Takamichi Miyamoto

Adenosine triphosphate-induced atrial fibrillation: the clinical significance and relevance to spontaneous atrial fibrillation

PurposeAdenosine triphosphate (ATP) frequently triggers atrial fibrillation (AF), but the clinical significance of this phenomenon is unknown. The purpose of this study was to reveal the relevance between spontaneous AF and ATP-induced AF.MethodsIn 81 AF patients undergoing pulmonary vein isolation (PVI), we injected 20 mg of ATP before PVI, and recorded triggering sites of the AF induced. We also injected 20 mg of ATP in 44 patients receiving ablation for atrioventricular reciprocating tachycardia (AVRT).ResultsATP provoked AF in 24 (29.6 %) of the 81 PVI patients and atrial ectopic beats in a further 48 (59.3 %). The trigger site of the AF was in the PV and the right atrium in 22 (91.7 %) and 2 patients, respectively. In 14 of those 24 patients, spontaneous AF arose from the same triggering site as the ATP-induced AF. In the 48 patients with ATP-provoked ectopic beats, spontaneous AF arose from the same site in 13. Conversely, among the 34 patients demonstrating spontaneous AF initiation, AF or ectopic beats were provoked by ATP from the same site in 14 (41.2 %) and 13 patients (38.2 %), respectively. ATP provoked AF in only 2 (4.5 %) of the AVRT patients. In summary, ATP provoked AF or atrial ectopic beats in 88.9 % of PVI patients, 36.1 % of whose triggering sites matched that of the spontaneous AF, while 79.4 % of spontaneous AF trigger sites matched ATP-provoked AF or ectopic beat sites. ConclusionsATP-induced AF was strongly associated with clinical AF, and ATP is useful for identifying arrhythmogenic sites.

Predictive Value of QRS Duration at Admission for In-Hospital Clinical Outcome of Takotsubo Cardiomyopathy

BACKGROUND Prolonged QRS duration (pQRSd) on electrocardiogram (ECG) is a strong predictor of poor outcome in heart failure, myocardial infarction, and myocarditis, but it is unclear whether pQRSd also predicts poor outcomes of takotsubo cardiomyopathy (TC).Methods and Results:Between 1 January 2010 and 31 December 2012, we retrospectively enrolled 299 patients with TC (mean age, 73.5±11.7 years; 21.4% male) from the Tokyo CCU Network database, which consists of 71 cardiovascular centers in the metropolitan area. In-hospital clinical outcomes were compared between patients with pQRSd on admission ECG (QRS ≥120 ms; n=34) and those with normal QRS duration (<120 ms; n=265). The in-hospital mortality rate for pQRSd was significantly higher than that for normal QRS duration (23.5% vs. 3.8%, P<0.001). Similarly, prevalence of ventilator use (38.2% vs. 11.4%, P<0.001), ventricular tachycardia or fibrillation (14.7% vs. 1.5%, P<0.001), and circulatory failure requiring catecholamine or cardiopulmonary supportive devices (41.2% vs. 14.0%, P<0.001) was significantly higher in the pQRSd group. On multivariate logistic regression analysis, pQRSd was an independent predictor for both in-hospital mortality (OR, 5.06; 95% CI: 1.79-14.30, P=0.002) and cardiac death (OR, 7.34; 95% CI: 1.33-40.51, P=0.02). CONCLUSIONS TC with pQRSd is associated with poor in-hospital clinical outcome. Aggressive intervention may be required to prevent severe complications in these patients.

Time Interval from Symptom Onset to Hospital Care in Patients with Acute Heart Failure: A Report from the Tokyo Cardiac Care Unit Network Emergency Medical Service Database

Aims There seems to be two distinct patterns in the presentation of acute heart failure (AHF) patients; early- vs. gradual-onset. However, whether time-dependent relationship exists in outcomes of patients with AHF remains unclear. Methods The Tokyo Cardiac Care Unit Network Database prospectively collects information of emergency admissions via EMS service to acute cardiac care facilities from 67 participating hospitals in the Tokyo metropolitan area. Between 2009 and 2011, a total of 3811 AHF patients were registered. The documentation of symptom onset time was mandated by the on-site ambulance team. We divided the patients into two groups according to the median onset-to-hospitalization (OH) time for those patients (2h); early- (presenting ≤2h after symptom onset) vs. gradual-onset (late) group (>2h). The primary outcome was in-hospital mortality. Results The early OH group had more urgent presentation, as demonstrated by a higher systolic blood pressure (SBP), respiratory rate, and higher incidence of pulmonary congestion (48.6% vs. 41.6%; P<0.001); whereas medical comorbidities such as stroke (10.8% vs. 7.9%; P<0.001) and atrial fibrillation (30.0% vs. 26.0%; P<0.001) were more frequently seen in the late OH group. Overall, 242 (6.5%) patients died during hospitalization. Notably, a shorter OH time was associated with a better in-hospital mortality rate (odds ratio, 0.71; 95% confidence interval, 0.51−0.99; P = 0.043). Conclusions Early-onset patients had rather typical AHF presentations (e.g., higher SBP or pulmonary congestion) but had a better in-hospital outcome compared to gradual-onset patients.

Effect of Heart Failure Secondary to Ischemic Cardiomyopathy on Body Weight and Blood Pressure

Both the obesity paradox and blood pressure (BP) paradox remain ill defined. Because both obesity and hypertension are well-known predictors of coronary artery disease (CAD) and acute heart failure (HF), in the present study, we compared the obesity paradox and the BP paradox between patients with acute HF with and without a history of CAD. A multicenter retrospective study was conducted on 3,204 consecutive patients with acute HF. Potential risk factors for in-hospital mortality were selected by univariate analyses; multivariate Cox regression analysis with backward stepwise selection was then used to identify significant factors. Kaplan-Meier survival curves and log-rank testing were used to compare in-hospital mortality between groups. Across the study cohort, 27% of patients had a history of CAD, and the all-cause in-hospital mortality rate was 5%. In-hospital mortality was significantly lower for patients with obesity than in those without obesity (log-rank, p = 0.033). However, this obesity paradox disappeared in the group with HF and CAD (log-rank, p = 0.740). In contrast, in-hospital mortality was significantly lower for patients with high BP at admission, regardless of the presence of a history of CAD (log-rank, p <0.001 for both groups). In conclusion, a history of CAD canceled the obesity paradox in patients with acute HF, whereas the BP paradox persisted regardless of a history of CAD.

Haemostasis with fibrin glue injection into the pericardial space for right ventricular perforation caused by an iatrogenic procedural complication

An 89-year-old woman with severe aortic valve stenosis and bradycardia presented with circulatory shock due to cardiac tamponade. We performed pericardiocentesis, and then diagnosed right ventricular perforation by echocardiography with microcavitation contrast medium just before inserting a drainage tube. We then inserted the drainage tube in the appropriate position and withdrew blood-filled fluid. The patient was haemodynamically stabilised, but haemorrhage from the perforation site continued for a few days. We injected fibrin glue into the pericardial space through the drainage tube and achieved haemostasis. Thus, we avoided surgery to close the perforation in this high-risk patient. There was no recurrence of haemorrhage. She subsequently had elective aortic valve replacement at another hospital. No adhesions in the pericardial space were seen during surgery.

Microcavitation Contrast Method for the Drainage of Bloody Pericardial Effusion

A 78-year-old woman experienced cardiac tamponade (Figure 1). At first, a drainage tube was inserted into the pericardial cavity through the fifth intercostal space guided by transthoracic echocardiography; however, the aspirate was bloody. We suspected that the tip of the …

Atrial fibrillation type matters: greater infarct volume and worse neurological defects seen in acute cardiogenic cerebral embolism due to persistent or permanent rather than paroxysmal atrial fibrillation

Aims Some studies have shown that the type of atrial fibrillation (AF), whether paroxysmal AF (PAF) or persistent or permanent AF (PeAF), affects the incidence of ischaemic stroke. This study sought to determine the relationship between the AF pattern and the severity and brain volume of infarction in an AF population including transient ischaemic attack (TIA) patients. Methods and results This was a retrospective observational study. We studied 161 consecutive patients who were admitted to our stroke care unit with cardiogenic embolism or TIA related to non-valvular AF (age 79 ± 9.5, 78 females, and 87 PAF patients). We evaluated the differences in severity and infarct volume between the types of AF. Additionally, we divided the patients into three groups according to severe stroke (n = 38), TIA (n = 28), and those who were neither (stroke, n = 95) for the assessment of the predictors of severe stroke and TIA. Persistent or permanent atrial fibrillation patients with acute cardiogenic stroke or TIA had worse peak National Institute of Health Stroke Scale (NIHSS) scores [PAF median 4 (range 3-14), PeAF 17 (5.8-25); P < 0.0001] and worse NIHSS scores at discharge [PAF 2.0 (1-7), PeAF 11 (3-22); P < 0.0001]. Their infarct brain volume assessed by computed tomography or magnetic resonance imaging was also larger [PAF 4.4 (1.1-32) mL, PeAF 64 (6.9-170) mL; P < 0.0001]. Multivariate analysis of severe stroke vs. non-severe stroke patients showed that having PeAF was the only independent predictor of severe stroke [odds ratio (OR) 4.27, 95% confidence interval (CI) 1.91-10.2; P = 0.0003]. Comparison of TIA vs. non-TIA patients showed that PeAF (OR 0.120, 95% CI 0.0230-0.444; P = 0.0008) and anticoagulant use (OR 8.24, 95% CI 2.15-40.8; P = 0.0018) were independent predictors of TIA. Conclusion Cardiogenic emboli due to non-valvular PeAF are associated with a worse acute clinical course and greater volume of infarction than those due to PAF.

Effect of Optimizing Guideline-Directed Medical Therapy Before Discharge on Mortality and Heart Failure Readmission in Patients Hospitalized With Heart Failure With Reduced Ejection Fraction

Guideline-directed medical therapy (GDMT) is recommended for patients with heart failure with reduced ejection fraction (HFrEF). However, the prognostic impact of medication optimization at the time of discharge in patients hospitalized with heart failure (HF) is unclear. We analyzed 534 patients (73 ± 13 years old) with HFrEF. The status of GDMT at the time of discharge (prescription of angiotensin converting enzyme inhibitor [ACE-I]/angiotensin receptor blocker [ARB] and β blocker [BB]) and its association with 1-year all-cause mortality and HF readmission were investigated. Patients were divided into 3 groups: those treated with both ACE-I/ARB and BB (Both group: n = 332, 62%), either ACE-I/ARB or BB (Either group: n = 169, 32%), and neither ACE-I/ARB nor BB (None group: n = 33, 6%), respectively. One-year mortality, but not 1-year HF readmission rate, was significantly different in the 3 groups, in favor of the Either and Both groups. A favorable impact of being on GDMT at the time of discharge on 1-year mortality was retained even after adjustment for covariates (Either group: hazard ratio [HR] 0.44, 95% confidence interval [CI] 0.21 to 0.90, p = 0.025 and Both group: HR 0.29, 95% CI 0.13-0.65, p = 0.002, vs None group). For 1-year HF readmission, no such association was found. In conclusion, optimization of GDMT before the time of discharge was associated with a lower 1-year mortality, but not with HF readmission rate, in patients hospitalized with HFrEF.

Prognosis of super-elderly healthy Japanese patients after pacemaker implantation for bradycardia

BACKGROUND The prognosis of super-elderly patients (age≥85 years) who undergo bradycardia pacemaker (PM) implantation remains unknown. METHODS We retrospectively enrolled 868 patients (men 49.0%, 76.6±10.6 years) who could walk unassisted and whose expected life expectancy was more than 1 year, receiving their first bradycardia PM implantation between January 1, 2006, and June 30, 2013. Clinical outcomes were compared between super-elderly patients (n=201, mean age 88.6±3.2 years) and younger patients (n=667, 73.0±9.3 years). RESULTS At the end of a median 1285-day follow-up, 128 patients (14.7%) died, of which 54 were cardiac deaths (42.2%). Mortality rates were similar between the groups (16.4% vs. 14.2%, log-rank p=0.56) and across different indications for implantation (atrio-ventricular conduction disturbance or sick sinus syndrome, p=0.59), initial rhythms (sinus rhythm or persistent atrial fibrillation, p=0.62), pacing modes (dual chamber pacing or VVI pacing, p=0.26), and ventricular lead positions (septum or apex, p=0.52). On Cox proportional hazard model analysis, hypertension [hazard ratio (HR)=1.74, 95% confidence interval (CI)=1.19-2.54, p=0.004], diabetes mellitus (HR=2.18, 95% CI=1.51-3.14, p<0.001), history of myocardial infarction (HR=3.59, 95% CI=2.49-5.16, p<0.001), and history of stroke (HR=2.26, 95% CI=1.51-3.37, p<0.001) were independent predictors for mortality. CONCLUSIONS The mortality rate of super-elderly patients who had no critical illnesses and were healthy enough to walk unassisted at the time of PM implantation was not inferior to that of younger patients. Prognosis was determined by comorbidities, but not by age, PM indication, initial rhythm, pacing leads, or mode.

Efficacy of Catheter Ablation and Concomitant Antiarrhythmic Drugs on the Reduction of the Arrhythmia Burden in Patients with Long-Standing Persistent Atrial Fibrillation

Background Little is known about the long-term outcome and recurrent form recurrence after catheter ablation of atrial fibrillation (AF) in patients with long-standing persistent AF. Methods Two hundred thirty-six patients with persistent AF (193 men; age, 61.5±10.7 years) were enrolled, and were classified according to the duration of AF: AF duration of <1 year (group A, n=99), between 1 to 5 years (group B, n=101), and ≥5 years (group C, n=36). The long-term recurrence rate and recurrent form were compared among the groups. Results During a median follow-up of 3.7 years, the recurrence rate was significantly worse in group C after the index and multiple procedures (Log-Rank, both for a P<0.001 in comparison to group A). In the multivariate analysis, the duration was an independent predictor of an arrhythmia recurrence (HR, 1.206; 95%CI, 1.053 to 1.381; P=0.007). Recurrent AF became permanent in 8 patients (3.4%), which was not associated with a difference in the groups (Log-rank, P=0.055), while antiarrhythmic drugs (AADs) were continued in 70% of the recurrent patients. Conclusion Despite a high AF recurrence rate in the patients with an AF duration of ≥5 years, the majority of the patients with recurrence who continued on AADs had a paroxysmal form of AF. Catheter ablation and concomitant AADs may be effective in reducing the AF burden in such patients with an advanced AF disease stage.