Activation pattern of the coronary sinus facilitates the differentiation for ventricular outflow tract arrhythmias.

INTRODUCTION: The accuracy of surface ECG algorithms for predicting the origin of outflow tract ventricular arrhythmias (OT-VAs) might be questioned. Intracardiac electrograms recorded at anatomic landmarks could provide new predictive insights. We aim to evaluate the efficacy of a novel criterion utilizing the activation pattern of the coronary sinus (CS) in localizing OT-VAs, including VAs originating from the right ventricular outflow tract (RVOT), endocardial left ventricular outflow tract (Endo-LVOT), and epicardial left ventricular outflow tract (Epi-LVOT). METHODS: We measured the ventricular activation time of the mitral annulus (MA) from the onset of the earliest QRS complex of VAs to the initial deflection over the isoelectric line at local signals, namely the QRS-MA interval. The activation at 3 and 12 o'clock of the MA was recorded as the QRS-MA3 and QRS-MA12 intervals, respectively. Their predictive values were compared to previous ECG algorithms. RESULTS: A total of 68 patients with OT-VAs were enrolled (51 for development and 17 for validation). From early to late, the ventricular activation sequences at MA12 were as follows: Epi-LVOT, Endo-LVOT, and RVOT. In LBBB morphology OT-VAs, the QRS-MA12 interval was significantly earlier for LVOT origins than RVOT origins. In the combined cohort of development and validation cohort, a cut-off value of ≤10 ms predicted the LVOT origin with a sensitivity of 100% and specificity of 78%. The QRS-MA12 interval ≤ -24 ms additionally predicted epicardial LVOT sites of origin. CONCLUSIONS: The QRS-MA interval could accurately differentiate the OT-VAs localization.

Angiographic assessment of vein of Marshall in atrial fibrillation: Implications for identification and cannulation.

Background: The vein of Marshall (VOM) ethanol infusion improves rhythm control in atrial fibrillation (AF). The identification and cannulation of the VOM can be technically challenging. This study aimed to assess the angiographic morphology of the VOM and investigate its value in the VOM ethanol infusion. Methods: Patients with AF (n = 162) scheduled for combined catheter ablation and VOM ethanol infusion were enrolled. The VOM morphologic features in the right anterior oblique (RAO), the left anterior oblique (LAO), and the LAO cranial views were analyzed. The impact of morphology on the identification and cannulation of the VOM was investigated. Results: The VOM was identified in 159 (98.1 %) and cannulated in 150 (92.6 %) patients. The VOM identification rate in the RAO and LAO/LAO cranial view was 97.3 % and 89.3 %, respectively. Of 134 patients with VOM identification in the LAO/LAO cranial view, 104 (77.6 %) had a VOM ostium clock location (VOMoClock) of ≤3 and 3-4 o'clock. The VOM cannulation success rate in the ≤3, 3-4, 4-5, and 5-6 o'clock groups was 100 %, 92.6 %, 88.5 %, and 77.8 %, respectively (p = 0.032). The median (interquartile range) cannulation time in the four groups was 10.5 (6.3), 12.0 (9.0), 13.0 (23.0), and 34.0 (30.0) minutes, respectively (p < 0.001). The diameter of the coronary sinus ostium in the RAO view and the VOMoClock were independent predictors for difficult cannulation. Conclusions: The VOM morphologic features in different angiographic views provide valuable information which could facilitate the identification and cannulation of the VOM.

Double-wire technique to facilitate vein of Marshall cannulation and ethanol infusion in atrial fibrillation: a case series.

BACKGROUND: The vein of Marshall (VOM) ethanol infusion is increasingly performed in combination with catheter ablation in atrial fibrillation (AF). The cannulation of the VOM can sometimes be challenging. This study aimed to evaluate the double-wire technique in cases of difficult cannulation of the VOM. CASE PRESENTATION: Patients with AF scheduled for combined catheter ablation and VOM ethanol infusion were consecutively enrolled. The procedure was performed via the femoral vein. If the regular cannulation technique with one angioplasty wire failed or took more than 20 min, the double-wire technique using a stabilizing wire and a cannulation wire was performed. The unique technique was used mainly in two scenarios, when the Eustachian ridge was too prominent as a barrier for catheter manipulation or when the VOM ostium was close to the coronary sinus ostium. Of 162 patients scheduled for VOM ethanol infusion, the double-wire technique was applied in 6 (3.7%) patients and led to a 100% successful cannulation rate of the VOM. Of the six patients, two had a prominent Eustachian ridge, and four had a VOM ostium close to the coronary sinus ostium. The mean cannulation time was 33.3 ± 7.3 min. The ethanol infusion was successfully performed in 5 patients. One patient had a collateral circulation in the distal VOM, and ethanol infusion was not performed. CONCLUSIONS: The double-wire technique can facilitate VOM cannulation and ethanol infusion in challenging cases. WORD COUNT: 231.

Noninvasive assessment of myocardial work during left ventricular isovolumic relaxation in patients with diastolic dysfunction.

BACKGROUND: This study aims to investigate the value of myocardial work (MW) parameters during the isovolumic relaxation (IVR) period in patients with left ventricular diastolic dysfunction (LVDD). METHODS: This study prospectively recruited 448 patients with risks for LVDD and 95 healthy subjects. An additional 42 patients with invasive measurements of left ventricular (LV) diastolic function were prospectively included. The MW parameters during IVR were noninvasively measured using EchoPAC. RESULTS: The total myocardial work during IVR (MWIVR), myocardial constructive work during IVR (MCWIVR), myocardial wasted work during IVR (MWWIVR), and myocardial work efficiency during IVR (MWEIVR) of these patients were 122.5 ± 60.1 mmHg%, 85.7 ± 47.8 mmHg%, 36.7 ± 30.6 mmHg%, and 69.4 ± 17.8%, respectively. The MW during IVR was significantly different between patients and healthy subjects. For patients, MWEIVR and MCWIVR were significantly correlated with the LV E/e' ratio and left atrial volume index, MWEIVR exhibited a significant correlation with the maximal rate of decrease in LV pressure (dp/dt per min) and tau, and the MWEIVR corrected by IVRT also exhibited a significant correlation with tau. CONCLUSIONS: MW during IVR significantly changes in patients with risks for LVDD, and is correlated to LV conventional diastolic indices, including dp/dt min and tau. Noninvasive MW during IVR may be a promising tool to evaluate the LV diastolic function.

Occluding morphologically complicated left atrial appendage using the small-umbrella LAmbre device.

BACKGROUND: Percutaneous left atrial appendage (LAA) occlusion is effective for stroke prevention in patients with atrial fibrillation. LAA can have a complex anatomy, such as multiple lobes or a large orifice, which may render it unsuitable for occlusion using regular devices. We aimed to investigate the feasibility, safety, and short-term efficacy of the small-umbrella LAmbre device for morphologically complicated LAA. METHODS: We retrospectively enrolled 129 consecutive patients who underwent LAA occlusion using the LAmbre device; the small-umbrella LAmbre device was used in 30 of these patients. We analyzed patients' characteristics, procedural details, and outcomes. RESULTS: Twenty-two patients (73.3%) had multilobed (≥ 2) LAA. The umbrella of the occluder was anchored in the branch in 9 patients and in the common trunks of branches in 13 patients. The landing zone and orifice diameters were 19.0 ± 4.39 mm and 27.4 ± 3.95 mm, respectively. The sizes of the umbrella and occluder cover were 22.0 ± 3.42 mm and 34.3 ± 2.75 mm, respectively. At 3-month follow-up transesophageal echocardiography in 24 patients, no peri-device residual flow was reported. Device thrombosis was detected in one patient at 3 months and disappeared after 3 months of anticoagulation. Ischemic stroke occurred in one patient; no other adverse events were reported. CONCLUSIONS: Occlusion of morphologically complicated LAA using the small-umbrella LAmbre device was feasible, safe, and effective in patients with atrial fibrillation in this study. This occluder provides an alternative for patients who cannot be treated with regular-sized LAA occlusion devices.

Characteristics and Long-Term Ablation Outcomes of Supraventricular Arrhythmias in Hypertrophic Cardiomyopathy: A 10-Year, Single-Center Experience.

Background: A variety of supraventricular arrhythmias (SVAs) may occur in patients with hypertrophic cardiomyopathy (HCM). The characteristics and long-term ablation outcomes of different types of SVAs in HCM have not been comprehensively investigated. Methods: We retrospectively enrolled 101 consecutive patients with HCM who were referred to the electrophysiology and arrhythmia service from May 2010 to October 2020. The clinical features and ablation outcomes were analyzed. Results: Seventy-eight patients had SVAs, which comprised 50 (64.1%) cases of atrial fibrillation (AF), 16 (20.5%) of atrial flutter (AFL), 15 (19.2%) of atrioventricular reentrant tachycardia (AVRT), 11 (14.1%) of atrial arrhythmia (AT), and 3 (3.8%) of atrioventricular nodal reentrant tachycardia (AVNRT). Thirty-four patients underwent catheter ablation and were followed up for a median (interquartile range) of 58.5 (82.9) months. There was no recurrence in patients with non-AF SVAs. In patients with AF, the 1- and 7-year AF-free survival rates were 87.5 and 49.5%, respectively. A receiver operator characteristic analysis showed that a greater left ventricular end-diastolic dimension (LVEDD) was associated with a higher recurrence of AF, with an optimum cutoff value of 47 mm (c-statistic = 0.91, p = 0.011, sensitivity = 1.00, specificity = 0.82). In Kaplan-Meier analysis, patients with a LVEDD ≥ 47 mm had worse AF-free survival than those with a LVEDD <47 mm (log-rank p = 0.014). Conclusions: In this unique population of HCM, AF was the most common SVA, followed in order by AFL, AVRT, AT, and AVNRT. The long-term catheter ablation outcome for non-AF SVAs in HCM is satisfactory. A greater LVEDD predicts AF recurrence after catheter ablation in patients with HCM.

Radiofrequency Catheter Ablation of Supraventricular Tachycardia in Patients With Pulmonary Hypertension: Feasibility and Long-Term Outcome.

BACKGROUND: Supraventricular tachycardia (SVT) occurs commonly and is strongly correlated with clinical deterioration in patients with pulmonary hypertension (PH). This study aimed to investigate the feasibility and long-term outcome of radiofrequency catheter ablation (RFCA) in PH patients with SVT. MATERIALS AND METHODS: Consecutive PH patients with SVT who were scheduled to undergo electrophysiological study and RFCA between September 2010 and July 2019 were included. The acute results and long-term success of RFCA were assessed after the procedure. RESULTS: In total, 71 PH patients with 76 episodes of SVT were analyzed. Cavotricuspid isthmus-dependent atrial flutter (n = 33, 43.5%) was the most common SVT type, followed by atrioventricular nodal reentrant tachycardia (n = 16, 21.1%). Of the 71 patients, 60 (84.5%) underwent successful electrophysiological study and were subsequently treated by RFCA. Among them, acute sinus rhythm was restored in 54 (90.0%) patients, and procedure-related complications were observed in 4 (6.7%) patients. Univariate logistic regression analysis showed that cavotricuspid isthmus-independent atrial flutter [odds ratio (OR) 25.00, 95% confidence interval (CI) 3.45-180.98, p = 0.001] and wider pulmonary artery diameter (OR 1.19, 95% CI 1.03-1.38; p = 0.016) were associated with RFCA failure. During a median follow-up of 36 (range, 3-108) months, 7 patients with atrial flutter experienced recurrence, yielding a 78.3% 3-year success rate for RFCA treatment. CONCLUSION: The findings suggest that RFCA of SVT in PH patients is feasible and has a good long-term success rate. Cavotricuspid isthmus-independent atrial flutter and a wider PAD could increase the risk for ablation failure.

Association of maximum standardized uptake value with occult mediastinal lymph node metastases in cN0 non-small cell lung cancer.

OBJECTIVES: The management of non-small cell lung cancer (NSCLC) relies on the tumour-node-metastasis (TNM) stage, and the treatment regimen differs based on the N status. Positron emission tomography-computed tomography (PET-CT) has emerged as a powerful imaging tool for the detection of various cancers with a relatively low false-negative rate. We explored predictors to identify false-negative N2 disease in PET-CT. METHODS: A total of 284 consecutive cN0 patients with peripheral NSCLC who underwent PET-CT scans followed by curative intent resections were enrolled as a training set to identify predictors of occult N2 metastases by multivariable analysis. The accuracy and cut-off values for the predictors were calculated using a receiver operating characteristic curve. Clinical and pathological data were analysed retrospectively. An additional 151 patients were collected as a test set to validate the results, including the occult N2 rate and accuracy. RESULTS: In total, 8.5% (24/284) PET-CT-diagnosed N0 NSCLC cases had pathologically diagnosed N2 metastases. The SUVmax of the primary tumour was a unique independent risk factor for occult N2 NSCLC [P = 0.003, 95% confidence interval = 0.81-0.96, odds ratio (OR) = 0.88]. Occult N2 metastases occurred more frequently in the subcarinal (16/24) and right lower paratracheal lymph nodes (12/24). Accordingly, we divided the patients into two groups by SUVmax: the occult N2 rates in the SUVmax of <2.6 and SUVmax of ≥2.6 groups were 1.0% (1/100) and 12.5% (23/184), respectively (P = 0.001). In the test set, the occult N2 incidence rate was 9.3% (14/151), with the highest rates occurring in the subcarinal (9/14) and right lower paratracheal lymph nodes (6/14). In the two groups defined by SUVmax, the occult N2 rates were 4% (2/50) and 11.9% (12/101), respectively. CONCLUSIONS: The SUVmax of the primary tumour was an independent risk factor for occult N2 metastases in NSCLC patients diagnosed as clinical N0 by PET-CT. SUVmax of ≥2.6 of the primary tumour may indicate the risk of N2 metastases, and invasive mediastinal staging techniques or comprehensive therapy should not be ignored in these patients.