SHERLOCK 3CG™ Diamond Tip Confirmation System

Inclusion Criteria: * Male or female, ≥ 21 years of age with altered cardiac rhythm (no recognizable P-wave on standard ECG) with diagnosis of specific arrhythmia type or identification of pacemaker driven rhythms as defined below: 1. Atrial fibrillation with history of diagnosis per 12-lead ECG in medical record or diagnosed via bedside telemetry by study team RN at assessment, or 2. All other arrhythmias (including but not limited to atrial flutter, PAC, PVC, PJC, tachycardia, AV Block, BB Block) with history of diagnosis per 12-lead ECG in medical record or diagnosed via bedside telemetry by cardiac unit RN at assessment, or retrospectively by site cardiologist, or 3. Pacemaker driven rhythm with temporary or permanent pacemaker device in place; * Subject requires PICC placement as part of standard of care; * Subject or Legally Authorized Representative (LAR) has signed an Informed Consent Form (ICF). Exclusion Criteria: * Subject has a contraindication to PICC placement as listed in the Instructions for Use (IFU) to include: 1. The presence of bacteremia or septicemia (known or suspected), 2. The patient's body size is insufficient to accommodate the size of the implanted device, 3. The patient is known or is suspected to be allergic to materials contained in the device, 4. Past irradiation of prospective insertion site, 5. Previous episodes of venous thrombosis or vascular surgical procedures at the prospective placement site, 6. Local tissue factors will prevent proper device stabilization and/or access; * Subjects who previously had a PICC in place and require a PICC exchange; * Subject has presence of active resting tremor (i.e. Parkinson's, Multiple Sclerosis, etc.) deemed by Investigator to have potential impact on procedure accuracy; * Subjects who are pregnant or think they may be pregnant.