Diseases of the Circulatory System: (ICD-10-CM Chapter 9, Codes I00-I99)

Diseases of the Circulatory System

(ICD-10-CM Chapter 9, Codes I00-I99)

Learning Objectives

Abbreviations/Acronyms

ACS acute coronary syndrome

AF atrial fibrillation

AICD automatic implantable cardioverter-defibrillator

AIDS acquired immunodeficiency syndrome

AMI acute myocardial infarction

AV atrioventricular

AVM arteriovenous malformation

AVR aortic valve replacement

BNP brain natriuretic peptide

BP blood pressure

CAB coronary artery bypass

CABG coronary artery bypass graft

CAD coronary artery disease

CAT computerized axial tomography

CCU coronary care unit

CHB complete heart block

CHF congestive heart failure

CKD chronic kidney disease

COPD chronic obstructive pulmonary disease

CPK creatine phosphokinase

CPK-MB creatine phosphokinase, isoenzyme MB

CRT cardiac resynchronization therapy

CRT-D cardiac resynchronization treatment defibrillator

CRT-P cardiac resynchronization treatment pacemaker

CT computerized tomography

CVA cerebrovascular accident

CVL central venous line

CXR chest x-ray

DES drug-eluting stent

DOE dyspnea on exertion

DM diabetes mellitus

DVT deep vein thrombosis

EKG/ECG electrocardiogram

EP electrophysiologic

ER Emergency Room

HCVD hypertensive cardiovascular disease

HTN hypertension

ICD internal cardiac defibrillator

ICD-9-CM International Classification of Diseases, 9th Revision, Clinical Modification

ICD-10-CM International Classification of Diseases, 10th Revision, Clinical Modification

ICD-10-PCS International Classification of Diseases, 10th Revision, Procedure Coding System

ICV implantable cardioverter

IV intravenous

IVDU intravenous drug user

LAD left anterior descending

LCA left coronary artery

MI myocardial infarction

MRI magnetic resonance imaging

MS-DRG Medicare Severity diagnosis-related group

MUGA multiple-gated acquisition

MVR mitral valve replacement

NQMI non–Q wave myocardial infarction

NSTEMI non–ST elevation myocardial infarction

OM obtuse marginal

OSA obstructive sleep apnea

PCI percutaneous coronary intervention

PDA posterior descending artery

PHT pulmonary hypertension

PICC peripherally inserted central catheter

PPH primary pulmonary hypertension

PTCA percutaneous transluminal coronary angioplasty

RA right atrium

RBBB right bundle branch block

RCA right coronary artery

RFA radiofrequency ablation

RHD rheumatic heart disease

RW relative weight

SOB shortness of breath

SSS sick sinus syndrome

STEMI ST elevation myocardial infarction

SVT supraventricular tachycardia

TIA transient ischemic attack

TPA tissue plasminogen activator

TPN total parenteral nutrition

USA unstable angina

ICD-10-CM Official Guidelines for Coding and Reporting

Please refer to the companion Evolve website for the most current guidelines.

9. Chapter 9: Diseases of Circulatory System (I00-I99)

a. Hypertension

1) Hypertension with Heart DiseaseHeart conditions classified to I50.- or I51.4-I51.9, are assigned to, a code from category I11, Hypertensive heart disease, when a causal relationship is stated (due to hypertension) or implied (hypertensive). Use an additional code from category I50, Heart failure, to identify the type of heart failure in those patients with heart failure.The same heart conditions (I50.-, I51.4-I51.9) with hypertension, but without a stated causal relationship, are coded separately. Sequence according to the circumstances of the admission/encounter.

Example

Congestive heart failure due to hypertensive heart disease, I11.0, I50.9.

Example

Congestive heart failure in a patient with hypertension, I50.9, I10.

2) Hypertensive Chronic Kidney DiseaseAssign codes from category I12, Hypertensive chronic kidney disease, when both hypertension and a condition classifiable to category N18, Chronic kidney disease (CKD), are present. Unlike hypertension with heart disease, ICD-10-CM presumes a cause-and-effect relationship and classifies chronic kidney disease with hypertension as hypertensive chronic kidney disease.The appropriate code from category N18 should be used as a secondary code with a code from category I12 to identify the stage of chronic kidney disease.See Section I.C.14. Chronic kidney disease.If a patient has hypertensive chronic kidney disease and acute renal failure, an additional code for the acute renal failure is required.

Example

The patient was admitted with acute renal failure. The patient was given secondary diagnoses of benign hypertension and chronic kidney disease, stage III, N17.9, I12.9, N18.3.

3) Hypertensive Heart and Chronic Kidney DiseaseAssign codes from combination category I13, Hypertensive heart and chronic kidney disease, when both hypertensive kidney disease and hypertensive heart disease are stated in the diagnosis. Assume a relationship between the hypertension and the chronic kidney disease, whether or not the condition is so designated. If heart failure is present, assign an additional code from category I50 to identify the type of heart failure.The appropriate code from category N18, Chronic kidney disease, should be used as a secondary code with a code from category I13 to identify the stage of chronic kidney disease.See Section I.C.14. Chronic kidney disease.The codes in category I13, Hypertensive heart and chronic kidney disease, are combination codes that include hypertension, heart disease and chronic kidney disease. The Includes note at I13 specifies that the conditions included at I11 and I12 are included together in I13. If a patient has hypertension, heart disease and chronic kidney disease then a code from I13 should be used, not individual codes for hypertension, heart disease and chronic kidney disease, or codes from I11 or I12.For patients with both acute renal failure and chronic kidney disease an additional code for acute renal failure is required.

Example

Patient has stage III chronic kidney disease. They are admitted with acute on chronic diastolic congestive heart failure which is hypertensive in nature, I13.0, 150.33, N18.3.

4) Hypertensive Cerebrovascular DiseaseFor hypertensive cerebrovascular disease, first assign the appropriate code from categories I60-I69, followed by the appropriate hypertension code.

Example

Cerebrovascular accident in a patient with malignant hypertension, I63.9, I10.

5) Hypertensive RetinopathySubcategory H35.0, Background retinopathy and retinal vascular changes, should be used with a code from category I10 – I15, Hypertensive disease to include the systemic hypertension. The sequencing is based on the reason for the encounter.

Example

The patient is being treated for bilateral retinopathy due to labile hypertension, H35.033, I10.

6) Hypertension, SecondarySecondary hypertension is due to an underlying condition. Two codes are required: one to identify the underlying etiology and one from category I15 to identify the hypertension. Sequencing of codes is determined by the reason for admission/encounter.

Example

Hypertension due to periarteritis nodosa, M30.0, I15.8.

7) Hypertension, TransientAssign code R03.0, Elevated blood pressure reading without diagnosis of hypertension, unless patient has an established diagnosis of hypertension. Assign code O13.-, Gestational [pregnancy-induced] hypertension without significant proteinuria, or O14.-, Pre-eclampsia, for transient hypertension of pregnancy.

Example

The patient has an elevated blood pressure caused by the stress of being in an MVA, R03.0.

8) Hypertension, ControlledThis diagnostic statement usually refers to an existing state of hypertension under control by therapy. Assign the appropriate code from categories I10-I15, Hypertensive diseases.

9) Hypertension, UncontrolledUncontrolled hypertension may refer to untreated hypertension or hypertension not responding to current therapeutic regimen. In either case, assign the appropriate code from categories I10-I15, Hypertensive diseases.

Example

The patient’s benign hypertension has been well controlled since the patient lost 20 pounds and started a regular exercise program, I10.

Example

The patient’s hypertension has been uncontrolled for the past 2 months in spite of changes in medication, I10.

b. Atherosclerotic Coronary Artery Disease and AnginaICD-10-CM has combination codes for atherosclerotic heart disease with angina pectoris. The subcategories for these codes are I25.11, Atherosclerotic heart disease of native coronary artery with angina pectoris and I25.7, Atherosclerosis of coronary artery bypass graft(s) and coronary artery of transplanted heart with angina pectoris.When using one of these combination codes it is not necessary to use an additional code for angina pectoris. A causal relationship can be assumed in a patient with both atherosclerosis and angina pectoris, unless the documentation indicates the angina is due to something other than the atherosclerosis.If a patient with coronary artery disease is admitted due to an acute myocardial infarction (AMI), the AMI should be sequenced before the coronary artery disease.See Section I.C.9. Acute myocardial infarction (AMI)

Example

Patient with a previous coronary artery bypass is admitted with unstable angina. It is determined that the patient’s angina is due to a blockage in the bypass grafts, I25.700.

c. Intraoperative and Postprocedural Cerebrovascular AccidentMedical record documentation should clearly specify the cause- and-effect relationship between the medical intervention and the cerebrovascular accident in order to assign a code for intraoperative or postprocedural cerebrovascular accident.Proper code assignment depends on whether it was an infarction or hemorrhage and whether it occurred intraoperatively or postoperatively. If it was a cerebral hemorrhage, code assignment depends on the type of procedure performed.

Example

The patient had a postoperative cerebrovascular accident, which was embolic in nature. The patient had initially been admitted for treatment of coronary artery arteriosclerosis with CABG (left internal mammary artery and two open saphenous vein grafts from the left greater saphenous vein were used). Cardiopulmonary bypass was used during the surgery. I25.10, I97.820, I63.40, 021109W, 02100A9, 5A1221Z, 06BQ0ZZ.

d. Sequelae of Cerebrovascular Disease

1) Category I69, Sequelae of Cerebrovascular diseaseCategory I69 is used to indicate conditions classifiable to categories I60-I67 as the causes of sequela (neurologic deficits), themselves classified elsewhere. These “late effects” include neurologic deficits that persist after initial onset of conditions classifiable to categories I60-I67. The neurologic deficits caused by cerebrovascular disease may be present from the onset or may arise at any time after the onset of the condition classifiable to categories I60-I67.Codes from category I69, Sequelae of cerebrovascular disease, that specify hemiplegia, hemiparesi, and monoplegia identify whether the dominant or nondominant side is affected. Should the affected side be documented but not specified as dominant or nondominant, and the classification system does not indicate a default, code selection is as follows:

• For ambidextrous patients, the default should be dominant.

• If the left side is affected, the default is non-dominant.

• If the right side is affected, the default is dominant.

2) Codes from category I69 with codes from I60-I67Codes from category I69 may be assigned on a health care record with codes from I60-I67, if the patient has a current cerebrovascular disease and deficits from an old cerebrovascular disease.

3) Codes from category I69 and Personal history of transient ischemic attack (TIA) and cerebral infarction (Z86.73)Codes from category I69 should not be assigned if the patient does not have neurologic deficits.See Section I.C.21. 4. History (of) for use of personal history codes

Example

Aphasia due to cerebrovascular accident 3 months ago, I69.320.

Example

The patient was admitted with left-sided hemiparesis due to a cerebrovascular accident. The patient has a history of previous CVA with residual facial droop, I63.9, G81.94, I69.392.

Example

The patient had a CVA in 2002 with no residuals, Z86.73.

e. Acute myocardial infarction (AMI)

1) ST elevation myocardial infarction (STEMI) and non ST elevation myocardial infarction (NSTEMI)The ICD-10-CM codes for acute myocardial infarction (AMI) identify the site, such as anterolateral wall or true posterior wall. Subcategories I21.0-I21.2 and code I21.4 are used for ST elevation myocardial infarction (STEMI). Code I21.4, Non-ST elevation (NSTEMI) myocardial infarction, is used for non ST elevation myocardial infarction (NSTEMI) and nontransmural MIs.If NSTEMI evolves to STEMI, assign the STEMI code. If STEMI converts to NSTEMI due to thrombolytic therapy, it is still coded as STEMI.For encounters occurring while the myocardial infarction is equal to, or less than, four weeks old, including transfers to another acute setting or a postacute setting, and the patient requires continued care for the myocardial infarction, codes from category I21 may continue to be reported. For encounters after the 4 week time frame and the patient is still receiving care related to the myocardial infarction, the appropriate aftercare code should be assigned, rather than a code from category I21. For old or healed myocardial infarctions not requiring further care, code I25.2, Old myocardial infarction, may be assigned.

Example

The patient was admitted with NSTEMI, I21.4.

Example

The patient was admitted with anterolateral wall STEMI, I21.09.

2) Acute myocardial infarction, unspecifiedCode I21.3, ST elevation (STEMI) myocardial infarction of unspecified site, is the default for the unspecified term acute myocardial infarction. If only STEMI or transmural MI without the site is documented, query the provider as to the site, or assign code I21.3.

3) AMI documented as nontransmural or subendocardial but site providedIf an AMI is documented as nontransmural or subendocardial, but the site is provided, it is still coded as a subendocardial AMI. If NSTEMI evolves to STEMI, assign the STEMI code. If STEMI converts to NSTEMI due to thrombolytic therapy, it is still coded as STEMI.See Section I.C.21.3 for information on coding status post administration of tPA in a different facility within the last 24 hours.

Example

Patient is admitted with an NSTEMI of the anterolateral wall, I21.4.

4) Subsequent acute myocardial infarctionA code from category I22, Subsequent ST elevation (STEMI) and non ST elevation (NSTEMI) myocardial infarction, is to be used when a patient who has suffered an AMI has a new AMI within the 4 week time frame of the initial AMI. A code from category I22 must be used in conjunction with a code from category I21. The sequencing of the I22 and I21 codes depends on the circumstances of the encounter.

Example

Patient is admitted with an STEMI of the anterolateral wall. During initial recovery in the hospital, the patient experiences a subsequent NSTEMI, I21.09, I22.2.

Example

Patient was discharged 3 weeks ago following an inferolateral STEMI. She presents today with unstable angina determined to be a posterolateral MI, I22.8, I21.19.

Apply the General Coding Guidelines as found in Chapter 5 and the Procedural Coding Guidelines as found in Chapters 6 and 7.

Anatomy and Physiology

The circulatory system is composed of the heart and blood vessels (Figure 15-1). Its function is to supply tissue in the body with oxygen and nutrients. This function is accomplished when the arteries carry blood (oxygen) to the cells. The largest artery, the aorta, branches off the heart and divides into many smaller arteries. The veins carry deoxygenated blood to the lungs to acquire oxygen and then to the heart, which pumps oxygenated blood back to the arteries.

The Heart

The function of the heart is to pump oxygen-rich blood to the cells of the body. The heart itself receives oxygenated blood from the coronary arteries; the two major coronary arteries branch off the aorta.

The heart is enclosed laterally by the lungs, posteriorly by the backbone, and anteriorly by the sternum. The wall of the heart is composed of three layers: epicardium, myocardium, and endocardium (Figure 15-2). The epicardium is the outer protective layer, the myocardium is the middle layer and is composed of cardiac muscle, and the endocardium is the inner layer that lines all the heart chambers and covers the heart valves.

The heart consists of four chambers: right atrium, left atrium, right ventricle, and left ventricle. The atrium and the ventricle on the right side are separated from the left by a septum. The top two chambers, the atria, receive blood via the veins from the body or the lungs. The right ventricle pumps blood to the lungs to pick up oxygen, and the left ventricle pumps blood to the rest of the body. Within the heart are four valves (Figure 15-3), and their job is to direct blood flow. The tricuspid valve is located between the right atrium and the right ventricle. The valve between the left atrium and the left ventricle is the mitral or bicuspid valve. The aortic valve is located in the aorta at the point at which the left ventricle empties into the aorta. The pulmonary valve is located in the pulmonary artery at the point of exit from the right ventricle.

image
FIGURE 15-3 Cardiac valves.

Blood Vessels

Blood vessels are the tubes that transport blood from the heart to the cells and back to the heart. Most arteries (Figure 15-4) carry oxygenated blood away from the heart. They continue to get smaller the farther away they are from the heart (arterioles). At this point, arterioles lead to capillaries, and exchange is made between blood and body cells; venules and veins (Figure 15-5) return blood back to the heart. The circulation of blood that moves throughout the body is referred to as systemic circulation. Blood pressure measured at the arm indicates systemic pressures.

image
FIGURE 15-4 The arteries.

Lymphatic System

The lymphatic system is closely related to the circulatory system. The lymphatic drainage system returns back to the bloodstream products that have leaked out from the capillaries. The lymph system is made up of lymph nodes, as well as spleen, thymus, tonsils, and adenoids. The lymph system fights infection by filtering out viruses and bacteria by attacking them with lymphocytes.

Disease Conditions

Diseases of the Circulatory System (I00-I99), Chapter 9 in the ICD-10-CM code book, is divided into the following categories:

CATEGORY SECTION TITLES
I00-I02 Acute rheumatic fever
I05-I09 Chronic rheumatic heart disease
I10-I15 Hypertensive diseases
I20-I25 Ischemic heart diseases
I26-I28 Pulmonary heart disease and diseases of pulmonary circulation
I30-I52 Other forms of heart disease
I60-I69 Cerebrovascular diseases
I70-I79 Diseases of arteries, arterioles, and capillaries
I80-I89 Diseases of veins, lymphatic vessels, and lymph nodes, not elsewhere classified
I95-I99 Other and unspecified disorders of the circulatory system

Acute Rheumatic Fever (I00-I02) and Chronic Rheumatic Heart Disease (I05-I09)

Acute rheumatic fever is an inflammatory disease usually found in children that may affect the heart, joints, skin, or brain following an infection with streptococcal bacteria such as strep throat or scarlet fever.

Example

Patient was admitted with acute rheumatic fever with endocarditis, I01.1.

Example

Patient has rheumatic chorea without heart involvement, I02.9.

Chronic rheumatic heart disease is a chronic condition that is usually a late effect of attacks of acute rheumatic fever and most often involves the heart valves. When mitral and aortic valves are involved, ICD-10-CM assumes a causal relationship to rheumatic heart disease unless specified as nonrheumatic. ICD-10-CM also presumes a causal relationship for certain mitral valve disorders of unspecified etiology. Tricuspid valve disorders are assumed rheumatic unless specified as nonrheumatic in origin (Figure 15-6).

Example

Stenosis, mitral, I05.0.

Hypertensive Diseases (I10-I15)

Hypertension is classified as primary (essential) or secondary. Primary hypertension, or high blood pressure (BP), is a condition that is defined as abnormally high blood pressure in the arterial system. The American Heart Association defines hypertension as pressures exceeding 140/90. A diagnosis of hypertension can be made only by a physician and should not be assigned on the basis of BP readings alone. Essential hypertension has no known origin, and its symptoms are insidious.

Secondary hypertension is a consequence of other diseases such as kidney diseases, brain tumor, or polycythemia. When secondary hypertension is documented, two codes are required. The additional code required for secondary hypertension is the underlying condition code. The sequencing of these two codes depends on the circumstances of the admission.

Example

Patient is admitted with hypercalcemia due to hyperparathyroidism. The patient also has hypertension due to the hyperparathyroidism, E21.3, I15.2.

Example

Patient has hypertension due to Cushing’s disease, E24.9, I15.2.

Medications often used for treating hypertension include Accupril, Aldomet, captopril, Cardizem, diltiazem, Cozaar, losartan, Coreg, dyazide, Hytrin, Inderal, Lopressor, Norvasc, Procardia, Tenormin, atenolol, Vasotec, Toprol, Calan, verapamil, Zestril, and lisinopril.

Example

Patient has a past history of hypertension, currently taking verapamil, I10.

For a variety of reasons, patients may have elevated blood pressure readings. Unless a patient has an established diagnosis of hypertension, the code R03.0 elevated blood pressure, should be assigned.

Example

The patient has high blood pressure; will recheck at next clinic visit. No medications were given, R03.0.

Hypertensive Heart, Renal, and Heart and Renal Disease

ICD-10-CM assumes a cause-and-effect relationship and classifies chronic kidney disease with hypertension as hypertensive renal disease. This indicates to the coder that any time hypertension and chronic kidney disease (codes from category N18) occur in a patient, category (I12) should be assigned. The only time the (I12) category code would not be selected is when the physician documents CKD not due to hypertension. On occasion, a patient will have CKD due to diabetes and also have hypertension; diabetic kidney disease and hypertensive kidney disease would both be assigned in these cases.

Hypertensive heart disease, in contrast to hypertensive renal disease, does not assume a cause-and-effect relationship. A causal relationship must be stated by the physician. For a code from this category to be assigned, the physician must document hypertensive heart disease or must say that heart disease is due to hypertension. It is important to note that if a patient has hypertensive congestive heart failure, at least two codes—I11.0 and I50.- —are required; if known, the codes for systolic (I50.2-), diastolic (I50.3-), or a combination systolic and diastolic (I50.4-) should also be assigned.

Example

Patient is admitted with both diastolic and systolic congestive heart failure due to long history of hypertension, I11.0, I50.40.

Hypertensive heart and renal disease requires that the condition be classified to I13.–. It is important to become familiar with the Includes as well as Excludes notes in all of the above categories. It is also important to note that if a patient also has acute renal failure with any of the above conditions, an additional code for the acute renal failure is also assigned.

Example

Patient is admitted with hypertensive renal disease. The patient also has hypertensive cardiomyopathy, I13.10, N18.9.

Exercise 15-1

Assign codes to the following conditions.

1.  Patient is admitted with a diagnosis of hypertensive urgency _______________
2.  Aortic stenosis with mitral insufficiency _______________
3.  Malignant hypertension _______________
4.  Labile hypertension _______________
5.  Portal hypertension _______________
6.  Congestive heart failure due to hypertensive heart disease _______________
7.  Cardiomegaly with hypertension _______________
8.  Hypertension secondary to coarctation of aorta _______________
9.  Ocular hypertension, right eye _______________
10.  Essential hypertension _______________
11.  HCVD (hypertensive cardiovascular disease) with chronic renal failure _______________
12.  High blood pressure reading _______________

Ischemic Heart Disease (I20-I25)

Acute Myocardial Infarction

Acute myocardial infarction (AMI, or MI) in layman’s terms is known as a heart attack. An MI occurs when complete blockage of blood flow occurs in a coronary artery. When this occurs, blood is prevented from reaching the heart muscle (Figure 15-7). Blockage may be caused by fatty deposits (also known as plaque or atherosclerosis) or blood clots. When the blood cannot reach the heart, the heart muscle may become damaged. Signs of a heart attack include chest pain, shortness of breath, nausea, and pain in the arms and chest.

To determine whether a patient is having a heart attack, several tests, including various types of blood tests, may be performed. One of these tests is called CPK (creatine phosphokinase, or creatine kinase). CPK is an isoenzyme that occurs in high concentration in the heart and skeletal muscle. The level of CPK-MB (creatine phosphokinase, MB isoenzyme) in the blood rises 3 to 6 hours after an MI and returns to normal 12 to 48 hours after the infarct. Usually, CPK is measured every 8 to 12 hours, and patterns are determined. The normal value for males is 25 to 90; for females, it is 10 to 70. Another type of blood test that is often performed is the measurement of cardiac muscle proteins called troponins. Testing for troponin levels and CPK levels is performed serially. Troponin levels are usually very low, and elevated levels can indicate damage to the heart. Healthcare providers also perform electrocardiograms (EKGs) to determine whether an MI has occurred.

Types of MI may be classified as to the area of heart that suffers damage or the extent of damage, as evidenced by an EKG (Figure 15-8). The most common areas are the following:

STEMI (ST elevation MI) occurs when complete obstruction of the coronary artery causes damage involving the full thickness of the heart muscle. This type of MI is also known as an ST elevation MI or a Q wave MI. NSTEMI (non–ST elevation) occurs when a coronary artery is partially obstructed and damage does not involve the full thickness of the heart muscle. This type of MI is often referred to as non–Q wave MI. Old terminology for transmural or nontransmural MI has been replaced by Q or non–Q MI.

Patients suspected of having an MI are usually treated with a combination of medications and/or procedures. Procedures performed to treat the causes of MI include coronary angioplasty (percutaneous transluminal coronary angioplasty [PTCA]), stenting (percutaneous coronary intervention [PCI]), and possibly coronary artery bypass surgery (CABG or CAB). Often, upon presentation of the patient to the Emergency Room (ER), thrombolytic therapy is initiated. Thrombolytics (tissue plasminogen activator [TPA], streptokinase) are used to dissolve blood clots that may be blocking a coronary artery. Thrombolytics must be administered within 6 hours of the onset of chest pain to avoid heart damage. A potential adverse effect of the use of these drugs is severe bleeding; for this reason, they are contraindicated in many patients. All of these procedures are discussed in greater detail in the procedure section of this chapter.

When assigning a code for an acute MI in ICD-10-CM, it is important to find documentation of the site of the MI for a STEMI. It is also important to note that a code from I21 is assigned for an MI that has occurred within 28 days of the current admission. If the MI is older than 28 days, then code I25.2 is assigned.

Example

Patient was admitted with NSTEMI, I21.4.

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Jun 3, 2017 | Posted by in GENERAL SURGERY | Comments Off on Diseases of the Circulatory System: (ICD-10-CM Chapter 9, Codes I00-I99)

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