Should Treatment of Acute MI be Inpatient? Outpatient? The Codes, the Rules, and the Money

Treating a heart attack as outpatient may sound ludicrous, but for some hospitals it may be the right choice.

The two-midnight rule threw the hospital utilization review community into turmoil when it was implemented on Oct. 1, 2013. In brief, that rule mandates that the decision of whether to enact inpatient admission or outpatient care should be based solely on the expected length of stay, with few exceptions. This posed a dilemma for many hospitals whose care of patients with acute myocardial infarction (MI) had evolved into a well-oiled, protocol-driven machine.

These hospitals had lowered door-to-balloon time for percutaneous coronary intervention well below the 90-minute gold standard and had on staff experienced interventional cardiologists whose successful reperfusion rate was second to none. These patients were then resting comfortable in a hospital bed within a few hours of presentation to the emergency department, and in many cases, they were able to be discharged the next day. That means that if the two-midnight rule was followed to the letter, patients presenting to the emergency department with an ST elevation myocardial infarction (STEMI) who had no comorbid conditions or any evidence of heart failure or arrhythmia were going directly to the cardiac catheterization lab and were expected to be successfully reperfused, treated as outpatients and not admitted as inpatients.

But of course, that was met with skepticism. Did the Centers for Medicare & Medicaid Services (CMS) really expect patients having heart attacks to be treated as outpatients and not admitted to the hospital? We did not get close to a real answer to that question until Jan. 1, 2016, when CMS added to the two-midnight rule a new exception, allowing physicians to determine on a case-by-case basis whether a high-risk patient with an expectation of less than two midnights should be admitted as inpatient. Most interpreted this to mean that patients with a STEMI would fit this exception.

Then CMS added what they thought was a bit more clarity in the 2018 Outpatient Prospective Payment Final Rule by adding CPT® code 92941 to the inpatient-only list for 2018. This code, as cited by CMS, represents “percutaneous transluminal revascularization of acute total/subtotal occlusion during acute myocardial infarction, coronary artery or coronary artery bypass graft, any combination of intracoronary stent, atherectomy and angioplasty, including aspiration thrombectomy when performed, single vessel.” It seemed that settled it; patients with acute MI should all be admitted as inpatients, and in fact, if treated as outpatients and undergoing intervention, the payment should be denied.

But is that correct? Dr. Eddie Hu, the president of the American College of Physician Advisors and system executive director of physician advisor services at UNC Healthcare System, pointed out to me that the CMS definition of 92941 published in the Federal Register is incomplete. CPT 92941 represents placement of a non-drug-eluting stent during acute MI, whereas C9606 is the HCPCS code used by hospital coders that represents placement of a drug-eluting stent during acute MI. That means that most STEMIs, which are treated with drug-eluting stents, would be coded by the hospital as C9606 and are not going to be inpatient-only in 2018.

So if STEMI treated with a drug-eluting stent is not inpatient-only, what status should be chosen? Do we apply the two-midnight expectation or the case-by-case exception? Since the care received by the patient is the same, the decision may actually boil down to a question of finances. From the patient perspective, the status does not matter. The patient with a STEMI who is placed in outpatient and stays one midnight gets the same excellent care that the STEMI patient who is admitted as an inpatient. They have the same physician, would get the same stent, and go to the same room with the same nurse for recovery. In fact, because CMS regulations limit the Part B copayment, the patient’s out-of-pocket costs would be the same.

For the physician, payment for the intervention is independent of the patient’s admission status, except for the fact that the physician must use the place of service on their professional services claim that matches the hospital’s claim, be it inpatient or outpatient. But the cardiologist may also bill for the visit prior to the decision to perform the intervention. In other words, the cardiologist was not called to perform an intervention; he or she was consulted to determine if intervention was warranted, and if so, to arrange for that intervention. That evaluation is billable and will require the physician to choose the appropriate code and apply a modifier. If the patient is an inpatient, the physician would use the initial hospital codes 99221-99223, whereas if outpatient, they would use a code from the 99201-99215 range, which has a lower relative value than those of the inpatient codes. Reimbursement to the physician then would be affected by the admission status.

So what about payment to the hospital? At face value, it would seem that the inpatient admission would pay more. But there are several factors to consider. Since Dr. Hu brought this to my attention, I will use hospitals from his health system and pricing available from the 2017 CMS Inpatient Pricer and Addendum B as an illustration. Since these patients have no comorbid conditions (those with comorbidities such as heart failure, chronic kidney disease, or diabetes would be expected to stay over two midnights and should be admitted as inpatients), if admitted as inpatients, those who received a drug-eluting stent would fall into Diagnosis-Related Group 247. If treated as outpatient, it would fall into C-APC 5194, which is classified as a level 4 endovascular procedure.

For UNC Memorial Hospital, the academic medical center in Chapel Hill, N.C., DRG 247 pays $19,395 and C-APC 5194 pays $14,463, so inpatient admission makes sense, financially speaking. But for Rex Hospital, DRG 247 pays $12,469 and C-APC 5194 pays $14,410. Rex Hospital is being financially harmed by admitting their acute myocardial infarction patients as inpatients.

Why does UNC Memorial Hospital get almost $7,000 more for treating the same inpatient as Rex Hospital? As a teaching hospital, it receives more than $3,000 for indirect medical education. It also receives more than $2,000 for uncompensated and undercompensated care, and almost $1,600 as pass-through and miscellaneous payments. Rex Hospital, on the other hand, although a large hospital, has no formal teaching programs and does not have many patients whose care is uncompensated, so they have no add-ons to their base DRG payment.

What about a location with a higher cost of living, which CMS factors into their payment structure? Let’s look at northern California, where a 2,000-square foot, four-bedroom, two-bathroom house near Apple’s headquarters recently went on the market for $1.8 million and sold for $2.4 million. California Pacific Medical Center-Davies Campus Hospital in San Francisco would be paid $20,279 for DRG 247 and $21,117 for C-APC 5194 – so outpatient acute MI pays better here. But UCSF Medical Center at Parnassas Heights gets $29,727 for DRG 247 (including a whopping $5,800 as an indirect medical education payment) and $21,117 for C-APC 5194. Clearly, UCSF wants their STEMIs admitted as inpatient, but California Pacific would be leaving money on the table by admitting their acute MI patients.

It is clear that the answer here is anything but clear. For some hospitals, the reimbursement is higher for inpatient admission, but for other hospitals, outpatient care has a higher reimbursement. It should also be noted that if a hospital is able to treat an acute MI patient as an outpatient and discharge them, and that patient returns to the hospital within 30 days and requires inpatient admission, the admission would not be a readmission, because there was never a first admission. For hospitals that are being penalized for excess readmissions, it is hard to argue with treating patients as outpatients when they have MI if the hospital gets more money for treating the heart attack and it avoids a possible readmission for the next 30 days.

It should be noted that both admitting an acute MI patient as inpatient and treating them as an outpatient would be compliant with Medicare regulations and the two-midnight rule. And because there is no right or wrong way to status these patients, I will not make any recommendations other than suggest you convene compliance, finance, and utilization review together in the same room and decide what is right for your hospital.