A 48-year old male with a past medical history of hypertensionpresented his physician with complaints of chest pain (6/10 where10 = strongest pain) and shortness of breath that began the priorevening while playing softball. At the time of presentation, hissymptoms were also associated with nausea and vomiting which thepatient attributed to acid reflux. An ECG done at in thephysician’s office and showed ST elevations.
1. Based on the patient’s medical history presentingsymptoms, which clinical condition was his chest pain was MOSTLIKELY attributable to: stable angina pectoris or unstable angina?EXPLAIN your rationale for the answer
Due to the ECG results, the patient was referred to theEmergency Department at the local hospital (Hospital A) for furtherevaluation where a cardiac catheterization was performed andrevealed 100% proximal occlusion of the left anterior descendingcoronary artery.
Due to the results of the catheterization, the patient wassubsequently transferred to the nearest academic medical center(Hospital B) for further evaluation and treatment. Initialtreatment at Hospital B included another catheterization duringwhich a thrombosis was removed and three drug eluding stents wereplaced. The laboratory was asked to perform the following cardiactests during the patient’s stay:
Date; Time |
Troponin I (ng/mL) |
CK (IU/L) |
CK-MB (ng/mL) |
CK-RI |
7/7; 6:30 pm |
>100* |
10948, 9989 |
638 |
5.8 |
7/8; 2:00 am |
>100* |
8559 |
399 |
4.7 |
7/8; 9:25 am |
>97* |
5750 |
230 |
4.0 |
7/8; 2:55 pm |
>97* |
– |
– |
– |
7/8; 10:30 pm |
84 |
– |
– |
– |
7/9; 4:30 pm |
75 |
– |
– |
– |
7/11; 3:30 am |
32 |
866 |
– |
– |
* : Troponin I levels were reported to the highest calibratedconcentration CK: Creatine Kinase CK-MB: Creatine Kinase-Muscle/Brain isoform CK-RI: Creatine Kinase Relative Index [(CK-MB/CK) x 100] – : Test not ordered at this time |
2. Has the patient definitively had a myocardialinfarction (MI) OR is there another possible explanation for theelevation in the test results? Explain your answer
The instrument used to perform the above tests was not accuratewhen dilutions of the original sample were run and results of theoriginal sample were above the linearity of the assay. Thus, thecurrent sample and all subsequent samples were sent to the lab atHospital C for them to perform the assays which utilized adifferent platform that allowed for serial dilutions. (Bottomtable)
Date; Time |
Troponin I (ng/mL) |
CK (IU/L) |
CK-MB (ng/mL) |
CK-RI |
7/7; 6:30 pm |
362 |
11,453 |
544 |
4.7 |
7/8; 2:00 am |
163 |
7,987 / 7896 |
296 |
3.7 |
7/8; 9:25 am |
117 |
6,675 |
186 |
2.8 |
CK: Creatine Kinase CK-MB: Creatine Kinase-Muscle/Brain isoform CK-RI: Creatine Kinase Relative Index [(CK-MB/CK) x100] |
4. What does the Creatine Kinase Relative Index resulttell the physician about the patient’s clinical condition? (1point)
Another male (60 y/o) at the same softball game collapsed withsevere chest pain and shortness of breath. An ambulance was calledand the man was taken to the Emergency Department of Hospital A. Ablood specimen was drawn from the patient upon arrival in the ED.When the results came back from the lab, all of the enzymeactivities were within the “normal” reference range.
5. What is the MOST LIKELYexplanation for the results?
6. What other tests should be ordered that wouldprobably give you a clearer picture that he may have had anMI?