From the Circulation Family of Journals.

Abstract

HomeCirculationVol. 139, No. 9From the Circulation Family of Journals Free AccessIn BriefPDF/EPUBAboutView PDFView EPUBSections ToolsAdd to favoritesDownload citationsTrack citationsPermissions ShareShare onFacebookTwitterLinked InMendeleyReddit Jump toFree AccessIn BriefPDF/EPUBFrom the Circulation Family of Journals Originally published25 Feb 2019https://doi.org/10.1161/CIRCULATIONAHA.119.039891Circulation. 2019;139:1219–1224Circulation: Arrhythmia and ElectrophysiologyDespite the overall effectiveness of the second-generation cryoballoon (CB2) ablation for atrial fibrillation, the ideal number of freezing cycles is unclear. The AD-Balloon Study (Multicenter Study of the Validity of Additional Freeze Cycles for Cryoballoon Ablation) investigated the optimal strategy of freeze cycles and no benefit was found in the patients receiving additional 3-minute freeze cycles after pulmonary vein isolation with the CB2 ablation.Multicenter Study of the Validity of Additional Freeze Cycles for Cryoballoon Ablation in Patients With Paroxysmal Atrial FibrillationThe AD-Balloon StudyKoji Miyamoto, MD, PhDAtsushi Doi, MD, PhDKanae Hasegawa, MD, PhDYoshiaki Morita, MD, PhDTsuyoshi Mishima, MDIppei Suzuki, MSKenichi Kaseno, MD, PhDKenzaburo Nakajima, MDNaoya Kataoka, MD, PhDTsukasa Kamakura, MD, PhDMitsuru Wada, MDKenichiro Yamagata, MD, PhDKohei Ishibashi, MD, PhDYuko Y. Inoue, MD, PhDSatoshi Nagase, MD, PhDTakashi Noda, MD, PhDTakeshi Aiba, MD, PhDMasanori Asakura, MD, PhDChisato Izumi, MD, PhDTeruo Noguchi, MD, PhDHiroshi Tada, MD, PhDMasahiko Takagi, MD, PhDSatoshi Yasuda, MD, PhDKengo F. Kusano, MD, PhDCorrespondence to: Kengo F. Kusano, MD, PhD, Department of Cardiovascular Medicine, National Cerebral and Cardiovascular Center, 5-7-1 Fujishiro-dai, Suita, Osaka 565-8565, Japan. Email [email protected]comBACKGROUND: Pulmonary vein isolation (PVI) is a cornerstone of catheter ablation in patients with paroxysmal atrial fibrillation, and balloon-based ablation has been recently performed worldwide. The second-generation cryoballoon (CB2) ablation has proven to be highly effective in achieving freedom from paroxysmal atrial fibrillation. However, there are some debatable questions, including the ideal number of freeze cycles.METHODS: The AD-Balloon study (Multicenter Study of the Validity of Additional Freeze Cycles for Cryoballoon Ablation) was designed as a prospective, multicenter, and randomized clinical trial for investigation of the optimal strategy of freeze cycles for the CB2 ablation. One hundred and ten consecutive patients (aged 64±11 years) were randomly assigned to 2 groups after achieving a PVI by the CB2 ablation: 3-minute freeze cycles were added to each pulmonary vein (AD group: n=55) or not (non-AD group: n=55). Delayed-enhancement MRI was also performed 1 to 2 months after the PVI to assess the ablation lesions.RESULTS: The patient characteristics did not differ between the 2 groups. A complete PVI was achieved in all patients. The total number of freeze cycles and durations for all pulmonary veins were significantly shorter in the non-AD group than in the AD group (5.7±1.6 versus 9.1±1.6 cycles, P<0.0001, and 932±244 versus 1483±252 seconds, P<0.0001). The cumulative freedom from any atrial tachyarrhythmia at 1 year was 87.3% in the AD group and 89.1% in the non-AD group (log-rank test P=0.78). There was no significant difference in the frequency of gaps on the PVI lines in the delayed-enhancement MRI (46% in the AD group versus 36% in the non-AD group; P=0.38).CONCLUSIONS: No benefit was found in the patients receiving additional 3-minute freeze cycles after the complete PVI with the CB2 ablation, suggesting that an insurance freeze after achieving a PVI with the CB2 may be unnecessary and time consuming.Circ Arrhythm Electrophysiol. 2019;12:e006989. doi: 10.1161/CIRCEP.118.006989.Circulation: Genomic and Precision MedicineThe long-term safety of PCSK9 (proprotein convertase subtilisin/kexin type 9) inhibitors is unclear. Using patients from the UK Biobank, this study analyzed the association of a low-density lipoprotein–lowering variant in the PCSK9 gene and 2 low-density lipoprotein–lowering HGCMR variants with 80 diseases and traits. The study found an association between type 2 diabetes mellitus and both the PCSK9 gene and the HGCMR variants, suggesting that long-term use of PCSK9 inhibitors, like statins, may be associated with increased risk of type 2 diabetes mellitus. Future studies are warranted to investigate further potential side effects.Genetic Assessment of Potential Long-Term On-Target Side Effects of PCSK9 (Proprotein Convertase Subtilisin/Kexin Type 9) InhibitorsChristopher P. Nelson, PhDFlorence Y. Lai, MPhilMintu Nath, PhDShu Ye, PhDThomas R. Webb, PhDHeribert Schunkert, MDNilesh J. Samani, FRCPCorrespondence to: Nilesh J. Samani, FRCP, Department of Cardiovascular Sciences, BHF Cardiovascular Research Centre, University of Leicester, Glenfield Hospital, Groby Rd, Leicester LE3 9QP, United Kingdom. Email [email protected]ac.ukBACKGROUND: Although short-term trials have suggested that PCSK9 (proprotein convertase subtilisin/kexin type 9) inhibitors are safe and reduce risk of cardiovascular diseases, their long-term safety is unclear. Genetic variants associated with lower activity of a gene can act as proxies to identify potential long-term side effects of drugs as recently exemplified by association of LDL (low-density lipoprotein)-lowering variants in the HMGCR (target for statins) and PCSK9 genes with increased risk of type 2 diabetes mellitus (T2DM). However, analyses of the full spectrum of potential side effects of PCSK9 inhibition using a genetic approach have not been undertaken.METHODS: We examined the association of an LDL-lowering variant in the PCSK9 gene (T allele of rs1159147), as well as 2 LDL-lowering HGCMR variants (G allele of rs17238484 and T allele of rs12916) with 80 diseases and traits in up to 479 522 individuals in UK Biobank.RESULTS: The PCSK9 T allele was significantly (Bonferroni P<6.25×10−4) associated with risk of T2DM, increased body mass index, waist circumference, waist-hip ratio, diastolic blood pressure, type 1 diabetes mellitus, and insulin use. The HMGCR variants were also associated with risk of T2DM, although their previously reported associations with anthropometric traits were found to be confounded. Mediation analysis suggested that the association of the PCSK9 T allele with risk of T2DM but not diastolic blood pressure was largely independent of its association with body mass index and central obesity. Nominally significant associations of the PCSK9 T allele were also seen with peptic ulcer disease, depression, asthma, chronic kidney disease, and venous thromboembolism.CONCLUSIONS: Our findings support previous genetic analyses suggesting that long-term use of PCSK9 inhibitors, like statins, may be associated with increased risk of T2DM. Some other potential side effects need to be looked for in future studies of PCSK9 inhibitors, although we did not find signals that raise substantial concerns about their long-term safety.Circ Genom Precis Med. 2019;12:e002196. doi: 10.1161/CIRCGEN.118.002196.Circulation: Cardiovascular ImagingThis study evaluates the impact of the mitral annular calcium (MAC) score on the development of conduction system abnormalities (CSA) after transcatheter aortic valve implantation. The MAC score was an independent predictor of CSA in these patients, and studies to further validate a MAC score assessment as part of the pretranscatheter aortic valve implantation evaluation are suggested.Mitral Annulus Calcium ScoreAn Independent Predictor of New Conduction System Abnormalities in Patients After Transcatheter Aortic Valve ImplantationYafim Brodov, MD, PhDEli Konen, MDMattia Di Segni, MDDavid Samoocha, MDFernando Chernomordik, MDIsrael Barbash, MDEhud Regev, MDEhud Raanani, MDVictor Guetta, MDAmit Segev, MDPaul Fefer, MDMichael Glikson, MDOrly Goitein, MDCorrespondence to: Yafim Brodov, MD, PhD, Heart Institute, Sheba Medical Center, Tel Hashomer, Tel-Aviv University, Tel Hashomer 52621, Israel. Email yafim.[email protected]comBACKGROUND: The risk of conduction system abnormalities (CSA) after transcatheter aortic valve implantation remains high. We aimed to evaluate the impact of mitral annular calcium (MAC) score on the development of CSA after transcatheter aortic valve implantation.METHODS: Consecutive patients (n=168), with severe AoV stenosis, without prior CSA, underwent computed tomography transcatheter AoV implantation followed by device implantation; CoreValve (n=72) and SAPIEN (n=96). MAC, AoV, and left ventricular outflow tract calcium (Ca++) scores were quantitated from noncontrast ECG-gated computed tomography using Agatston method. The primary end point was a combination of complete left bundle-branch block or high-degree atrioventricular block. Logistic regression was used to analyze the predictive value of Ca++ scores of different locations.RESULTS: The primary end point was documented in 62% of the fourth quartile MAC score (>2700) patients as compared with 31% of the first quartile (<140); P=0.03. Logistic regression analysis documented MAC score as an independent predictor either of primary end point as a continuous variable (odds ratio: 1.02, 95% [CI]: 1.00–1.03, P=0.021) or as quartile cutoffs, whereas Q4 was a strong and independent predictor (odds ratio: 3.69, 95% [CI]: 1.37–9.95, P=0.010).CONCLUSIONS: MAC score was found to be an independent predictor of CSA in patients undergoing transcatheter aortic valve implantation without preexisting CSA. Therefore, the current study suggests that patients with high MAC score category (fourth MAC score quartile) should be considered at high risk for CSA, warranting closer monitoring.CLINICAL TRIAL REGISTRATION: URL: https://www.clinicaltrials.gov. Unique identifier: NCT02023060.Circ Cardiovasc Imaging. 2019;12:e007508. doi: 10.1161/CIRCIMAGING.117.007508.Circulation: Cardiovascular InterventionsObesity has become more prevalent among patients undergoing cardiac catheterization, and higher patient body mass index (BMI) results in higher patient radiation doses during coronary angiography. This study shows significantly higher physician radiation dose with higher patient BMI. Additional studies are warranted to investigate the potential adverse effects on physicians resulting from the increased radiation doses during coronary angiography.Patient Body Mass Index and Physician Radiation Dose During Coronary AngiographyIs the Obesity Epidemic Impacting the Occupational Risk of Physicians in the Catheterization Laboratory?Ryan D. Madder, MDStacie VanOosterhout, MedAbbey Mulder, BSN, RNTaylor Ten Brock, BSAustin T. Clarey, MDJessica L. Parker, MSMark E. Jacoby, MDCorrespondence to: Ryan D. Madder, MD, Frederik Meijer Heart and Vascular Institute, Spectrum Health, 100 Michigan St NE, Grand Rapids, MI 49503. Email ryan.[email protected]orgBACKGROUND: Consistent with the increasing prevalence of obesity in the general population, obesity has become more prevalent among patients undergoing cardiac catheterization. This study evaluated the association between patient body mass index (BMI) and physician radiation dose during coronary angiography.METHODS AND RESULTS: Real-time radiation exposure data were collected during consecutive coronary angiography procedures. Patient radiation dose was estimated using dose area product. Physician radiation dose in each case was recorded by a dosimeter worn by the physician and is reported as the personal dose equivalent (Hp10). Patient BMI was categorized as <25.0, 25.0 to 29.9, 30.0 to 34.9, 35.0 to 39.9, and ≥40. Among 1119 coronary angiography procedures, significant increases in dose area product and physician radiation dose were observed across increasing patient BMI categories (P<0.001). Compared with a BMI <25, a patient BMI ≥40 was associated with a 2.1-fold increase in patient radiation dose (dose area product, 91.8 [59.6–149.2] versus 44.5 [25.7–70.3] Gy×cm2; P<0.001) and a 7.0-fold increase in physician radiation dose (1.4 [0.2–7.1] versus 0.2 [0.0–2.9] μSv; P<0.001). By multiple regression analysis, patient BMI remained independently associated with physician radiation dose (dose increase, 5.2% per unit increase in BMI; 95% CI, 3.0%–7.5%; P<0.0001).CONCLUSIONS: Among coronary angiography procedures, increasing patient BMI was associated with a significant increase in physician radiation dose. Additional studies are needed to determine whether patient obesity might have adverse effects on physicians, in the form of increased radiation doses during coronary angiography.Circ Cardiovasc Interv. 2019;12:e006823. doi: 10.1161/CIRCINTERVENTIONS.118.006823.Circulation: Cardiovascular Quality and OutcomesThis Policy Brief discusses the complex and ongoing debate around volume requirements for the performance of transcatheter aortic valve replacement (TAVR). There has been significant growth in the number of TAVR centers after the Centers for Medicare & Medicaid Services (CMS) consensus statement, and the authors suggest a need for the CMS to reevaluate the initial volume threshold requirements.Volume Considerations for Transcatheter Aortic Valve Replacement in Medicare’s National Coverage DeterminationDevraj Sukul, MD, MScJoseph Allen, MADharam J. Kumbhani, MD, SMCorrespondence to: Dharam J. Kumbhani, MD, SM, Department of Internal Medicine, Division of Cardiology, UT Southwestern Medical Center, 5323 Harry Hines Blvd, Dallas, TX 75390-9047. Email [email protected]harvard.eduPolicy ContextOn the heels of the pivotal Placement of Aortic Transcatheter Valves randomized controlled trial,1 the US Food and Drug Administration approved transcatheter aortic valve replacement (TAVR) for commercial use in November 2011. Shortly after this in May 2012, the Centers for Medicare and Medicaid Services (CMS) issued a National Coverage Determination (NCD),2 marking the beginning of commercial TAVR in the United States. To ensure the rational dispersion of a major new therapy and high-quality TAVR care throughout the country, the NCD stipulated specific hospital and operator requirements necessary to start or maintain a TAVR program—including procedural volume thresholds.2 For the most part, these thresholds were based on the recommendations outlined in a multisociety expert consensus statement on operator and institutional requirements for TAVR published in 2012 (Table).3