Age-Related Differences in the Effects of Initial Aortic Valve Replacement vs. Conservative Strategy on Long-Term Outcomes in Asymptomatic Patients With Severe Aortic Stenosis.

BACKGROUND: This study aimed to evaluate the effect of the initial aortic valve replacement (AVR) strategy relative to a conservative strategy on long-term outcomes stratified by age among asymptomatic patients with severe aortic stenosis (AS).Methods and Results:Among 1,808 asymptomatic severe AS patients in the CURRENT AS registry, there were 1,166 patients aged ≥75 years (initial AVR: n=124, and conservative: n=1,042), and 642 patients with age <75 years (initial AVR: n=167, and conservative: n=475). Median follow-up interval was 1,280 (interquartile range [IQR]: 1,012-1,611) days, and 1461 (IQR: 1,132-1,886) days in patients aged ≥ and <75 years, respectively. The favorable effect of the initial AVR strategy relative to conservative strategy for heart failure (HF) hospitalization was seen regardless of the age stratum (≥75 years: adjusted hazard ratio [HR] 0.13, 95% confidence interval [CI] 0.05-0.34, and <75 years: HR 0.37, 95% CI 0.14-0.99, interaction P=0.35). However, the lower mortality risk of the initial AVR strategy relative to conservative strategy was significant in patients aged ≥75 years, but not in patients <75 years, with significant interaction (HR 0.35, 95% CI 0.20-0.61, and HR 0.69, 95% CI 0.41-1.16, interaction P=0.016). CONCLUSIONS: The benefit of initial AVR in reducing HF hospitalization in asymptomatic patients with severe AS was consistently seen regardless of age. The magnitude of mortality benefit of initial AVR was greater in super-elder patients than in non-super-elder patients.

Limitations of lesion quality estimated by ablation index: An in vitro study.

LIMITATIONS OF THE ABLATION INDEX BACKGROUND: Ablation index (AI) is a novel marker of lesion quality from radiofrequency (RF) catheter ablation. However, AI reliability has not been fully validated by experimental data. The aim of the present study is to validate AI reliability for estimating lesion size using different settings for RF parameters: contact angle, power delivery, and contact force (CF). METHODS AND RESULTS: We evaluated the lesion size in porcine hearts (N = 108) after RF application at three different contact angles to the myocardium: perpendicular (90°), oblique (45°), and parallel (0°). At each angle, RF power at 25, 30, and 35 W was applied at target CF values of 5, 15, and 30 g as measured by the CF sensor to reach target AIs of 300, 400, 500, and 600. AI value was significantly correlated with lesion depth, width, and volume (R = 0.84, 0.82, and 0.87, respectively, all P < 0.001). Lesion depth decreased with smaller contact angles (45° and 0°). Furthermore, high-power RF energy (35 W) resulted in a significantly smaller lesion volume compared with standard-power energy (30 W). There were no significant differences in lesion size among CF settings. CONCLUSIONS: AI was strongly correlated with lesion depth, width, and volume, but only within a small range of contact angles and RF power delivery settings.

Optimal cutoff value of bipolar low-voltage in electroanatomic voltage mapping during atrial fibrillation rhythm.

BACKGROUND: Electroanatomic voltage mapping (EAVM) of the left atrium (LA) with multielectrodes is usually acquired during sinus rhythm (SR), and the feasibility of EAVM during atrial fibrillation (AF) rhythm is unclear. METHODS: We performed EAVM of LA during both SR and AF rhythm in 44 patients undergoing catheter ablation for AF and validated the optimal cutoff value of low-voltage area (LVA) during AF rhythm for detecting LVA defined as bipolar voltages ≤0.5 mV during SR. RESULTS: In each session, mean 829 and 552 points were acquired by multielectrodes during SR and AF rhythm, respectively. Mean proportion of LVA was 4.9% among LA surface area of 276.2 cm2 . Differences of LVA proportions between SR and AF rhythm were 5.8% (P < 0.001), 4.2% (P < 0.001), 2.7% (P < 0.001), 1.2% (P = 0.01), and -0.5% (P = 0.17) at the cutoff value of 0.4, 0.35, 0.3, 0.25, and 0.2 mV during AF rhythm, respectively. There was a good correlation between LVA proportions during SR and AF rhythm with cutoff value of 0.2 mV (R = 0.88, P < 0.001) and 37 patients (84.1%) had the discrepancy of LVA proportions within 3%. Furthermore, there was no significant difference between LVA proportions at each segment of LA. The discrepancy was relatively large in patients with large LA dimension and LVA during SR. CONCLUSION: EAVM during AF rhythm was feasible and the optimal cutoff value of LVA was 0.2 mV for detecting LVA ≤ 0.5 mV during SR. However, the evidence is restricted to patients with relatively small LVA.

[Severe Perioperative Coronary Artery Spasm in Thoracic Aortic Surgery; Report of Two Cases].

We report 2 cases of severe perioperative coronary artery spasm in thoracic aortic surgery. Case 1 was a 72-year-old male with a distal arch aneurysm of 74 mm while case 2 was a 74-year-old male with acute type A aortic dissection. We performed thoracic aortic repair (total arch replacement and ascending aorta replacement) under moderately hypothermic circulatory arrest (25 °C) and selective cerebral perfusion in both cases. ST elevation, abnormal left ventricular wall motion, and hypotension were noted intraoperatively. Because we were not able to wean the patients from the cardiopulmonary bypass, intraaortic balloon pump was initiated in case 1 and a coronary artery bypass graft was added in case 2. In addition to using vasodilators such as diltiazem, case 1 recovered without further intervention, but case 2 developed cardiopulmonary arrest and needed resuscitation on postoperative day 5 because of recurrence of coronary spasm. Perioperative coronary artery spasm is rare especially in aortic surgery, and may become lethal. Early recognition and special hemodynamic support is required.

Different Kinetics of Activated Clotting Time Among Uninterrupted Oral Anticoagulants During Catheter Ablation Procedure.

Activated clotting time (ACT) kinetics under uninterrupted oral anticoagulants (OACs) has not been fully evaluated. The present study is sought to validate ACT kinetics including stability under uninterrupted use of OACs during an ablation procedure in daily clinical practice. We prospectively enrolled consecutive 554 patients with atrial fibrillation who underwent catheter ablation procedure under uninterrupted OACs. We evaluated ACT kinetics at an interval of 15 minutes during the procedure and periprocedural complications among 5 OACs (dabigatran [N = 46], rivaroxaban [N = 125], apixaban [N = 129], edoxaban [N = 184], and warfarin [N = 70]). Compared with the dabigatran group, time to achieve target ACT was significantly longer in the rivaroxaban and apixaban groups, but not in the edoxaban and warfarin groups (8.7 vs 11.7 minutes, P < .001; 13.3 minutes, P < .001; 8.8 minutes, P = .64; 10.3 minutes, P = .19, respectively). Heparin dose to achieve target ACT was comparable except for the warfarin group, whereas, compared with the dabigatran group, time in therapeutic range of ACT within the first hour was comparable in the rivaroxaban and apixaban group but significantly lower in the edoxaban and warfarin groups (73.7 % vs 63.0%, P = .06; 67.0 %, P = .16; 59.2 %, P = .001; 58.2%, P = .004, respectively). In multiple regression analysis, low body weight, rivaroxaban, apixaban, and morning session had significant associations with time and heparin dose to achieve target ACT, and there were positive associations of dabigatran and apixaban with time in therapeutic range of ACT within the first hour. The incidence of periprocedural complications did not significantly differ among the 5 groups. Under uninterrupted OAC use in daily clinical practice, dabigatran showed faster achievement of target ACT and higher stability of ACT than other OACs.

The impact of current strategy using intracardiac echocardiography, lesion index, and minimum substrate ablation on clinical outcomes after catheter ablation procedure for atrial fibrillation.

PURPOSE: We developed the intracardiac echocardiography (ICE) technique to minimize radiation exposure and other recent technology during ablation procedure for atrial fibrillation (AF). The aim of this study was to validate the impact of the current strategy using the recent technology for AF ablation on outcomes after procedure. METHODS: We evaluated the safety and efficacy of the current strategy in consecutive set of patients undergoing first-time ablation for AF (N = 233) compared with the conventional strategy in earlier consecutive set of patients (N = 223). The current strategy included the technique of ICE to reduce radiation exposure, Ablation Index®-guided pulmonary veins isolation, and minimum substrate ablation targeting only for induced AF. Outcome measures were radiation exposure, procedure time, in-hospital adverse outcomes, and event-free survival from tachyarrhythmias. RESULTS: Puncture-to-ablation time was slightly, but significantly increased in the current strategy than in the conventional strategy (48.0 minutes vs 44.7 minutes, P = .002), although total procedure time was significantly decreased in the current strategy (143.9 minutes vs 156.9 minutes, P < .001). Likewise, radiation time and absorbed dose were significantly decreased in the current strategy (9.8 minutes vs 38.8 minutes, P < .001; 102.3 mGy vs 490.5 mGy, P < .001). The incidence of overall in-hospital adverse outcomes was 3.9% in the current strategy and each complication rate was comparable with the conventional protocol. The event-free survival from recurrent atrial tachyarrhythmias was not significantly different between two groups (72.3% vs 77.1% at 2-year, P = .32). CONCLUSION: The current strategy using the recent technology with ICE, lesion index, and minimum substrate ablation was feasible and reduced total procedure time and radiation exposure. However, the arrhythmia-free survival could not be improved.

Influence of low body weight on long-term clinical outcomes in patients with venous thromboembolism: From the COMMAND VTE registry.

INTRODUCTION: There is a paucity of data on the influence of low body weight on clinical outcomes in patients with acute venous thromboembolism (VTE). MATERIALS AND METHODS: The COMMAND VTE registry is a multicenter cohort study enrolling 3027 consecutive patients with acute symptomatic VTE. The current study population consisted of 2778 patients with available body weight value, who were divided into 2 groups; 1705 patients with lower body weight (≤60 kg) and 1073 patients with higher body weight (>60 kg). RESULTS: Patients with lower body weight were older (70.8 versus 60.9 years, P < 0.001), and more often women (75% versus 38%, P < 0.001), and more often had active cancer (27% versus 19%, P < 0.001) than those with higher body weight. The cumulative 5-year incidence of recurrent VTE was not significantly different between the 2 groups (10.6% versus 10.7%, P = 0.51). The cumulative 5-year incidences of major bleeding and all-cause death were significantly higher in patients with lower body weight than in those with higher body weight (14.6% versus 9.6%, P < 0.001, and 35.8% versus 19.8%, P < 0.001, respectively). The excess adjusted risk of patients with lower body weight relative to those with higher body weight remained significant for major bleeding and all-cause death (HR 1.57, 95%CI: 1.16-2.12, P = 0.003, and HR 1.50, 95%CI: 1.24-1.81, P < 0.001, respectively). CONCLUSIONS: In the current Japanese real-world registry, there were a high proportion of patients with low body weight, who had a higher risk for major bleeding and mortality without significant excess risk for recurrent VTE.