Patient Portal; Home/ Services/ Cardiology. ... Northwest Cardiology - Siloam Springs 603-2 N. Progress Ave., Suite 400 Siloam Springs, AR 72761. Pahul Singh, M.D. Cardiology (479) 553-2200. Northwest Cardiology - Bentonville 2900 Medical Center Pkwy., Suite 240B Bentonville, AR 72712.Providers‧For Patients.