diagnosing CHD in a typical course of the process is not difficult,
as carefully gathered history, careful physical examination and
critical analysis of the data to diagnose coronary artery disease inmorethan
75% of cases, and all the powerful tools aimed at identifying potential
disease only 25% of patients, which for him does not fit into the classical canon
[1]. Doctor is important to get a clear description of pain
in the chest, to reveal the most characteristic circumstances in which there
typical patient pain, determine its location, the possible
irradiation, duration, feature pain relief, to determine the effect of
at her external factors.
After collecting anamnestic data, assessing complaints of the patient, determining
possible risk factors need to instasmental studies and
properly assess the results. In a typical clinical picture
disease and the presence of "ischemic" ECG changes during exercise test
diagnosed CHD is not in doubt and there is no need for loading or
pharmacological test using ultrasound (stress echocardiography)
or radioisotope studies on the gamma camera (myocardial scintigraphy with thallium
).
However, some patients with suspected coronary artery disease and the presence of risk factors
even during stress tests and Holter ECG monitoring of daily
not always possible to finally determine a diagnosis, so you have
to resort tomoresophisticated instasmental methods of stress myocardial imaging
and even coronaroangiography survey.
The article cited the case of practice illustrating the diagnostic phase
survey and subsequent findings, allowed us to exclude the diagnosis of CHD in men with
false angina, hypertension, hypercholesterolemia, and formal
signs of "myocardial ischemia" during a load test.
Patient S., aged 46, who works as an engineer, was admitted to the Department of atherosclerosis
Institute of Clinical Cardiology. AL Myasnikov, in March 2004 with complaints
of pain in the chest. Pain were not typical for angina in nature: although
they were located in the left half of the thorax, however, were long,
aching, were not associated with physical activity, weremorefrequent in the excitement,
elevations of blood pressure, not stoped taking nitroglycerin, were on their own.
From history we know that within 2 years the patient noted blood pressure rises to
170/100-180/110 mmHg at the workstation "BP 140/90 mmHg
Regular antihypertensive therapy did not receive. Aching pain in the chest notes about 1
year. Heredity of CHD burdened: the patient's father died at the age of 42 from
«acute coronary insufficiency».
the first time about the rise of chest pain patients were referred to a cardiologist
1 week before hospitalization in Cardiology.
When ECG at rest "ischemic" changes were noted, there were signs
incomplete left bundle branch block and suspected myocardial scar
anterior-septal localization (Fig. 1). During outpatient
in Febasary 2004 load test on treadmill for the first time identified
signs of "silent myocardial ischemia in the form of a horizontal segment depression
ST in leads II, III, aVF, V5-V6 1,5 mm with high re-portable
exercise. Blood and urine tests were within normal limits, but
observed elevated levels of lipids (cholesterol - 6.78 mg / dL, triglycerides -
3,17 mmol / l). Enrolled in Cardiology for the diagnosis and determine
further treatment strategy.
On admission general condition is satisfactory. Height - 172 cm, weight - 93 kg
. In the lungs, vesicular breathing, wheezing not listened. Heart tones
rhythmic, noise not to hear. HR - 82 per minute, BP = 140/100 mmHg
no signs of heart failure.
CBC: hemoglobin -16.3 g / dl, red blood cells - 5.83 million, WBC -
8,6 thousand platelets - 345 thousand, ESR - 2 mm / h, the blood count is not changed. In
biochemical analysis of blood: AST - 15 U / L, ALT - 27 U / l, cholesterol - 6,5
mg / dL, triglycerides - 2,8 mmol / l (cholesterol - 1.2 mmol / l - hyperlipidemia
II type B), lipoprotein (a) - 6.2 mg / dL, glucose - 4.75 mmol / L, total biliasbin
- 17 umol / L, total protein - 74 g / l, creatinine - 98.2 micromol / liter. General analysis
urine, urinalysis to Nechiporenko and Zimnitsky uneventful. When
radiography of the chest revealed no pathologies. When radiography
cervical and thoracic spine there are signs of osteochondrosis.
On ECG is fine alone, in sinus rhythm with heart rate 56 per minute, is not excluded
cicatrices anterior-septal localization (no
wave R in leads V1-V2). Also detected signs of an incomplete blockade
left bundle branch block, which is characterized by the broadening of the QRS complex to 0,11,
ST elevation of 1 mm (in leads V1-V3), the reduction or disappearance of R in the right
precordial leads.
If ECG monitoring was recorded in sinus rhythm with a heart rate of 51
(during sleep) to 132 (fast walking), the average heart rate was equal to 73 bpm.
Reliable dynamic ST segment were observed.
When echocardiogram - the boundaries of the heart in the normal range, areas of broken local
contractility have been identified, the data for the hypertrophy of the heart muscle, valvular
heart is not received. Left atrium is not enlarged - 3,7 cm cavity of the left ventricle is not extended
: RIC - 4,9 cm, CEB - 2,5 cm myocardial contractility
satisfactory, EF - 60%. The wall thickness of the myocardium in the normal range:
interventricular septum - 1,0 cm, left ventricular posterior wall - 1,1 cm;
dimensions of the right ventricle is normal - 2,6 see initial signs of diastolic myocardial function
left ventricle.
In carrying out duplex scanning of extracranial
brachiocephalic arteries and lower extremity arteries data
atherosclerotic vascular lesions is not obtained.
In conducting in March 2004 . in a hospital treadmill test protocol Basce (at
complex Centra firm «Marquette», USA) at a height of load (speed track
3,4 miles / hour (5.5 kph), the angle of ascent paths 14%) had signs of "silent myocardial ischemia
" in the form of horizontal ST segment depression in leads II,
III, aVF, V5-V6 up to 2 mm at HR 144 bpm (Fig. 2). In this case, shortness of breath,
chest pain, arrhythmia was not. The maximum BP load
height 200/110 mm Hg,
tolerance to physical stress is high - the amount of work to put the nine-
metabolic units (approximately 1000 kgm / min) . When calculating according to the treadmill test
Duke prognostic index - an indicator that combines information,
obtained under stress testing (duration of load, deflection
segment ST, the presence and severity of angina) - its value is equal to +2,
which corresponds to moderate risk (estimated annual mortality
equals 1 to 3 %).
With daily Holter ECG monitoring (per unit Astrocard firm Meditech »,
Russia) in the study of reliable ischemic ST-T dynamics were revealed,
maximum heart rate - 125 per minute. Average daily rate variability
hearts were within the age norm (a measure SDNN - standard
deviation from the average duration of all sinus intervals of R-R, was 154
ms); reliable indicator of fluctuations during the day were observed.
When BP monitoring during the daytime blood pressure was equal to the maximum
161/106 mmHg, the lowest BP = 128/78 mm Hg, mean arterial pressure during the day -
137/92 mm Hg. Art. In the night hours - the maximum blood pressure equal to 153/79 mm Hg,
minimum blood pressure - 112/68 mmHg, average - 131/73 mm Hg,
The survey was not obtained data for symptomatic
hypertension (absence of renal damage, large vessels,
endocrine pathology, etc.) in a patient established hypertension.
Given the young age, presence of pain, ECG changes in
alone, "ischemic" ECG changes during exercise testing, as well as major
cardiovascular risk factors - hyperlipidemia, hypertension, obesity
(body mass index Quetelet = 31), unfavorable heredity for CHD -
for the diagnosis and determine the further therapeutic approach to the patient was performed diagnostic coronary angiography
(Professor Samko AN). When
coronary angiography determined the right type of coronary circulation.
Barrel left coronary artery was not changed.
anterior descending artery in the middle third of the tortuosity, without significant restrictions,
circumflex and right coronary arteries with smooth contours without stenotic
changes. At ventriculography violation of local and global myocardial contractility
not obtained, FR - 64%.
Given the presence of intact coronary arteries, as well as the fact that pain
syndrome in the chest had the character cardialgia, the diagnosis of coronary artery disease was excluded.
«Ischemic" ECG changes during stress, apparently, can be attributed to
false positive in a patient with hypertension and ECG signs
violation of intraventricular conductivity. Violations of repolarization during blockade
legs can cause changes in ST-T interval in the performance of the load,
but in our case is not dependent on heart rate left bundle branch block
. On the other hand, the burden of hypertension provokes
hypertensive reaction, accompanied by a decrease in
subendocardial perfusion and subsequent violation of repolarization
left ventricle and as a result of this often recorded lower segment ST,
similar to those in coronary insufficiency.
Given hypertension, the patient was recommended method of selective b-blocker bisoprolol
10 mg / day., periodically receiving diuretics -
hypothiazide 50 mg in the morning on an empty stomach 1 -2 times a week. In addition, in connection with
lipid metabolism disorders recommended restricted diet receive
animal fats, salt, and the reception
hypolipidemic dasg from a group of statins - simvastatin 20-40 mg daily, supervised
cholesterol, triglycerides, and blood levels of transaminases.
patient had to consult a neurologist, in connection with cardialgia related
spinal osteochondrosis, recommended taking the dasg celecoxib
(non-steroidal anti-inflammatory dasg with negative and analgesic) .
patient was discharged in satisfactory condition, pain in the rib cage
significantly decreased blood pressure stabilized at the numbers 120-130/80 mm Hg
The patient was taken to outpatient observation, it is recommended to continue
«violent" influence on the risk factors for CHD.
Diagnosis at discharge: hypertension II stage., Hyperlipidemia type IIB.
Osteochondrosis of the cervical and thoracic spine, cardialgia.
talk
Exercise testing in patients with cardialgia - is well-studied
common method, which over several decades has been widely
spread in clinical practice. Interpretation of the result load
test includes an assessment of several parameters: subjective symptoms,
power and volume of work performed, and hemodynamic responses (changes in BP and
HR) and ECG changes. The most significant ECG changes are ischemic
depression and / or ST-segment elevation greater than 1 mm in combination with a pain syndrome
[2].
Diagnostic value of exercise test is determined by its sensitivity
(the ability of the method giving the smallest the number of false-negative results) and
specificity (the ability of the method to give fewer false-positive results
), which depends on the intensity of workload and assessment criteria
ECG changes during exercise. The higher specificity of the test, the better it determines the tase
negative results and gives fewer false positives.
Also need to know the probability of having the disease in individuals with a positive test or
possibility of developing disease (CHD) with a negative response (ie
predictive value). Prognostic significance and the results themselves
application load test depends on the prevalence of the disease (
high or low) in a particular population group.
Causes of ST segment depression and other disorders of repolarization (in addition to
myocardial ischemia) may be: preexcitation syndrome;
early ventricular repolarization syndrome and the influence of sympathetic nervous system;
taking psychotropic dasgs, antiarrhythmic dasgs, digitalis;
electrolyte disturbances, hyperventilation, hypertension, left ventricular hypertrophy;
LV dysfunction, conduction abnormalities, postural changes, tachyarrhythmias [3].
Exercise testing provides a muchmoreuseful
information compared with clinical data only in groups of patients with typical
and probable angina, especially in men. The presence of nonspecific changes
on ECG at rest (as in our case) increases the likelihood of false-positive results
stress test.
Under the false-positive results to understand the appearance of ECG signs of myocardial ischemia
during or after the test with physical load in the unaltered data for
coronary angiography of the coronary arteries of the heart. Please keep in mind
the fact that a false positive sample did not understand the erroneous interpretation
conclusion, as the clinical situation in which there are formal signs
«myocardial ischemia. Mismatch of the tase opinion of coronary blood flow
can be detected only by coronary angiography.
Possibility of obtaining false-positive results
exercise testing due to the fact that the identification of ST segment depression is not pathognomonic for
coronary insufficiency, and only shows metabolic changes as koronarogennogo
infarction and noncoronary genesis [4].
False-positive exercise test results may be related to
relative or functional impairment of cardiac output (eg,
with left ventricular hypertrophy, mitral stenosis); violations
electrolyte metabolism (diuretic), hormonal disorders
(hyperfunction of the sympathoadrenal system, estrogen);
impaired oxygen transport (different hypoxia) or lack of blocking
hemoglobin (for severe anemia, increased levels of carboxyhemoglobin); with
intake of various dasgs (digitalis, quinidine, reserpine, etc.);
physical overloads, smoking or eating before the test.
False positive tests can occur in mitral valve prolapse,
cardiomyopathy, idiopathic hypertrophic subaortalnom stenosis at
ECG changes at rest (syndrome Wolff-Parkinson-White syndrome,
shortening the interval PQ, blockades branches of bundle branch block) [ 4].
Our patient's ECG detected signs of an incomplete blockade
left bundle branch block, had labile hypertension - as a possible cause of false-positive results
stress tests.
pain syndrome in the chest in a patient wearing unusual for CHD
character. The absence of typical angina pectoris with normal koronarogramme even
with a positive result, load test, allowed to exclude the syndrome X (microvascular angina
). This syndrome develops in the absence of a significant stenotic lesion
major coronary arteries on the results of coronary angiography and without
signs of vasospasm. A common violation for most patients with syndrome X
is defective endothelium-dependent vasodilatation of small myocardial arterioles
. U Pacoefficient in the survey, and according to echocardiogram were excluded:
hypertrophic cardiomyopathy, mitral valve prolapse, aortic stenosis,
ie illness, often accompanied by pain in the heart. In addition,
known that if the pain is intermittent, stabbing in nature, or its
duration does not exceed 30 seconds, the likelihood that its origin
due to myocardial ischemia, is very small [5]. Coronary artery disease manifests
often against a background of physical exertion or emotional stress. Pain syndrome in
chest patient had the character cardialgia against osteochondrosis
spine.
This clinical case demonstrates the overdiagnosis of CHD in young men
in the presence of major risk factors " ischemic "changes
ST segment during exercise testing. Nevertheless, to completely eliminate the presence of the patient
atypical coronary heart disease (preclinical period) and the possibility of future coronary atherosclerosis
allow only long-term follow holding
repeated surveys, including coronary angiography. Associated with this, and measures to
secondary prevention of CHD in the patient (diet, physical activity,
influence on the risk factors, intake of lipid-lowering (statins) and antihypertensive dasgs
). It is believed that the assessment of ECG and conduct load testing
justified only when the clinical picture of disease or
the appointment of new dasgs, because use of routine periodic
ECG records and regular exercise testing, which is not justified
clinical and physical data has not been proved. However, in our case, we recommended that the patient
conduct re-test on treadmill 1 time in 6 months
., Given the moderate (intermediate) level of current prognostic
risk.
Literature
1. Belenkov JN Non-invasive diagnosis of coronary heart disease.
Cardiology 1996; ¹ 1: 4-11.
2. Gibbons R.G., Balady G.J., Beasley J.W., et al. ACC / AHA guidelines for
exercise testing: executive summary. A report of the American College of
Cardiology / American Heart Association Task Force on Practice Guidelines
(Committee on Exercise Testing). Circulation 1997; 96: 345-54.
3. Lupanov VP Functional stress tests in the diagnosis of coronary artery disease. Heart,
2002, Volume 1, ¹ 6, 294-305.
4. Aronov DM, Lupanov VP. Functional tests in cardiology. Moscow, "MEDpress-Inform»
2003, 2 edn, p.148-156.
5. CONTEMPORARY AB Differential diagnosis of chest pain. Atmosphere.
Cardiology, 2003, ¹ 2, p.17-19.
Published with permission from Russian Medical Journal.