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  5. Complications and ill-defined descriptions of heart disease (I51)

Complications and ill-defined descriptions of heart disease (I51)

The ICD-10 code I51 covers complications and ill-defined descriptions of heart disease, capturing various abnormal conditions that affect the heart but may not fall into more specific categories. These codes are essential for identifying heart issues such as acquired septal defects, ruptures in cardiac structures, myocarditis, cardiomegaly, and other less clearly defined heart diseases.

This group includes detailed conditions like I51.0 for acquired cardiac septal defects, commonly known as traumatic or acquired atrioventricular septal defects, and I51.1 and I51.2 for ruptures of the chordae tendineae and papillary muscles, respectively; key components that maintain heart valve function. I51.3 refers to intracardiac thrombosis, which includes clots within the heart chambers such as atrial or ventricular thrombi. I51.4 codes for unspecified myocarditis, an inflammation of the heart muscle that can involve infectious or immune causes. Cardiomegaly (I51.7) describes enlargement of the heart often associated with hypertrophy or dilatation of cardiac chambers. The section also contains codes for conditions like Takotsubo syndrome (I51.81) and other ill-defined or unspecified heart diseases (I51.8, I51.89, I51.9), facilitating documentation when precise diagnoses are challenging. This coverage helps coders accurately represent complex or uncertain cardiac complications using the ICD-10 code for heart disease complications and ill-defined heart disease.

Instructional Notations

Type 1 Excludes

A type 1 excludes note is a pure excludes note. It means "NOT CODED HERE!" An Excludes1 note indicates that the code excluded should never be used at the same time as the code above the Excludes1 note. An Excludes1 is used when two conditions cannot occur together, such as a congenital form versus an acquired form of the same condition.

Clinical Terms

The following clinical terms provide additional context, helping users better understand the clinical background and common associations for each diagnosis listed in this section. Including related terms alongside ICD-10-CM codes supports coders, billers, and healthcare professionals in improving accuracy, enhancing documentation, and facilitating research or patient education.

Cachexia

General ill health, malnutrition, and weight loss, usually associated with chronic disease.

Cardiomegaly

Enlargement of the HEART, usually indicated by a cardiothoracic ratio above 0.50. Heart enlargement may involve the right, the left, or both HEART VENTRICLES or HEART ATRIA. Cardiomegaly is a nonspecific symptom seen in patients with chronic systolic heart failure (HEART FAILURE) or several forms of CARDIOMYOPATHIES.

Cardiomegaly, Exercise-Induced

Non-pathological heart enlargement and other remodeling in cardiac morphology and electrical circuitry found in individuals who participate in intense repeated exercises.

Cardiotoxicity

Damage to the HEART or its function secondary to exposure to toxic substances such as drugs used in CHEMOTHERAPY; IMMUNOTHERAPY; or RADIATION.

Chagas Cardiomyopathy

A disease of the CARDIAC MUSCLE developed subsequent to the initial protozoan infection by TRYPANOSOMA CRUZI. After infection, less than 10% develop acute illness such as MYOCARDITIS (mostly in children). The disease then enters a latent phase without clinical symptoms until about 20 years later. Myocardial symptoms of advanced CHAGAS DISEASE include conduction defects (HEART BLOCK) and CARDIOMEGALY.

Myocarditis

Inflammatory processes of the muscular walls of the heart (MYOCARDIUM) which result in injury to the cardiac muscle cells (MYOCYTES, CARDIAC). Manifestations range from subclinical to sudden death (DEATH, SUDDEN). Myocarditis in association with cardiac dysfunction is classified as inflammatory CARDIOMYOPATHY usually caused by INFECTION, autoimmune diseases, or responses to toxic substances. Myocarditis is also a common cause of DILATED CARDIOMYOPATHY and other cardiomyopathies.

Takotsubo Cardiomyopathy

A transient left ventricular apical dysfunction or ballooning accompanied by electrocardiographic (ECG) T wave inversions. This abnormality is associated with high levels of CATECHOLAMINES, either administered or endogenously secreted from a tumor or during extreme stress.