Atrial fibrillatory wave amplitude revisited: A predictor of recurrence after catheter ablation independent of the degree of left atrial structural remodeling.

BACKGROUND: The fibrillatory wave amplitude (FWA) during atrial fibrillation (AF) is thought to reflect structural atrial remodeling, but it remains unclear what determines the FWA. METHODS: 114 consecutive patients were prospectively studied who underwent catheter ablation of AF. The mean FWA was computed by automated surface ECG analyses. The extent of the left atrial (LA) voltage-defined atrial fibrosis and conduction properties were estimated by a three-dimensional high-density electroanatomical mapping system. The LA size was evaluated by transthoracic echocardiography. The study patients were divided into 2 groups according to an FWA in lead V1 above the median value of 46 µV (high FWA group, n=57) or below 46 µV (low FWA group, n=57). RESULTS: There were no differences in the age, gender, CHADS2 score, prevalence of paroxysmal AF, medications, ablation strategy, and LA volume index between the two groups. The LA low voltage areas in the low FWA group were not different from those in the high FWA group. The total LA activation time and local LA conduction velocity did not differ between the two groups. During a median follow-up of 710 days, the recurrence rate after ablation was significantly higher in patients with a low FWA than a high FWA (log-rank P=0.02). In a multivariate analysis, non-paroxysmal AF, the LA volume index, and FWA were independent predictors of recurrence after　ablation. CONCLUSIONS: The FWA was not correlated with the markers of atrial structural remodeling. Nevertheless, the FWA could still provide information for predicting the clinical outcome after AF ablation.

Last Entrainment Sequence: A Novel Diagnostic Technique for Atrial Tachycardia Mimicking Other Supraventricular Tachycardias.

BACKGROUND: Adenosine-sensitive re-entrant atrial tachycardia (AT) originating from near the atrioventricular (AV) node or AV annulus resembles other supraventricular tachycardias (SVTs), and the differential diagnosis is sometimes challenging. OBJECTIVES: This study sought to develop a novel technique to distinguish adenosine-sensitive re-entrant AT from AV nodal re-entrant tachycardia (AVNRT) and orthodromic reciprocating tachycardia (ORT). METHODS: The study retrospectively studied 117 re-entrant SVTs that were successfully entrained by atrial overdrive pacing (AOP) (27 adenosine-sensitive re-entrant ATs, 63 AVNRTs, 27 ORTs). If the second atrial electrogram after AOP (A2) at the earliest atrial activation site (EAAS) accelerated to the pacing cycle length, the EAAS was considered orthodromically activated. Then, we compared the sequence of A2 and the last entrained His bundle (H∗) and QRS complex (V∗). The study hypothesized that the last entrained impulse would activate the EAAS before it enters the AV node, His bundle, and ventricle during AT (A2-H∗-V∗) but would activate the EAAS after the His bundle activation during AVNRT and ORT (H∗-V∗-A2 or H∗-A2-V∗). RESULTS: Orthodromic EAAS activation was documented during AOP in 84 SVTs (72%) when performing AOP from sites proximal to the entrance of SVTs. A2-H∗-V∗ responses were observed in 21 of 25 ATs, but were never for AVNRTs or ORTs. All ORTs and fast-slow AVNRTs had H∗-V∗-A2 responses. Eleven of 21 slow-fast AVNRTs had H∗-A2-V∗ responses. The sensitivity, specificity, and positive and negative predictive values of the A2-H∗-V∗ response for diagnosing AT were 84%, 100%, 100%, and 94%, respectively. CONCLUSIONS: The last entrainment sequence was useful for differentiating ATs with diagnostic difficulties.

Differences in pharmacological property between combined therapy of the vasopressin V2-receptor antagonist tolvaptan plus furosemide and monotherapy of furosemide in patients with hospitalized heart failure.

BACKGROUND: Tolvaptan has been shown to improve congestion in heart failure patients. The purpose of this study was to evaluate the pharmacology and clinical efficacy of combined tolvaptan and furosemide therapy. METHODS: This study included 40 patients with systemic volume overload who were hospitalized for heart failure. Patients who showed no improvement in the condition after receiving 20 mg intravenous furosemide were included and were randomly selected to receive tolvaptan as an add-on to furosemide or to receive an increased dose of furosemide. We evaluated the bioelectrical impedance analyzer parameters, the parameters of the inferior vena cava using echocardiography, vital signs, body weight, urine output, and laboratory data for 5 days. RESULTS: In the changes from baseline between intracellular water volume (ICW) and extracellular water volume (ECW) after additional use of tolvaptan or furosemide from Day 1 to Day 5, there were no significant differences observed between ICW and ECW over 5 days in the tolvaptan + furosemide group, although differences were found in the furosemide group from Day 2 onward. Changes in the respiratory collapse of inferior vena cava increased significantly, and systolic blood pressure decreased significantly only in the furosemide group. CONCLUSIONS: The present study clearly demonstrates that combined therapy with tolvaptan and furosemide removed excess ICW and ECW to an equal extent, while furosemide alone primarily removed ECW, including intravascular water.

Clinical significance of arterial stiffness as a factor for hospitalization of heart failure with preserved left ventricular ejection fraction: a retrospective matched case-control study.

BACKGROUND: Previous studies have been conducted to identify characteristics of patients with heart failure with preserved ejection fraction (HFpEF), but the risk factors of HFpEF remain unclear. We investigated the associations between arterial stiffness and the risk of hospitalization for HFpEF patients. METHODS: For the case group, we enrolled patients with preserved EF who had been hospitalized for HF from April 2013 to March 2015 and examined the cardio-ankle vascular index (CAVI). For the control group, we enrolled outpatients with preserved EF and with hypertension, diabetes mellitus, dyslipidemia, and/or coronary artery disease but who did not present with HF symptoms and had never been diagnosed or treated for HF during the same period. The control group matched with the case group for age and sex. The association between hospitalized HFpEF and clinical variables was analyzed using conditional logistic regression models. RESULTS: The CAVI value was significantly higher in patients with hospitalized HFpEF compared with patients with the control [10.4 (9.8-11.0) vs. 9.2 (8.1-10.0), p < 0.001). On the multivariate conditional logistic regression analysis, high CAVI (OR 6.76, 95% CI 2.28-20.10, p < 0.001) and anemia (OR 3.91, 95% CI 1.47-10.40, p = 0.006) were independently associated with hospitalization of HFpEF patients. CONCLUSIONS: The present study has demonstrated that the high value of CAVI was independently associated with the hospitalization of HFpEF patients.