Left Ventricular Diastolic Dysfunction Is Associated With the Prevalence of Paroxysmal Atrial Fibrillation Determined on the Latest Echocardiographic Criteria

Background: The relationship between left ventricular diastolic dysfunction (LVDD) and paroxysmal atrial fibrillation (PAF) remains unclear because of a lack of standard measures to evaluate LVDD. Accordingly, we examined the association between the prevalence of PAF and each LVDD grade determined according to the latest American Society of Echocardiography guidelines.

Methods and Results: In all, 2,063 patients without persistent AF who underwent echocardiography at Saitama Municipal Hospital from July 2016 to June 2017 were included in the study. Patients were divided into LVDD 6 categories: No-LVDD (n=1,107), Borderline (n=392), Grade 1 (n=204), Indeterminate (n=62), Grade 2 (n=254), and Grade 3 (n=44). PAF was documented in 111 (10.0%), 81 (20.7%), 28 (13.7%), 6 (9.7%), 52 (20.5%), and 24 (54.5%) patients in the No-LVDD, Borderline, Grade 1, Indeterminate, Grade 2, and Grade 3 categories, respectively. PAF prevalence was higher in patients with Grade 3 LVDD across the whole study population. Subgroup analyses showed that the prevalence of PAF increased with increased LVDD grade in patients with reduced left ventricular ejection fraction. This relationship was significant in multivariate analysis including various patient characteristics.

Conclusions: LVDD severity determined on the basis of the latest echocardiographic criteria was associated with the prevalence of PAF. The present findings shed light on the development of new therapeutic markers for PAF.

Practical guidance for echocardiography for cancer therapeutics-related cardiac dysfunction

The prognosis of patients with cancer has improved due to an early diagnosis of cancer and advances in cancer treatment. There are emerging reports on cardiotoxicity in cancer treatment and on cardiovascular disease in cancer patients, from which cardiovascular disease has been recognized as a common cause of death among cancer survivors. This situation has led to the need for a medical system in which oncologists and cardiologists work together to treat patients. With the growing importance of onco-cardiology, the role of echocardiography in cancer care is rapidly expanding, but at present, the practice of echocardiography in clinical settings varies from institution to institution, and is empirical with no established systematic guidance. In view of these circumstances, we thought that brief guidance for clinical application was necessary and have therefore developed this guidance, although evidence in this field is still insufficient.

Cohort profile: patient characteristics and quality-of-life measurements for newly-referred patients with atrial fibrillation-Keio interhospital Cardiovascular Studies-atrial fibrillation (KiCS-AF)

PURPOSE

Besides the high rates of morbidity and mortality, atrial fibrillation (AF) is also associated with impairment of quality-of-life (QOL). However, reports covering non-selected AF population within Asian countries remain scarce. The objective of the Keio interhospital Cardiovascular Studies-atrial fibrillation (KiCS-AF) registry is to clarify the baseline and QOL profiles of the AF patients at the time of initial referral to identify areas for improvement and country-specific gaps.

PARTICIPANTS

The KiCS-AF registry is a multicentre, prospective cohort study designed to specifically recruit AF patients newly referred to the 11 network hospitals within the Kanto area of Japan. The registry completed its enrolment in June 2018. All patients were requested to answer the Atrial Fibrillation Effect on Quality-of-Life (AFEQT) questionnaire both at baseline and 1 year, with planned clinical follow-up for 5 years. The registry also assessed individual treatment strategies including rate and rhythm control, stroke prophylaxis, and their impacts on patient-reported QOL.

FINDINGS TO DATE

As of December 2016, 2464 AF patients were registered; their mean age was 67.1 years (SD, 11.7), majority (69.7%; n=1717) were men and 49.2% presented with paroxysmal AF. The mean CHA₂DS₂-VASc (cardiac failure or dysfunction, hypertension, age ≥75 years, diabetes, stroke including vascular disease, age 65-74 years, and sex category [female]) score was 2.3 (SD, 1.6) and oral anticoagulant therapy was used for 88.6% of patients with CHA₂DS₂-VASc scores ≥2. The median AFEQT-overall summary score was 79.1 (IQR, 66.6-89.1). Roughly 50% had significantly impaired QOL (ie, AFEQT <80) at baseline. Currently, 2307 eligible patients (93.6%) have completed the 1-year follow-up, of which 2072 patients (89.8%) answered the second AFEQT questionnaire.

FUTURE PLANS

The KiCS-AF allowed for extensive investigation of AF-related QOL in a non-selected population with long-term follow-up using a rigorously validated QOL assessment tool. Almost half of patients had impaired QOL at baseline. Further investigations aimed at providing care and improving patient-reported QOL are required.

Assessment of Sex Differences in the Initial Symptom Burden, Applied Treatment Strategy, and Quality of Life in Japanese Patients With Atrial Fibrillation

IMPORTANCE

The clinical characteristics and outcomes of women and men with atrial fibrillation (AF) are reported to be different. However, whether sex-related differences extend to patients' symptom burden and perceived quality of life (QOL) or the management pattern of AF has been rarely studied, particularly in Asian countries.

OBJECTIVE

To assess the differences in symptoms, treatment, and QOL between Japanese female and male patients with AF.

DESIGN, SETTING, AND PARTICIPANTS

Retrospective cohort study using data from the multicenter outpatient registry Keio Interhospital Cardiovascular Studies-Atrial Fibrillation (KiCS-AF), which collects information regarding health status and the treatment of patients with newly diagnosed or referred AF. One-year follow-up data were available for 1534 patients at 11 referral centers in the Tokyo, Japan, area who were enrolled between September 2012 and December 2015. All data available up to the 1-year follow-up examination through July 31, 2017, were included.

MAIN OUTCOMES AND MEASURES

Sex, symptoms, AF treatment, and QOL as determined by Atrial Fibrillation Effect on Quality of Life (AFEQT) questionnaires at their initial visit and 1 year later.

RESULTS

Of 1534 patients, 1076 (70.1%) were men. Compared with men, women were more likely to be older (median age, 73 years [interquartile range {IQR}, 65-78 years] vs 65 years [IQR, 57-73 years], P < .001) and have higher median brain-type natriuretic peptide levels (102.8 pg/mL [IQR, 47.3-235.5 pg/mL] vs 74.1 pg/mL [IQR, 28.5-150.5 pg/mL], P < .001). Women also had lower median AFEQT overall summary scores than men (75 [IQR, 61-85] vs 80 [IQR, 69-90]; P < .001) but similar treatment satisfaction at baseline. During follow-up, women were less likely to be treated with a rhythm control strategy (48.1% [n = 214] vs 58.0% [n = 621], P < .001), including catheter ablation of AF (adjusted hazard ratio, 0.77 [95% CI, 0.62-0.95]; P = .02). At 1-year follow-up, women and men had improved QOL scores, regardless of their baseline characteristics (eg, age or brain-type natriuretic peptide levels) or treatment strategies, yet the sex gap persisted and grew (adjusted change in AFEQT overall summary score during 12 months, 5.89 [95% CI, 2.24-9.54] in women vs 8.94 [95% CI, 5.59-12.30] in men; P = .02).

CONCLUSIONS AND RELEVANCE

In contemporary Japanese clinical practice among unselected patients with AF, women were initially seen with greater QOL impairment, and the sex gap grew 1 year after presentation. The present study underscores the need for focused efforts to better understand and close this observed sex gap over the initial year of treatment for patients with AF.

Practical guidance for the implementation of stress echocardiography

Exercise stress testing has been widely undertaken for the diagnosis of heart diseases. The accurate assessment of clinical conditions can be conducted by comparing the findings obtained from the results of stress echocardiography with the changes in the blood/heart rate and electrocardiograms. Numerous overseas studies have reported the utility of stress echocardiography in diagnosing myocardial ischemia; in Japan, the use of this modality for this purpose was included in the national health insurance reimbursable list in 2012. Nevertheless, stress echocardiography is far from being a widespread practice in Japan. This might be due to insufficient equipment (e.g., ergometers, space for test implementation) at each medical institution, shortage of technicians and sonographers who are well experienced and who are responsible for obtaining images during stress testing. The other possible reasons include the limited evidence available in Japan and the lack of a standardized testing protocol. Further dissemination of the practice of exercise stress echocardiography in this country is deemed necessary to establish satisfactory evidence for the use of stress echocardiography in the Japanese population. To this end, efforts are underway to develop a standardized protocol and report format to be adopted throughout Japan. We here present a guideline created by the Guideline Development Committee of the Japanese Society of Echocardiography that describes safe and effective stress echocardiography protocols and report formats. The readers are encouraged to perform exercise stress echocardiography using the proposed template for consensus document and report attached to this guideline.

Guideline from Japanese Society of Echocardiography: 2018 focused update incorporated into Guidance for the Management and Maintenance of Echocardiography Equipment

Echocardiography plays a pivotal role as an imaging modality in the modern cardiology practice. Information derived from echocardiography is definitely helpful for a patient care. The Japanese Society of Echocardiography has promoted echocardiography for a routine clinical and research use. One of the missions of the Society is to provide information that is useful for high-quality examinations. To ensure it, we believe equipment in good conditions and a comfortable environment are important for both a patient and an examiner. Thus, the Committee for Guideline Writing, the Japanese Society of Echocardiography published brief guidance for the routine use of echocardiography equipment in 2015. Recently, the importance of international standardization has been emphasized in the medical laboratories. Accordingly, the committee has revised and updated our guidance for the routine use of echocardiography equipment.

Waon Therapy for Managing Chronic Heart Failure - Results From a Multicenter Prospective Randomized WAON-CHF Study

BACKGROUND

Waon therapy improves heart failure (HF) symptoms, but further evidence in patients with advanced HF remains uncertain.

METHODS AND RESULTS

In 19 institutes, we prospectively enrolled hospitalized patients with advanced HF, who had plasma levels of B-type natriuretic peptide (BNP) >500 pg/ml on admission and BNP >300 pg/ml regardless of more than 1 week of medical therapy. Enrolled patients were randomized into Waon therapy or control groups. Waon therapy was performed once daily for 10 days with a far infrared-ray dry sauna maintained at 60℃ for 15 min, followed by bed rest for 30 min covered with a blanket. The primary endpoint was the ratio of BNP before and after treatment. In total, 76 Waon therapy and 73 control patients (mean age 66 years, men 61%, mean plasma BNP 777 pg/ml) were studied. The groups differed only in body mass index and the frequency of diabetes. The plasma BNP, NYHA classification, 6-min walk distance (6MWD), and cardiothoracic ratio significantly improved only in the Waon therapy group. Improvements in NYHA classification, 6MWD, and cardiothoracic ratio were significant in the Waon therapy group, although the change in plasma BNP did not reach statistical significance. No serious adverse events were observed in either group.

CONCLUSIONS

Waon therapy, a holistic soothing warmth therapy, showed clinical advantages in safety and efficacy among patients with advanced HF.

Immunoadsorption therapy for dilated cardiomyopathy using tryptophan column-A prospective, multicenter, randomized, within-patient and parallel-group comparative study to evaluate efficacy and safety

Over the past few decades, several cardiac autoantibodies have been reported in sera from patients with dilated cardiomyopathy (DCM). Immunoadsorption (IA) therapy is one of the therapeutic tools to remove such autoantibodies. The objective of this study was to investigate functional effects of IA therapy using a tryptophan column in severe DCM patients. Of 49 patients enrolled, 44 were randomized from 10 sites in Japan. IA therapy was conducted in 40 patients with DCM (refractory to standard therapy for heart failure, New York Heart Association [NYHA] class III/IV, left ventricular ejection fraction [LVEF] <30%). Mean echocardiographic LVEF was significantly improved (23.8 ± 1.3% to 25.9 ± 1.3%, P = 0.0015). However, mean radionuclide LVEF over 3 months of IA therapy was not significantly improved (20.8 ± 1.1% to 21.9 ± 1%, P = 0.0605). The cardiothoracic ratio was also significantly decreased (P = 0.0010). NYHA functional class (P < 0.0001), subjective symptoms assessed by a quality of life questionnaire (P = 0.0022), maximum oxygen consumption (P = 0.0074), and 6‐minute walk distance (P = 0.0050) were improved after IA therapy. Subgroup analysis revealed improvement of echocardiographic LVEF in patients with higher baseline autoantibody scores but not in those with lower scores. IA therapy improved subjective symptoms and exercise capacity in patients with refractory heart failure resulting from DCM. Favorable effect on cardiac function was noted in patients with higher autoantibody scores. J. Clin. Apheresis 31:535–544, 2016. © 2015 Wiley Periodicals, Inc.

Pharmacological conversion of atrial fibrillation in the patients of Graves' disease

BACKGROUND

Hyperthyroidism is one of the common causes of atrial fibrillation (AF), and AF is associated with increased morbidity and mortality due to thromboembolism. The sinus rhythm maintenance rate of hyperthyroidism-induced AF patients after conversion to sinus rhythm is excellent. The present study was undertaken to assess the efficacy and safety of bepridil, a multichannel blocker, in patients with hyperthyroidism-induced persistent AF.

METHODS AND RESULTS

Sixty-two patients with hyperthyroidism-induced persistent AF were treated with bepridil. Oral bepridil therapy resulted in conversion to sinus rhythm in 32 (51.6%) of the 62 patients. There were no significant differences in clinical characteristics between the responders and non-responders. At the observation period of an average of 23.9 months, the sinus rhythm maintenance rate was found to be 81.3%. Adverse effects consisted of abnormal QTc prolongation in 3 patients and sinus bradycardia in 10 patients. There was one death in which a causal association with bepridil could not be ruled out.

CONCLUSIONS

Bepridil is as beneficial treatment to convert AF for the patients with hyperthyroidism-induced persistent AF as it is for the patients with AF due to other causes. However, bepridil should be used with caution to avoid serious side effects.

Effects of anemia correction by erythropoiesis-stimulating agents on cardiovascular function in non-dialysis patients with chronic kidney disease

Anemia is a significant risk factor for patients with chronic kidney disease (CKD). Here, we investigated the effects of anemia correction on cardiac functions in CKD patients. Pre-dialysis CKD patients (n = 171) without known risk factors for cardiovascular disease (CVD) other than CKD with hemoglobin (Hb) concentrations < 10.0 g/dL were enrolled for evaluation of cardiac functions and biomarkers before and after the 16-week treatment of erythropoiesis-stimulating agents. The treatment significantly increased Hb concentrations in all patients who completed the study (n = 143, 8.91 ± 0.87 versus 11.27 ± 1.31 g/dL; n < 0.001) and among patients whose echocardiograms were available for evaluation (n = 77, 8.92 ± 0.94 versus 11.24 ± 1.13 g/dL; P < 0.001). The left ventricular mass index (LVMI) was decreased (121.3 ± 25.8 versus 114.7 ± 25.1 g/m(2), n = 77, P = 0.012) and significant correlation between the change in the LVMI and Hb concentration was noted (P = 0.011). The levels of B-type natriuretic peptide and human atrial natriuretic peptide, and the cardio-thoracic ratio were significantly increased among subjects with Hb concentrations < 11.0 g/dL at completion of the study. The changes in these parameters were significantly correlated with the Hb concentrations (P = 0.033, P = 0.011, and P < 0.001, respectively). No significant differences were observed in the electrocardiographic parameters. Correcting Hb levels higher than those conventionally recommended reduced left ventricular hypertrophy and myocardial stress, lowering risks for CVD in pre-dialysis CKD patients.

Effect of lesional differences in prolapsed leaflets on clinical outcomes in patients with mitral valve prolapse

BACKGROUND

Mitral valve prolapse (MVP) is usually benign, although serious complications may occur. It remains unclear whether the region of prolapsed mitral leaflets might affect prognosis. The aim of this study was to investigate lesional differences of clinical courses of MVP.

METHODS AND RESULTS

We retrospectively investigated 128 MVP patients who had been followed up for for a mean of 56.4 months. They were classified into prolapse of the anterior mitral leaflet (AML, n = 59), posterior mitral leaflet (PML, n = 47), or both leaflets (AML & PML, n = 22). Echocardiographic and clinical data were examined from medical records. Average time to clinical events; MV surgery, new onset of atrial fibrillation (AF), echocardiographic evidence of new chordal rupture, and worsening of mitral regurgitation severity were all significantly shorter in PML prolapse than in those with AML or AML & PML prolapses. Increases in the left ventricular dimensions and estimated pulmonary arterial systolic pressures were significantly larger in PML prolapse, compared with AML or AML & PML prolapses. A subanalysis of PML prolapse revealed that new chordal rupture tended to be more frequent in middle scallop prolapse (48%) compared with lateral and medial scallops (18%). In contrast, new onset of AF tended to occur in lateral and medial scallop prolapses (44%) compared with middle scallop prolapse (20%).

CONCLUSIONS

PML prolapse patients had a poor outcome, compared with AML or AML & PML prolapse patients. Precise regional evaluation of the prolapsed leaflets may predict cardiac complications in MVP.

Positive outcomes of high hemoglobin target in patients with chronic kidney disease not on dialysis: a randomized controlled study

Correcting anemia in patients with chronic kidney disease (CKD) to higher hemoglobin (Hb) levels may be associated with increased risk. No optimal target for Hb has been established. This controlled study examined 321 patients with CKD who were not on dialysis, had a Hb level of <10g/dL, and a serum creatinine of 2.0 to 6.0mg/dL. They were randomized into two target Hb groups: 161 to high Hb (11.0-13.0g/dL) to receive darbepoetin alfa and low Hb to 160 (9.0-11.0g/dL) to receive recombinant erythropoietin. The study lasted 48weeks. Of 154 and 153 patients with adverse events, cardiovascular adverse events developed in 42 and 51 patients in the high and low Hb groups, respectively, with no significant difference in the incidence. All quality of life scores improved in the high Hb group and vitality improved significantly more with high Hb (P=0.025). The left ventricular mass index (LVMI) remained stable in the low Hb group, but there was a significant decrease in LVMI in the high group (P<0.001). There were no safety concerns with targeting a higher Hb level during the 48weeks of this study. Patients with a higher Hb target had comparatively better outcomes with respect to quality of life and LVMI.

Specific immunoadsorption therapy using a tryptophan column in patients with refractory heart failure due to dilated cardiomyopathy

BACKGROUND

Certain cardiac-specific autoantibodies found in patients with dilated cardiomyopathy (DCM) play a role in mediating myocardial damage and fatal ventricular arrhythmias resulting in sudden cardiac death. Immunoadsorption therapy (IA) is one of the therapeutic tools to remove such autoantibodies. Clinical studies from Germany have shown that nonspecific IA using columns loaded by sheep antihuman IgG or protein A improved hemodynamic data and affected favorably cardiac function and survival in patients with heart failure (HF) due to DCM. The goal of this study is to determine if IA therapy using the high-profile tryptophan column, which has high affinity for IgG3 subclass, affects favorably cardiac function in patients with severe HF who are refractory to conventional therapy.

METHODS AND RESULTS

IA therapy was conducted in 16 patients with DCM (age 53 ± 4, male 8, New York Heart Association functional class III/IV, mean ejection fraction 18 ± 2%). Study subjects had autoantibodies directed against either β1-adrenergic or M2-muscarinic receptors. Plasma brain natriuretic peptide levels were significantly decreased after IA (P = 0.016). Plasma inflammatory cytokines including interleukin-6 and tumor necrosis factor-α did not change after each session of IA. Six-minute walk distance was significantly increased after IA (P = 0.01). Left ventricular ejection fraction increased by 3% 3 months after IA (P = 0.039).

CONCLUSIONS

Our initial experience demonstrated safety and short-term efficacy of IA using a new IgG3-specific tryptophan column for patients with advanced HF due to DCM. Long-term follow-up is needed to confirm the effects on cardiac function and morbidity/mortality in such patients.

Phosphorus: an elemental catalyst for diamond synthesis and growth

As diamond-producing catalysts, 12 transition metals such as iron, cobalt, and nickel were first reported by General Electric researchers more than 30 years ago. Since then, no additional elemental catalyst has been reported. An investigation of the catalytic action of group V elements is of great interest from the viewpoint of producing an n-type semiconducting diamond crystal. In the present study, diamond was synthesized from graphite in the presence of elemental phosphorus at high pressure and temperature (7.7 gigapascals and 1800 degrees C). Furthermore, single-crystal diamond was grown on a diamond seed crystal.

Complete elimination of cardiodepressant IgG3 autoantibodies by immunoadsorption in patients with severe heart failure

BACKGROUND

Cardiodepressant IgG3 autoantibodies (CD-Abs) can be targeted by apheresis. Using blinded measurements of CD-Abs before and after immunoadsorption (IA), the cardiac function of patients who did or did not achieve complete CD-Abs elimination was compared.

METHODS AND RESULTS

Autoantibodies were completely removed from 18 patients with heart failure (New York Heart Association class 3 or 4, left ventricular ejection fraction (LVEF) <30%) using a selective IgG3 adsorption column. All patients had anti-beta1-adrenergic and/or M2-muscarinic autoantibodies before IA, and all LVEF were measured on radionuclide ventriculography. CD-Abs were measured before and after IA, and patient status was blinded until all measurements were collected. Treatment was defined as complete when CD-Abs status changed from positive to negative after IA. Other instances were defined as incomplete. Six-min walk test results and brain natriuretic peptide levels improved significantly after IA (P<0.01). The increase in LVEF 3 months after IA was significantly greater after complete treatment in comparison to the incomplete treatment group (19+/-8-29+/-9% vs 18+/-9-17+/-8%, P<0.01). Cardiac insufficiency events were also more frequent in the incomplete treatment group.

CONCLUSIONS

Complete elimination of CD-Abs with apheresis may be related to improved cardiac function in the treatment of heart failure.

A case of echocardiographic evaluation of ruptured pseudoaneurysm of the mitral-aortic intervalvular fibrosa by infective endocarditis

This report describes an unusual case of ruptured pseudoaneurysm (PSA) of mitral-aortic intervalvular fibrosa (MAIVF) caused by infective endocarditis. The PSA ruptured into the left sinus of Valsalva in addition to the left atrium, resulting in complicated shunting among the aorta, left ventricle and left atrium, leading to refractory heart failure. The transesophageal echocardiography provided the precise information concerning the anatomical detail of the PSA, which is crucial for the surgical repair. This is the first report describing a patient with PSA of MAIVF with two rupture sites.

A low-cost digital filing system for echocardiography data with MPEG4 compression and its application to remote diagnosis

The high cost of digital echocardiographs and the large size of data files hinder the adoption of remote diagnosis of digitized echocardiography data. We have developed a low-cost digital filing system for echocardiography data. In this system, data from a conventional analog echocardiograph are captured using a personal computer (PC) equipped with an analog-to-digital converter board. Motion picture data are promptly compressed using a moving pictures expert group (MPEG) 4 codec. The digitized data with preliminary reports obtained in a rural hospital are then sent to cardiologists at distant urban general hospitals via the internet. The cardiologists can evaluate the data using widely available movie-viewing software (Windows Media Player). The diagnostic accuracy of this double-check system was confirmed by comparison with ordinary super-VHS videotapes. We have demonstrated that digitization of echocardiography data from a conventional analog echocardiograph and MPEG 4 compression can be performed using an ordinary PC-based system, and that this system enables highly efficient digital storage and remote diagnosis at low cost.

Current characteristics of infective endocarditis in Japan: an analysis of 848 cases in 2000 and 2001

The Japanese Circulation Society appointed a committee to develop guidelines for the prevention, diagnosis and management of infective endocarditis in Japan. In making such guidelines, the committee required information on the current clinical characteristics of infective endocarditis and therefore performed a nationwide questionnaire survey of cases from 2000 and 2001. In total, data were received for 848 cases from 277 of the 817 hospitals surveyed. Mean age was 55+/-18 years and most patients were aged in their 50 s or 60 s; 53.9% of the patients had infective endocarditis of unknown origin (without any prior predisposing conditions or procedures) and the second most common etiology was post dental procedures. The most common microorganism was Gram-positive cocci (345 streptococci and 221 staphylococci) and methicillin resistant Staphylococcus aureus (MRSA) was found in 7.3%. Although more than 90% of cases with Streptococcus viridans were sensitive to penicillin G, 6.6% were resistant. All MRSAs were sensitive to vancomycin. The information obtained from the survey assisted in the making of the guidelines, which should become an indispensable tool for all clinicians.

Autoantibodies against M2-muscarinic acetylcholine receptors: new upstream targets in atrial fibrillation in patients with dilated cardiomyopathy

AIM

To characterise the clinical significance of M2-muscarinic acetylcholine receptor autoantibodies (M2-AAB) in patients with dilated cardiomyopathy (DCM).

METHODS AND RESULTS

Sera from 104 patients with DCM, age-matched with 104 patients with idiopathic atrial fibrillation (Af) and 104 healthy control subjects, were screened for M2-AAB by enzyme-linked immunosorbent assay (ELISA). IgG purified by Protein-A column was also used as a primary antibody in ELISA. In DCM, M2-AAB were detected in 40% of patients using whole sera and in 36% of patients using purified IgG. M2-AAB were also found in several patients with idiopathic Af (23%, 23%), and these frequencies were significantly higher than those in healthy subjects (8%, 8%). Af was more common in AAB-positive than in AAB-negative patients with DCM. Multivariable analysis confirmed that M2-AAB were independent predictors of the presence of Af in such patients. We determined electrophysiological changes by adding patient purified M2-AAB to chick embryos. Purified IgG from both Af and DCM patients exhibited negative chronotropic effects and induced supraventricular arrhythmias.

CONCLUSION

M2-AAB may play a role in mediating the development of Af in patients with DCM.

[Comparison of myocardial perfusion imaging by thallium-201 single-photon emission computed tomography with SUNY4001 (adenosine) and exercise--crossover clinical trial at multi-center]

We compared the ischemic diagnosis ability and adverse events of 201Tl myocardial perfusion imaging with SUNY4001 (adenosine) stress to that with exercise (ergometer) stress both on random crossover trial. Thirty one known or suspected chronic stable angina patients who are able to exercise and 10 healthy volunteers were enrolled for the trial. The early and delayed images were obtained by SPECT imaging. The concordance of diagnoses [ischemia vs. no ischemia] between the two types of stresses was 97.3% (36/37) [Kappa: 0.9068]. The sensitivity and specificity based on the exercise test were 100% (6/6) and 96.8% (30/31) respectively. The incidence of adverse events caused by SUNY4001 and the exercise were 44.7% (17/38) and 52.6% (20/38), respectively. Major adverse events caused by SUNY4001 were BP decrease, flushing and headache. And those by exercise were ST decrease, dyspnea and chest pain. None of the adverse events required the intervention or caused life-threatening complication in the trial. The trial showed that the ischemic diagnosis ability and safety of 201Tl scintigraphy with SUNY4001 stress are almost equal to those of the exercise stress that is considered as the standard stress method. We concluded that 201Tl imaging with SUNY4001 is safe and useful for detecting ischemic heart disease, especially for patients unable to exercise adequately.

[Autoantibodies: new upstream targets of paroxysmal atrial fibrillation in patients with congestive heart failure]

OBJECTIVES

The clinical implications of autoantibodies (Abs) were investigated as upstream indicators of paroxysmal atrial fibrillation in patients with congestive heart failure.

METHODS

Circulating Abs against myosin (M-Abs) detected by immunofluorescence, Abs against beta 1-adrenergic receptors (Beta 1-Abs) detected by enzyme-linked immunosorbent assay (ELISA), and Abs against NA-K-ATPase (NKA-Abs) detected by ELISA were screened in 95 congestive heart failure patients with < or = 45% left ventricular ejection fraction (coronary artery disease, n = 48; dilated cardiomyopathy, n = 47) and 48 age-matched control patients with hypertension. No patient received antiarrhythmic therapy. All patients were enrolled with angiotensin converting enzyme inhibitors in the chronic stable state. Relationship of the presence of paroxysmal atrial fibrillation to other clinical variables were assessed by 48-hour Holter monitoring.

RESULTS

No control patient had Abs. However, M-Abs, Beta 1-Abs, and NKA-Abs were detected in 22%, 26% and 16% of patients with congestive heart failure (coronary artery disease; 8%, 10%, and 4%, dilated cardiomyopathy; 36%, 43%, and 28%, respectively). Paroxysmal atrial fibrillation was more frequent in patients with dilated cardiomyopathy than in those with coronary artery disease (47% vs 15%, p < 0.01). Multivariate analysis suggested that NKA-Abs was an independent risk factor for the occurrence of paroxysmal atrial fibrillation (p < 0.01), although there were no differences in other clinical factors: age, sex, New York Heart Association functional class, concomitant medication, left ventricular ejection fraction, left atrial diameter, severity of mitral regurgitation, serum potassium, plasma norepinephrine, and atrial natriuretic peptide concentration.

CONCLUSIONS

Autoantibodies against sarcolemmal Na-K-ATPase were closely related to the occurrence of paroxysmal atrial fibrillation in patients with congestive heart failure, so an autoimmune process may be an upstream factor in atrial fibrillation.

[Autoantibodies against sarcolemmal Na-K-ATPase in patients with dilated cardiomyopathy: autoimmune basis for ventricular arrhythmias in patients with congestive heart failure]

BACKGROUND

Autoimmunity is one of the mechanisms of pathogenesis of idiopathic dilated cardiomyopathy (DCM) as well as virus infection and genetic predisposition. Autoantibodies against sarcolemmal Na-K-ATPase may be involved in the development of ventricular tachycardia and cardiac sudden death in patients with DCM.

METHODS AND RESULTS

By using enzyme-linked immunosorbent assay, autoantibodies were detected in 26% patients with DCM and in 2% age-matched control subjects. Na-K-ATPase activity in the presence of patient IgG was lower in patients with autoantibodies than without autoantibodies, but there was no difference in the control subjects. Western blots showed that autoantibodies recognized the alpha-subunit of Na-K-ATPase, and 3H-ouabain bindings in the presence of patient IgG showed that the dissociation constant was higher in patients with autoantibodies than without autoantibodies, although maximal binding sites were similar between the two groups. No difference existed between subjects with regard to age, sex, New York Heart Association functional class, cardiac function, or neurohormone levels, except for plasma norepinephrine which was higher in patients with autoantibodies than without autoantibodies, Ventricular arrhythmias were more common in patients with autoantibodies than without autoantibodies, and multiple logistic regression analysis demonstrated that the presence of autoantibodies, but not plasma norepinephrine, was an independent predictor for the occurrence of ventricular tachycardia. Cardiac sudden death was independently predicted by the presence of autoantibodies, as well as poor systolic function.

CONCLUSIONS

Patients with DCM express autoantibodies against sarcolemmal Na-K-ATPase, and these autoantibodies could be responsible for the electrical instability in some patients.

Characterization of anti-myocardial autoantibodies in Japanese patients with dilated cardiomyopathy

Few previous reports have comprehensively screened all the anti-myocardial autoantibodies (AMCA) in relation to other clinical profiles in patients with idiopathic dilated cardiomyopathy (IDC), so the present study used both immunohistochemistry (FITC) and immunoblotting (IB) for screening patients with IDC in order to characterize the clinical significance of AMCA. Sera were collected from 100 patients with IDC and age-matched 100 healthy control subjects (CTL). For FITC, an unfixed frozen section of human myocardium was used for the standard indirect immunofluorescence; for IB, total cardiac homogenates of the same myocardium were blotted to serum at 2 sets of dilution (1:200 and 1:10,000). The positive rates of AMCA detection for each method were as follows (IDC vs CTL); 39% vs 6% for FITC, 38% vs 4% for IB (1:200), and 10% vs 0% for IB (1:10,000). Fifty-nine patients with IDC and 8 CTL were positive for AMCA by either method, and 18 patients with IDC and 2 CTL were positive for AMCA by both methods. IB-positivity at 1:200 was an independent predictor by multiple logistic regression analysis of non-sustained ventricular tachycardias as well as left ventricular end-diastolic diameter and plasma norepinephrine concentration.

Age-adjusted heart rate variability as an index of the severity and prognosis of heart failure

The age-adjusted, heart rate variability (HRV) was evaluated as a parameter for the severity of heart failure and its prognosis. HRV was obtained by 24-h Holter monitoring in patients with left ventricular dysfunction (LVD). New York Heart Association (NYHA) functional classification, echocardiography, radioisotope ventriculography, and blood examination were performed, and compared between patients and normal subjects. The evaluation was repeated during the follow-up period. Finally, using the lower limit of HRV, patients were divided into either normal or abnormal group for each low-frequency power (LF) and high-frequency power (HF) (age-adjusted HRV). Other parameters of heart failure and prognosis were compared between these 2 groups. HRV tended to be lower in patients with LVD. HF decreased at the early stage of heart failure, but did not decrease progressively. LF decreased progressively. HRV change paralleled the change of NYHA. The abnormal HRV group showed a poor prognosis for cardiac death, but not for sudden cardiac death. In patients with LVD, HRV was decreased compared with the normal subjects. Change in HRV correlated with the change in NYHA classification. Age-adjusted HRV correlated with cardiac-death prognosis, but not for sudden cardiac death.

Neurohumoral activations in congestive heart failure: correlations with cardiac function, heart rate variability, and baroreceptor sensitivity

BACKGROUND

The clinical significance of the determination of heart rate variability and baroreceptor sensitivity relating to cardiac function and neurohumoral factors remains to be established.

METHODS AND RESULTS

We investigated the relation between conventional clinical variables and frequency domain analysis of heart rate variability and baroreceptor sensitivity in 146 patients with heart failure. Cardiac function including left ventricular ejection fraction, left ventricular dimensions, and left atrial size was different by the plasma atrial natriuretic peptide level but not by the norepinephrine level. The total power and low-frequency power were correlated with plasma norepinephrine, whereas baroreceptor sensitivity was correlated with plasma atrial natriuretic peptide. None of the frequency domain variables and baroreceptor sensitivity was correlated with cardiac function. There was a positive correlation between the low-frequency power and baroreceptor sensitivity.

CONCLUSIONS

Heart rate variability and baroreceptor sensitivity, which reflect autonomic regulation, may be an indicator independent from cardiac function in patients with heart failure.