Occurrence of Potentially Lethal Arrhythmia due to Sudden Exposure of an Overt Accessory Pathway 8 Years After Catheter Ablation of a Concealed Accessory Pathway.

Although the efficacy of catheter ablation of the accessory pathway (AP) has been established, there are subgroups of APs with an intermittent conduction property, which is sometimes difficult to diagnose accurately. A 57-year-old man with a history of catheter ablation was referred to our clinic due to frequent faintness. He had undergone concealed AP ablation 8 years previously and bilateral circumferential pulmonary vein isolation (CPVI) 6 years previously. During regular electrocardiogram monitoring, it was suggested that irregular wide QRS tachycardia, which was considered to be atrial fibrillation with antegrade AP conduction, was the cause of the present symptoms. In the present electrophysiological study, we noticed a residual antegrade AP in the left lateral wall that was not observed during the previous session. We achieved abolition of overt accessory conduction, bilateral CPVI, and superior vena cava isolation with several radiofrequency applications without any recurrence. We also confirmed the absence of dormant conduction in the AP and the left atrium-PV connection with 20 mg adenosine triphosphate. This case demonstrated the possibility of sudden exposure of overt AP conduction late after catheter ablation of the concealed AP and the importance of confirming the absence of dormant conduction by means of adenosine triphosphate, which has the potential benefit of revealing latent AP conduction.

Cause of the "power-on reset" phenomenon other than electric magnetic interference in a patient with a pacemaker.

A 67-year old male with a dual-chamber pacemaker visited for a regular check-up. An unfamiliar message emerged on the display just after placing the programmer wand. We could recognize that the pacemaker had already been in the safe back-up mode of DDI, and the programmer prompted a re-initialization request. We are so surprised because there was no indication of device malfunction the day before in daily monitoring and a 12-lead electrocardiogram revealed normally working in the DDD mode just before checking the device. The pacemaker was immediately re-programmed to the former setting. This phenomenon has not recurred for 12 months.

Applicability of 3-Dimensional Quantitative Coronary Angiography-Derived Computed Fractional Flow Reserve for Intermediate Coronary Stenosis.

BACKGROUND: Quantitative flow ratio (QFR) is a newly developed image-based index for estimating fractional flow reserve (FFR).Methods and Results:We analyzed 151 coronary arteries with intermediate stenosis in 142 patients undergoing wire-based FFR measurement using dedicated software. Predefined contrast flow QFR, which was derived from 3-dimensional quantitative coronary angiography (3-D QCA) withThrombolysis in Myocardial Infarction (TIMI) frame counts, was compared with FFR as a reference. QFR had good correlation (r=0.80, P<0.0001) and agreement (mean difference: 0.01±0.05) with FFR. After applying the FFR cut-off ≤0.8, the overall accuracy rate of QFR ≤0.8 was 88.0%. On receiver operating characteristics analysis, the area under the curve was 0.93 for QFR. In contrast, 3-D QCA-derived anatomical indices had insufficient correlation with FFR and diagnostic performance compared with QFR. CONCLUSIONS: QFR had good correlation and agreement with FFR and high diagnostic performance in the evaluation of intermediate coronary stenosis, suggesting that QFR may be an alternative tool for estimating myocardial ischemia.

Left ventricular free wall perforation by a right ventricular pacemaker lead: a case report.

BACKGROUND: Lead perforation is one of the major complications of pacemaker implantation, but cases of right ventricular (RV) lead perforation through the septum and left ventricle are rarely reported. We described a rare case of left ventricular (LV) free wall perforation by an RV lead and the management of this complication. CASE SUMMARY: An 84-year-old man was admitted with a dual-chamber pacemaker due to pacing failure caused by an RV lead fracture. New lead implantation was performed on the next day, but pacing failure occurred again on the second post-operative day (POD). We found the lead perforation on the fluoroscopy during temporary pacemaker insertion. Computed tomography scan and transthoracic echocardiogram showed that the added lead perforated through both the septum and LV free wall. A new lead was inserted on the fourth POD, and an off-pump open chest surgery for extraction of the penetrating lead was performed uneventfully on the 20th POD. DISCUSSION: We considered that some features of the lead (SelectSecure 3830-69, Medtronic) may be related to this complication, as the lead was very thin, had a non-retractable bare screw and was inserted with a dedicated delivery catheter. We have to be careful when performing implantation of this kind of lead to avoid such a rare complication.

Applicability of quantitative flow ratio for rapid evaluation of intermediate coronary stenosis: comparison with instantaneous wave-free ratio in clinical practice.

Quantitative flow ratio (QFR) is an image-based fractional flow reserve (FFR) computed by three-dimensional quantitative coronary angiography and estimated flow velocity. Several studies have reported that QFR was rapidly computed within approximately 5 min and had a good diagnostic performance as compared with FFR. However, studies comparing QFR with instantaneous wave-free ratio (iFR) as an index with a prognostic value comparable to that of FFR are limited. Thus, we investigated the applicability of QFR with respect to iFR, both being easy-to-measure indices not requiring pharmacological hyperaemic induction. We computed QFR in prospectively enrolled 150 coronary lesions (including 50 lesions for onsite QFR analysis) in consecutive patients with intermediate stenosis evaluated by iFR. The correlation and diagnostic performance of QFR were compared using iFR as a reference. The mean QFR and iFR were 0.81 ± 0.12 and 0.89 ± 0.11, respectively. QFR and iFR exhibited a good correlation in all subjects (R = 0.70, p < 0.0001) and the onsite-analysed vessels (R = 0.74, p < 0.0001). In the receiver-operating characteristics analysis, the area under the curve of QFR predicting iFR ≤ 0.89 was 0.91. Applying the cut-off value of QFR ≤ 0.80 and iFR ≤ 0.89, the sensitivity, specificity, positive and negative predictive values were 85%, 83%, 72%, and 91%, respectively, in all subjects, and 82%, 82%, 78%, and 85%, respectively, in the onsite-analysed vessels. QFR including onsite analysis demonstrated a good correlation with iFR and a diagnostic performance comparable to that of iFR in consecutive patients with intermediate coronary stenosis, suggesting its potential as a rapidly derived index for evaluating myocardial ischaemia in clinical settings.

Successful elimination of premature ventricular contractions by ablation of origin and preferential pathway.

However, the common strategy for eliminating premature ventricular contractions (PVCs) is to explore the exit site and ablate, which may be difficult in some cases. The origin and the preferential pathway, an insulated pathway connected to the exit, may also become targets for eliminating PVCs.

Clinical Factors Relevant to the Recurrence of Atrial Tachyarrhythmia after Extensive Defragmentation Followed by Thoracic Vein Isolation.

INTRODUCTION: The efficacy of thoracic vein isolation (TVI), an approach to trigger atrial fibrillation (AF), for the management of AF has been established. Our goal was to identify the predictors for late recurrence of atrial tachyarrhythmias (ATAs), for which the patients and procedural and/or echocardiographic parameters were retrospectively analyzed. Although substrate modification in the atrium for the treatment of AF ablation remains controversial, the background associated with the outcome has not been fully investigated. We retrospectively studied 33 patients with paroxysmal AF and 21 with persistent AF undergoing defragmentation followed by TVI. We evaluated the late/early recurrences, defined as ATA at 3 months after/within the single procedure. METHODS AND RESULTS: During a median follow-up period of 22 (11-37) months, 28 patients (52%) experienced a late recurrence. There was a higher incidence of late recurrences in the patients with disease durations of ≥12.4 months, which was the optimal cut-off point measured in the receiver operating characteristic curve analysis, or in those with left atrial diameter >50 mm or with earlier recurrences than the others (19% versus 72%, p=0.01; 0% versus 37%, p=0.02; or 13% versus 53%, p<0.0001 by the log-rank test, respectively). Moreover, there was a trend toward a higher atrial tachycardia (AT)-free rate in the patients with AF termination during the procedure (75% versus 54%, p=0.07 by the log-rank test). A multivariate analysis based on the Cox proportional hazard model showed that disease duration ≥12.4 months or early recurrence was highly associated with the outcomes (HR 3.72, 95%CI 1.42-12.79, p<0.006; HR 4.80, 95%CI 2.24-10.56, p<0.0001). CONCLUSION: The AF duration and early ATA recurrence are the peri-procedural factors significantly relevant to the outcome after extensive defragmentation followed by TVI.

Interesting electrophysiological findings in a patient with coexistence of atrial tachycardia originating from coronary sinus and slow-fast atrioventricular nodal reentrant tachycardia.

Slow-fast atrioventricular nodal tachycardia (AVNRT) has various electrophysiological aspects due to atrioventricular (AV) nodal physiology. In addition, concomitantly another form of arrhythmia with AVNRT, especially atrial tachycardia (AT), was an infrequent arrhythmia. A 38-year-old female with narrow QRS tachycardia underwent electrophysiological study due to frequent faintness. The electrophysiological study disclosed the coexistence of AT originating from coronary sinus (CS) with slow-fast AVNRT. We easily diagnosed AT originating from CS and terminated with several radiofrequency ablations (RFA) around CS. The diagnosis of slow-fast AVNRT, however, was somewhat difficult due to the following findings: (1) small amount of adenosine triphosphate (ATP) could terminate slow-fast AVNRT reproducibly; (2) we could provoke slow-fast AVNRT only by RV pacing with isoproterenol infusion. With other electrophysiological findings, we diagnosed slow-fast AVNRT. Radiofrequency energy was delivered initially in the posteroseptal region, followed by inside CS, and finally in the middle septal region, which completed the slow pathway ablation. After the procedure, we could never provoke these arrhythmias. .

Focal right atrial tachycardia with three foci in a patient with polymyositis.

Cardiac involvement secondary to polymyositis is not infrequent. In addition, it sometimes presents various forms of arrhythmia, including atrial tachycardia (AT). A 72-year-old female who had 5-years history of polymyositis was referred to our clinic with symptomatic supraventricular tachycardia with 2:1 atrioventricular conduction. Electrophysiological study revealed a total of three focal AT in right atrium with the origin of the basal right atrial appendage (AT1), coronary sinus ostium (AT2), and low lateral right atrium (AT3), respectively. Endocardial bipolar voltage mapping showed low voltage area in the limited area, partially overlapping with the focus of AT3. We finally terminated AT2 targeting an early fractionated potential and AT3 at early activation site with a support of flexibly-bended deflectable sheath while accidentally eliminating AT3 with the bumping of a catheter. With the additional applications, we completely eliminated all AT. AT were never provoked by any inductions with isoproterenol infusion. .

Successful angioplasty with intravascular ultrasound and optical frequency domain imaging guidance for tandem intramural hematoma caused by coronary artery spasm.

A 39-year-old woman with no coronary risk factors was admitted due to repetitive morning chest pain. Coronary angiography revealed subtotal occlusion of the distal obtuse marginal branch that was not recanalized by intracoronary nitroglycerin administration. Intravascular ultrasound and optical frequency domain imaging showed tandem intramural hematomas in the culprit vessel. We performed cutting balloon angioplasty successfully with dual intracoronary imaging modality guidance. The 4-month follow-up angiography revealed favorable vascular healing and the provocation test induced multiple spasms, including in the culprit vessel, by intracoronary acetylcholine administration. .

Primary Multiple Cardiac Myxomas in a Patient without the Carney Complex.

Cardiac tumors are rare, and multiple myxomas are even rarer. The latter phenomenon is mostly associated with the Carney complex, a dominantly inherited disease characterized by multiple primary cardiac myxomas, endocrinopathy, and spotty pigmentation of the skin. We report the rare case of a patient who did not have the Carney complex but had multiple primary cardiac tumors. A 78-year-old woman with a past history of breast cancer was referred to our hospital for further examination of multiple cardiac tumors. Echocardiography showed 4 tumors in the left atrium and left ventricle. We could not diagnose them preoperatively and decided to resect them surgically because they were mobile and could have caused embolism and obstruction. The postoperative pathological findings of all 4 tumors were myxomas, although the patient did not meet the diagnostic criteria of the Carney complex. Therefore, a rare case of multiple primary cardiac myxomas was diagnosed.

Documented subacute stent thrombosis within thirty days after stenting with sirolimus-eluting stent (Cypher) for acute myocardial infarction: a Japanese single center retrospective non-randomized study.

BACKGROUND: The incidence of subacute stent thrombosis (SAT) within 30 days after stenting with a sirolimus-eluting stent (Cypher) for acute myocardial infarction (AMI) was retrospectively compared to that with bare-metal stents (BMS). METHODS AND RESULTS: Among 559 lesions in 558 consecutive AMI from April 2003 to February 2006, the incidence of documented SAT after Cypher implantation (2/276 lesions, 0.72%) was almost the same as for BMS (2 cases, 0.71%). Aspirin (81-100 mg/day) plus ticlopidine (200 mg/day) were administered continuously after admission in all 4 cases. CONCLUSION: Documented SAT did not increase after stenting with Cypher for AMI under aspirin plus ticlopidine.

Facilitation of rotablator-stenting by measuring angiographic lesion length with the navicath (type-MUTO), a new measuring microcatheter.

In the present study, the usefulness and feasibility of a new measuring microcatheter, the Navicath (Type-MUTO) microcatheter, for facilitating the stenting procedure subsequent to ablation using a rotablator (rota-stenting) is described. A method for measuring the length of the targeted lesion (lesion length) angiographically with the Navicath when exchanging the guide wires is presented using 2 representative cases of rota-stenting. In addition, the validity of the selected stent according to the measurement of lesion length with the Navicath was evaluated by comparing the length of the selected stent with lesion length before PCI measured by quantitative coronary angiography. Based on the results obtained, we believe the Navicath is useful for facilitating rota-stenting, and may even be applicable to PCI in general.

[Predictive value of coagulative molecular markers for thromboembolism in patients with nonvalvular atrial fibrillation: prospective five-year follow-up study].

OBJECTIVES: Nonvalvular atrial fibrillation is a known risk factor for thromboembolism. This study investigated the use of coagulation markers to predict thromboembolism in nonvalvular atrial fibrillation patients. METHODS: One hundred thirty nonvalvular atrial fibrillation patients (104 males, 26 females, mean age 63.7 +/- 10.7 years) treated at the Sendai Cardiovascular Center from April 1996 to August 1997 were enrolled in this study. Coagulation markers such as prothrombin fragment 1 + 2, thrombin-antithrombin III complex and D-dimer were measured, and the patients were followed up prospectively to October 2001. RESULTS: One hundred and twenty-six patents (100 males, 26 females, chase rate 96.9%) were included in this investigation based on the medical chart and telephone interview. During five-year follow-up, 16 patients had thromboembolism accidents (3.25%/year) and two were suspected to die of thromboembolism. Three patients died of malignant disease, four of heart disease, and five of other diseases. Eight (25.8%) of the 31 patients with high levels of thrombin-antithrombin III complex and 6 (33.3%) of 18 patients with high levels of D-dimer suffered thromboembolism accidents. High thrombin-antithrombin III complex and D-dimer were statistically positive predictive markers for thromboembolism in patients with nonvalvular atrial fibrillation (p < 0.05). CONCLUSIONS: Coagulation markers such as thrombin-antithrombin III complex and D-dimer can predict thromboembolism accidents in nonvalvular atrial fibrillation patients.

[Survivor of cardiogenic shock following acute myocardial infarction with Churg-Strauss syndrome: first angiographic documention of coronary recanalization of infarct-related arteries: a case report].

A 42-year-old man was treated under a diagnosis of Churg-Strauss syndrome with predonisolone pulse therapy. Three days later, he developed cardiogenic shock following acute myocardial infarction. Coronary angiography showed total occlusions in three peripheral coronary vessels. Intraaortic balloon pumping was used to maintain hemodynamics and predonisolone pulse therapy was repeated. However, he developed cardiogenic shock again after the second pulse therapy and needed percutaneous cardiopulmonary support and intraaortic balloon pumping. Accordingly, combination therapy of predonisolone and cyclophosphamide was given. He then recovered. Follow-up angiography showed recanalization of the infarct-related arteries.