Difference in radiofrequency ablation profile between during sinus rhythm and atrial fibrillation: Considerations in this era of high-power short-duration strategy.

Background: The concept of ablation index (AI) was introduced to evaluate radiofrequency (RF) ablation lesions. It is calculated from power, contact force (CF), and RF duration. However, other factors may also affect the quality of ablation lesions. To examine the difference in RF lesions made during sinus rhythm (SR) and atrial fibrillation (AF). Methods: Sixty patients underwent index pulmonary vein isolation during SR (n = 30, SR group) or AF (n = 30, AF group). All ablations were performed with a power of 50 W, a targeted CF of 5-15 g, and AI of 400-450 using Thermocool Smarttouch SF. The CF, AI, RF duration, temperature rise (Δtemp), impedance drop (Δimp), and the CF stability of each ablation point quantified as the standard deviation of the CF (CF-SD) were compared between the two groups. Results: A total of 3579 ablation points were analyzed, which included 1618 and 1961 points in the SR and the AF groups, respectively. Power, average CF, RF duration per point, and the resultant AI (389 ± 59 vs. 388 ± 57) were similar for the two rhythms. However, differences were seen in the CF-SD (3.5 ± 2.2 vs. 3.8 ± 2.1 g, p < .01), Δtemp (3.8 ± 1.3 vs. 4.0 ± 1.3°C, p < .005), and Δimp (10.3 ± 5.8 vs. 9.4 ± 5.4 Ω, p < .005). Conclusions: Despite similar AI, various RF parameters differed according to the underlying atrial rhythm. Ablation delivered during SR demonstrated less CF variability and temperature increase and greater impedance drop than during AF.

Conduction time around the mitral valve annulus has the potential to rule out postablation perimitral atrial tachycardia.

INTRODUCTION: It would be helpful in determining ablation strategy if the occurrence of perimitral atrial tachycardia (PMAT) could be predicted in advance. We investigated whether estimated perimitral conduction time (E-PMCT), namely, twice the time between coronary sinus (CS) pacing and the ensuing wave-front collision at the opposite side of the mitral annulus, correlated with the cycle length of PMAT and could predict future PMAT. METHODS AND RESULTS: We retrospectively (retrospective cohort) and prospectively (validation cohort) investigated atrial fibrillation patients who had received pulmonary vein isolation (PVI) and in whom left atrial maps had been created during CS pacing. We calculated their E-PMCT. PMAT was observed either by provocation or during follow-up in 25, AT other than PMAT was observed in 24 (non-PMAT AT group), and 53 patients never displayed any AT (no-AT group) in the retrospective cohort. In the PMAT group of the retrospective cohort, a strong positive correlation was observed between the PMAT CL and E-PMCT (r = .85, p < 0.001). PMAT was never induced nor observed in patients with E-PMCT less than 176 ms, and the best cut-off value for PMAT was 180 ms by receiver-operating characteristic curve analysis. In the validation cohort of 76 patients, the cut-off value of the E-PMAT less than 180 ms predicted noninducibility of PMAT, with a sensitivity of 78.6%, specificity of 100%, positive predictive value of 100%, and negative predictive value of 25.0%. CONCLUSION: Short E-PMCT may predict noninducibility of PMAT and guide a less invasive ablation strategy.

Diuretic and renal effects of angiotensin receptor-neprilysin inhibitor in patients hospitalized for acute heart failure.

In patients hospitalized for acute decompensation of heart failure (HF), the impact of angiotensin receptor-neprilysin inhibitor (ARNI) on diuresis and renal function has not been fully investigated. Patients with HF and reduced ejection fraction who were hospitalized for acute decompensation and newly initiated ARNI after hemodynamic stabilization were enrolled. Changes in urine volume (UV), body weight, estimated glomerular filtration rate (eGFR), and urine N-acetyl-beta-d-glucosaminidase (uNAG) levels before and after ARNI initiation were investigated. Changes in the diuretic response [DR, calculated as urine volume/(intravenous furosemide volume/40 mg)], N-terminal pro-brain natriuretic peptide (NT-proBNP), hematocrit, and plasma volume (PV) were also evaluated. A total of 60 patients were enrolled. ARNI was initiated at a median of 6 [5, 7] days after hospitalization. After initiation of ARNI, body weight, NT-proBNP, and PV decreased. UV and DR increased only on the day of ARNI initiation (delta UV 400 ± 957 ml and delta DR 1100 ± 3107 ml/40 mg furosemide) and then decreased to baseline levels. In the multivariable linear regression analysis, younger age, higher BMI, and higher NT-proBNP levels were significantly associated with greater UV after ARNI initiation. eGFR and uNAG did not significantly change after the initiation of ARNI [delta eGFR -1.7 ± 12.0 mL/min/1.73 m2 and delta uNAG 2.0 (-5.6, 6.9) IU/L]. In patients hospitalized for HF, the initiation of ARNI was associated with a small and transient increase in UV and DR, and was not associated with worsening of renal function or tubular injury.

Anticoagulant management during percutaneous coronary intervention for a patient with antithrombin deficiency.

Previous reports on cardiac intervention in cases with antithrombin deficiency are extremely limited. We report a case of acute coronary syndrome with antithrombin deficiency in a 62-year-old man with multiple histories of thrombosis. He had worsening chest pain, and laboratory data showed an elevated level of troponin T, suggesting acute myocardial infarction. Currently, there is no fixed anticoagulation strategy for coronary intervention in patients with antithrombin deficiency. In this case, we performed coronary intervention with heparin in addition to antithrombin concentrate. The intervention was successfully performed without thrombosis or bleeding complications. Learning objective: Antithrombin deficiency is a rare disorder and data about coronary intervention for cases with antithrombin deficiency are limited. We successfully performed intervention with our anticoagulant management and it would be beneficial for future reference.

Malnutrition, hemodynamics and inflammation in heart failure with reduced, mildly reduced and preserved ejection fraction.

In patients with heart failure (HF) with reduced ejection fraction (HFrEF), malnutrition can be associated with intestinal congestion and systemic inflammation. These relationships have not been fully investigated in HF with mildly reduced EF (HFmrEF) and with preserved EF (HFpEF). We analyzed 420 patients with HF who underwent right heart catheterization. The relationships between hemodynamic parameters, C-reactive protein, and the controlling nutritional (CONUT) score were investigated in HFrEF, HFmrEF and HFpEF. The CONUT score of all patients was 2 [1, 4] (median [interquartile range]), and was not significantly different between the left ventricular EF (LVEF) categories (2 [1, 3] for HFrEF, 2 [1, 3] for HFmrEF, and 3 [1, 4] for HFpEF, p = 0.279). In multivariate linear regression analyses, there was a significant association between CRP and the CONUT score in HFmrEF and HFpEF, while brain natriuretic peptide and right atrial pressure were significantly associated with the CONUT score in HFrEF. Higher CONUT scores predicted a higher incidence of the composite endpoint of death or HF hospitalization within 12 months without an interaction with LVEF (p = 0.980). The CONUT score was an independent predictor of the composite endpoint, death, and HF hospitalization after adjustment for confounders in the multivariate analysis. In conclusion, inflammation was associated with malnutrition in HFmrEF and HFpEF, while congestion was an independent predictor of malnutrition in HFrEF. Malnutrition predicted worse outcomes regardless of LVEF.

Acute Myocarditis in a Patient Following mRNA-1273 SARS-CoV-2 Vaccination.

We herein report a case of acute myocarditis possibly related to the second dose of an mRNA-coronavirus disease 2019 vaccine in a 45-year-old woman with no remarkable medical history. She had a fever for one week following the second dose of the mRNA-1273 severe acute respiratory syndrome coronavirus 2 vaccine. One week later, she presented with chest pain and electrocardiogram changes. Her serum troponin levels were elevated upon admission. Echocardiography showed segmental wall motion abnormalities of the apex, apical portion of the anterior and inferior walls. The findings of cardiac magnetic resonance imaging were consistent with acute myocarditis.

Clinical Predictors of Coronary Artery Plaque Progression by Quantitative Serial Assessment Using 320-Row Computed Tomography Coronary Angiography in Asymptomatic Patients with Type 2 Diabetes Mellitus.

BACKGROUND: Natural history of coronary plaque progression (PP) in patients with diabetes mellitus (DM) remains unclear. This study aimed to investigate the clinical predictors of coronary PP in patients with DM. METHODS: In this prospective observational study, we analyzed 70 asymptomatic patients (age, 64.4 years; male, 67%) with type 2 DM without prior history of coronary artery disease who underwent serial 320-row computed tomography coronary angiography with an interscan interval of more than 24 months (median 37.7 months). Study endpoint was PP, which was defined if coronary plaque volumes (PVs) at follow-up minus PVs at baseline was >0. We evaluated plaque composition using the Hounsfield Unit thresholds and insulin resistance estimated by the homeostasis model assessment of insulin resistance (HOMA-IR). RESULTS: Thirty-nine patients who showed PP had a higher increase in hemoglobin A1c (⊿HbA1c) from baseline to follow-up than those without PP (0.3% ± 0.8% vs -0.4% ± 1.1%; p = 0.01), although there was no statistical difference in HbA1c at baseline (7.1 ± 0.5% vs. 7.3 ± 1.4%; p = 0.24). In multivariable analysis, ⊿HbA1c [odds ratio (OR): 3.05; 95% confidence interval (CI): 1.39-6.67; p = 0.001] was an independent predictor for PP. Increase in low-density lipoprotein cholesterol (⊿LDL-C), not ⊿HbA1c, was significantly correlated to percent change in necrotic core (NC) volume (ß-coefficients: 0.04; 95% CI: 0.004 - 0.08; p = 0.03). Among 48 patients without insulin therapy, patients with PP (n = 28) had a higher increase in HOMA-IR than those without PP (n = 20) (0.95 ± 2.00 vs. -0.63 ± 1.31; p = 0.003). CONCLUSIONS: Increase in HbA1c and HOMA-IR was associated with PP in asymptomatic patients with type 2 DM, whereas increase in LDL-C was correlated to increase in NC.