In this task, you are given a passage which has a question and the context. You have to generate an answer to the question based on the information present in the context.

[Q]: Context: We sought to determine whether outcomes of chronic total occlusion (CTO) percutaneous coronary intervention (PCI) vary according to CTO target vessel: left anterior descending artery (LAD), left circumflex artery (LCX), and right coronary artery (RCA).', 'We evaluated the clinical and angiographic characteristics and procedural outcomes of 636 patients who underwent CTO PCI at 6 high-volume centres in the United States between January 2012 and March 2014.', 'The CTO target vessel was the RCA in 387 cases (61%), LAD in 132 (21%), and LCX in 117 (18%). LCX lesions were more tortuous and RCA lesions had greater occlusion length and Japanese Chronic Total Occlusion (J-CTO) score, but were less likely to have a side branch at the proximal cap and had more developed collateral circulation. The rate of procedural success was lower in LCX CTOs (84.6%), followed by RCA (91.7%), and LAD (94.7%) CTOs (P = 0.016). Major complications tended to occur more frequently in LCX PCI (4.3% vs 1.0% for RCA vs 2.3% for LAD; P = 0.07). LCX and RCA CTO PCI required longer fluoroscopy times (45 [interquartile range (IQR), 30-74] minutes vs 45 [IQR, 21-69] minutes for RCA vs 34 [IQR, 20-60] minutes for LAD; P = 0.018) and LCX CTOs required more contrast administration (280 [IQR, 210-370] mL vs 250 [IQR, 184-350] mL for RCA and 280 [IQR, 200-400] mL for LAD).\Question: Is percutaneous intervention of circumflex chronic total occlusions associated with worse procedural outcomes : insights from a Multicentre US Registry?
[A]: In a contemporary, multicentre CTO PCI registry, LCX was the least common target vessel. Compared with LAD and RCA, PCI of LCX CTOs was associated with a lower rate of procedural success, less efficiency, and a nonsignificant trend for higher rates of complications.


[Q]: Context: Although the C5 variant of cholinesterase is known to be a cause of hypercholinesterasemia, the pathophysiological significance of the C5 variant and the C5 variant-related hypercholinesterasemia in cardiovascular diseases remain unclear. The present study aimed to clarify the pathophysiological significance of the C5 variant as a risk or protective factor for coronary artery disease (CAD) in patients with severe hypercholinesterasemia.', 'Severe hypercholinesterasemia was defined as serum cholinesterase (ChE) activity >= 450 IU/L (>= 2.0 SD). We screened 11,648 consecutive outpatients between 2005 and 2011 at Toho University, Sakura Medical Center. In patients with severe hypercholinesterasemia, phenotyping of the C5 variant was conducted using polyacrylamide gel electrophoresis and alpha-naphthyl butyrate staining.', '157 subjects (1.4% of 11,648 outpatients screened) were diagnosed with severe hypercholinesterasemia (mean serum ChE activity 574 ± 109 IU/L), and the frequency of the C5 variant was 45.2%. Subjects with the C5 variant had higher age, lower body mass index, milder dyslipidemia and liver dysfunction, and lower rates of hypertension and CAD compared with subjects without the C5 variant. Multivariate logistic regression model demonstrated that the presence of C5 variant independently lowered the risk of CAD, with odds ratio 0.071 (95% confidence interval (CI) 0.007 - 0.763, p = 0.029).\Question: Is c5 variant associated with decreased risk of coronary artery disease in outpatients with severe hypercholinesterasemia?
[A]: The prevalence of the C5 variant was relatively high, and the C5 variant is associated with decreased risk of CAD in outpatients with severe hypercholinesterasemia.


[Q]: Context: Next-generation sequencing (NGS) allows for sampling numerous viral variants from infected patients. This provides a novel opportunity to represent and study the mutational landscape of Hepatitis C Virus (HCV) within a single host.', 'Intra-host variants of the HCV E1/E2 region were extensively sampled from 58 chronically infected patients. After NGS error correction, the average number of reads and variants obtained from each sample were 3202 and 464, respectively. The distance between each pair of variants was calculated and networks were created for each patient, where each node is a variant and two nodes are connected by a link if the nucleotide distance between them is 1. The work focused on large components having > 5% of all reads, which in average account for 93.7% of all reads found in a patient.\Question: Does next-generation sequencing reveal large connected networks of intra-host HCV variants?
[A]:
Most intra-host variants are organized into distinct single-mutation components that are: well separated from each other, represent genetic distances between viral variants, robust to sampling, reproducible and likely seeded during transmission events. Facilitated by NGS, large components offer a novel evolutionary framework for genetic analysis of intra-host viral populations and understanding transmission, immune escape and drug resistance.