Kazuaki Kaitani

Long-Term Clinical and Angiographic Follow-Up After Coronary Stent Placement in Native Coronary Arteries

Background—Although coronary stents have been proved effective in reducing clinical cardiac events for up to 3 to 5 years, longer term clinical and angiographic outcomes have not yet been fully clarified. Methods and Results—To evaluate longer term (7 to 11 years) outcome, clinical and angiographic follow-up information was analyzed in 405 patients with successful stenting in native coronary arteries. Primary or secondary stabilization, which was defined as freedom from death, coronary artery bypass grafting, and target lesion-percutaneous coronary intervention (TL-PCI) during the 14 months after the initial procedure or after the last TL-PCI, was achieved in 373 patients (92%) overall. Only 7 patients (1.7%) underwent TL-PCI more than twice. After the initial 14-month period, freedom from TL-PCI reached a plateau at 84.9% to 80.7% over 1 to 8 years. However, quantitative angiographic analysis in 179 lesions revealed a triphasic luminal response characterized by an early restenosis phase until 6 months, an intermediate-term regression phase from 6 months to 3 years, and a late renarrowing phase beyond 4 years. Minimal luminal diameter in 131 patients with complete serial data were 2.62±0.4 mm immediately after stenting, 2.0±0.49 mm at 6 months, 2.19±0.49 mm at 3 years, and 1.85±0.56 mm beyond 4 years (P <0.0001). Conclusions—The efficacy and safety of coronary stenting seemed to be clinically sustained at 7 to 11 years of follow-up. However, late luminal renarrowing beyond 4 years was common, which demonstrates the need for further follow-up.

Adenosine triphosphate-guided pulmonary vein isolation for atrial fibrillation: the UNmasking Dormant Electrical Reconduction by Adenosine TriPhosphate (UNDER-ATP) trial.

AIMS Most of recurrent atrial tachyarrhythmias after pulmonary vein isolation (PVI) for atrial fibrillation (AF) are due to reconnection of PVs. The aim of the present study was to evaluate whether elimination of adenosine triphosphate (ATP)-induced dormant PV conduction by additional energy applications during the first ablation procedure could reduce the incidence of recurrent atrial tachyarrhythmias. METHODS AND RESULTS We randomly assigned 2113 patients with paroxysmal, persistent, or long-lasting AF to either ATP-guided PVI (1112 patients) or conventional PVI (1001 patients). The primary endpoint was recurrent atrial tachyarrhythmias lasting for >30 s or those requiring repeat ablation, hospital admission, or usage of Vaughan Williams class I or III antiarrhythmic drugs at 1 year with the blanking period of 90 days post ablation. Among patients assigned to ATP-guided PVI, 0.4 mg/kg body weight of ATP provoked dormant PV conduction in 307 patients (27.6%). Additional radiofrequency energy applications successfully eliminated dormant conduction in 302 patients (98.4%). At 1 year, 68.7% of patients in the ATP-guided PVI group and 67.1% of patients in the conventional PVI group were free from the primary endpoint, with no significant difference (adjusted hazard ratio [HR] 0.89; 95% confidence interval [CI] 0.74-1.09; P = 0.25). The results were consistent across all the prespecified subgroups. Also, there was no significant difference in the 1-year event-free rates from repeat ablation for any atrial tachyarrhythmia between the groups (adjusted HR 0.83; 95% CI 0.65-1.08; P = 0.16). CONCLUSION In the catheter ablation for AF, we found no significant reduction in the 1-year incidence of recurrent atrial tachyarrhythmias by ATP-guided PVI compared with conventional PVI.

Efficacy of Antiarrhythmic Drugs Short-Term Use After Catheter Ablation for Atrial Fibrillation (EAST-AF) trial

AIMS Substantial portion of early arrhythmia recurrence after catheter ablation for atrial fibrillation (AF) is considered to be due to irritability in left atrium (LA) from the ablation procedure. We sought to evaluate whether 90-day use of antiarrhythmic drug (AAD) following AF ablation could reduce the incidence of early arrhythmia recurrence and thereby promote reverse remodelling of LA, leading to improved long-term clinical outcomes. METHODS AND RESULTS A total of 2038 patients who had undergone radiofrequency catheter ablation for paroxysmal, persistent, or long-lasting AF were randomly assigned to either 90-day use of Vaughan Williams class I or III AAD (1016 patients) or control (1022 patients) group. The primary endpoint was recurrent atrial tachyarrhythmias lasting for >30 s or those requiring repeat ablation, hospital admission, or usage of class I or III AAD at 1 year, following the treatment period of 90 days post ablation. Patients assigned to AAD were associated with significantly higher event-free rate from recurrent atrial tachyarrhythmias when compared with the control group during the treatment period of 90 days [59.0 and 52.1%, respectively; adjusted hazard ratio (HR) 0.84; 95% confidence interval (CI) 0.73-0.96; P = 0.01]. However, there was no significant difference in the 1-year event-free rates from the primary endpoint between the groups (69.5 and 67.8%, respectively; adjusted HR 0.93; 95% CI 0.79-1.09; P = 0.38). CONCLUSION Short-term use of AAD for 90 days following AF ablation reduced the incidence of recurrent atrial tachyarrhythmias during the treatment period, but it did not lead to improved clinical outcomes at the later phase.

Unexpectedly High Prevalence of Acquired von Willebrand Syndrome in Patients with Severe Aortic Stenosis as Evaluated with a Novel Large Multimer Index

AIM Severe gastrointestinal bleeding sometimes occurs in patients with aortic stenosis (AS), known as Heydes syndrome. This syndrome is thought to be caused by acquired von Willebrand syndrome and is characterized by reduced large von Willebrand factor (vWF) multimers. However, the relationship between the severity of AS and loss of large vWF multimers is unclear. METHODS We examined 31 consecutive patients with severe AS. Quantitative evaluation for loss of large vWF multimers was performed using the conventional large vWF ratio and novel large vWF multimer index. This novel index was defined as the ratio of large multimers of patients to those of controls. RESULTS Loss of large vWF multimers, defined as the large vWF multimer index ＜80%, was detected in 21 patients (67.7%). The large vWF multimer ratio and the large vWF multimer index were inversely correlated with the peak aortic gradient (R = -0.58, p=0.0007, and R=-0.64, p＜0.0001, respectively). Anemia defined as hemoglobin ＜9.0 g/dl was observed in 12 patients (38.7%), who were regarded as Heydes syndrome. Aortic valve replacement was performed in 7 of these patients, resulting in the improvement of anemia in all patients from a hemoglobin concentration of 7.5±1.0 g/dl preoperatively to 12.4±1.3 g/dl postoperatively (p＜0.0001). CONCLUSIONS Acquired von Willebrand syndrome may be a differential diagnosis in patients with AS with anemia. The prevalence of AS-associated acquired von Willebrand syndrome is higher than anticipated.

Late re-conduction sites in the second session after pulmonary vein isolation using adenosine provocation for atrial fibrillation

AIMS Intravenous adenosine triphosphate (ATP) administration could reveal dormant conduction (DC) gaps on the ablation line of a pulmonary vein isolation (PVI). We compared the ATP-provoked DC sites in the initial PVI with the PV re-conduction sites in the second session in patients with paroxysmal atrial fibrillation (AF). METHODS AND RESULTS We conducted a multicenter, observational study from a prospective registry undergoing AF ablation. A total of 110 consecutive drug-refractory paroxysmal AF patients were enroled in this study. Dormant conduction was detected by an ATP provocation of up to 40 mg during a continuous isoproterenol infusion (0.5-2 μg/min). The DC sites at each of the right and left PVs were precisely determined by using double spiral catheters under the guidance of a three-dimensional constructed anatomical mapping system. In the initial session, DC was observed in 35 patients (31.8%, 1.3 gaps/patient), and the sites of the DC were commonly observed in the carina region (43.5%). Atrial fibrillation recurrence was confirmed in 33 patients (30.0%) during follow-up (27.1 months), and a second session was performed in 24 of 33 patients (70.6%). In the second session, the re-conduction sites were also commonly observed in the carina region (59.5%). CONCLUSION The carina region was still a dominant re-conduction site even after the elimination of any ATP-provoked DC in the index procedure.

Predictors of Rapid Progression and Clinical Outcome of Asymptomatic Severe Aortic Stenosis.

BACKGROUND The optimal timing of aortic valve replacement (AVR) is controversial in patients with asymptomatic severe aortic stenosis (AS) except when very severe. Prediction of progression of severe AS is helpful in deciding on the timing of AVR. The purpose of this study was to clarify the predictors of progression rate and clinical outcomes of severe AS. METHODSANDRESULTS We retrospectively investigated 140 consecutive patients with asymptomatic severe AS (aortic valve area [AVA], 0.75-1.0 cm(2)). First-year progression rate and annual progression rate of AVA and of aortic jet velocity (AV-Vel) were calculated. Cardiac events were examined and the predictors of rapid progression and cardiac events were analyzed. The median follow-up period was 36 months. The median annual progression rate was -0.05 cm(2)/year for AVA and 0.22 m/s/year for AV-Vel. Dyslipidemia, moderate-severe calcification, and first-year AV-Vel progression ≥0.22 m/s/year were independent predictors of cardiac events. Cardiac event-free rate was lower in patients with AV-Vel first-year progression rate ≥0.22 m/s/year than in those with a lower rate. Diabetes and moderate-severe calcification were related to first-year rapid progression. CONCLUSIONS The annual progression rate of severe AS was -0.05 cm(2)/year for AVA and 0.22 m/s/year for AV-Vel. Patients with first-year rapid progression or severely calcified aortic valve should be carefully observed while considering an early operation. (Circ J 2016; 80: 1863-1869).

Multiple Coronary Artery Aneurysms and Thoracic Aortitis Associated with IgG4-related Disease

A 60-year-old man was admitted due to the onset of right coronary artery (RCA) aneurysms. Coronary angiography showed two RCA aneurysms and focal stenosis with limitations in the blood flow. Balloon angioplasty was performed. However, the follow-up coronary angiography showed restenosis, an enlarged proximal aneurysm and a newly formed aneurysm. The serum immunoglobulin G4 level was elevated to 1,350 mg/dL and fluorodeoxyglucose positron emission tomography showed increased uptake in the ascending aorta, so the patient was diagnosed with immunoglobulin G4-related vascular disease. The prevention of further enlargement of the aneurysms and an improvement in the RCA flow were achieved with steroid therapy. Steroid therapy may therefore be effective for immunoglobulin G4-related vascular disease.

Relationship between plasma dabigatran concentration and activated partial thromboplastin time in Japanese patients with non-valvular atrial fibrillation

Activated partial thromboplastin time (aPTT) is recommended for monitoring anticoagulant activity in dabigatran‐treated patients; however, there are limited data in Japanese patients. To clarify the relationship between plasma dabigatran concentration and aPTT, we analyzed plasma dabigatran concentration and aPTT at various time points following administration of oral dabigatran in a Japanese hospital.

Effect of radiofrequency catheter ablation of persistent atrial fibrillation on the left atrial function: Assessment by 320-row multislice computed tomography

BACKGROUND Atrial fibrillation (AF) increases the left atrial (LA) volume and deteriorates LA function. Whether successful radiofrequency catheter ablation (RFCA) of persistent AF can reverse this process has not been yet established. METHODS Patients with persistent AF undergoing RFCA were evaluated with pre- and post- (at 6-months of follow-up) procedural multislice computed tomography (MSCT). The LA functions were assessed through LA time-volume curves. RESULTS The study population consisted of 44 patients [age 64 (interquartile ranges: 58, 70) years old, 93% male]. Among those, 31 patients (70%) maintained sinus rhythm during the follow-up (no recurrence group; NR group). The remaining 13 patients were classified as the recurrence group (R group). A significant decrease in the minimal and maximal LA volumes was observed in both groups, although this was less pronounced in the R group. Only the NR group had an improvement in the LA expansion index [18% (13, 25) vs. 37% (23, 43), p<0.001], ejection fraction [15% (11, 20) vs. 27% (19, 30), p<0.001] and conduit function [17 ml/m(2) (13, 20) vs. 25 ml/m(2) (20, 34), p<0.001]. An improvement of LV function was also observed only in the NR group. CONCLUSIONS LA anatomical and functional reverse remodeling after RFCA of persistent AF was demonstrated by MSCT during follow-up, which was more pronounced in patients without AF recurrence.

Cardiac tamponade during transesophageal echocardiography in a patient with infective endocarditis.

An 81-year-old man with a history of diabetes mellitus and end-stage renal disease was admitted because of infective endocarditis. During transesophageal echocardiography (TEE), pericardial effusion rapidly increased and led to cardiac tamponade. Despite intensive therapy, the patient did not recover. Autopsy showed hemopericardium, ruptured sinus of Valsalva, and vegetation on the aortic valve. Our case suggests that cardiac tamponade due to the rupture of a sinus of Valsalva can occur in patients with aortic valve endocarditis complicated by perivalvular abscess. Therefore, we must be aware of this devastating complication and take preventive measures when performing TEE in such patients.