a. The diagnosis of "high blood pressure" is classified to category 41 (Ess ential
b. The diagnosis of "elevated blood pressure" without the term "hypertension" is
classified to code 796.2 (elevated blood pressure reading without diagnosis of
8. Most cases of chronic valvular heart disease are acquired and due to a previous
attack of acute rheumatic fever (usually unrecognized) resulting in stenosis or
incompetence of the valves. The mitral valves are the most commonly affected. In
ICD-9-CM, some of these resultant disorders of the mitral valve are classified to the
section on rheumatic diseases, while others are not, unless the diagnosis specifies the
condition as rheumatic. Disorders of the aortic valve must be specified as rheumatic in
order to be classified to section 396. When both the mitral and aortic valves are
involved, whether specified or not, the condition is classified to code 396, the section on
9. Ischemic heart disease occurs as a result of the lack of blood flow to the heart due
to partial or complete obstruction of the coronary artery. This disease may be identified
by such terms as arteriosclerotic heart disease, coronary ischemia, or coronary artery
disease. Sequencing of this disease depends on the reason for admission. When
hypertension is present as a secondary condition to ischemic heart disease, sequence
the ischemic heart disease before the hypertension code.
10. The diagnosis arteriosclerotic cardiovascular disease (ASCVD) requires two codes.
Code 429.2 identifies the cardiovascular disease but does not identify it as being due to
arteriosclerosis (code 44.9). The correct codes for ASCVD are 429.2 and 44.9. The
exclusion note under 44.9. should be interpreted as "use additional code" to identify
the site of the arteriosclerosis (cardiovascular). It is not specified in code 44.9.
11. When assigning codes to complications of surgical care resulting from surgery, the
"excludes" note under code 997.1 needs clarification of the term "long-term."
a. Subcategory 997.1 classifies cardiac complications that occur during the
immediate postoperative period or during the continuous period of hospitalization in
which the surgery was performed.
b. Subcategory 429.4 classifies "long-term" cardiac complications resulting from
cardiac surgery performed during a previous episode of care, regardless of the time-
span between the surgery and the complications.
c. Subcategory 997.1 is used also to classify immediate cardiac complications
resulting from any type of procedure. Subcategory 429.4 is used to classify "long-term"
cardiac complications resulting from cardiac surgery only. The surgery must have been
performed during a previous episode of care.
d. Subcategory 996.43 is used to classify occlusion of coronary artery bypass
grafts over a period of time (no specific time limits.).