Electrophysiological evidence of right atrial epicardial connections in a case with recurrent common atrial flutter.

The majority of the cavotricuspid isthmus (CTI) region consists of discretely arranged muscle bundles separated by connective tissue. Heterogeneity in the anatomic arrangement of the muscle bundles results in differences in the endocardial and epicardial activation patterns. We present a case of recurrent atrial flutter (AFL) despite the presence of a complete endocardial CTI block. We found epicardial-endocardial breakthrough (EEB) sites on the right atrial high septum. In addition, the epicardial excitation confirmed by endocardial activation mapping was detected as far-field potentials. Radiofrequency ablation was performed at the EEB site. No AFL has recurred for 12 months after the present procedure.

Significance of mitral L-waves in predicting late recurrences of atrial fibrillation after radiofrequency catheter ablation.

BACKGROUND: The mitral L-wave, a prominent mid-diastolic filling wave in echocardiographic examinations, is associated with severe left ventricular diastolic dysfunction. The relationship between the mitral L-wave and outcome of catheter ablation (CA) in patients with atrial fibrillation (AF) has not been established. This study aimed to evaluate the predictive value of mitral L-waves on AF recurrence after CA. METHODS: This was a retrospective and observational study in a single center. One hundred forty-six patients (mean age; 63.9 [56.0-72.0] years, 71.9% male) including 66 non-paroxysmal AF patients (45.2%) who received a first CA were enrolled. The mitral L-waves were defined as a distinct mid-diastolic flow velocity with a peak velocity ≥20 cm/s following the E wave in the echocardiographic examinations before CA. The patients enrolled were divided into groups with (n = 31, 21.2%) and without (n = 115, 78.8%) mitral L-waves. Univariate and multivariate analyses were carried out to determine the predictive factors of late recurrences of AF (LRAFs), which meant AF recurrence later than 3 months after the CA. RESULTS: During a follow-up of 28.8 (15.0-35.8) months, the ratio of LRAFs in patients with mitral L-waves was significantly higher than that in those without mitral L-waves (15 [46.9%] vs. 16 [14.0%], p < .001). A multivariate analysis using a Cox proportional hazard model revealed that the mitral L-waves were a significant predictive factor of LRAFs (hazard ratio: 3.09, 95% confidence interval: 1.53-6.24, p = .002). CONCLUSION: The appearance of mitral L-waves could predict LRAFs after CA.

The inducibility and focus of atrial fibrillation after ablation in patients with tachycardia-induced heart failure.

BACKGROUND: The inducibility of atrial fibrillation (AF) and incidence of nonpulmonary vein (nonPV) triggers in patients with heart failure (HF) have not been elucidated. Furthermore, the relationship between AF triggers and the change in the left ventricular (LV) function after catheter ablation (CA) remains unclear. METHODS: A total of 101 consecutive patients with a history of HF due to tachycardia who underwent CA of AF were prospectively enrolled (64.8 ± 10.7 years, male 72.3%, and paroxysmal AF 15.8%). According to the AF inducibility by isoproterenol (ISP), the patients were divided into two groups: inducible AF (66.3%) and noninducible AF (33.7%). Furthermore, inducible AF was categorized into a PV type (61.2%) and nonPV type (38.8%). This study investigated the AF recurrence and change in the LV ejection fraction (LVEF) after CA. RESULTS: AF recurred in 35 patients (34.7%) during the follow-up period (41.6 ± 26.8 months). Kaplan-Meier curves showed that patients with noninducible AF had just as bad an AF recurrence rate as those with the nonPV type. Cox proportional hazards models also revealed that noninducible AF (Hazard-ratio, 5.74; 95% CI, 1.81-18.13) was associated with a higher risk of recurrence. The LVEF significantly improved after the CA (from 49.1 ± 16.3% to 67.0 ± 7.9%). However, the nonPV type was associated with a lower improvement in the LVEF (Odds-ratio, 0.18; 95% CI, 0.05-0.70). CONCLUSION: The AF inducibility was associated with AF recurrence. Furthermore, the nonPV triggers were associated with a lesser improvement in the LVEF. Confirming the AF inducibility and triggers was important to predict the outcome after CA.

Predictive value of the cardio-ankle vascular index for recurrence of atrial fibrillation after catheter ablation.

BACKGROUND: The predictive value of the cardio-ankle vascular index (CAVI) for estimating the efficacy outcome of catheter ablation (CA) in atrial fibrillation (AF) patients is unclear. We aimed to examine the predictive performance of the CAVI for recurrences of atrial arrhythmias after CA. METHODS: We enrolled a total of 193 patients with AF (paroxysmal 126 and non-paroxysmal 67) who underwent initial CA procedures at our institute, and CAVI measurements were conducted between January 2016 and March 2017. We evaluated recurrences of atrial arrhythmias after the first CA procedure as a clinical outcome. The CAVI value was assessed and the enrolled patients were divided according to the optimal CAVI value cut-off point (9.5) in the atrial arrhythmia recurrence group. RESULTS: During a mean follow-up of 31.3 (17.5-43.0) months, 74 (32.5%; PaAF 41 and 49.3%; non-PaAF 33) patients had recurrences of atrial arrhythmias. The recurrence ratio of atrial arrhythmias was significantly higher in patients with a high CAVI (≥9.5) than those with a low CAVI (<9.5) (log rank test; p = 0.018). A univariate analysis showed the association between higher CAVI values and recurrences of atrial arrhythmias (p = 0.072). Multivariate analyses using a Cox proportional hazard model after adjusting for other clinical factors revealed that the CAVI value was determined to be a significant predictive factor of a recurrence of atrial arrhythmias after CA (Hazard ratio: 1.44, 95% confidence interval: 1.17-1.78, p < 0.01). CONCLUSIONS: The CAVI was significantly associated with a recurrence of atrial arrhythmias after CA in AF patients.

Role of Intracardiac Defibrillation During the Ablation Procedure as a Predictor of Atrial Fibrillation Recurrence After Catheter Ablation.

Intracardiac defibrillation (IDF) is performed to restore sinus rhythm (SR) during radiofrequency catheter ablation (RFCA) of atrial fibrillation (AF). This study aimed to investigate the change in the IDF threshold before and after RFCA during the ablation procedure and determine whether the IDF threshold after RFCA was associated with the AF substrate and AF recurrence. A total of 141 consecutive patients with drug-refractory persistent AF (age 62.5 ± 10.3 years, 84.4% male) were enrolled in this study. Before RFCA, we initially performed IDF with an output of 1 J. When IDF failed to restore SR, the output was gradually increased to 30 J. After RFCA, we attempted pacing-induced AF to provoke other focuses of AF. When AF was induced, we performed IDF again to terminate AF with outputs of 1 to 30 J. The change in the IDF threshold to restore SR before and after RFCA was evaluated. After RFCA, the IDF threshold for restoring SR significantly decreased (from 11.5 ± 8.6 J to 4.0 ± 3.8 J, P < 0.001). During the follow-up (24.3 ± 12.2 months), SR was maintained in 107 patients (75.9%). The multivariate analysis using a Cox proportional-hazards model revealed that an IDF threshold of > 5 J after RFCA was significantly associated with the AF recurrence (HR, 3.99; 95% confidence interval 1.93-8.22; P = 0.0001). RFCA decreased the IDF threshold for restoring SR in patients with persistent AF. The IDF output of > 5 J after RFCA could be a predictor of AF recurrence independent of the AF substrate.

Comparison of Landiolol and Digoxin as an Intravenous Drug for Controlling the Heart Rate in Patients with Atrial Fibrillation and Severely Depressed Left Ventricular Function.

Clinical experience with landiolol use in patients with atrial fibrillation (AF) and a severely depressed left ventricular (LV) function is limited. We compared the efficacy and safety of landiolol with that of digoxin as an intravenous drug in controlling the heart rate (HR) during AF associated with a very low LV ejection fraction (LVEF).We retrospectively analyzed 53 patients treated with landiolol (n = 34) or digoxin (n = 19) for AF tachycardias with an LVEF ≤ 25. The landiolol dose was adjusted between 0.5 and 10 µg/kg/minute according to the patient's condition. The response to treatment was defined as a decrease in the HR of ≤ 110/minute, and that decreased by ≥ 20% from baseline.There were no significant differences between the two groups regarding the clinical characteristics. The responder rate to landiolol at 24 hours was significantly higher than that to digoxin (71.0% versus 41.2%; odds ratio: 4.65, 95% confidence interval: 1.47-31.0, P = 0.048). The percent decrease in the HR from baseline at 1, 2, 12, and 24 hours was greater in the landiolol group than in the digoxin group (P < 0.01, P = 0.071, P = 0.036, and P = 0.016, respectively). The systolic blood pressure (SBP) from baseline within 24 hours after administering landiolol was significantly reduced, whereas digoxin did not decrease the SBP over time. Hypotension (< 80 mmHg) occurred in two patients in the landiolol group and 0 in the digoxin group (P = 0.53).Landiolol could be more effective in controlling the AF HR than digoxin even in patients with severely depressed LV function. However, careful hemodynamic monitoring is necessary when administering landiolol.

Clinical Factors Associated with a Successful Catheter Ablation Outcome in Elderly Patients with Atrial Fibrillation.

Catheter ablation is currently an established treatment for symptomatic paroxysmal atrial fibrillation (AF). We focused on elderly patients with a high prevalence of AF and attempted to identify the clinical factors associated with unsuccessful ablation outcomes.Among 735 consecutive patients who underwent AF ablation procedures, 108 (14.7%, 66 men) aged ≥ 75 years were included. Of them, 80 had paroxysmal AF, and the remaining 28 non-paroxysmal AF. All patients underwent pulmonary vein (PV) isolation and occasionally additional ablation. When AF recurred, redo ablation procedures were performed if the patient so desired.The mean number of ablation procedures was 1.1 ± 0.4 times per patient. During a mean follow-up of 38.7 ± 21.7 months, sinus rhythm was maintained in 100 patients (92.6%) without any antiarrhythmic drugs, but not in the remaining 8 (7.4%). Left atrial diameter (LAD, P < 0.001), left ventricular (LV) systolic diameter (P < 0.001), LV diastolic diameter (P = 0.001), non-PV AF foci (P = 0.036), and diabetes (P = 0.045) were associated with unsuccessful ablation procedures. Multivariate logistic regression analysis revealed a large LAD and non-PV AF foci were significant independent predictors of AF recurrences, with odds ratios of 0.76 (P = 0.019) and 0.04 (P = 0.023), respectively. In a total of 124 procedures, one major (0.8%) and 11 minor (8.9%) complications occurred.In elderly AF patients, catheter ablation of AF is effective and safe. Non-PV AF foci and a large LAD were independent clinical predictors of unsuccessful AF ablation outcomes.

Comparison of the Transdermal Bisoprolol Patch with Oral Bisoprolol Fumarate Administration as a Therapeutic Agent for Idiopathic Frequent Premature Ventricular Contractions.

The transdermal bisoprolol patch (TB) was designed to maintain a sustained concentration of bisoprolol in plasma by a higher trough concentration than oral bisoporolol (OB). We compared the efficacy between TB and OB in patients with idiopathic premature ventricular contractions (PVCs) while considering their duration of action.A total of 78 patients with a PVC count of ≥ 3,000 beats/24 hours were divided into groups treated with TB 4 mg (n = 43) or OB 2.5 mg (n = 35). PVCs were divided into positive heart rate (HR) -dependent PVCs (P-PVCs) and non-positive HR-dependent PVCs (NP-PVCs) based on the relationship between the hourly PVC density and hourly mean HR. Twenty-four-hour Holter electrocardiograms were performed before and 1 to 3 months after the initiation of therapy.There were no significant between-group differences in the baseline characteristics. Both the TB (from 14.6 [9.9-19.2] to 7.6 [1.7-15.8]%, P < 0.001) and OB (from 13.2 [7.6-21.9] to 4.6 [0.5-17.0]%, P = 0.0041) significantly decreased the PVC density, and there was no significant difference between the two groups (P = 0.73). Compared to OB, the TB had similar effects in reducing the PVC density for P-PVCs (P = 0.96), and NP-PVCs (P = 0.71). The TB significantly decreased the P-PVC density from baseline not only during day-time (P < 0.001) but also night-time (P = 0.0017), while the OB did not significantly decrease the P-PVC density from baseline during night-time (P = 0.17).Compared to OB, the TB could be used with the same efficacy of reducing idiopathic PVCs. The TB may be a more useful therapeutic agent than OB for P-PVCs during a 24-hour period.

The relationship between serum indoxyl sulfate and the renal function after catheter ablation of atrial fibrillation in patients with mild renal dysfunction.

Indoxyl sulfate (IS), a protein-bound uremic toxin, induces renal disorders and atrial fibrillation (AF). It is well known that renal dysfunction is a risk factor for AF and radiofrequency catheter ablation (RFCA) improves the renal function. However, the improvement in the renal function after RFCA in patients with early stage chronic kidney disease (CKD) and the serial changes in the IS level have not been fully elucidated. This study aimed to investigate whether IS affects the improvement in the renal function. A total of 91 consecutive patients with mild kidney dysfunction (CKD stage I-II) who underwent RFCA and maintained sinus rhythm were prospectively enrolled. The plasma IS level and estimated glomerular filtration rate (eGFR) were determined before, 3 months, and 1 year after RFCA. The patients were divided according to the IS quartiles (Q1-4; < 0.4, 0.4-0.7, 0.7-1.2, and > 1.2 µg/ml). There was no significant difference in the eGFR among the IS quartiles. A significantly higher eGFR improvement rate was obtained for IS-Q4 than the other quartiles (p = 0.039). The IS-Q4 IS level significantly decreased at 1 year after RFCA (1.8 ± 0.8 to 1.2 ± 0.7 µg/ml, p < 0.01). The multivariable logistic model revealed that a high-IS level (IS-Q4) was an independent predictor of an eGFR improvement (OR 3.33; 95% CI 1.16-9.59; p = 0.026). A high-IS level reduction after RFCA improved the renal function in AF patients with mild kidney dysfunction.

Right Ventricular Septal Pacing Using a Thin Lumenless Pacing Lead and Delivery System with a Deflectable Catheter.

The SelectSecure™ lead system (SSLS), which is composed of a thin lumenless, active-fixation lead and a deflectable catheter, is approved for use in Japan. This study aimed to evaluate the long-term clinical outcomes of right ventricular (RV) septal pacing with the SSLS along with the system's safety and electrical performance. A total of 129 patients were divided into the following 3 groups: the RV septal pacing with the SSLS group (SSP, n = 21); the RV septal pacing with the conventional lead group (Septal, n = 77); and the RV apical pacing with the conventional lead group (Apical, n = 31). All lead-related complications and pacing parameters during follow-up were compared among the groups. The clinical outcome was heart failure-associated hospitalization. The SSP and Septal groups showed significantly shorter paced QRS duration than the Apical group. During the follow-up for a mean of 49.5 ± 13.1 months, no lead-related complications occurred in any of the groups. A case of pericardial effusion occurred in the SSP group, but cardiac tamponade did not occur, and it spontaneously resolved. The ventricular pacing threshold after the follow-up period was higher in the SSP group than in the other 2 groups. There was no difference in the primary heart failure hospitalization among the 3 groups. The SSLS could be effective in producing a narrow QRS width with RV septal pacing, but its pacing threshold was higher than conventional leads in the chronic phase.

Obesity Is Associated With the Development of Interstitial Pneumonia Under Long-Term Administration of Amiodarone in Refractory Atrial Fibrillation Patients.

Although oral amiodarone (AMD) has been used for the management of atrial fibrillation (AF), serious complications such as interstitial pneumonia (IP) occur very occasionally. We evaluated which factors were associated with the development of IP under the long-term administration of AMD in patients with refractory AF.This study included 122 consecutive patients (65.8 ± 11.4 years, mean body mass index [BMI] of 23.2 ± 4.3 kg/m(2)) who orally received AMD to inhibit AF between January 2004 and December 2013. Administration of AMD was begun at 400 mg daily as a loading dose, and was continued at a dosage of 50-400 mg daily after the initial loading phase, determined by the control of the arrhythmias and occurrence of side-effects. The clinical factors were compared between the patients with and without adverse effects, especially IP.During an average follow-up period of 49.2 ± 28.2 months, 53 patients (43.4%) were determined to have converted and maintained sinus rhythm. In contrast, adverse effects were detected in 46 patients (37.7%) with AMD. IP occurred in 8 patients (6.6%), thyrotoxicosis in 35 (28.7%), and others in 5 (4.1%). Four (50.0%) out of 8 patients complicated with IP had obesity (BMI > 27 kg/m(2)). Among the clinical factors, only obesity was significantly associated with the development of IP (P = 0.026).In patients with refractory AF, AMD had an antiarrhythmic effect with long-term administration, but greater adverse effects were also observed. Obesity was the most significant factor associated with the development of IP.

Successful Left Atrial Posterior Wall Isolation Including Roof Line Ablation Using a Cryoballoon for Persistent Atrial Fibrillation with Dextrocardia and Situs Inversus.

Cryoballoon ablation has been established as an effective method for pulmonary vein isolation and has recently been investigated for its efficacy of substrate modification on the left atrial roof area in patients with persistent atrial fibrillation. We herein report the first successful case of left atrial posterior wall isolation including roof line ablation using cryoballoons in a patient with persistent atrial fibrillation, dextrocardia, and situs inversus. Cryoballoon ablation proved to be a safe and straightforward approach to create lasting lesions along the left atrial roof line and left atrial posterior wall, even under challenging anatomical conditions.

Impact of Atrial Fibrillation Triggers on Long-Term Outcomes of a Second Catheter Ablation of Nonparoxysmal Atrial Fibrillation.

Background: Catheter ablation (CA) of atrial fibrillation (AF) triggers, including non-pulmonary vein (PV) foci, contributes to improved procedural outcomes. However, the clinical significance of an AF trigger ablation during second CA procedures for nonparoxysmal AF is unknown. Methods and Results: We enrolled 94 patients with nonparoxysmal AF undergoing a second CA. Intracardiac cardioversion during AF using high-dose isoproterenol was performed to determine the presence or absence of AF triggers. PV re-isolations were performed if PV potentials recurred, and if AF triggers appeared from any non-PV sites, additional ablation was added to those sites. We investigated the incidence of atrial arrhythmia recurrence (AAR) >3 months post-CA. Of the 94 enrolled patients, AF triggers were identified in 65 (69.1%), and of those with AF triggers, successful elimination of the triggers was achieved in 47 patients (72.3%). Multivariate analysis revealed that no observed AF triggers were a significant predictor of AAR (hazard ratio [HR] 1.97, 95% confidence interval [CI] 1.21-3.46, P=0.019). In a subanalysis of the patients with AF triggers, multivariate analysis showed that unsuccessful trigger ablation was significantly associated with AAR (HR 5.84, 95% CI 2.79-12.22, P<0.01). Conclusions: Having no observed AF triggers during a second CA session significantly increased the risk of AAR, as did unsuccessful CA of AF triggers.

A case of constrictive pericarditis with a milk of calcium pericardial effusion undergoing surgical treatment.

Milk of calcium (MOC) pericardial effusion (PE) is extremely rare and has rarely been reported. A 78-year-old man was referred to our institution because of breathlessness and bilateral leg edema. Echocardiography revealed mild PE. In addition, abrupt posterior motion of the ventricular septum in early diastole was observed. A non-contrast chest computed tomography revealed a hyperdense PE, with Hounsfield units of 130, suggestive of MOC PE. Right heart catheterization (RHC) revealed that the right ventricular pressure had a dip and plateau pattern. We diagnosed the patient with constrictive pericarditis (CP) with MOC PE. As the right heart failure secondary to CP was refractory to medical therapy, we decided to perform surgical treatment. During pericardiectomy, a highly viscous PE, of which the color was pale and reddish brown, was aspirated. Chemical analysis of the PE revealed a very high calcium content of 39.2 mmol/L. The clinical symptoms secondary to CP improved. RHC performed postoperatively confirmed the disappearance of a dip and plateau pattern in the right ventricular pressure. In conclusion, we experienced a of CP with MOC PE and surgical treatment contributed to the improvement of the clinical symptoms and pericardial constriction secondary to CP. Learning objective: Because constrictive pericarditis (CP) with milk of calcium (MOC) pericardial effusion (PE) can cause severe morbidity and even mortality, the early diagnosis of CP is important in patients suspected of having MOC PE. MOC PE has hyperdensity on computed tomography, so its findings could be helpful in the diagnosis of MOC PE. Pericardiectomy for CP with MOC PE may contribute to the improvement of the clinical symptoms and pericardial constriction secondary to CP.

Myocarditis Following a COVID-19 Messenger RNA Vaccination: A Japanese Case Series.

COVID-19 vaccine-related myocarditis has been reported worldwide. We herein report two Japanese cases with suspected vaccine-related myocarditis. A 27-year-old man was admitted with chest pain 4 days after the second vaccination. An electrocardiogram (ECG) did not reveal any significant abnormalities. The second patient, a 37-year-old man, was admitted with chest pain 9 days after the first vaccination. His ECG exhibited ST-elevation in multiple leads. In both cases, cardiac magnetic resonance imaging findings were consistent with myocarditis. They recovered with symptomatic relief within a few days. These cases suggest that the benefit of COVID-19 vaccination exceeds the risk of vaccine-related myocarditis.

Relationship between the degree of renal dysfunction and the safety and efficacy outcomes in patients with atrial fibrillation receiving direct oral anticoagulants.

BACKGROUND: The clinical evaluation of a direct oral anticoagulant (DOAC) treatment for atrial fibrillation (AF) patients with renal dysfunction has not been sufficiently studied. This study aimed to evaluate the safety and efficacy of DOACs for patients with a severely impaired renal function. METHODS: This was a retrospective and observational study in a single center. We enrolled 894 consecutive AF patients who were prescribed DOACs, and divided them into three groups based on their creatinine clearance (CrCl) value: CrCl ≥ 50 mL/min group (n = 634), CrCl 30-49 mL/min group (n = 207), and CrCl 15-29 mL/min group (n = 53). We evaluated the occurrence of major bleeding (MB) as the safety outcome and thromboembolic events (TEs) as the efficacy outcome during the follow-up. RESULTS: The incidence of MB in the CrCl 15-29 mL/min group was significantly higher than in the other groups (CrCl ≥ 50 mL/min group, 0.8/100 person-years; CrCl 30-49 mL/min group, 1.2/100 person-years; CrCl 15-29 mL/min group, 9.0/100 person-years, log rank test, P < .001). On the other hand, there was no significant difference in the incidence of TEs among the three groups. A multivariate analysis using a Cox proportional hazard model adjusted for the age revealed that the CrCl 15-29 mL/min group was significantly associated with increased MB compared to the CrCl ≥ 50 mL/min group (hazard ratio: 9.76, 95% confidence interval: 2.69-35.5, P < .001). Similar results were observed when adjusting for other multiple clinical factors. CONCLUSION: This study demonstrated that the degree of renal dysfunction was a significant prognostic factor for MB in AF patients receiving DOACs.

Relationship between the nutritional status and safety and efficacy outcomes in atrial fibrillation patients aged 80 years and over receiving oral anticoagulants.

BACKGROUND: Malnutrition has been reported to be associated with worse clinical outcomes in various cardiovascular diseases. We aimed to investigate the clinical significance of the nutritional status in atrial fibrillation (AF) patients aged 80 years and over receiving oral anticoagulants (OACs), focusing on the difference between direct OACs (DOACs) and warfarin treatment. METHODS: This was a retrospective and observational study. We enrolled 332 consecutive AF patients aged 80 years and over who were treated with OACs: DOACs (n = 256) and warfarin (n = 76). A controlling nutritional status (CONUT) score was used to evaluate the nutritional status. The enrolled patients were divided into two groups based on the CONUT score: CONUT score <5 (n = 239) and CONUT score ≥5 (n = 93) groups. We investigated the relationship between the nutritional status and clinical outcomes. RESULTS: The CONUT score ≥5 group had significantly higher incidence of major bleeding (MB) compared to the CONUT score <5 group (4.6/100 person-years vs. 0.7/100 person-years, p < 0.01). On Cox hazard analysis, CONUT score ≥5 group was significantly associated with increased MB compared with the CONUT score <5 group (hazard ratio: 5.80, 95% confidence interval: 1.44-23.33, p = 0.013). In the DOAC group, the incidence of MB did not differ between the CONUT score ≥5 and CONUT score <5 groups (p = 0.54). In the warfarin group, MB occurred more frequently in the CONUT score ≥5 group than CONUT score <5 group (p < 0.01). There was no significant difference in the incidence of thromboembolic events between the CONUT score ≥5 and CONUT score <5 groups in both the DOAC and warfarin groups. CONCLUSIONS: The prognostic values of the nutritional status based on the CONUT score for MB differed between AF patients aged 80 years and over receiving DOACs and those receiving warfarin. It may be favorable to use DOACs to avoid bleeding events in those with malnutrition.

Early electrocardiographic indices for predicting chronic doxorubicin-induced cardiotoxicity.

BACKGROUND: Dealing with chemotherapy-related cardiac dysfunction (CTRCD) remains a significant problem complicated by the difficulty in early detection of cardiotoxicity. Electrocardiogram (ECG) is expected to be the most realistic methodology due to lower cost-performance and non-invasiveness. We investigated the long-term visual fluctuations in the ECG waveforms in patients with chronic doxorubicin (DOX)-induced cardiotoxicity to identify ECG indices for the early detection of cardiotoxicity. METHODS: We conducted a retrospective case series study by reviewing the medical records of 470 consecutive patients with malignant lymphoma who were treated with DOX at our institute between January 2010 and December 2017. Of them, 23 (4.9%) patients developed left ventricular dysfunction and were diagnosed with CTRCD using echocardiography. We assessed the ECG indices on 12-lead ECG recordings before and after treatment in 15 patients; eight patients were excluded due to conduction disturbances or atrial fibrillation. RESULTS: CTRCD was detected at a median of 475 (interquartile range, IQR: 341-1333) days after initiating chemotherapy. The evaluation of ECG indices preceding CTRCD development was performed 93 (IQR: 52-232) days before the detection of CTRCD. In the stage of CTRCD, the most significant ECG change was T-wave flattening in leads V3-V6 (12 patients, 80%). Additionally, QTa prolongation was observed in leads I and aVL (n = 10, 66%), leads II, III, and aVF (n = 9, 60%), and leads V3-V6 (n = 10, 73%). These ECG changes were not observed before the treatment but were detected mildly in the pre-CTRCD stage, which subsequently worsened in the CTRCD stage. CONCLUSIONS: This study indicated that T-wave changes and QTa prolongation may be useful as an early indicator before the onset of CTRCD in patients with DOX-induced cardiotoxicity.

The Difference in the Changes of Indoxyl Sulfate after Catheter Ablation among Atrial Fibrillation Patients with and without Kidney Dysfunction.

Indoxyl sulfate (IS), a protein-bound uremic toxin, induces chronic kidney disease (CKD) and atrial fibrillation (AF). Catheter ablation (CA) of AF improves the renal function. However, the transition of uremic toxins is unclear. This study aimed to investigate the transition of the serum IS level in AF patients with and without CKD after CA. A total of 138 consecutive AF patients who underwent CA and maintained sinus rhythm were prospectively enrolled (paroxysmal AF 67.4%). The patients were divided into 4 groups (non-CKD/low-IS:68, non-CKD/high-IS:28, CKD/low-IS:13, and CKD/high-IS:29). The plasma IS levels and estimated glomerular filtration rate (eGFR) were determined before and 1-year after CA. CKD was defined as CKD stage III and a high-IS according to the mean IS (IS ≥ 1.1 µg/ml). CA significantly improved the eGFR in CKD patients (p < 0.001). The serum IS level in the non-CKD/high-IS group was significantly decreased (from 1.7 ± 0.7 to 1.1 ± 0.6 µg/ml, p < 0.001). However, the serum IS level in the CKD/high-IS group did not improve (from 1.9 ± 0.9 to 1.7 ± 0.7 µg/ml, p = 0.22). The change in the IS in the CKD patients significantly differed from that in those without CKD. In the CKD patients, CA did not significantly decrease the IS, a risk factor of CKD, regardless of an improved eGFR.

Transient, Marked ST-Segment Elevation During Successful Epicardial Substrate Ablation in a Patient With Brugada Syndrome.

A 37-year-old man with Brugada syndrome and frequent appropriate implantable cardioverter-defibrillator shocks received an epicardial substrate ablation. During the procedure to eliminate delayed potentials, transient, marked ST-segment elevation in lead V2 was observed, particularly in the anterior right ventricle with a borderline between normal and low-voltage areas. (Level of Difficulty: Intermediate.).