Importance of Preoperative Computed Tomography Assessment of the Membranous Septal Anatomy in Patients Undergoing Transcatheter Aortic Valve Replacement With a Balloon-Expandable Valve.

BACKGROUND: Cardiac conduction disturbance (CD) is the most frequent complication following transcatheter aortic valve replacement (TAVR). This study examined whether the anatomy of the membranous septum (MS) could provide useful information about the risk of CD following TAVR with a balloon-expandable valve (BEV).Methods and Results:Among 132 consecutive patients, 106 (mean age, 85.6±5.1 years; 75 females) were included in the study. Using preoperative CT and angiography, MS length and implantation depth (ID) were assessed. The MS length minus the prosthesis ID was calculated (∆MSID). Correlation between CD, defined as new-onset left-bundle branch block (LBBB) or the need for permanent pacemaker (PPM) within 1 week after the procedure, and MS length were evaluated. A total of 19 patients (18%) developed CD following TAVR. MS length was significantly shorter in these patients than in those without CD (5.3±1.3 vs. 6.6±1.4; P<0.001), and was the important predictor of CD (odds ratio [OR]: 0.43, 95% confidence interval [CI]: 0.27-0.69, P<0.001). When considering the pre- and postprocedural parameters, the ∆MSID was smaller in patients with CD (-1.7±1.5 vs. 0.8±1.9, P<0.001), and emerged as the important predictor of CD (OR: 0.47, 95% CI: 0.33-0.69, P<0.001). CONCLUSIONS: Short MS is associated with an increased risk of CD after TAVR with BEV.

Clinical significance of rectus femoris diameter in heart failure patients.

Heart failure (HF) is often accompanied by skeletal muscle weakness and exercise intolerance, which are known as prognostic factors of HF. Comprehensive evaluation of physical function is important, but it is not commonly conducted because of the lack of equipment or appropriate expertise. Measurement of rectus femoris diameter (RFD) by ultrasound is convenient and noninvasive, but it has not been clarified that RFD could represent physical functions in HF patients. This study evaluated 185 consecutive HF patients and underwent assessment including RFD, grip power (GP), knee extension strength (KES), skeletal muscle index (SMI), nutrition status, cardiopulmonary exercise testing, and New York Heart Association (NYHA) functional class. RFD was related with NYHA class and significantly correlated with GP, KES, SMI, body mass index, pre-albumin level, geriatric nutritional risk index, and peak VO2 (r = 0.631, 0.676, 0.510, 0.568, 0.380, 0.539, 0.527, respectively; p < 0.001). Multivariate regression analysis revealed that estimated glomerular filtration rate (ß = 0.551) and RFD (ß = 0.326) were predictive factors of peak VO2. Gender, age, brain natriuretic peptide level, left ventricular ejection fraction, and hemoglobin level were the other explanatory parameters. The cut off value of RFD for sarcopenia diagnosis was estimated as 15 mm (sensitivity = 0.767 and specificity = 0.808). RFD is a simple and useful marker which reflects skeletal muscle strength/volume, exercise tolerance, nutrition status, and NYHA class. It is also associated with sarcopenia in HF patients.

Pauses in atrial rhythm in a patient with limb-girdle muscular dystrophy: A case report.

A 58-year-old woman with a history of multi-origin atrial tachycardia and limb-girdle muscular dystrophy was treated for presyncope caused by pauses in atrial rhythm. A dual-chamber pacemaker was implanted. The low-voltage area extended broadly, but 10-V pacing could not capture the large right atrium, including the right atrial appendage, except the coronary sinus ostium. The atrial lead was screwed in using a steerable stylet. A ventricular lead was placed in the right ventricular apex. Atrial pacing at the coronary sinus was required to treat the pauses in the atrial rhythm.

Angioscopic Evaluation During Balloon Pulmonary Angioplasty in Chronic Thromboembolic Pulmonary Hypertension.

BACKGROUND: Chronic thromboembolic pulmonary hypertension (CTEPH) is a progressive disorder with a poor prognosis. Recently, balloon pulmonary angioplasty (BPA) has been reported to be an effective treatment for inoperable patients with CTEPH. However, this catheter-based treatment has potentially life-threatening vascular complications. To improve the efficacy and safety of BPA, we assessed the morphological evaluation of organised thrombus and the vascular injury by BPA procedure. METHODS: In this study, we assessed the morphology of organised thrombi and the vascular injury observed by angioscopy during BPA in 28 lesions from nine CTEPH patients. RESULTS: Angioscopy visualised various forms of organised thrombi such as 'Mesh', 'Slit', 'Flap' and 'Mass' and allowed for a detailed evaluation of organised thrombus that was difficult to do by conventional contrast angiography. In addition, after balloon dilation for BPA, angioscopy revealed a haemorrhage due to a vessel wall injury caused by wiring and/or ballooning. CONCLUSIONS: Assessment of organised thrombus and vascular injury by angioscopy might contribute to improving the treatment of the patients with CTEPH.

Brachial-Ankle Pulse Waves Reflect the Hemodynamics of Valvular Heart Disease.

BACKGROUND: Brachial-ankle pulse wave (ba-PW) analysis is an established technique for assessing arterial stiffness and cardiovascular risk. The peripheral arterial pulse wave configuration may be useful for valvular heart disease (VHD) detection because it is closely related to the physical signs of VHD; however, few reports have been made assessing the efficacy of ba-PW analysis for VHD screening. METHODS: Consecutive VHD patients scheduled for valve surgery were enrolled in the study. These included 58 patients with aortic stenosis (AS) (mean age 74 ± 1.1 years), 67 with aortic regurgitation (AR) (mean age 59 ± 1.9 years), and 65 with mitral regurgitation (MR) (mean age 62 ± 1.6 years). Ba-PW analysis was conducted using the VaSera VS-1500 screening system before and after surgery. Upstroke time (UT), ejection time (ET), pre-ejection period (PEP), PEP/ET ratio, mean arterial pressure (%MAP), and cardio-ankle vascular index (CAVI) were compared with a control group (n = 65; mean age 69 ± 1.5 years) without VHD. RESULTS: The UT was significantly shorter in the AR group (132.9 ± 4.0 ms) and MR group (134.5 ± 2.5 ms), but significantly longer in the AS group (178.2 ± 2.8 ms) compared to controls (149.6 ± 3.6 ms; all p <0.01). The ET was significantly longer in the AS group (318.5 ± 7.4 ms) and AR group (320.0 ± 4.6 ms), but significantly shorter in the MR group (289.0 ± 3.8 ms) compared to controls (305.3 ± 3.4 ms; all p <0.05). In ROC analyses of each group compared to controls, areas under the curve of UT, corrected (c)UT, ET and cET in the AS group, UT/ET ratio in the AR group, and PEP/UT ratio in the MR group were all >0.7. CONCLUSIONS: Multiple pulse wave parameters reflect VHD hemodynamics and may be useful for screening for the condition.

Impact of Door-to-Balloon Time in Patients With ST-Elevation Myocardial Infarction Who Arrived by Self-Transport　- Acute Myocardial Infarction-Kyoto Multi-Center Risk Study Group.

BACKGROUND: Patients with ST-elevation myocardial infarction (STEMI) who arrive at a hospital via self-transport reportedly have a delayed door-to-balloon time (DBT). However, the clinical impacts of delayed DBT on in-hospital mortality among such patients are not well known.Methods and Results:In total, 1,172 STEMI patients who underwent primary percutaneous coronary intervention between January 2009 and December 2013 from the Acute Myocardial Infarction (AMI) Kyoto Registry were analyzed. Compared with the emergency medical service (EMS) group (n=804), the self-transport group (n=368) was younger and had a significantly longer DBT (115 min vs. 90 min, P<0.01), with fewer patients having a Killip classification of 2 or higher. The in-hospital mortality rate was lower in the self-transport group than in the EMS group (3.3% vs. 7.1%, P<0.01). A DBT >90 min was an independent predictor of in-hospital mortality in EMS patients (odds ratio (OR)=2.43, P=0.01) but not in self-transport patients (OR=0.89, P=0.87). CONCLUSIONS: The present study demonstrated that there was no relationship between in-hospital prognosis and DBT ≤90 min in STEMI patients using self-transport. The prognosis of these patients cannot be improved by focusing only on DBT. Treatment strategies based on means of transport should also be considered.

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.

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.

Relationship Between Mean Blood Pressure at Admission and In-Hospital Outcome After Primary Percutaneous Coronary Intervention for Acute Myocardial Infarction.

A J-shaped or U-shaped curve phenomenon might exist between systolic blood pressure (SBP) or pulse pressure (PP) at admission and in-hospital mortality in Japanese patients with acute myocardial infarction (AMI) undergoing primary percutaneous coronary intervention (PCI). However, data regarding a relationship between mean blood pressure (MBP) at admission and in-hospital outcome in AMI patients undergoing primary PCI are still lacking in Japan.A total of 1,413 primary PCI-treated AMI patients were classified into quintiles based on admission MBP (< 79 n = 283, 79-91 n = 285, 92-103 n = 285, 104-115 n = 279, and ≥ 116 mmHg n = 281). Patients with MBP < 79 mmHg had a significantly higher in-hospital mortality, while mortality was not significantly different among the other quintiles: 16.6% (< 79), 4.9% (79-91), 3.9% (92-103), 3.2% (104-115), and 5.0% (≥ 116 mmHg). On multivariate analysis, Killip class ≥ 3 at admission, LMT or multivessels as culprit lesions, admission MBP < 79 mmHg, and age were independent positive predictors of in-hospital mortality, whereas hypercholesterolemia and TIMI 3 flow before/after PCI were negative predictors, while the other MBP categories were not.These results suggest that admission MBP < 79 mmHg might be associated with in-hospital death, and the in-hospital prognostic effects of MBP, the steady component of blood pressure, at admission might be different from those of SBP or PP, the pulsatile component of blood pressure, at admission in Japanese AMI patients undergoing primary PCI.

A protective role of Nox1/NADPH oxidase in a mouse model with hypoxia-induced bradycardia.

Although it has been reported that endotoxin-induced expression of Nox1 in the heart contributes to apoptosis in cardiomyocytes, functional role of Nox1 at the physiological expression level has not been elucidated. The aim of this study was to clarify the role of Nox1 under a hypoxic condition using wild-type (WT, Nox1(+/Y)) and Nox1-deficient (Nox1(-/Y)) mice. ECG recordings from anesthetized mice revealed that Nox1(-/Y) mice were more sensitive to hypoxia, resulting in bradycardia, compared to WT mice. Atrial and ventricular electrocardiograms recorded from Langendorff-perfused hearts revealed that hypoxic perfusion more rapidly decreased heart rate in Nox1(-/Y) hearts compared with WT hearts. Sinus node recovery times measured under a hypoxic condition were prolonged more markedly in the Nox1(-/Y) hearts. Sinoatrial node dysfunction of Nox1(-/Y) hearts during hypoxia was ameriolated by the pre-treatment with the Ca(2+) channel blocker nifedipine or the K(+) channel opener pinacidil. Spontaneous action potentials were recorded from enzymatically-isolated sinoatrial node (SAN) cells under a hypoxic condition. There was no significant difference in the elapsed times from the commencement of hypoxia to asystole between WT and Nox1(-/Y) SAN cells. These findings suggest that Nox1 may have a protective effect against hypoxia-induced SAN dysfunction.

Prognostic impact of chronic kidney disease and anemia at admission on in-hospital outcomes after primary percutaneous coronary intervention for acute myocardial infarction.

Cardiorenal anemia syndrome has recently been receiving greater attention; however, data regarding the relationship between chronic kidney disease (CKD)/anemia on presentation and in-hospital outcome in patients with acute myocardial infarction (AMI) undergoing primary percutaneous coronary intervention (PCI) are still limited in Japan.A total of 1,447 primary PCI-treated AMI patients were classified into 4 groups according to the presence of CKD and/or anemia on hospital admission (with CKD/with anemia n = 222, with CKD/without anemia n = 299, without CKD/with anemia n = 151, without CKD/without anemia n = 775). Angiographic acute results of primary PCI were similar among the 4 groups. The patients with CKD had a significantly higher in-hospital overall mortality rate than the patients without CKD, and in the presence or absence of CKD, patients with anemia tended to have a higher in-hospital mortality rate than the patients without anemia. According to a multivariate analysis, anemia on admission was found to be an independent predictor of in-hospital mortality, whereas admission CKD and admission eGFR were statistically not independent predictors. Moreover, the multivariable adjusted odds ratio of in-hospital death in AMI patients with CKD alone was 1.855 (95% CI 0.929-3.706), and that in AMI patients with CKD/with anemia was 3.384 (95% CI 1.697-6.748).These results suggest that among real-world, unselected Japanese AMI patients undergoing primary PCI, the combination of CKD and anemia on admission confers significant adverse effects on in-hospital mortality.

Prognostic impact of pulse pressure at admission on in-hospital outcome after primary percutaneous coronary intervention for acute myocardial infarction.

Data regarding relationship between pulse pressure (PP) at admission and in-hospital outcome in patients with acute myocardial infarction (AMI) undergoing primary percutaneous coronary intervention (PCI) are still lacking. A total of 1413 primary PCI-treated AMI patients were classified into quintiles based on admission PP (<40, n = 280; 40-48, n = 276; 49-57, n = 288; 58-70, n = 288; and ≥71 mmHg, n = 281). The patients with PP < 40 mmHg tended to have higher prevalence of male, smoking, and Killip class ≥3 at admission; right coronary artery, left main trunk (LMT), or multivessels as culprit lesions; larger number of diseased vessels; lower Thrombolysis in Myocardial Infarction (TIMI) grade in the infarct-related artery before/after primary PCI; and higher value of peak creatine phosphokinase concentration. Patients with PP < 40 mmHg had highest mortality, while patients with PP 49-57 mmHg had the lowest: 11.8 % (<40), 7.2 % (40-48), 2.8 % (49-57), 5.9 % (58-70), and 6.0 % (≥71 mmHg). On multivariate analysis, Killip class ≥3 at admission, LMT or multivessels as culprit lesions, chronic kidney disease, and age were the independent positive predictors of the in-hospital mortality, whereas admission PP 49-57 mmHg, hypercholesterolemia, and TIMI 3 flow before/after PCI were the negative ones, but admission PP < 40 mmHg was not. These results suggest that admission PP 49-57 mmHg might be correlated with better in-hospital prognosis in Japanese AMI patients undergoing primary PCI.

Klotho is associated with VEGF receptor-2 and the transient receptor potential canonical-1 Ca2+ channel to maintain endothelial integrity.

Klotho is a circulating protein, and Klotho deficiency disturbs endothelial integrity, but the molecular mechanism is not fully clarified. We report that vascular endothelium in Klotho-deficient mice showed hyperpermeability with increased apoptosis and down-regulation of vascular endothelial (VE)-cadherin because of an increase in VEGF-mediated internal calcium concentration ([Ca(2+)]i) influx and hyperactivation of Ca(2+)-dependent proteases. Immunohistochemical analysis, the pull-down assay using Klotho-fixed agarose, and FRET confocal imaging confirmed that Klotho protein binds directly to VEGF receptor 2 (VEGFR-2) and endothelial, transient-receptor potential canonical Ca(2+) channel 1 (TRPC-1) and strengthens the association to promote their cointernalization. An in vitro mutagenesis study revealed that the second hydrolase domain of Klotho interacts with sixth and seventh Ig domains of VEGFR-2 and the third extracellular loop of TRPC-1. In Klotho-deficient endothelial cells, VEGF-mediated internalization of the VEGFR-2/TRPC-1 complex was impaired, and surface TRPC-1 expression increased 2.2-fold; these effects were reversed by supplementation of Klotho protein. VEGF-mediated elevation of [Ca(2+)]i was sustained at higher levels in an extracellular Ca(2+)-dependent manner, and normalization of TRCP-1 expression restored the abnormal [Ca(2+)]i handling. These findings provide evidence that Klotho protein is associated with VEGFR-2/TRPC-1 in causing cointernalization, thus regulating TRPC-1-mediated Ca(2+) entry to maintain endothelial integrity.

Atrial flutter after surgeries of congenitally corrected transposition of great arteries in total visceral inversion.

A 51-year-old man, who had a history of open heart surgery for corrected transposition of great arteries, presented with palpitation due to atrial tachycardia. A propagation map using three-dimensional electroanatomical mapping (CARTO3) showed atrial flutter and underwent linear ablation successfully. This case highlights the difficulty of diagnosis before mapping following a complicated cardiac operation and the usefulness of three-dimensional mapping.

A case of cardiac tamponade due to coronary artery injury caused by atrial screw-in lead.

A 74-year-old man who had a history of paroxysmal atrial fibrillation, visited the emergency department because of syncope. An electrocardiogram showed atrial fibrillation with slow ventricular response and long pauses. A permanent pacemaker was implanted under oral anticoagulation. Two screw-in leads were positioned at the right atrial appendage and the right ventricular apex. Seven hours after the implantation, he collapsed with hypotension due to cardiac tamponade. Vital signs improved after urgent pericardial drainage, but blood was continuously drained from the pericardial catheter. Due to uncontrollable cardiac tamponade, surgical repair was indicated. We found neither of the leads perforated the myocardium, but there was intermittent bleeding from a pin hole injury in the atrial wall site of the right coronary artery. Redness was observed in the right atrial appendage, but there was no bleeding point. We supposed that the screw tip of the atrial lead might have perforated the atrial appendage,　but was retracted spontaneously afterwards. The pin hole was closed with a patch and the postoperative course was uneventful. This is a rare case of cardiac tamponade due to the injury of the coronary artery by a screw-in lead positioned at the right atrial appendage. .

Favorable changes of left ventricular function in the circumferential direction following transcatheter atrial septal defect closure: a strain imaging study.

To clarify the impact on left ventricular (LV) function of percutaneous atrial septal defect (ASD) closure in adult patients. Echocardiograms of 46 patients (52 ± 18 years) who underwent ASD closure with a significant left-to-right shunt obtained before and 1 month after the procedure were retrospectively analyzed. Functional parameters were obtained by 2-dimensional speckle-tracking imaging. Global longitudinal strain and strain rate at early diastole (SRe) was calculated from the three standard apical views, while circumferential and radial parameters were calculated from basal, middle, and apical LV short-axis views. Along with a diminished right ventricular (RV) volume, the LV volume and ejection fraction increased (end-diastolic volume: 61 ± 12 to 76 ± 15 mL, p < 0.001; and 63% ± 4 to 64% ± 4% p = 0.03; respectively). Both global strain and SRe was augmented only in the circumferential direction (- 16.2% ± 2.9% to - 19.8% ± 2.8%; and 1.07 ± 0.29 to 1.34 ± 0.28 s-1, both p < 0.001). Augmentation of circumferential SRe correlated with both the changes in and the pre-procedural value of diastolic LV eccentricity index (r = - 0.57, p < 0.001; and r = 0.37, p = 0.01; respectively), a morphological parameter of RV volume overload. Following ASD closure in adults, both LV systolic and diastolic function could favorably change in the circumferential direction, and the degree of diastolic functional change is associated with RV volume overload, i.e., severity of ventricular interdependence.

The association between late-phase early recurrence within the blanking period after atrial fibrillation catheter ablation and long-term recurrence: Insights from a large-scale multicenter study.

BACKGROUND: The relationship between the timing of the first early recurrence and late recurrence after a single catheter ablation procedure for atrial fibrillation is controversial. METHODS: The Efficacy of Short-Term Use of Antiarrhythmic Drugs After Catheter Ablation for Atrial Fibrillation trial followed 2038 patients who underwent radiofrequency catheter ablation for atrial fibrillation. RESULTS: Of the patients, 907 (45%) had early recurrences within 90 days after the initial ablation. We divided these patients into two groups according to the timing of the first early recurrence episode, namely the ER1 group (early recurrence during the early phase; 0-30 days, n = 814) and ER2 group (early recurrence during the late phase; 31-90 days, n = 93). Three years after ablation, patients with early recurrences had a significantly lower event-free rate from late recurrences after a 90-day blanking period than patients without early recurrences (36.2% and 74.2%, respectively; log-rank, P < 0.0001). Three years after ablation, the event-free rate was significantly higher in the ER1 than the ER2 group (38.3% and 17.1%, respectively; log-rank, P < 0.0001). Moreover, the event-free rate at 3 years in the ER2 group was extremely low (5.6%) in patient with non-paroxysmal atrial fibrillation. CONCLUSION: Early recurrences were strongly associated with late recurrences, especially in patients with the first recurrence episode at >1 month within the blanking period after a single ablation procedure. Therefore, these patients should undergo close observation during follow-up, when they had especially with non-paroxysmal atrial fibrillation.

Tachycardiomyopathy Caused by a Pseudo-Ventricular Tachycardia: The Role of Imaging and Ablation in Diagnosis and Treatment.

A 50-year-old man presented with general fatigue on exertion. Investigations revealed tachycardia-induced cardiomyopathy induced by Wolff-Parkinson-White syndrome and atrial fibrillation. He was successfully treated with catheter ablation. Cardiac magnetic resonance imaging revealed that delayed enhancement throughout the left ventricle disappeared within 2 months after ablation. (Level of Difficulty: Beginner.).

Subcutaneous implantable cardioverter-defibrillator was inappropriate for use in a patient with aborted sudden cardiac death due to coronary spastic angina: a case report.

BACKGROUND: Implantable cardioverter-defibrillator (ICD) is recommended for secondary prevention in patients with coronary spastic angina and aborted sudden cardiac death. The effectiveness of subcutaneous ICD (S-ICD) for patients with coronary artery spastic angina is controversial. CASE SUMMARY: A 54-year-old man presented with ventricular fibrillation. Emergent coronary angiography showed diffuse narrowing of the coronary arteries that was reversible with isosorbide dinitrate. He was diagnosed with coronary spastic angina. S-ICD was implanted after the administration of a calcium-channel blocker and nicorandil. Seven months after the implantation, he collapsed again due to sinus node dysfunction and atrioventricular block caused by cardiac ischaemia. He developed cardiac arrest at both admissions. Six hours after the admission, electrocardiogram showed transient right bundle branch block. Inappropriate shocks were delivered because of low R-wave amplitude and T-wave oversense. S-ICD was replaced with a transvenous device in order to manage these two arrhythmias and inappropriate shocks. DISCUSSION: Patients with coronary artery spasm and aborted sudden cardiac death are candidates for implantation of S-ICD, but there are risks of bradycardia and inappropriate shocks in other ischaemic events.

Improvement in Exercise Tolerance after Catheter Ablation for Premature Ventricular Complexes: A Case Report.

BACKGROUND: Recent reports on catheter ablation for premature ventricular complex (PVC) or ventricular tachycardia in the context of cardiomyopathy suggest that ablation can improve cardiac function and decrease the number of PVCs. However, reports on exercise tolerance after catheter ablation for PVC are few. CASE: A 56-year-old woman consulted her primary care doctor presenting with palpitations and fatigue on exertion. Her left ventricular systolic function had been normalized with medications after a diagnosis of dilated cardiomyopathy 5 years previously. Electrocardiography showed sinus rhythm and ventricular bigeminy. Holter electrocardiography revealed a total of 34,867 PVCs. The highest number of consecutive PVCs recorded was three. In the cardiopulmonary exercise test, the peak oxygen consumption (VO2) was markedly reduced to 14 ml/kg/min. The patient was referred to our hospital for catheter ablation because pharmacotherapy was ineffective. PVCs originated from the left ventricular outflow tract and were successfully eliminated by ablation at the non-coronary cusp of the aortic valve using three-dimensional activation mapping with a CARTO system. The patient's symptoms on exertion improved immediately after ablation. Postoperative Holter electrocardiography revealed that the number of PVCs had decreased to one per day. Peak VO2 had markedly improved to 22 ml/kg/min 2 months after catheter ablation therapy. DISCUSSION: The elimination of frequent PVCs contributed to improved exercise tolerance.