Case Summary
A 54-year-old Caucasian male is admitted to the emergency department with chest pain. The patient has a history of tobacco smoking and gastroesophageal reflux (GERD). There was no family history of cardiac
events. An asymptomatic electrocardiogram (ECG) stress test was conducted. Cardiac catheterization and coronary computed tomography angiography
(CCTA) would assist in diagnosing this patient.
Age: 54 years old
Sex: Male
Ethnicity: Caucasian
Medical History
History of tobacco smoking.
No significant family history of cardiac events. BMI 29.
Symptoms
Three weeks of intermediate chest pain, radiating to his left arm and jaw.
Examinations (Clinical Assays/Tests/Imaging)
Physical Examination
Blood pressure of 139/85 mmHg. Heart rate of 81 beats per minute.
The intermediate pretest probability of CAD (coronary artery disease) is based on age and sex.
Electrocardiogram (EKG)
No ischemic changes, no left ventricular hypertrophy or left bundle branch block.
Laboratory Investigations
Serial troponin enzyme < 0.010 ng/mL (normal range: <0.04). Lipid panel showed:
Total cholesterol: 235 mg/dL (normal range: < 200 mg/dL).
Triglycerides: 408 (normal range: <149 mg/dL), HDL: 26 (normal range: < 40 mg/dL) and LDL could not be calculated (normal range: <100 mg/dL).
Electrocardiogram (EKG) Stress Test
Patient achieved 95% of maximum predicted heart rate.
10 METs (metabolic equivalents) of exercise with normalization of T wave (ventricular repolarization) inversions were seen in leads V2 (right ventricle), V3(septum) and V4 (septum)at rest.
Led to maximum asymptomatic stress test results. Intermediate probability of ischemia.
Showed normal left ventricular function with no wall motion or significant valvular abnormalities.
Echocardiogram
Normal left ventricular function and no significant valvular or wall motion abnormalities. Coronary Computed Tomography Angiography (CCTA)
Showed approximate 70% stenosis (narrowing) of origin of the left anterior descending artery (LAD) and noncalcified plaque with an approximate length of 4 mm.
Approximate 40-50% stenosis of proximal ramus intermedius (variant coronary artery) branch secondary to mixed calcified and noncalcified plaque and scattered noncalcified and calcified plaque along obtuse and circumflex marginal branches (branches from the main artery) with luminal diameter stenosis (diameter of permissible blood flow) of approximately 30-40%.
Coronary computed tomography angiography images
Figure 1: Imaging from the coronary computed tomography angiography showing 70% stenosis of “the origin of the left anterior descending artery to secondary to non-calcified plaque extending over a length of approximately 4 mm” (yellow lines).
Fractional Flow Reserve-Computed Tomography (FFR-CT) 1
Results showed a high likelihood of flow-limiting stenosis, less than 0.5 secondary to significant stenosis at LAD origin, with a low likelihood of flow-limiting stenosis in ramus intermedius (variant main coronary artery), right coronary arteries, and left circumflex (branch off left coronary artery).
Cardiac Catheterization
Showed 95% stenotic lesion of LAD with partial perfusion (TIMI grade 2 flow) – penetration without perfusion (incomplete filing of distal coronary bed).
This would give rise to diagonal 1 (a branch from the left anterior descending artery), with an ostial and proximal (narrowing of the ostium) 70% stenosis.
“Ramus intermedius (variant coronary artery) with proximal 70% segmental stenosis”
“Circumflex, nondominant vessel – a mild disease in proximal-distal segments – giving rise to obtuse marginal 1 (on or close to the left obtuse margin of the heart) with proximal 70% stenosis.”
Question & Answers Leading to Diagnosis:
Question 1: Based on the patient’s complaint of recurrent chest pains, EKG and serial troponin test, what could be the possible diagnosis?
Question 2: What investigations could be suggested to confirm this patient’s diagnosis?
Question 3: To characterize further risk stratification for this patient, what other investigations could be done? How would you classify this patient on the TIMI scale?