unclear.

Methods

The Fushimi AF Registry is a community-based prospective survey of AF patients in Fushimi-ku, Kyoto, Japan. The inclusion criterion of the registry is the documentation of AF at 12-lead electrocardiogram or Holter monitoring at any time, and there are no exclusion criteria. We started to enroll patients from March 2011, and follow-up data were available for 4,489 patients by the end of August 2021. In the present study, 3,727 patients with available data of CTR were examined. We divided the patients into two groups according to their CTR at baseline; Higher group (CTR ≥50.0%, n=2,696) and Lower group (CTR &lt;50.0%, n=1,031), and compared the clinical background and outcomes between the two groups.

Results

The proportion of female was grater in Higher group, and the patients in Higher group were older. The patients in Higher group had higher prevalence of HF, hypertension and chronic kidney disease. During the median follow-up of 3,033 days, in Kaplan-Meier analysis, the incidence rates of HF hospitalization were higher in Higher group (Higher group: 2.5% per person-year vs. Lower group: 1.1%; p&lt;0.01). Multivariate Cox proportional hazards regression analysis revealed that higher CTR (≥50.0%) was an independent determinant of the incidence of HF hospitalization. Furthermore, when we divided the patients into four groups based on the quartile of CTR; Q1 (CTR&lt;49.0%), Q2 (49.0≤CTR&lt;53.8%), Q3 (53.8≤CTR&lt;59.0%), Q4 (59.0%≤CTR), the incidence of HF hospitalization was more frequent in patients with higher CTR, regardless of the presence or absence of prior hospitalization for HF (Figure).

Conclusion

In Japanese AF patients, patients with higher CTR had significantly higher incidence of HF hospitalization, regardless of the prevalence of prior hospitalization for HF.

Funding Acknowledgement

Type of funding sources: None.

The association of left ventricular ejection fraction with incident heart failure in patients with atrial fibrillation

Background

Atrial fibrillation (AF) increases the risk of incident heart failure (HF). Left ventricular ejection fraction (LVEF) is an important prognostic parameter in patients with HF. However, little is known regarding the association of LVEF with incident HF in patients with AF.

Purpose

The aim of this study is to investigate the relationship between LVEF at enrollment and incidence of HF hospitalization during follow-up period in patients with AF.

Methods

The Fushimi AF Registry is a community-based prospective survey of patients with AF in Fushimi-ku, Kyoto, Japan. The inclusion criterion of the registry is the documentation of AF at 12-lead electrocardiogram or Holter monitoring at any time, and there are no exclusion criteria. We started to enroll patients from March 2011, and follow-up data were available for 4,489 patients by the end of August 2021. In the present study, we investigated 3,544 patients with the data of LVEF at enrollment. We divided the patients into 4 groups stratified by LVEF (reduced LVEF [LVEF &lt;40%], mildly reduced LVEF [LVEF: 40–49%], slightly reduced LVEF [LVEF: 50–59%], and normal LVEF [LVEF ≥60%]), and compared the backgrounds and outcomes between these 4 groups.

Results

Of 3,544 patients, the mean age was 73.6±10.7 years, 1,420 (40%) were female, 1,781 (50%) were paroxysmal AF, and 1,085 (30%) had pre-existing HF. The mean CHADS2 and CHA2DS2-VASc scores were 2.1±1.3 and 3.4±1.7, respectively. The mean LVEF at enrollment was 63±12% (reduced LVEF: 197 [6%], mildly reduced LVEF: 250 [7%], slightly reduced LVEF: 532 [15%] and normal LVEF: 2,565 [72%], respectively). Patients with lower LVEF demonstrated lower prevalence of female and paroxysmal AF, and had a higher CHADS2 and CHA2DS2-VASc scores (all P&lt;0.01). A total of 605 patients were hospitalized for HF during the median follow-up period of 5.5 years, corresponding to an annual incidence of 3.4% per person-year. Kaplan-Meier curves demonstrated that LVEF at enrollment could stratify the incidence of HF hospitalization during follow-up in patients with AF (Picture 1). Multivariable Cox regression analysis revealed that lower LVEF strata were significantly associated with the increased risk of HF hospitalization even after adjustment by age, sex, type of AF and CHA2DS2-VASc score (Picture 1). An increased risk of HF hospitalization was observed even in patients with mildly reduced LVEF (adjusted hazard ratio: 2.56, 95% CI: 1.99–3.29) as well as in those with slightly reduced LVEF (adjusted hazard ratio: 1.79, 95% CI: 1.45–2.22) compared with those with normal LVEF. These results were also the case in AF patients without pre-existing HF (Picture 2).

Conclusion

LVEF at enrollment could stratify the incidence of HF hospitalization in patients with AF, suggesting the importance of measuring LVEF in all patients with AF. Even mildly (LVEF: 40–49%) or slightly (LVEF: 50–59%) reduced LVEF was independently associated with the risk of incident HF in patients with AF.

Funding Acknowledgement

Type of funding sources: None.

Association of Concomitant Coronary Artery Disease With Cardiovascular Events in Patients With Atrial Fibrillation - The Fushimi AF Registry

BACKGROUND

Atrial fibrillation (AF) patients often have concomitant coronary artery disease (CAD); however, there are little data on clinical characteristics and outcomes of such patients in daily clinical practice in Japan.Methods and Results: The Fushimi AF Registry is a community-based prospective survey of AF patients in Fushimi-ku, Kyoto, Japan. Follow-up data were available for 4,464 patients, and the median follow up was 5.1 (interquartile range: 2.3-8.0) years. History of CAD was present in 647 patients (14%); of those patients, 267 (41%) had history of myocardial infarction (MI). Patients with CAD were older and had more comorbidities than those without CAD. The crude incidences (% per patient-year) of cardiovascular events were significantly higher in patients with CAD than those without CAD (cardiac death: 1.8 vs. 0.7, stroke or systemic embolism [SE]: 2.9 vs. 2.1, MI: 0.6 vs. 0.1, composite of those events: 5.1 vs. 2.8, respectively, all log-rank P<0.01). After multivariate adjustment, concomitant CAD was associated with incidence of cardiac events, and history of MI was associated with incidence of MI; however, neither history of CAD nor MI was associated with the incidence of stroke/SE.

CONCLUSIONS

In Japanese AF patients, concomitant CAD was associated with higher prevalences of major co-morbidities and higher incidences of cardiovascular events; however, history of CAD was not associated with the incidence of stroke/SE.

Isometric Handgrip Stress Test during Right Heart Catheterization in Patients with Mitral Regurgitation -A Case Series Study

Objective The severity of mitral regurgitation (MR) dynamically changes during a stress test. Isometric handgrip is a readily-available stress test in daily practice; however, little is known regarding the response to isometric handgrip in MR patients during right heart catheterization. We aimed to evaluate this issue from our case-series study. Methods We retrospectively investigated consecutive MR patients using the isometric handgrip stress test during right heart catheterization at our institution between October 2019 and April 2021. After resting measurements were obtained, sustained maximum-effort hand dynamometer grasping was maintained for about 2-3 minutes. We investigated the differences in right heart catheterization data between at rest and during handgrip, and evaluated the individual response to the isometric handgrip stress test. Results We investigated a total of 15 patients (mean age: 75±6 years, moderate/severe MR: 7/8, primary/secondary MR: 8/7, mean left ventricular ejection fraction: 56±16%, exertional dyspnea: 10). During the handgrip test, the pulmonary capillary wedge pressure (PCWP) significantly increased [9 (8, 13) mmHg at rest to 20 (15, 27) mmHg during handgrip; p<0.001]. PCWP changes varied among individuals (range 2-22 mmHg) and were not correlated with patients' backgrounds including age, the natriuretic peptide levels, left ventricular ejection fraction, left atrial diameter or E/e' (all p>0.05). Patients with PCWP ≥25 mmHg during handgrip had a higher prevalence of exertional dyspnea than those without [6 (100%) vs. 4 (44%); p=0.04]. Conclusion We observed dynamic and varied hemodynamic changes during isometric handgrip in MR patients, suggesting that further research is needed to evaluate the clinical value of this maneuver.

Prediction of pathological response to preoperative chemotherapy for pancreatic ductal adenocarcinoma using 2-[18F]-fluoro-2-deoxy-d-glucose positron-emission tomography

AIM

To determine whether the pathological response to preoperative chemotherapy for pancreatic ductal adenocarcinoma (PDAC) can be predicted using 2-[18F]-fluoro-2-deoxy-d-glucose positron-emission tomography (F-18 FDG-PET).

MATERIALS AND METHODS

Twenty-eight patients with PDAC who underwent only neoadjuvant chemotherapy (NAC) before surgery were enrolled in the study. All patients had F-18 FDG-PET examinations before NAC. The resected specimen was pathologically evaluated according to the Classification of Pancreatic Carcinoma (7th edn). Patients were categorised into a non-response group and a response group based on the pathological findings. The non-response group (Grades 1a and 1b) showed ≤50% necrosis in the specimen, while the specimens of the response group (Grades 2-3) showed >50% necrosis. The maximum standardised uptake values (SUVmax) of the tumours on F-18 FDG-PET were measured. The mean values of SUVmax were compared between the two groups. The diagnostic performance of SUVmax in distinguishing the two groups was also evaluated using receiver operating characteristic analysis.

RESULTS

The mean SUVmax of the response group was higher than that of the non-response group (9.00 ± 1.78 versus 4.26 ± 2.35; p<0.001). The optimal cut-off value of SUVmax was 9.28 for distinguishing the two groups. The sensitivity, specificity, and accuracy for the prediction in the response group were 80%, 95.7%, and 92.9%, respectively.

CONCLUSIONS

SUVmax on F-18 FDG-PET may be useful as a biomarker to predict the pathological response to NAC in patients with PDAC.

Vessel-Selective 4D-MRA Using Superselective Pseudocontinuous Arterial Spin-Labeling with Keyhole and View-Sharing for Visualizing Intracranial Dural AVFs

BACKGROUND AND PURPOSE

An accurate assessment of the hemodynamics of an intracranial dural AVF is necessary for treatment planning. We aimed to investigate the utility of 4D-MRA based on superselective pseudocontinuous arterial spin-labeling with CENTRA-keyhole and view-sharing (4D-S-PACK) for the vessel-selective visualization of intracranial dural AVFs.

MATERIALS AND METHODS

We retrospectively analyzed the images of 21 patients (12 men and 9 women; mean age, 62.2 [SD,19.2] years) with intracranial dural AVFs, each of whom was imaged with DSA, 4D-S-PACK, and nonselective 4D-MRA based on pseudocontinuous arterial spin-labeling combined with CENTRA-keyhole and view-sharing (4D-PACK). The shunt location, venous drainage patterns, feeding artery identification, and Borden classification were evaluated by 2 observers using both MRA methods on separate occasions. Vessel selectivity was evaluated on 4D-S-PACK.

RESULTS

Shunt locations were correctly evaluated in all 21 patients by both observers on both MRA methods. With 4D-S-PACK, observers 1 and 2 detected 76 (80.0%, P < .001) and 73 (76.8%, P < .001) feeding arteries of the 95 feeding arteries identified on DSA but only 39 (41.1%) and 46 (48.4%) feeding arteries with nonselective 4D-PACK, respectively. Both observers correctly identified 10 of the 11 patients with cortical venous reflux confirmed by DSA with both 4D-S-PACK and 4D-PACK (sensitivity = 90.9%, specificity = 90.9% for each method), and they made accurate Borden classifications in 20 of the 21 patients (95.2%) on both MRA methods. Of the 84 vessel territories examined, vessel selectivity was graded 3 or 4 in 73 (91.2%) and 66 (88.0%) territories by observers 1 and 2, respectively.

CONCLUSIONS

4D-S-PACK is useful for the identification of feeding arteries and accurate classifications of intracranial dural AVFs and can be a useful noninvasive clinical tool.

Clinical Characteristics and Outcomes of Very Elderly Patients With Atrial Fibrillation at High Bleeding Risk - The Fushimi AF Registry

Background: The ELDERCARE-AF trial demonstrated that low-dose edoxaban prevented stroke or systemic embolism (SE) in very elderly Japanese patients with non-valvular atrial fibrillation (NVAF) in whom standard oral anticoagulant therapy was inappropriate because of high bleeding risk. The aim of this study was to elucidate the characteristics and outcomes of such patients in routine clinical practice.

Methods and Results: Data were extracted from the Fushimi AF Registry for ELDERCARE-eligible NVAF patients aged ≥80 years, with a CHADS₂ score ≥2 and ≥1 bleeding risk factors, as shown in the ELDERCARE-AF trial. ELDERCARE-eligible patients (n=549; 12.8% of the entire cohort, 52.9% of those aged ≥80 years and with CHADS₂ score ≥2) were less often male, were older, had more comorbidity and higher risk scores than non-eligible patients from the entire cohort (n=3,734). The crude incidence (% per patient-year) of adverse events was significantly higher in ELDERCARE-eligible than non-eligible patients (stroke/SE, 4.8% vs. 2.0%; major bleeding, 3.6% vs. 1.9%; all-cause mortality, 15.5% vs. 3.9%; cardiovascular death, 2.7% vs. 0.6%; all log-rank P<0.001). Compared with non-eligible patients aged ≥80 years and with a CHADS₂ score ≥2 (n=488), the incidence of stroke/SE, all-cause mortality, and cardiovascular death remained significantly higher in ELDERCARE-eligible patients.

Conclusions: Patients with NVAF who met the inclusion criteria of the ELDERCARE-AF trial were common in routine clinical practice, and had poor clinical outcomes.

The relationship between diastolic blood pressure and the risk of cardiovascular events in patients with atrial fibrillation whose systolic blood pressure was treated to less than 130 mmHg

Background

Hypertension is one of the major risk factors of cardiovascular events in patients with atrial fibrillation (AF). Low diastolic blood pressure (DBP) has been reported to be associated with the incidence of cardiovascular events, but current guidelines recommend an intensive blood pressure target of less than 130/80 mmHg for AF patients taking oral anticoagulants without mentioning the lower limits of DBP.

Methods

The Fushimi AF Registry is a community-based prospective survey of AF patients in a city of Japan. Follow-up data were available in 4,472 patients, and hypertensive patients who received prescription of any antihypertensive agents and whose systolic blood pressure was treated to less than 130 mmHg were available were examined (n=1,319). We divided the patients into four groups according to their DBP at baseline; G1 (DBP&lt;60 mmHg, n=349), G2 (60≤DBP&lt;70, n=434), G3 (70≤DBP&lt;80, n=386) and G4 (80≤DBP, n=150), and compared the clinical background and outcomes among groups.

Results

The proportion of female was grater in G1 group, and the patients in G1 group were older. During the median follow-up of 2,458 days, in Kaplan-Meier analysis, the incidence rates of cardiovascular events (composite of cardiac death, ischemic stroke, systemic embolism, non-fatal myocardial infarction and heart failure hospitalization during follow up) were the highest in G1 group and the lowest in G3 group (G1: 7.2% per person-year vs. G2: 4.9% vs. G3: 2.2% vs. G4: 4.4%; p&lt;0.01). Multivariate Cox proportional hazards regression analysis revealed that DBP was an independent determinant of cardiovascular events (G1 vs. G3; hazard ratio (HR): 1.96, 95% confidence intervals (CI): 1.39–2.76, G2 vs. G3; HR: 1.79, 95% CI: 1.28–2.50, G4 vs. G3; HR: 1.56, 95% CI: 0.99–2.45) (Figure 1). When we examined the association of DBP according to 10 mmHg increment, patients with excessively low DBP (&lt;50 mmHg) had significantly higher incidence of cardiovascular events than patients with DBP of 70–79 mmHg (HR: 2.80, 95% CI: 1.81–4.33), and DBP exhibited J curve association with higher incidence of cardiovascular events (Figure 2).

Conclusion

In Japanese AF patients whose systolic blood pressure was treated to less than 130 mmHg, patients with excessively low DBP had significantly higher incidence of cardiovascular events, and DBP exhibited J curve association with higher incidence of cardiovascular events.

Funding Acknowledgement

Type of funding sources: None.

Association of the degree of thrombocytopenia with cause of death in patients with atrial fibrillation: the Fushimi AF Registry

Background

Thrombocytopenia is sometimes found in routine blood tests and is associated with an increased risk of mortality in general population. We have previously reported that atrial fibrillation (AF) patients with thrombocytopenia have a higher mortality than those without thrombocytopenia. However, association of the degree of thrombocytopenia with cause of death in AF patients is unknown.

Purpose

We aimed to investigate the association of baseline platelet count with cause of death including cardiac death, intracranial death, malignancy, infection, extracranial bleeding death, renal failure death, respiratory failure death and undetermined death.

Methods

The Fushimi AF Registry was designed to enroll all of the AF patients in Fushimi-ku, Kyoto. Fushimi-ku is densely populated with a total population of 283,000 and is assumed to represent a typical urban community in Japan. We started to enroll patients from March 2011, and follow-up data with baseline platelet counts less than 150,000/μL were available in 853 patients by the end of September 2020. We divided them into 3 groups according to baseline platelet level: Mild thrombocytopenia (100,000–149,999/μL, n=703), Moderate thrombocytopenia (50,000–99,999/μL, n=120), and Severe thrombocytopenia (&lt;50,000/μL, n=30).

Results

In the entire cohort, the mean age was 76 years, 34% were women, the mean body weight and body mass index was 59.3 kg and 22.9 kg/m2, and the median platelet count were 121,000/μL (interquartile range 109,000 to 141,000/μL). Compared to Mild thrombocytopenia, patients with Moderate or Severe thrombocytopenia were more likely to have chronic kidney disease (42.2% vs 54.2% vs 73.3%, p=0.0003), have higher HAS-BLED score (1.90 vs 2.14 vs 2.00, p=0.047) and lower hemoglobin (12.8g/dL vs 11.7g/dL vs 11.2g/dL, p&lt;0.0001) and were less often prescribed anti platelet drugs. Age, sex, body weight, systolic blood pressure, previous stroke, previous major bleeding, hypertension, diabetes mellitus, CHADS2 score and CHA2DS2-VASc score were comparable between three groups. During the median follow-up period, the incidence rate (per 100 person-years) of all-cause death was 6.82 vs 15.27 vs 9.64. (p&lt;0.001) On univariate analysis, the incidence of all-cause death was higher in Moderate group than Mild group. (HR: 2.15; 95% CI 1.61–2.87, p&lt;0.0001), but there was no significant difference between Mild and Severe groups. (HR: 1.44; 95% CI 0.78–2.64, p=0.243). The incidence of cardiac death was comparable between three groups. (Mild vs Moderate: HR 0.65; 95% CI 0.15–2.75, p=0.56, Mild vs Severe: HR 1.11; 95% CI 0.15–8.23, p=0.92) Regarding other causes of death such as intracranial bleeding, extracranial bleeding, malignancy, infection, renal failure, respiratory failure and undetermined cause, there was no significant difference.

Conclusion

Mortality was higher according to the degree of thrombocytopenia in AF patients, but the cause of death was not different among three groups.

Funding Acknowledgement

Type of funding sources: None.

Predictors and risk model for heart failure hospitalization in atrial fibrillation patients without pre-existing heart failure: the Fushimi AF Registry

Background

Atrial fibrillation (AF) increases the risk of hospitalization for heart failure (HF), as well as that of thromboembolism. The strategy for prediction of thromboembolism has been well-established; however, little focus has been placed on the risk stratification for and prevention of HF hospitalization in AF patients.

Purpose

The aim of this study is to investigate the predictors and risk model of HF hospitalization in non-valvular AF patients without pre-existing HF.

Methods

The Fushimi AF Registry is a community-based prospective survey of AF patients in Fushimi-ku, Kyoto, Japan. The inclusion criterion of the registry is the documentation of AF at 12-lead electrocardiogram or Holter monitoring at any time, and there are no exclusion criteria. We started to enroll patients from March 2011, and follow-up data were available for 4,472 patients by the end of October 2020. From the registry, we excluded patients without a pre-existing HF (defined as having one of the following; prior hospitalization for HF, New York Heart Association class ≥2, or left ventricular ejection fraction [LVEF] &lt;40%), and those with valvular AF (mitral stenosis or prosthetic heart valve). Among 3,188 non-valvular AF patients without pre-existing HF, we explored the risk factors for the HF hospitalization during follow-up period. The risk model for predicting HF hospitalization was determined by the cumulative numbers of risk factors which were significant on multivariate analysis.

Results

The mean age was 72.4±10.8 years, 1197 were female and 1787 were paroxysmal AF. The mean CHADS2 and CHA2DS2-VASc scores were 1.7±1.2 and 2.9±1.6, respectively. During the median follow-up period of 5.1 years, HF hospitalization occurred in 285 (8.9%), corresponding to an annual incidence of 1.8 events per 100 person-years. In multivariable Cox regression analysis, advanced age (≥75 years), valvular heart disease, coronary artery disease, reduced LVEF (&lt;60%), chronic obstructive pulmonary disease (COPD) and anemia were independently associated with the higher incidence of HF hospitalization (all P&lt;0.001) (Picture 1). A risk model based on these 6 variables could stratify the incidence of HF hospitalization during follow-up period (log-rank; P&lt;0.001) (Picture 2). Patients with ≥3 risk factors had an 11-fold higher incidence of HF hospitalization compared with those not having any of these risk factors (hazard ratio: 11.3, 95% confidence interval: 7.0–18.4; P&lt;0.001).

Conclusions

Advanced age, coronary artery disease, valvular heart disease, reduced LVEF, COPD and anemia were independently associated with the risk of HF hospitalization in AF patients without pre-existing HF. There was good prediction for endpoint of HF hospitalization using these 6 variables, providing the opportunities for the implementation of strategies to reduce the incidence of HF among AF patients.

Funding Acknowledgement

Type of funding sources: None.

Characteristics and clinical outcomes in atrial fibrillation patients classified using cluster analysis: the Fushimi AF Registry

AIMS

The risk of adverse events in atrial fibrillation (AF) patients was commonly stratified by risk factors or clinical risk scores. Risk factors often do not occur in isolation and are often found in multimorbidity 'clusters' which may have prognostic implications. We aimed to perform cluster analysis in a cohort of AF patients and to assess the outcomes and prognostic implications of the identified comorbidity cluster phenotypes.

METHODS AND RESULTS

The Fushimi AF Registry is a community-based prospective survey of the AF patients in Fushimi-ku, Kyoto, Japan. Hierarchical cluster analysis was performed on 4304 patients (mean age: 73.6 years, female; 40.3%, mean CHA2DS2-VASc score 3.37 ± 1.69), using 42 baseline clinical characteristics. On hierarchical cluster analysis, AF patients could be categorized into six statistically driven comorbidity clusters: (i) younger ages (mean age: 48.3 years) with low prevalence of risk factors and comorbidities (n = 209); (ii) elderly (mean age: 74.0 years) with low prevalence of risk factors and comorbidities (n = 1301); (iii) those with high prevalence of atherosclerotic risk factors, but without atherosclerotic disease (n = 1411); (iv) those with atherosclerotic comorbidities (n = 440); (v) those with history of any-cause stroke (n = 681); and (vi) the very elderly (mean age: 83.4 years) (n = 262). Rates of all-cause mortality and major adverse cardiovascular or neurological events can be stratified by these six identified clusters (log-rank test; P < 0.001 and P < 0.001, respectively).

CONCLUSIONS

We identified six clinically relevant phenotypes of AF patients on cluster analysis. These phenotypes can be associated with various types of comorbidities and associated with the incidence of clinical outcomes.

CLINICAL TRIAL REGISTRATION INFORMATION

https://www.umin.ac.jp/ctr/index.htm. Unique identifier: UMIN000005834.

Long-term clinical outcomes after major bleeding in patients with atrial fibrillation: the Fushimi AF registry

AIMS

Oral anticoagulants reduce the risk of ischaemic stroke but may increase the risk of major bleeding in atrial fibrillation (AF) patients. Little is known about the clinical outcomes of patients after a major bleeding event. This study assessed the outcomes of AF patients after major bleeding.

METHODS AND RESULTS

The Fushimi AF Registry is a community-based prospective survey of the AF patients in Fushimi-ku, Kyoto, Japan. Analyses were performed on 4304 AF patients registered by 81 institutions participating in the Fushimi AF Registry. We investigated the demographics and outcomes of AF patients who experienced major bleeding during follow-up period. During the median follow-up of 1307 days, major bleeding occurred in 297 patients (6.9%). Patients with major bleeding were older than those without (75.6 vs. 73.4 years; P < 0.01). They were more likely to have pre-existing heart failure (33.7% vs. 26.7%; P < 0.01), history of major bleeding (7.7% vs. 4.0%; P < 0.01), and higher mean HAS-BLED score (2.05 vs.1.73; P < 0.01). On landmark analysis, ischaemic stroke or systemic embolism occurred in 17 patients (3.6/100 person-years) after major bleeding and 227 patients (1.7/100 person-years) without major bleeding, with an adjusted hazard ratio (HR) of 1.93 [95% confidence interval (CI), 1.06-3.23; P = 0.03]. All-cause mortality occurred in 97 patients with major bleeding (20.0/100 person-years) and 709 (5.1/100 person-years) patients without major bleeding [HR 2.73 (95% CI, 2.16-3.41; P < 0.01)].

CONCLUSION

In this community-based cohort, major bleeding is associated with increased risk of subsequent all-cause mortality and thromboembolism in the long-term amongst AF patients.

TRIAL REGISTRATION

https://www.umin.ac.jp/ctr/index.htm. Unique identifier: UMIN000005834. (last accessed 22 October 2020).

Iatrogenic ventricular fibrillation caused by inappropriately synchronized cardioversion in a patient with pre-excited atrial fibrillation: A case report

Direct-current (DC) cardioversion is effective at terminating arrhythmias in an emergency. During treatment, energy delivery synchronizing with the QRS complex is essential to avoid ventricular fibrillation (VF) caused by a shock on the T wave, which is the vulnerable period of ventricular repolarization. However, distinguishing the QRS from the T wave is difficult in some patients with abnormal, irregular, and varying QRS complexes. We report the case of a 45-year-old man who had iatrogenic VF caused by inappropriate synchronization with the T wave during cardioversion of pre-excited atrial fibrillation due to high ventricular rates and varying R wave amplitude affected by an accessory pathway. <Learning objective: During direct-current cardioversion, energy delivery synchronizing with the QRS complex is essential to avoid ventricular fibrillation (VF) caused by a shock on the T wave. However, distinguishing the QRS from the T wave is difficult in some patients with abnormal, irregular, and varying QRS complexes. We report a case of iatrogenic VF caused by failed synchronization with the R wave in a patient with pre-excited atrial fibrillation (AF). Clinicians managing pre-excited AF should be aware of the possibility of iatrogenic VF triggered by cardioversion.>.

Clinical outcomes of Japanese atrial fibrillation patients with combined valvular heart disease: the Fushimi AF Registry

Background

We previously reported that valvular heart disease (VHD) was not at the significant risk of stroke/systemic embolism (SE), but was associated with an increased risk of hospitalization for heart failure (HF) in Japanese atrial fibrillation patients. However, the impact of combined VHD on clinical outcomes has been little known.

Purpose

The aim of this study is to investigate the prevalence of combined VHD and its clinical characteristics and impact on outcomes such as stroke/SE, all-cause death, cardiac death and hospitalization for HF.

Method

The Fushimi AF Registry is a community-based prospective survey of AF patients in one of the wards of our city which is a typical urban district of Japan. We started to enroll patients from March 2011, and follow-up data were available for 4,466 patients by the end of November 2019. In the entire cohort, echocardiography data were available for 3,574 patients. 68 AF patients with prosthetic heart valves were excluded and we compared clinical characteristics and outcomes between 488 single VHD (103 Aortic valve disease (AVD), 315 mitral valve disease (MVD), 70 tricuspid valve disease (TVD)) and 158 combined VHD (46 AVD and MVD, 11 AVD and TVD, 66 MVD and TVD, 35 AVD and MVD and TVD).

Result

Compared with single VHD, patients with combined VHD were older (combined vs. single VHD: 78.5 vs. 76.0 years, respectively; p&lt;0.01), more likely to have persistent/permanent type AF (73.4% vs. 63.9%, p=0.02) and prescription of warfarin (63.1% vs. 53.8%, p=0.04). Combined VHD was less likely to have diabetes mellitus (13.9% vs. 23.6%, p=0.01) and dyslipidemia (26.6% vs. 40.4%, p&lt;0.01). Sex, body weight, hypertension, pre-existing HF were comparable between the two groups.

During the median follow-up of 1,474 days, the incidence rate of stroke/SE was not significantly different between the two groups (1.58 vs. 1.89 per 100 person-years, respectively, log rank p=0.10). The incidence rate of all-cause death (7.35 vs. 5.33, p=0.65), cardiac death (1.20 vs. 0.99, p=0.91) and hospitalization for HF (5.55 vs. 4.43, p=0.53) were also not significantly different. We previously reported AVD had significant impacts on cardiac adverse outcomes in AF patients, and we further analyzed event rates between combined VHD including AVD (AVD and MVD/TVD) and without AVD (MVD and TVD). Combined VHD with AVD group had higher incidence rate of all-cause death (10.7 vs. 5.79, p=0.03) than that without AVD group. However, the incidence rate of stroke/SE (1.98 vs. 1.56, p=0.59), cardiac death (0.98 vs. 1.14, p=0.68), hospitalization for HF (8.03 vs. 5.38, p=0.17) were not significantly different between the two groups.

Conclusion

As compared with single VHD, the risk of stroke/SE, all-cause death, cardiac death and hospitalization for HF in combined VHD was not significantly different. Among patients with combined VHD, those having AVD had higher incidence rate of all-cause death than those without AVD.

Figure 1

Funding Acknowledgement

Type of funding source: None

Plasma natriuretic peptide level is an independent determinant of major clinical outcomes in atrial fibrillation patients without heart failure: the Fushimi AF Registry

Background

Atrial fibrillation (AF) increases the risk of death, stroke/systemic embolism and heart failure (HF). Plasma natriuretic peptide (NP) level is an important prognostic marker in HF patients. However, little is known regarding the prognostic significance of plasma NP level in AF patients without HF.

Purpose

The aim of this study is to investigate the relationship between plasma NP level and clinical outcomes such as all-cause death, stroke/systemic embolism and HF hospitalization during follow-up period in AF patients without HF.

Methods

The Fushimi AF Registry is a community-based prospective survey of AF patients in our city. The inclusion criterion of the registry is the documentation of AF at 12-lead electrocardiogram or Holter monitoring at any time, and there are no exclusion criteria. We started to enroll patients from March 2011, and follow-up data were available for 4,466 patients by the end of November 2019. From the registry, we excluded 1,220 patients without a pre-existing HF (defined as having one of the following; prior hospitalization for HF, New York Heart Association class ≥2, or left ventricular ejection fraction &lt;40%). Among 3,246 AF patients without HF, we investigated 1,189 patients with the data of plasma BNP (n=401) or N-terminal pro-BNP (n=788) level at the enrollment. We divided the patients according to the quartile of each plasma BNP or NT-pro BNP level and compared the backgrounds and outcomes between these 4 groups stratified by plasma NP level.

Results

Of 1,189 patients, the mean age was 72.1±10.2 years, 454 (38%) were female and 684 (58%) were paroxysmal AF. The mean CHADS2 and CHA2DS2-VASc score were 1.6±1.1 and 2.9±1.5, respectively. Oral anticoagulants were prescribed in 671 (56%) at baseline. The median (interquartile range) BNP and N-terminal pro-BNP level were 84 (38, 176) and 500 (155, 984) pg/ml, respectively. Patients with high plasma NP level were older, and demonstrated lower prevalence of paroxysmal AF, higher CHADS2 and CHA2DS2-VASc scores and higher prevalence of chronic kidney disease and oral anticoagulants prescription (all P&lt;0.01). A total of 165 all-cause death, 114 stroke/systemic embolism and 103 HF hospitalization occurred during the median follow-up period of 5.0 years. Kaplan-Meier curves demonstrated that higher plasma NP level was significantly associated with the incidences of all-cause death, stroke/systemic embolism and HF hospitalization in AF patients without HF (Figure 1A). Multivariable Cox regression analysis revealed that plasma NP level could stratify the risk of clinical outcomes even after adjustment by type of AF, CHA2DS2-VASc score, chronic kidney disease and oral anticoagulant prescription (Figure 1B).

Conclusion

Plasma NP level is a significant prognostic marker for all-cause death, stroke/systemic embolism and HF hospitalization in AF patients without HF, suggesting the importance of measuring plasma NP level in AF patients even without HF.

Figure 1

Funding Acknowledgement

Type of funding source: None

Cardiovascular Events and Mortality in Patients With Atrial Fibrillation and Anemia (from the Fushimi AF Registry)

Data regarding the associations of anemia (hemoglobin level <13.0 g/dl in men and <12.0 g/dl in women) with clinical outcomes in patients with atrial fibrillation (AF) remains scarce. This study sought to investigate the associations of anemia with the incidences of stroke or systemic embolism, major bleeding, heart failure (HF) hospitalization, and all-cause mortality including its causes, using the data from a Japanese community-based survey, the Fushimi AF Registry. A total of 4,169 AF patients were divided into the 3 groups, based on the baseline hemoglobin level: no (n = 2,622), mild (11.0 to <13.0 g/dl for men and <12.0 g/dl for women; n = 880), and moderate/severe anemia (<11.0 g/dl; n = 667). During a median follow-up of 1,464 days, the incidences of major bleeding, HF hospitalization, and mortality increased with higher rates of cardiac death, in accordance with anemic severity. On multivariate analyses, the higher risk of moderate/severe anemia, relative to no anemia, for major bleeding remained statistically significant (hazard ratio [HR]: 2.00, 95% confidential interval [CI]: 1.48 to 2.72). The risks of those with anemia, relative to no anemia, for HF hospitalization (mild; HR: 1.87, 95% CI: 1.51 to 2.31, and moderate/severe; HR: 2.02, 95% CI: 1.59 to 2.57) as well as for mortality (mild; HR: 1.80, 95% CI: 1.50 to 2.16, and moderate/severe; HR: 2.95, 95% CI: 2.45 to 3.55) were also higher, but not for stroke/systemic embolism. These relations were consistent, regardless of the use of oral anticoagulants. In conclusion, anemia was associated with higher risks of HF hospitalization, mortality, and major bleeding in AF patients.

Impact of Valvular Heart Disease on Mortality, Thromboembolic and Cardiac Events in Japanese Patients With Atrial Fibrillation - The Fushimi AF Registry

BACKGROUND

There is a growing burden of valvular heart disease (VHD) and atrial fibrillation (AF) due to population aging, but data regarding the characteristics and outcomes of patients with AF and concomitant VHD are lacking.Methods and Results:The Fushimi AF Registry is a community-based prospective survey of AF patients in Fushimi-ku, Kyoto. Among 3,566 patients with available echocardiographic data, 20% had VHD, consisting of 131 valvular AF (VAF: 3.7%) and 583 nonvalvular AF with VHD (NVAF-VHD: 16.3%). Here, VAF was defined as AF with mitral stenosis or a prosthetic heart valve. AF patients with VHD were older, had more comorbidities with a higher CHADS₂ score, and were prescribed oral anticoagulants more frequently than those without VHD. After adjusting for confounders, VHD was not associated with stroke or systemic embolism, all-cause mortality, or cardiac death. NVAF-VHD was significantly associated with an increased risk of hospitalization for heart failure (adjusted hazard ratio [HR], 1.44; 95% confidence interval [CI], 1.16-1.78), whereas VAF was not (HR, 1.28; 95% CI, 0.86-1.92). Among all types of VHD, aortic valve diseases were associated with a higher risk of cardiac events, whereas mitral valve diseases were not.

CONCLUSIONS

Although VHD did not significantly affect thromboembolism or mortality, it affected cardiac events depending on type, with aortic valve diseases having higher risk, in Japanese patients with AF.

PRDM14 promotes malignant phenotype and correlates with poor prognosis in colorectal cancer

BACKGROUND

Emerging evidence suggests that stemness in cancer cells is a cause of drug resistance or metastasis and is an important therapeutic target. PR [positive regulatory domain I-binding factor 1 (PRDI-BF1) and retinoblastoma protein-interacting zinc finger gene (RIZ1)] domain containing 14 (PRDM14), that regulates pluripotency in primordial germ cell, has reported the overexpression and function of stemness in various malignancies, suggesting it as the possible therapeutic target. However, to our knowledge, there have been no reports on the expression and function of PRDM14 in colorectal cancer (CRC). Therefore, we investigated the expression and the role of PRDM14 in CRC.

METHODS

We performed immunohistochemistry evaluations and assessed PRDM14 expression on 414 primary CRC specimens. Colon cancer cell lines were subjected to functional and stemness assays in vitro and in vivo.

RESULTS

We found that PRDM14 positive staining exhibited heterogeneity in the CRC primary tumor, especially at the tumor invasion front. The aberrant expression of PRDM14 at the invasion front was associated with lymph node metastasis and disease stage in patients with CRC. Furthermore, the multivariate analysis revealed high PRDM14 expression as an independent prognostic factor in the patients with Stage III CRC. Overexpression of PRDM14 enhanced the invasive, drug-resistant and stem-like properties in colon cancer cells in vitro and tumorigenicity in vivo.

CONCLUSION

Our findings suggest that PRDM14 is involved in progression and chemoresistance of CRC, and is a potential prognostic biomarker and therapeutic target in the CRC patients.

P3771Validation of risk scoring system predicting for progression of atrial fibrillation: the Fushimi AF Registry

Background

Atrial fibrillation (AF) increases the risks of thromboembolism and death. Progression from paroxysmal to sustained types (persistent or permanent) of AF is sometimes seen in clinical practice. We recently reported that progression of AF was associated with increased risk of clinical adverse events in Japanese AF patients. However, risk stratification schemes of predicting the progression of AF has not been fully established.

Methods

The Fushimi AF Registry, a community-based prospective survey, was designed to enroll all of the AF patients in Fushimi-ku, Kyoto, which is a typical urban district of Japan with a population of 283,000. Follow-up data were available for 4,454 patients. We investigated the risk factors of AF progression and validated the performance of various risk scoring systems predicting for progression of AF, such as APPLE, BASE-AF2, HATCH, and MB-LATER score, using data from 995 paroxysmal AF patients (mean age; 72.6±11.4 years, female; 42.2%, mean CHA2DS2-VASc score; 3.26±1.67) whose echocardiogram data were obtained at baseline.

Results

Of 995 AF patients, during the median follow-up of 1,477 days, progression from paroxysmal to sustained AF occurred in 160 patients (16.1%; 4.0 per 100 person-years). On a multivariate model, we indicated that history of AF ≥2 years (odds ratio [OR] 1.83; 95% confidence interval [CI] 1.28–2.61), left atrial diameter ≥40 mm (OR 1.45; 95% CI 1.02–2.08), daily drinker (OR 1.56; 95% CI 1.24–2.81), and cardiomyopathy (OR 2.58; 95% CI 1.17–5.69) were significantly associated with higher incidence of AF progression. Our model had better predictive potential for AF progression (area under curve [AUC] 0.612; 95% CI 0.566–0.658) than the APPLE (AUC 0.553; 95% CI 0.508–0.598; p=0.06), BASE-AF2 (AUC 0.571; 95% CI 0.526–0.617; p=0.04), CHADS2 (AUC 0.508; 95% CI 0.462–0.554; p<0.01), CHA2DS2-VASc (AUC 0.501; 95% CI 0.453–0.548; p<0.01), HATCH (AUC 0.502; 95% CI 0.456–0.548; p<0.01), and MB-LATER (AUC 0.528; 95% CI 0.483–0.572; p<0.01) score.

Conclusion

We identified 4 risk factors which may be useful to predict for progression of AF in Japanese patients. External validation of our model in other cohorts is needed.

Acknowledgement/Funding

Boehringer, Bayer, Pfizer, Bristol-Myers, Astellas, AstraZeneca, Daiichi Sankyo, Novartis, MSD, Sanofi and Takeda. Japan Agency for Medical Research

P3780Clinical characteristics and outcomes in Japanese atrial fibrillation patients with valvular heart disease: the Fushimi AF registry

Background

Previous studies have suggested that valvular atrial fibrillation (VAF), defined as atrial fibrillation (AF) patients with prosthetic valve or rheumatic mitral stenosis, increased the risks of thromboembolism. However, clinical characteristics and outcomes of VAF and non-valvular AF (NVAF) patients with other valvular heart disease (VHD) has not been fully described.

Method

The Fushimi AF Registry was designed to enroll all of the AF patients. In the entire cohort (4,454 patients), follow-up data including echocardiography data were available for 3,566 patients. We compared clinical characteristics and outcomes between 131 VAF patients (3.7%), 583 NVAF with VHD (NVAF-VHD: 16.3%) and 2,852 without VHD (Non-VHD: 80.0%).

Result

Compared with Non-VHD, patients in VAF and NVAF-VHD were older (VAF vs. NVAF-VHD vs. Non-VHD: 74.3 vs. 76.9 vs. 72.9 years, respectively; p≤0.0001), more often female (56.5% vs. 51.1% vs. 36.9%, p≤0.0001), less in body weight (54.3 vs. 54.7 vs. 60.6 kg, p≤0.0001), more persistent/permanent type (64.1% vs. 65.4% vs. 45.8%, p≤0.0001), more likely to have heart failure (61.8% vs. 53.2% vs. 23.3%, p≤0.0001), had higher CHADS2 score (2.18 vs. 2.49 vs. 1.96, p≤0.0001) and CHA2DS2-VASc score (3.71 vs. 4.02 vs. 3.26, p≤0.0001), and received oral anticoagulant prescription more frequently (78.6% vs. 63.0% vs. 55.6%, p0.0001). NVAF-VHD was more likely to have previous stroke/systemic embolism (SE) than VHD or Non-VHD (14.5% vs. 23.5% vs. 19.6%, p=0.03). VAF or NVAF-VHD had larger left atrium than Non-VHD (50.5 vs. 47.2 vs. 42.4 mm, p<0.0001). Heart rate, diabetes mellitus and previous bleeding were comparable between the groups.

During the median follow-up of 1,471 days, the incidence rate of stroke/SE was not significantly different between three groups, however, NVAF-VHD showed modestly higher rate than Non-VHD (1.67 vs. 1.96 vs. 1.28 per 100 person-years, respectively, log rank p=0.054) (Figure). The incidence rates of all-cause death (4.62 vs. 5.74 vs. 3.21, p≤0.0001), cardiac death (1.07 vs. 1.01 vs. 0.44, p=0.0003), and those of hospitalization for heart failure (3.29 vs. 4.41 vs. 1.80, p≤0.0001) were higher in NVAF-VHD and VAF, than Non-VHD. After adjustment by relevant factors including the components of CHA2DS2-VASc score and oral anticoagulant use, NVAF-VHD, but not VAF, was an independent predictor for hospitalization for heart failure. Neither VAF nor NVAF-VHD was predictors for all-cause death, cardiac death or stroke/SE.

Figure 1. Incidence of stroke/SE

Conclusion

As compared with Non-VHD, the risk of stroke/SE in VAF and NVAF-VHD was not particularly high; although NVAF-VHD had modestly higher rate than Non-VHD. VAF and NVAF-VHD were associated with higher incidence rates of all-cause death, cardiac death and hospitalization for heart failure. NVAF-VHD was an independent predictor for hospitalization for heart failure in multivariate analysis.

Acknowledgement/Funding

Pfizer, Bristol-Myers Squibb, Boehringer Ingelheim, Bayer Healthcare and Daiichi Sankyo

P5663Impact of proteinuria on cardiovascular outcomes in Japanese diabetic patients with atrial fibrillation: the Fushimi AF Registry

Background

Previous studies have suggested that proteinuria is independently associated with clinical outcomes in diabetic patients, irrespective of the presence of renal dysfunction. However, data regarding the impact of proteinuria on clinical outcomes in diabetic patients with atrial fibrillation (AF) are limited.

Methods

The Fushimi AF Registry is a community-based prospective survey of AF patients in our city in Japan. Follow-up data were available in 4,454 patients, and 634 diabetic patients with available data of proteinuria and estimated glomerular filtration rate (eGFR) were examined. We compared the clinical background and outcomes between patients with proteinuria (n=251) and those without (n=383). Then, we divided the patients into 4 subgroups according to the presence of proteinuria and renal dysfunction, and compared the clinical outcomes between groups; group 1 (without proteinuria, eGFR ≥60 ml/min/1.73 m2; n=203), group 2 (with proteinuria, eGFR ≥60; n=96), group 3 (without proteinuria, eGFR <60; n=180), group 4 (with proteinuria, eGFR <60; n=155).

Results

Age was comparable between patients with or without proteinuria. Patients with proteinuria had higher prevalences of previous heart failure (HF), stroke/systemic embolism, hypertension and renal dysfunction. The prevalences of previous myocardial infarction, and major bleeding were similar between two groups. During the median follow-up of 1,505 days, the incidence rates of HF hospitalization (4.1/100 person-years vs. 2.5/100 person-years; p<0.01) and cardiovascular death (1.8/100 person-years vs. 0.4/100 person-years; p<0.01) were higher in patients with proteinuria. When we divided patients into 4 subgroups, the incidences of HF hospitalization (group 1: 1.8/100 person-years vs. group 2: 3.4/100 person-years vs. group 3: 3.8/100 person-years vs. group 4: 4.9/100 person-years; p<0.01) and cardiovascular death (group 1: 0.3/100 person-years vs. group 2: 1.8/100 person-years vs. group 3: 0.5/100 person-years vs. group 4: 2.2/100 person-years; p<0.01) tended to be higher in not only group 3 and group 4 but also group 2 than group 1 (Figure). Multivariate Cox proportional hazards regression analysis including female gender, age (≥75 years), hypertension, pre-existing HF, renal dysfunction (eGFR <60),low left ventricular ejection fraction (<40%) and proteinuria revealed that proteinuria was an independent determinant of both of HF hospitalization (adjusted hazard ratio [HR]: 1.57, 95% confidence interval [CI]: 1.05–2.34) and cardiovascular death (HR: 3.76, 95% CI: 1.59–8.88).

Figure 1

Conclusion

In Japanese diabetic patients with AF, proteinuria was associated with higher incidences of HF hospitalization and cardiovascular death, irrespective of the presence of renal dysfunction.

P3758Clinical characteristics and outcomes of atrial fibrillation patients with thrombocytopenia: the Fushimi AF Registry

Background

Thrombocytopenia is sometimes found in routine blood tests and is reported as a risk factor of major bleeding events and incidence of all-cause death after percutaneous coronary intervention. However, the influence of thrombocytopenia on clinical outcomes in patients with atrial fibrillation (AF) remains unknown.

Purpose

We aimed to investigate relationship between baseline platelet count and clinical outcomes such as all-cause death, hospitalization for heart failure, and the major bleeding event in AF patients.

Methods

The Fushimi AF Registry was designed to enroll all of the AF patients in Fushimi-ku, Kyoto. Fushimi-ku is densely populated with a total population of 283,000 and is assumed to represent a typical urban community in Japan. Follow-up data with baseline platelet counts were available in 4,179 patients from March 2011 to November 2018. We divided the entire cohort into 3 groups according to baseline platelet level: No thrombocytopenia (≥150,000/μL, n=3,323), Mild thrombocytopenia (100,000–149,999/μL, n=707), and Moderate/severe thrombocytopenia (≤99,999/μL, n=149).

Results

In the entire cohort, the mean age was 73 years, 40% were women, and the mean body weight and body mass index was 59 kg and 23.1 kg/m2, and the median platelet count were 192,000/μL (interquartile range 156,000 to 232,000/μL), respectively.

Compared to No thrombocytopenia, patients with thrombocytopenia were older (No vs. Mild vs. Moderate/severe; 73.3 years vs. 76.5 years vs. 75.8 years, p<0.0001), more likely to have heart failure (27.0% vs. 32.8% vs. 41.6%, p<0.0001), more likely to have chronic renal disease (35.7% vs. 42.6% vs. 57.7%, p<0.0001), and had higher CHADS2 score (2.05 vs. 2.17 vs. 2.34, p=0.0039) and CHA2DS2-VASc score (3.40 vs. 3.52 vs. 3.71, p=0.0416). Patients with thrombocytopenia had lower hemoglobin (13.0 vs. 12.8 vs. 11.6, p<0.0001) than No thrombocytopenia. However, prevalence of previous major bleeding events was comparable between three groups (4.66% vs. 4.67% vs. 5.37%, p=0.92)

On Kaplan-Meier analysis, the incidence of all-cause death was higher in Mild group (hazard ratio [HR] 1.51; 95% confidence interval [CI] 1.28–1.77) and Moderate/severe group (HR 2.97; 95% CI 2.28–3.80) than No group (Figure 1). The incidence of hospitalization for heart failure was higher in Mild group (HR 1.62; 95% CI 1.31–1.99) and Moderate/severe group (HR 2.64; 95% CI 1.76–3.81) than No group (Figure 2). The incidence of major bleeding event was higher in Mild group (HR 1.46; 95% CI 1.11–1.91) and Moderate/severe group (HR 2.45; 95% CI 1.41–3.91) than No group (Figure 3).

Conclusion

Thrombocytopenia in AF patients was associated with higher incidence of all-cause death, hospitalization for heart failure, and major bleeding event in the Fushimi AF Registry.

Acknowledgement/Funding

Pfizer, Bristol-Myers Squibb, Boehringer Ingelheim, Bayer Healthcare,and Daiichi-Sankyo

A case of pulmonary lymphoproliferative disorder presenting rapidly progressive respiratory failure

A 72-year-old woman presented with acute onset of shortness of breath and fatigue over several days, and was found to be in acute respiratory failure. Computed tomography of the chest revealed diffuse ground-glass opacities, crazy-paving, multiple nodules, and a large mass in the right lower lobe. She was diagnosed with B-cell lymphoma and a pulmonary lymphoproliferative disorder (PLD). PLD is known to present with a variety of radiographic patterns. The course of PLD is usually one of slow progression, and acute respiratory failure is a rare presentation. Physicians should be aware that acute respiratory failure can be caused by PLD.

Spontaneous coronary artery dissection in a woman undergoing pseudomenopause therapy with leuprorelin: A case report

Spontaneous coronary artery dissection (SCAD) is a rare cause of acute coronary syndrome. SCAD frequently affects women, and may be associated with pregnancy and the peripartum period. Therefore, female sex hormones are thought to play a pathogenetic role. Although pseudomenopause therapy may alter female sex hormone levels similar to those during pregnancy, there are no reported cases of SCAD associated with pseudomenopause therapy. We report the case of a 48-year-old woman who developed SCAD while undergoing pseudomenopause therapy with leuprorelin. This case suggests an association between SCAD and pseudomenopause therapy with leuprorelin.

<Learning objective: Spontaneous coronary artery dissection (SCAD) is a rare cause of acute coronary syndrome (ACS). SCAD frequently affects women and is thought to be associated with female sex hormones. Here, we report a case of SCAD in a patient who was undergoing pseudomenopause therapy with leuprorelin to treat uterine fibroids. Young or middle-aged women who present with symptoms suggestive of ACS should be asked about not only pregnancy and menstrual history, but also therapies altering female sex hormones.>

Predictors of therapeutic effect of transarterial chemoembolisation using drug-eluting beads for hepatocellular carcinoma

AIMS

To identify predictors of a therapeutic effect after transarterial chemoembolisation using drug-eluting beads (DEB-TACE) for hepatocellular carcinoma (HCC).

MATERIALS AND METHODS

Between January 2015 and July 2015, tumour variables and angiographic data were collected for 25 patients (49 target lesions) after they had undergone the DEB-TACE procedure for HCC. The therapeutic effect was evaluated according to the Response Evaluation Criteria in Cancer of the Liver at follow-up dynamic computed tomography (CT) performed within 1-4 months after the procedure. A p<0.05 was considered significant.

RESULTS

On a target lesion basis, the objective response (TE3/4) rate was 63.3% (31 of 49). On univariate analysis, larger size (≥2 cm) was a predictor of an objective response (p=0.029). The tumour location of the medial (segment 4) or caudate (segment 1) lobe also indicated a poor therapeutic effect (TE1/2), but not at the level of significance (p=0.051). Multivariate analysis identified tumour size (odds ratio, 8.60; 95% confidence interval, 1.87-62.8) and tumour location (odds ratio, 12.2; 95% confidence interval, 2.12-129.8) as significant factors associated with a therapeutic effect. On a patient basis, 10 of 25 (40%) patients showed complete response/partial response. There were no significant differences between complete response/partial response and stable disease/progressive disease regarding age, gender, tumour markers, history of previous treatment, Child-Pugh class, T-stage, or Barcelona Clinic Liver Cancer Staging.

CONCLUSION

A short-term therapeutic effect was associated with tumour size and location on a target lesion basis.

Diets with no or low amounts of dietary fiber can reduce small intestinal ulcers induced by non-steroidal anti-inflammatory drugs in dogs

Recent progress in endoscopic techniques has revealed that non-steroidal anti-inflammatory drugs (NSAIDs) often cause ulcers in the small intestine in humans, but effective therapy is not available at present. In the present study, we investigated the effects of feeding condition and the amount of dietary fiber (DF) in the diet on the formation of gastrointestinal ulcers induced by NSAIDs in dogs. Several types of diets containing various percentages of DF were given to dogs. Indomethacin (1 or 3 mg/kg, p.o.), ketoprofen (2 mg/kg, s.c.), or fulnixin (1 mg/kg, s.c.) was administered once daily at 10 a.m. after a morning meal or without a morning meal (fasted condition) for 3 - 7 days. Gastrointestinal lesions were examined 24 h after the final dose of the drugs. When indomethacin (3 mg/kg) was administered after a morning meal (fed condition) for 7 days, it produced many lesions in the small intestine. However, when it was given in the fasted condition without the morning meal, the lesions were markedly decreased. All the NSAIDs given after feeding of regular dry food containing 6% DF once a day for 3 days produced many lesions in the small intestine. The lesions were decreased or increased in dogs given prescription diets containing low DF (1.1%) and high DF (15.4%), respectively. Furthermore, lesions were not observed in dogs given canned diet containing very low DF (< 0.1%), whereas lesions appeared again in dogs given canned diet supplemented with cellulose (3 or 10%) but not with pectin (10%). These results suggested that both feeding condition and insoluble DF, such as cellulose in the diet, play an important role in the formation of NSAID-induced small intestinal lesions, and that a diet with no or low amounts of DF may decrease gastrointestinal side-effects associated with the use of NSAIDs.

Fatty change in moderately and poorly differentiated hepatocellular carcinoma on MRI: a possible mechanism related to decreased arterial flow

AIM

To clarify the frequency of fatty change in moderately and poorly differentiated hepatocellular carcinomas (mHCCs and pHCCs) and its relationship to arterial blood flow.

MATERIALS AND METHODS

One hundred and thirty-six surgically resected HCC lesions were studied. All patients had undergone dynamic magnetic resonance imaging (MRI) with chemical-shift-encoded water-fat imaging (CSI). The presence of fat was identified by a signal drop-off on CSI and confirmed at pathology. Lesions were classified into four groups in the arterial phase; G1, hypointense; G2, isointense; G3, slightly and heterogeneously hyperintense; G4, markedly and homogeneously hyperintense. The number of cumulative arteries (CAs) in the tumours in the pathology examination were counted.

RESULTS

A fat component was observed significantly more frequently in the pHCCs (13/21; 61.9%) compared to the mHCCs (32/101; 31.7%; p=0.013). The numbers of lesions in each group were as follows: (G1, G2, G3, G4) = (18, 9, 23, 4) in the HCCs with fat; (1, 6, 24, 51) in the HCCs without fat (p<0.001); (5, 5, 18, 4) in the mHCCs with fat; (0, 3, 19, 47) in the mHCCs without fat (p<0.001); (11, 0, 2, 0) in the pHCCs with fat; (0, 2, 3, 3) in the pHCCs without fat (p=0.001). The number of CAs in the fat-containing HCCs (5.5±2.9) was significantly lower than that in the HCCs without fat (10.8±5.3; p<0.001).

CONCLUSION

A fat component was more commonly observed in the pHCCs than in the mHCCs. The present results showed a possible mechanism of fatty change in mHCCs and pHCCs in relation to decreased arterial blood supply.

Endocardial Invasion of Lung Cancer Undiagnosable before Autopsy

A 59-year-old male patient presented with left chest discomfort on admission. His medical history included encephalitis in childhood and his smoking history was 20 cigarettes per day for 40 years. A physical examination showed an anemic and edematous face with weak respiratory sounds in the left lung. The patient had elevated calcium levels and decreased hemoglobin and potassium. His parathyroid hormone-related protein level was elevated. Thoracic radiography showed cardiomegaly and computed tomography revealed a left lung mass with invasion of the heart and pleural effusion. Magnetic resonance imaging showed endocardial invasion of the tumor mass. Gallium-68 imaging revealed positive accumulation in the region surrounding the heart. No diagnoses were possible upon frequent cytology of his sputum and pleural effusion. The patient died from congestive heart failure with anoxia 38 days after admission. An autopsy revealed tumoral mass occlusion in the left main bronchus and tumoral invasion of the left atrium, left ventricle, and aorta.

Spontaneous remission of epstein-barr virus-positive diffuse large B-cell lymphoma of the elderly

A 94-year-old female patient presented with anorexia and left axillar lymphadenopathy on admission. Her past history was angina pectoris at 83 years of age and total gastrectomy due to gastric cancer at 87 years. The family history revealed that her son had had a malignant lymphoma, the histopathological diagnosis of which was diffuse large B-cell lymphoma. A physical examination showed both cervical, axillar, and inguinal lymphadenopathy without tenderness. She had elevated lactate dehydrogenase, ferritin, and soluble interleukin-2 receptor (sIL-2R). Whole-body computed tomography confirmed the cervical, axillary, and inguinal lymphadenopathy. Gallium-68 imaging revealed positive accumulation in these superficial lymph nodes. A right inguinal lymph node biopsy showed features of Epstein-Barr virus-associated lymphoproliferative disorder. Immunohistological studies on this lymph node biopsy showed CD20-positive large cells, CD3-positive small cells, and CD30-partly-positive large cells. In situ hybridization showed Epstein-Barr virus-positive, LMP-partly-positive, and EBNA2-negative cells. She refused chemotherapy as her son had died from hematemesis during chemotherapy. She received intravenous hyperalimentation for 1 month after admission. No palpable lymph nodes were identified by physical examination or computed tomography 3 months after admission, and regression of lactate dehydrogenase, ferritin, and sIL-2R was observed. She recovered from anorexia and was discharged. She died from pneumonia 10 months later after initial symptoms of anorexia. The autopsy showed no superficial lymphadenopathy.

Hepatic falciform ligament artery in patients with chronic liver diseases: detection on computed tomography hepatic arteriography

BACKGROUND

The detection rate of hepatic falciform ligament artery (FLA) has been reported as ranging from 2-25%. The rate of FLA on laparotomy, however, is reported to be higher, at 68%.

PURPOSE

To compare the detection rate of FLA on computed tomography hepatic arteriography (CTHA) with that on angiography and dynamic CT, and to clarify the clinical significance of FLA in patients with chronic liver disease.

MATERIAL AND METHODS

126 consecutive patients underwent CTHA angiography and dynamic CT to evaluate suspected liver tumors. Liver function was classified as follows: normal, n=5; Child-Pugh class A, n=94; B, n=21; and C, n=6. All CT images were obtained using multidetector (MDCT) scanners (Aquilion; Toshiba, Tokyo, Japan). For CTHA, CT images were obtained during contrast material injection through the left hepatic, proper, or common hepatic artery. On CT, FLAs were retrospectively identified within the hepatic falciform ligament and the hepatic round ligament by the paging method on a workstation (TWS-5000; Toshiba, Tokyo, Japan). The detection rates were compared among the three modalities (hepatic arterial phase of dynamic CT, CTHA, and angiography). The calibers of FLA were also correlated with the hepatic function of the patients.

RESULTS

The detection rates of FLA by angiography, dynamic CT, and CTHA were 37% (47/126), 10% (13/126), and 77% (97/126), respectively. The calibers of FLA increased as the hepatic function deteriorated (P=0.001).

CONCLUSION

The detection rates of FLA with CTHA are far higher than those with angiography and dynamic CT. Careful interpretation with recognition of FLA on CTHA images is important, as inadvertent embolization or chemotherapeutic infusion of the FLA may result in supraumbilical skin rash.

Microcoil embolization through a downsized coaxial catheter system: an experimental study

BACKGROUND

Most of the recently developed microcatheters for abdominal angiography still have large diameters at their trailing ends, and thus cannot be used for microcoil embolization in combination with a 3-French (F) system.

PURPOSE

To evaluate the in vitro passage of microcoils through a newly developed 2-F microcatheter (Meister Cath Superselective Plus, MC6) that is compatible with a downsized coaxial catheter system (3-F system) in an experimental study.

MATERIAL AND METHODS

We evaluated the passage of microcoils through MC6 within a blood vessel model using the saline flush technique. Six types of microcoils and 17 size variations (maximal curled diameter 2-10 mm, total length 20-140 mm) were used. We evaluated the passage and post-deployment shape of the microcoils as well as the volume of saline required to flush them.

RESULTS

In the experimental study, all microcoils passed through the MC6 and deployed in a satisfactory manner without catheter occlusion. The mean volumes of saline required to flush the TORNADO (n=1), Reverse TORNADO (n=6), HILAL (n=1), Micronester (n=3), VortX (n=4), and C-Stopper Coil (n=2) were 0.7 ml, 0.58+/-0.20 ml, 0.5 ml, 0.57+/-0.058 ml, 3.5+/-1.5 ml, and 0.70+/-0.14 ml, respectively. There was a statistically significant difference in the mean volume of saline required between the VortX and Reverse TORNADO (P=0.029), and between the VortX and C-Stopper Coil (P=0.031). The VortX required the greatest volume of saline.

CONCLUSION

Microcoil embolization through a 3-F system appears to be feasible for the coils examined in this study.

Liver lesions of visceral larva migrans due to Ascaris suum infection:

The purpose of this study was to analyze computed tomographic (CT) findings of hepatic lesions due to Ascaris suum infection. CT of the liver in three patients, all of whom had immunoserologically confirmed A. suum infection, were retrospectively reviewed. Twenty-five lesions were identified in total. Two radiologists analyzed CT findings in a consensus fashion, with particular interest in the margin, shape, and location of the lesions. Hepatic lesions were ill-defined (22 of 25), small (3-35 mm; average, 11 mm), and nodular (18 of 25) or wedge (three of 25) in shape. Most were located in periportal (16 of 25) or subcapsular (six of 25) regions. Hepatic nodules due to visceral larva migrans of A. suum were located mainly in periportal or subcapsular regions, which may represent periportal eosinophilic granuloma, its pathologic feature. The results were considered to represent the pathophysiology of this entity.

Effects of aging on muscle T2 relaxation time: difference between fast- and slow-twitch muscles

RATIONALE AND OBJECTIVES

To determine whether the T2 relaxation time of skeletal muscle is affected by aging and to compare the effects of aging between fast- and slow-twitch muscles in a human study. To investigate the mechanisms of age-related changes in T2 relaxation time in an animal (mouse) study.

METHODS

T2 relaxation times of the soleus (slow-twitch, rich in type I fiber) and gastrocnemius (fast-twitch, rich in type II fiber) muscles were examined in 59 healthy human subjects, 22 to 76 years of age, by clinical magnetic resonance imaging. In mice, T2 relaxation times, fat ratios, and extracellular space ratios (extracellular space/intracellular plus extracellular space) of the spinalis (fast-twitch, rich in type II fiber) muscles were also examined (group of 7 old mice, 24-26 months; group of 7 young mice, 8-10 weeks).

RESULTS

In the human study, the T2 relaxation time of the gastrocnemius muscle increased significantly with aging (r = 0.53, P < 0.01) while that of the soleus muscle did not. In the animal study, the T2 relaxation time of the spinalis muscle was significantly longer (P < 0.05) and the extracellular space ratio of the spinalis muscle significantly wider (P < 0.01) in old than in young mice. No significant difference in fat ratio was observed between old and young mice. A significant, positive correlation was seen between the extracellular space ratio and T2 relaxation time (r = 0.84, P < 0.01).

CONCLUSIONS

The T2 relaxation time of fast-twitch muscle increases with aging, due mainly to increased extracellular space, reflecting age-related type II fiber atrophy.

Radicicol binding to Swo1/Hsp90 and inhibition of growth of specific temperature-sensitive cell cycle mutants of fission yeast

A panel screening using cdc mutants of Schizosaccharomyces pombe identified radicicol as a potent growth inhibitor of certain mutants at the permissive temperature. The strains sensitive to radicicol were cdc7, cdc11, and cdc14, all of which are defective in early septum formation. Cytokinesis but not nuclear division of these mutants was inhibited by radicicol, but that of cells with the wild-type background was not. A biologically active derivative of radicicol with a biotin moiety at the C-11 position bound Swo1, an Hsp90 homologue in S. pombe. Increased Swo1 expression partially suppressed radicicol sensitivity of cdc14 and almost completely rescued morphological abnormalities in cdc14 and cdc7 cells induced by radicicol at the permissive temperature. On the other hand, the increased Swo1 expression did not restore septum formation at the nonpermissive temperature. These results suggest that Swo1, as a molecular chaperone, plays a role in stabilizing these temperature-sensitive proteins at the permissive temperature or in activating the cytokinesis signaling cascade.

Expression of the c-myc and c-fos genes as a potential indicator of late radiation damage to the kidney

PURPOSE

To evaluate proliferative response according to c-myc and c-fos gene expression as an early indicator of late radiation damage to the kidney.

METHODS AND MATERIALS

c-myc and c-fos gene expression was measured in the irradiated kidney of C3H/HeSlc mice using reverse transcriptase-polymerase chain reaction (RT-PCR) 24 h after 9, 12, and 15 Gy as well as 2 and 7 days after 15 Gy. In a second experiment, 12 Gy was administered to the right kidney plus the lower half of left kidney. The mice underwent left nephrectomy 24 h after, and the correlation between increased gene expression and elevation of the blood urea nitrogen (BUN) level representing late functional damage was investigated.

RESULTS

c-myc and c-fos expression increased in 1 of 10 controls and in 8 of 10 and 7 of 10 mice that received 15 Gy, respectively. Expression increased dose-dependently from 9 to 15 Gy. In mice having an increased BUN level, 7 of 10 and 8 of 10 were positive for c-myc and c-fos, respectively. All 6 mice having an unchanged BUN level were negative for c-fos, while 5 were negative for c-myc.

CONCLUSION

Measurement of c-myc and c-fos gene expression is potentially an early indicator of late radiation damage to the kidney.