Absence of first-pass isolation is associated with poor pulmonary vein isolation durability and atrial fibrillation ablation outcomes.

BACKGROUND: Pulmonary vein (PV) reconnection is the main cause of atrial fibrillation (AF) recurrence. This study aimed to examine the effect of first-pass PV isolation (PVI) on PV reconnection frequency during the procedure and on AF ablation outcomes. METHODS: This retrospective study included 446 patients with drug-refractory AF (370 men, aged 64 ± 10 years) who underwent initial PVI using an open-irrigated contact force catheter between January 2015 and October 2016. We investigated the effect of first-pass PVI on PV reconnection during spontaneous PV reconnection and dormant conduction after an adenosine triphosphate challenge. RESULTS: First-pass PVI was achieved in 69% (617/892) of ipsilateral PVs, of which we observed PV reconnection during the procedure in 134 (22%) PVs. This value was significantly lower than that observed in those without first-pass PVI (50%, 138/275) (P < .0001). We divided the subjects into two groups based on the presence or absence of first-pass PVI in at least one of two ipsilateral PVs: first-pass (n = 383, 86%) and non-first-pass groups (n = 63, 14%). The 2-year AF recurrence-free rate was significantly higher in the first-pass group than in the other group (75% vs 59%, log-rank P = .032). In 78 patients with repeat AF ablation, the PV reconnection rate in the second procedure was significantly lower in PVs that had first-pass isolation in the first procedure (34% vs 73%, P < .0001). CONCLUSIONS: Absence of first-pass PVI was associated with a higher frequency of spontaneous PV reconnection and dormant conduction and poor ablation outcomes. First-pass isolation may be a useful marker for better PVI durability.

Comparison of the Safety and Efficacy of Automated Annotation-Guided Radiofrequency Ablation and 2nd-Generation Cryoballoon Ablation in Paroxysmal Atrial Fibrillation.

BACKGROUND: Automated ablation lesion annotation with optimal settings for parameters including contact force (CF) and catheter stability may be effective for achieving durable pulmonary vein isolation. Methods and Results: We retrospectively examined 131 consecutive patients who underwent initial catheter ablation (CA) for paroxysmal atrial fibrillation (PAF) by automatic annotation system (VISITAG module)-guided radiofrequency CA (RFCA) (n=61) and 2nd-generation cryoballoon ablation (CBA) (n=70) in terms of safety and long-term efficacy. The automatic annotation criteria for the RFCA group were as follows: catheter stability range of motion ≤1.5 mm, duration ≥5 s, and CF ≥5 g. We ablated for >20 s with a force-time integral >150 gs at each site, before moving to the next site. Each interlesion distance was <6 mm. Procedural complications were more frequent in the CBA group (1.6% vs. 10.0%, P=0.034). Across a median follow-up of 2.98 years, 88.5% and 70.0% of patients in the RFCA and CBA groups, respectively, were free from recurrence (log-rank test, P=0.0039). There was also a significant difference in favor of RFCA with respect to repeat ablations (3.3% vs. 24.3%, log-rank test, P=0.0003). CONCLUSIONS: RF ablation guided by an automated algorithm that includes CF and catheter stability parameters showed better long-term outcomes than CBA in the treatment of patients with PAF without increasing complications.

High Baseline Lipoprotein(a) Level as a Risk Factor for Coronary Artery Calcification Progression: Sub-analysis of a Prospective Multicenter Trial.

Lipoprotein(a), or Lp(a), is a low-density lipoprotein-like particle largely independent of known risk factors for, and predictive of, cardiovascular disease (CVD). We investigated the association between baseline Lp(a) levels and the progression of coronary artery calcification (CAC) in patients with hypercholesterolemia undergoing statin therapy. This study was a sub-analysis of a multicenter prospective study that evaluated the annual progression of CAC under intensive and standard pitavastatin treatment with or without eicosapentaenoic acid in patients with an Agatston score of 1 to 999, and hypercholesterolemia treated with statins. We classified the patients into 3 groups according to CAC progression. A total of 147 patients (mean age, 67 years; men, 54%) were analyzed. The proportion of patients with Lp(a) > 30 mg/dL significantly increased as CAC progressed (non-progression; 5.4%, 0100; 23.6%). Logistic regression analysis showed that Lp(a) > 30 mg/dL was an independent predictor of the annual change in Agatston score > 100 (OR: 5.51; 95% CI: 1.28-23.68; p=0.02), even after adjusting for age, sex, hypertension, diabetes mellitus, current smoking, body mass index, and lipid-lowering medications. Baseline Lp(a) >30 mg/dL was a predictor of CAC progression in this population of patients with hypercholesterolemia undergoing statin therapy.

3D-printed aortic stenosis model with fragile and crushable calcifications for off-the-job training and surgical simulation.

Surgical simulation devices can be helpful and cost-effective adjuncts to on-the-job training. In this tutorial we present our method for creating an aortic stenosis model with realistically fragile and crushable calcifications, using modern 3D-printing techniques.  The model can be used for training and surgical simulation and is an effective aid to learning for young cardiovascular surgeons.

To what extent can 3D model replicate dimensions of individual mitral valve prolapse?

Determining the complex geometry of mitral valve prolapse is often difficult. We constructed 3D models of six prolapsed mitral valves for surgical assessment, and evaluated how accurately the models could replicate individual valve dimensions. 3D polygon data were constructed based on an original segmentation method for computed tomography images. The model's replication performance was confirmed via dimensional comparison between the actual hearts during surgery and those models. The results revealed that the prolapsed segments matched in all cases; however, torn chordae were replicated in four cases. The mean height differences were 0.0 mm (SD 1.6, range - 2 to + 2 mm) for the anterolateral side, 0.0 mm (SD 1.7, range - 2 to + 2 mm) for the prolapsed leaflet center, and - 1.5 mm (SD 0.6, range - 1 to - 2 mm) for the posteromedial side. Regression analysis showed a strong and positive correlation, and Bland-Altman plots indicated quantitative similarity of the models to the actual hearts. We concluded that our 3D valve models could replicate the actual mitral valve prolapses within acceptable dimensional differences. Our concepts are useful for better 3D valve creation and better surgical planning with reliable 3D valve models.

Eicosapentaenoic acid prevents arterial calcification in klotho mutant mice.

BACKGROUND: The klotho gene was identified as an "aging-suppressor" gene that accelerates arterial calcification when disrupted. Serum and vascular klotho levels are reduced in patients with chronic kidney disease, and the reduced levels are associated with arterial calcification. Intake of eicosapentaenoic acid (EPA), an n-3 fatty acid, reduces the risk of fatal coronary artery disease. However, the effects of EPA on arterial calcification have not been fully elucidated. The aim of this study was to determine the effect of EPA on arterial calcification in klotho mutant mice. METHODS AND RESULTS: Four-week-old klotho mutant mice and wild-type (WT) mice were given a diet containing 5% EPA (EPA food, klotho and WT: n = 12, each) or not containing EPA (control food, klotho and WT: n = 12, each) for 4 weeks. Calcium volume scores of thoracic and abdominal aortas assessed by computed tomography were significantly elevated in klotho mice after 4 weeks of control food, but they were not elevated in klotho mice after EPA food or in WT mice. Serum levels of EPA and resolvin E1, an active metabolite of EPA, in EPA food-fed mice were significantly increased compared to those in control food-fed mice. An oxidative stress PCR array followed by quantitative PCR revealed that NADPH oxidase-4 (NOX4), an enzyme that generates superoxide, gene expression was up-regulated in arterial smooth muscle cells (SMCs) of klotho mice. Activity of NOX was also significantly higher in SMCs of klotho mice than in those of WT mice. EPA decreased expression levels of the NOX4 gene and NOX activity. GPR120, a receptor of n-3 fatty acids, gene knockdown by siRNA canceled effects of EPA on NOX4 gene expression and NOX activity in arterial SMCs of klotho mice. CONCLUSIONS: EPA prevents arterial calcification together with reduction of NOX gene expression and activity via GPR120 in klotho mutant mice.

Morphological analysis and preoperative simulation of a double-chambered right ventricle using 3-dimensional printing technology.

We present a case of a double-chambered right ventricle in adulthood, in which we tried a detailed morphological assessment and preoperative simulation using 3-dimensional (3D) heart models for improved surgical planning. Polygonal object data for the heart were constructed from computed tomography images of this patient, and transferred to a desktop 3D printer to print out models in actual size. Medical staff completed all of the work processes. Because the 3D heart models were examined by hand, observed from various viewpoints and measured by callipers with ease, we were able to create an image of the complete form of the heart. The anatomical structure of an anomalous bundle was clearly observed, and surgical approaches to the lesion were simulated accurately. During surgery, we used an incision on the pulmonary infundibulum and resected three muscular components of the stenosis. The similarity between the models and the actual heart was excellent. As a result, the operation for this rare defect was performed safely and successfully. We concluded that the custom-made model was useful for morphological analysis and preoperative simulation.

Diagnosis of anomalous origin of the right coronary artery using multislice computed tomography: evaluation of possible causes of myocardial ischemia.

Anomalous origin of the right coronary artery (RCA) is a rare condition, but may cause myocardial ischemia and sudden death. Multislice computed tomography, which allows three-dimensional visualization of the coronary artery with high spatial resolution, may be the most promising imaging modality for diagnosing this anomaly. We describe a patient with anomalous origin of the RCA arising from the left sinus of Valsalva. Volume rendering, and axial and curved multiplanar images showed stenosis in the proximal portion of the RCA that coursed between the aorta and the pulmonary artery, and an acute angled take-off of the RCA from the aorta. Three-dimensional virtual angioscopic images showed a hypoplastic RCA orifice and luminal narrowing in the proximal portion of the RCA. Multislice computed tomography was thought to be useful for detecting anomalous origin of the RCA and for evaluating possible causes of myocardial ischemia.

Myocardial perfusion imaging using adenosine triphosphate stress multi-slice spiral computed tomography: alternative to stress myocardial perfusion scintigraphy.

BACKGROUND: The present study was designed to: (i) detect myocardial ischemia in contrast enhanced multi-slice spiral computed tomography (CE-MSCT) using adenosine triphosphate (ATP) pharmacological stress test; and (ii) evaluate the potential of ATP stress CE-MSCT in a clinical setting. METHODS AND RESULTS: Twelve patients underwent ATP stress CE-MSCT and stress thallium-201 myocardial perfusion scintigraphy (MPS) and 9 of the patients received conventional coronary angiography (CAG). Dual CE-MSCT scans were performed for stress and rest images, with and without intravenous infusion of ATP (0.16 mg.kg-1.min-1) at intervals of 20 min. Myocardial perfusion and coronary artery were visually evaluated using MSCT and compared the results obtained from MPS and CAG. Of 36 territories, stress images of CE-MSCT described 26 hypo-perfusion areas and MPS described 22 redistributions. The agreement between MSCT and MPS was 83% (30/36, p<0.05). In 141 coronary artery segments of 9 patients undergoing CAG, rest images of CE-MSCT, which had significantly higher assessability than stress images (89% vs 48%, p<0.05), described 76% (13/17) of culprit coronary stenoses. CONCLUSIONS: Although CT-angiography should be currently assessed using rest images, ATP stress CE-MSCT can describe both ATP-induced myocardial ischemia and coronary artery stenoses in patients with coronary artery disease.

Detection of anomalous origins of the coronary artery by means of multislice computed tomography.

BACKGROUND: Anomalous origins of the coronary artery are rare, but may cause myocardial ischemia and sudden death. Thus, their reliable identification is crucial for any imaging method that attempts coronary artery visualization and of those available multislice computed tomography (MSCT), which provides excellent spatial resolution, may be the most promising. METHODS AND RESULTS: In consecutive 1,153 patients, MSCT identified 5 patients (0.43 %) with an anomalous origin of the coronary artery. The left circumflex artery (LCX) originated from the right sinus of Valsalva in 1 patient, and the right coronary artery originated from the left sinus of Valsalva and coursed between the aortic root and the pulmonary artery in 3 patients. In 1 patient, MSCT identified the absence of the LCX and high-grade atherosclerotic stenosis in the right coronary artery. CONCLUSION: MSCT can detect the anomalous origin and course of the coronary artery in relation to the great vessels. It is also useful for identifying atherosclerotic coronary artery disease superimposed on the anomalous vascular system.

Carotenoid-induced cooperative formation of bacterial photosynthetic LH1 complex.

A simple reconstitution technique has been developed and then applied to prepare a series of light-harvesting antenna 1 (LH1) complexes with a programmed carotenoid composition, not available from native photosynthetic membranes. The complexes were reconstituted with different C(40) carotenoids, having two structural parameters variable: the functional side groups and the number of conjugated C-C double bonds, systematically increasing from 9 to 13. The complexes, differing only in the type of carotenoid, bound to an otherwise identical bacteriochlorophyll-polypeptide matrix, can serve as a unique model system in which the relationship between the carotenoid character and the functioning of pigment-protein complexes can be investigated. The reconstituted LH1 complexes resemble the native antenna, isolated from wild-type Rhodospirillum rubrum, but their coloration is entirely determined by carotenoid. Along with the increase in its conjugation size, the carotenoid absorption transitions gradually shift to the red. Thus, the extension of the conjugation size of the antenna carotenoids provides a mechanism for the spectral tuning of light harvesting in the visible part of the spectrum. The carotenoids in the reconstitution system promote the LH1 formation and seem to bind and transfer the excitation energy specifically only to a species with characteristically red-shifted absorption and emission maxima, apparently, due to a cooperative effect. Monitoring the LH1 formation by steady-state absorption and fluorescence spectroscopies reveals that in the presence of carotenoids it proceeds without spectrally resolved intermediates, leading directly to B880. The effect of the carotenoid is enhanced when the pigment contains the hydroxy or methoxy side groups, implying that, in parallel to hydrophobic interactions and pi-pi stacking, other interactions are also involved in the formation and stabilization of LH1.