Atrial tachycardia is a supraventricular tachycardia (SVT) that does not require the atrioventricular (AV) junction, accessory pathways, or ventricular tissue for its initiation and maintenance.
Page Content. Northern Natural Gas Company (Northern) is a subsidiary of Berkshire Hathaway Energy based in Omaha, Nebraska and has been in business since 1930. Northern owns and operates the largest interstate natural gas pipeline system in the United States.
As of January 2015, Exxon Mobil is the largest producer of natural gas in the United States at 3,415 million cubic feet per day, according to the Natural Gas Supply Association. Next is Chesapeake Energy at 2,979 million cubic feet per day, followed by Anadarko and Southwestern Energy Co.