Role of Exercise Tolerance Test in the Screening of Suspected Myocardial Ischemia in Bangladeshi Patients

Abstract

Background: Ischemic Heart Disease (IHD) is preventable and reversible if early screening and elimination of the risk factors like life style modification and dietary intervention can be done. Exercise Tolerant Test (ETT) has become an important diagnostic tool to evaluate patient with suspected or known case of ischemic heart disease.
 Objective: To determine the frequency of IHD among subjects who presented with chest pain and to identify the common indications for ETT.
 Methodology: It was a cross-sectional study; the data was collected from ETT Unit of Mugda Medical College Hospital, Dhaka, Bangladesh using standard Bruce protocol.
 Result: Out of 200 patients, there were 124(61%) male and 78(39%) female who presented in the cardiology department for ETT. Common indications for ETT were evaluation of chest pain 180(90%), followed by general check-up 14(7%), post-PCI evaluations 4(2%) and post- CABG evaluation 2(1%).Presenting complaints were typical angina 12(6%), shortness of breath 56(28%), nonspecific chest pain 82(41%), chest compression 46(23%) and others 4(2%). Exercise ECG showed no ST changes in 138(69%) patients. The most common risk factors were hypertension, diabetes, smoking and obesity. Majority of the subjects 136(68%) were test negative whereas 42 (21%) were test positive and 22(11%) were test equivocal.
 Conclusions: It is concluded that most of the subjects presenting with the suspected symptoms of myocardial ischemia were negative for IHD, and so why we advocate the use of ETT as a screening tool in patients who presents with features simulating angina. This will prevent unnecessary hospital admission.
 Bangladesh Heart Journal 2019; 34(2) : 122-126

Gauging the Positive Predictive Value of Exercise Tolerance Test Using Angiographic Evaluation: A Cross-Sectional Analysis From a Developing Country

“…We evaluated the angiography results of 94 consecutive patients who were enrolled after they were labeled positive for inducible angina on ETT via the Bruce protocol. The literature regards ETT as an initial measure to assess and rule out myocardial ischemia [ 2 , 3 , 11 ]. The overall sensitivity of this inexpensive test is reported to be as high as 98%; however, its specificity is quite low [ 5 ].…”

“…The overall sensitivity of this inexpensive test is reported to be as high as 98%; however, its specificity is quite low [ 5 ]. Studies have reported that low specificity can be attributed to a myriad of contributing parameters including metabolic diseases, structural heart diseases, conduction disturbances, and digitalis therapy [ 3 , 5 ]. In developing countries, further evaluation in patients with coronary artery disease hinges upon the results of ETT, a relatively inexpensive and easy to interpret test [ 12 , 13 ].…”

“…Studies have reported that low specificity can be attributed to a myriad of contributing parameters including metabolic diseases, structural heart diseases, conduction disturbances, and digitalis therapy [ 3 , 5 ]. In developing countries, further evaluation in patients with coronary artery disease hinges upon the results of ETT, a relatively inexpensive and easy to interpret test [ 12 , 13 ]. Thus, patients with CAD cannot be ruled out without considering the probability and predictive value of the diagnostic test.…”

“…Thus, the PPV of males (78.9%) was found to be significantly greater than females (50%) with a significant p value of 0.01. A study done in Bangladesh concluded that the ETT was more sensitive for males, while the females were prone to have false-positive results in this regard [ 12 ]. Furthermore, another study reports that females have a greater risk of false-positive ETT, which has led to the use of more invasive radiological modalities (magnetic resonance imaging or radioactive scans) for initial evaluation of CAD [ 14 , 15 ].…”

“…Exercise tolerance test (ETT) is a frequently used investigation that utilizes a series of exercise tests and electrocardiography to evaluate ischemic cardiac pathologies [ 2 ]. ETT is the first-line investigation for CAD, which is used to decide which patient requires a referral to a cardiologist for further workup [ 3 ]. It has high sensitivity; however, it is less specific because various other cardiovascular and endocrinological diseases may influence its outcome [ 4 , 5 ].…”