Objectives for Chest Pain
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Determine the broad differential diagnosis of chest pain including
the life threatening causes of chest pain
Describe the EKG changes associated with acute MI’s and the
coronary arteries involved
Describe the EKG changes associated with the location of an
inferior, lateral and posterior MI
Discuss the risk factors associated with ischemic heart disease
List the initial steps to take in the management of acute chest pain
in the office
USC Case # 6: Chest Pain
A 45 year old white male presents with chief complaint of episodes of recurrent chest
pain. Past medical history is noncontributory. He says the chest pain is like a deep
pressure in the left chest area that is a scale 6/10. It does not radiate and lasts just a few
minutes. It has occurred at rest and with exercise, and occasionally with a big meal. It has
been reoccurring over the last several months. He occasionally gets diaphoretic with the
pain but not always. He also has some dyspnea associated with the chest pain when he
has exercised. He is not currently having pain, and his last epoisode was this morning as
he was shoveling snow off his front walk. What test should you order next without
knowing any further history?
An electrocardiogram. The EKG shows the following:
What is your interpretation of this EKG?
Normal Sinus Rhythm .
Chest pain can often be the presenting symptom of a life threatening condition. What are
five major life threatening diagnoses that you must consider when a patient presents with
chest pain?
Pulmonary embolus
Ischemic heart disease or cardiac problems (e.g. pericarditis, aneurysms)
Pneumothorax
Esophageal rupture
Dissecting aortic aneurysm
If the patient appears to be in distress, obtain O2 saturation and chest x-ray initially in
addition to the EKG.
Clinicians must avoid premature diagnosis of acute coronary syndrome (ACS).
●If acute coronary syndrome (ACS) is the leading diagnosis, initial assessment and
interventions must be performed rapidly to minimize potential injury to the myocardium.
During the initial assessment phase, the following steps should be accomplished for any
patient at significant risk for ACS:
•Airway, breathing, and circulation assessed
Arrange for transfer to emergency Department
•Preliminary history and examination obtained
•12-lead electrocardiogram (ECG) interpreted
•Resuscitation equipment brought to the bedside
•Cardiac monitor attached to patient
•Oxygen given
•IV access and blood work obtained
•Aspirin 162 to 325 mg given
•Nitrates and morphine given (unless contraindicated
●The initial ECG is often NOT diagnostic in patients with ACS. In patients without a clear
diagnosis but at risk for ACS, ECGs may be repeated at frequent intervals (every 10 to 15
minutes) until the patient's chest pain resolves or a definitive diagnosis is made. ECG
assessment is described in the text.
●Certain characteristics of the patient's chest discomfort and associated symptoms increase
the likelihood of ACS, while others make the diagnosis unlikely.. Caution should be
employed in evaluating possible ACS in women, diabetics, and the elderly, who are more
likely to present with "atypical" symptoms even in the presence of acute coronary ischemia.
Of note, relief of symptoms following the administration of therapeutic interventions (eg,
nitroglycerin, "GI cocktail" of viscous lidocaine and antacid) does NOT reliably distinguish
nonischemic from ischemic chest pain.
●The initial physical examination should focus on findings that permit rapid triage and aid in
immediate diagnosis and management.
Initial laboratory work should include: serum cardiac biomarkers (cTnI or cTnT
(troponins) CKMB preferred), CBC with platelet count, PT and INR, PTT, electrolytes,
magnesium, BUN, creatinine, blood glucose, and serum lipid profile.
●Approximately 2 to 4 percent of patients with an ACS are mistakenly discharged from the
office or emergency department; these patients have an increase in short-term mortality.
Patients whose ACS was missed were more likely to be women less than 55 years of age,
non-whites, patients with shortness of breath as the major presenting symptom, and
patients with a normal or nondiagnostic initial ECG.
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The patient appears not to be in distress. He is a good historian and is not presently
having chest pain.
History:
ROS: negative except for chest pain, diaphoresis and dyspnea with exertion.
PMH: tobacco abuse, possibly a high cholesterol taken at a health fair.
PSH: none
FMH: father living with hypertension, mother NIDDM, siblings healthy, maternal
grandfather deceased with stroke, maternal grandmother deceased Alzheimer’s dementia,
paternal grandparents living in their 90’s with good health.
Social hx: married, 2 sons (3,5 y.o.), works as a mechanic, he does not exercise, smokes 2
packs per day for 27 years, drinks 1 beer a month.
Allergies: NKDA
Meds: none
Immunization hx: up to date with last tetanus 2 years ago.
Pain: scale 6/10 left chest deep pressure non-radiating, last 2-3 minutes at rest and
exercise, occasional dyspnea and diaphoresis, no certain things relieve the pain.
Physical Exam
BP 145/95, P 85, R 16, T 98.6, HT 6’0”, WT 265
Gen : Alert and oriented x 3, pleasant, obese.
Skin: warm, moist, pink.
HEENT: normal except for slight A/V nicking and arteriole atherosclerosis on the
Fundoscopic exam.
Heart: regular, rate and rhythm without murmur, no carotid bruits.
Lungs: bilaterally clear to auscultation with decreased breath sounds diffusely.
Abdomen: soft, nontender, normal bowel sounds x 4, no masses, no organomegaly, no
bruits.
Extremities: no cyanosis, no edema, good pulses.
Back: normal
Genitalia: normal
Rectal: heme negative, no masses, prostate soft
Neuro: No focal deficits
Osteopathic: Thoracic T2 SlRr
LABS: CBC: wbc 10.5, hgb 15.5, hct 46.5, platelets 245,000, MCV 95
CMP: glucose 127, remaining normal
Lipid: HDL 20, LDL 185, CHOL 285, TG 325 (all labs fasting)
How many risk factors does he have for heart disease?
Answer: 7
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2.
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7.
High blood pressure
Obesity
Family medical history
Diabetes mellitus (fasting blood sugar greater than 126)
Hyperlipidemia ( elevated chol, low HDL, high LDL, high TG all risks)
Male gender
Tobacco abuse
The patient is referred to a cardiologist to be seen as soon as possible but refuses to
see him till he has a day off which is three weeks away. He is warned of the risk factors
involved of not seeing him in a timely manner. All his risk factors are discussed with
counseling on diet, blood sugar control and smoking. He states he will try to be better,
and refuses any kind of medication because his grandfather took some heart and
cholesterol pills and had problems. The Hgb A1C test for his diabetes is pending at the
time he is discharged. He is instructed not to do any strenuous labor until evaluated by
cardiology with stress testing pending.
Two weeks later the patient presents again with chest pain that will not stop. This time
the pain is a scale 9/10 with a pressure that feels like an elephant sitting on his chest. It
radiates to his left arm and he is very diaphoretic. He denies any dyspnea, but states he is
very nauseated. He started having chest pain at home while digging up a tree. An
ambulance is called for but there is only one in the area and the patient will have to wait
till one can arrive. An intravenous access line is started . An O2 saturation is done
showing 98% saturation on room air and the patient is placed on nasal cannula oxygen at
3 lpm. A chest xray is done which is normal. He has an ekg done which shows the
following.
What’s your diagnosis?
Answer: Acute inferior infarction.
The patient has classic ST-segment elevation in leads II, III and AVF. He appears to
have normal sinus rhythm. There are no Q-waves in these leads, but it is does not have to
be present especially in the early phases of a myocardial infarction. Q-waves usually
coincide with the development of cell necrosis which may occur within hours to days
and persistent on an ekg with loss of the ST segment elevation. 20% of patients
presenting with acute MI have a normal ekg and history should play an important role
determining treatment and testing. 20-30% of patients with acute MI are completely
asymptomatic at the onset of coronary occlusion. Some ST segment changes are seen in
V1, V2 and can occur occasionally with inferior infarcts.
The patient had nausea with the chest pain. Why?
Inferior infarcts involve the inferior portion of the heart which sits on the diaphragm.
Irritation or somato-somatic reflexes could cause nausea and vomiting due to adrenergic
innervation through common pathways.
What’s the sympathetic level of innervation to the heart? What is the parasympathetic
innervation to the heart
T 1-5 (some textbooks state T2-5 on the left) sympathetic.
Vagus nerve parasympathetic.
What artery is most likely to be involved in an inferior infarct? What arteries are
involved in infarcts to other areas of the heart and their ekg changes? What are some of
the ekg changes associated with ischemia?
What laboratory tests would indicate a myocardial infarction?
Troponin appearing in 3-6 hours
CK isoenzymes MB appearing 4-8 hours
LDH within 24 hours and AST
Erythrocyte Sedimentation Rate appearing 3 days after
Leukocytes within several hours and peaking within 2-4 days (if your in a rural area a stat
CBC may give you a hint of possible myocardial infarction)
Risk factors for arteriosclerotic heart disease (ASHD) should be evaluated on every
patient that is seen in an outpatient setting. These should be addressed and treated as
possible. This patient had multiple risk factors with most of them being treatable.
Name some of the risk factors for ASHD?
Risk Factors
-Elevated low density lipoprotein (LDL)
-Decreased high density lipoprotein (HDL)
-Elevated triglycerides
-Smoking
-Family history
-Hypertension
-Diabetes mellitus
-Sedentary lifestyle
-Stress
-Obesity
-Increasing age
-Male sex
-Metabolic syndrome
-Multiple other risk factors with new evidence being found
This patient had multiple risk factors falling under the heading of metabolic syndrome
with many of these factors correctable. A sedentary lifestyle is a major factor for heart
disease and recent studies have shown an obese person who exercises regularly has less
risk than a thin person who lives a sedentary lifestyle.
Diabetes mellitus is a major risk factor for heart disease. Most diabetics die from large
vessel disease. Maintaining an active lifestyle and controlling blood sugar levels with a
Hemoglobin A1C level below 6.5 greatly decreases the risks. Prediabetics probably have
a greater risks and future Hgb A1C levels may be dropped even further.
Hyperlipidemia is a treatable risk factor and should be addressed in every patient who
you see in your office. Recent studies have lowered the LDL levels below 100 and may
possibly be below 70 to reduce the progression of atherosclerosis.
Hypertension is a treatable disease. A systolic pressure below 130 and diastolic below
85 are the only acceptable numbers. The morbidity and mortality increase in a linear
proportion as the blood pressure elevates. The pulse pressure (difference between systolic
and diastolic pressure) is a risk factor for vascular disease and should be addressed
especially in the elderly population, as many elderly believe that only the diastolic
pressure is important as a risk factor.
Smoking risks have been well studied and is a preventable problem if the patient is
willing to quit. Chewing tobacco has risks also as levels of nicotine may be as high as
20X that found with smoking.
There are factors which we have not discovered that contribute to heart disease.
Genetic history appears to contribute greatly to the problem. Some research suggests
inflammation may be a large contributor to heart disease. 50% or greater people who die
from myocardial infarction have normal coronary arteries, and soft plaques or
inflammation may cause thrombosis with secondary infarction. Recent studies also have
shown non-occlusive coronary artery disease has almost a high risks of morbidity and
mortality as occlusive coronary artery disease.
This patient was transferred to the hospital and had an excellent outcome. Inferior wall
MI usually has a good prognosis as compared to most other MIs. Post treatment should
be aggressive to decrease the risk factors involved. Cardiac rehab whenever possible
should be started post MI.
Prevention of coronary artery disease should start early in life with most factors being
modifiable. Counseling early on about multiple risk factors should be addressed and
corrected. Heart disease is the number one cause of death in the United States and
prevention should be a major objective of physicians.
Reading: Rakel’s Textbook of Family Medicine pp 529 - 541