DRG 321 Overview

DRG 321 covers percutaneous cardiovascular procedures involving placement of intraluminal devices with a Major Complication or Comorbidity or interventions involving four or more arteries or intraluminal devices. Typical cases include complex percutaneous coronary interventions with multiple stents or other endovascular devices accompanied by significant comorbidity. This Diagnosis-Related Group is important for Medicare payment because it captures higher-resource, higher-risk inpatient encounters that affect reimbursement levels. Understanding the clinical scope helps clarify payment categorization and hospital case-mix implications.

Across payers the observed rate range spans from about $21K (BCBS mean) up to $44K (Cigna mean), with individual payer means between $31K and $44K; the widest spread between payer means is approximately $23K. See the table and chart below for percentile detail and distributional context. Full payer labels are shown alongside the numeric benchmarks in the table.

The CMS 2023 data represent national Medicare fee-for-service inpatient payments reported in the CMS Provider Utilization and Payment Data program. The table below shows average total payment, average submitted covered charges, average Medicare payment, and total discharges for DRG 321. These values summarize Medicare payment experience nationally for the DRG in 2023.

• Acute procedural optimization studies assessing percutaneous coronary interventions (PCI) with multiple stents or intraluminal devices in high-risk anatomies: randomized or pragmatic trials focus on intra-procedural strategies (e.g., imaging-guided deployment, adjunctive atherectomy, staged vs. single-session multivessel PCI) among patients presenting with complex coronary disease requiring treatment of four or more arteries or multiple devices. These studies enroll inpatients undergoing index percutaneous cardiovascular procedures and evaluate immediate procedural success, complication rates (bleeding, vessel dissection, distal embolization), and length of stay. Findings inform interventional technique standards and resource utilization that directly affect inpatient costs and DRG-level reimbursement considerations for complex PCI cases.
• Comparative effectiveness research comparing device types and antithrombotic strategies in patients treated with multiple intraluminal devices: observational cohorts or randomized comparative trials examine outcomes for different stent platforms, bioresorbable scaffolds, or adjunctive device use and concurrent antiplatelet/anticoagulant regimens in medically complex patients with multivessel disease. These studies target typical DRG 321 patients who have higher comorbidity burdens (e.g., diabetes, CKD, prior CABG) to assess revascularization durability, repeat revascularization rates, and inpatient adverse events. Results help clinicians and payers evaluate value (clinical benefit vs. cost and complication risk) of specific device and pharmacologic choices in the inpatient setting where device costs and complication-driven expenditures are concentrated.
• Post-discharge outcomes and care-transition studies focused on readmission, rehabilitation, and long-term health resource use after complex percutaneous interventions: cohort studies and pragmatic trials evaluate discharge planning, cardiac rehabilitation referral, medication adherence interventions, and early outpatient follow-up timing for patients who underwent PCI with multiple intraluminal devices. The population includes survivors of complex index procedures whose post-acute care needs and readmission risk are elevated due to extensive revascularization and comorbid conditions; endpoints include 30- and 90-day readmissions, major adverse cardiovascular events, and cumulative post-discharge costs. This area is relevant to providers and payers because reducing readmissions and optimizing post-discharge management can substantially impact total cost of care and quality metrics tied to DRG payments.