There were 56 men and 34 women, or a sex-ratio of 1.64. The average age was 57.3 ± 10 years. The median age was 58 years.

Hypertension was the most frequent risk factor, with 31 patients accounting or 62% of cases. It was followed by dyslipidemia in 17 patients or 34% of cases and obesity in 16 patients or 32% of cases.

Symptomatology was not specified in 4 patients. Typical chest pain was noted in 45 patients (52.3%). Nineteen (19) patients or 22% had atypical pain.

The pre-test probability was intermediate (15% - 85%) in 77 patients (89.5%). It could not be calculated in the 4 patients for whom the symptom was not specified. TableA1 shows the general characteristics of the patients.

Rest electrocardiogram was normal in 70 patients or 77.8%.

Of the 20 patients with pathological ECG, 1 had an ST segment depression in 1 patient, 17 had sub-epicardial ischemia in a given territory, and 2 had episodes of ventricular extrasystole.

Echocardiography at rest was normal in most cases, with 86 patients or 95.6%. Other patients had segmental hypokinesia.

The duration of the exercise was recorded in 75 patients. The mean effort duration was 11.7 ± 5 min with extremes of 1 min and 26 min. It was less than 6 min in 27 patients or 36%. The mean maximum load reached was 12.9 ± 4.9 Mets.

Of the 34 women listed, two (02) had a maximum load of less than 5 Mets. In men, all 56 patients had a maximum load greater than 7 Mets.

The test was masked in 10 patients, or 11.1%. They had all reached 62% of their maximum predicted heart rate, so the test was considered maximal in them. Four of them had a positive test or 40%.

The test was maximum unmasked in 59 patients over 80. Of these 59 patients, 15 patients had a positive test on ECG (25%) and 6 on echography (10%).

The most common reason for stopping was muscle fatigue in 46.67% of cases, followed by maximum predicted heart rate impairment in 22.2% of cases and electrical disturbances in 20% of cases.

Finally, 26 tests (28.8%) were positive, 62 (69%) negative and 02 (2.2%) non-contributory.

Ten (10) of 26 electrical positive tests were associated with segmental kinetics wall disorders.

Eight of 26 tests were clinically positive with chest pain.

Among the electrical disturbances there were 19 ST segment depression. Elsewhere, 4 patients with ventricular rhythm disorders were considered positive.

A coronary angiography had been performed in 15 patients with positive tests either on clinical plan, electric or echographic.

In the 10 patients who had exercise kinetic wall disorders, 08 had coronary angiography. It was normal in 04 of them. The positive predictive value was then 50% in our study. TableA2 shows the repartition of patients admitted for ischemic test according to the results of coronary angiography.

In a patient whose exercise echography was negative with a high probability of coronary artery disease, the coronary angiography showed a two-vessel impairment with an intermediate lesion of Circonflexe and an intermediate lesion of right coronary vessel. This is a false negative. Sensitivity was then calculated at 80% in our study.

In the 15 patients with isolated electrical disorders, 06 had coronary angiography that was normal for each one of them.

We notice done incident of non-sustained ventricular tachycardia, in a 39 years old man with pre-test probability between 15% and 65%.

The examination noted a large segmental hypokinesis. Coronary angiography revealed a short, tight lesion in segment 1 of the left anterior descending artery.

Many studies have shown that the use of cardiac imaging has increased considerably in the past years [12] [13]. In the Western countries, this assertion was confirmed by several studies such as Carpegianni et al. [14], where the use rate of exercise echocardiography increased from 0% to 50% between 1983 and 2009. Our cohort of 100 patients over 34 months appears to be low given the increasing prevalence of coronary artery disease in our regions. But it has increased over the years.

In sub-Saharan Africa, no epidemiological data were found on exercise echocardiography [7] ; while it is known that non-invasive tests, especially exercise echocardiography can establish the probability of coronary artery disease with an acceptable degree of certainty [11]. This is even truer in our contexts where access to coronary angiography is limited. In this way, physicians should consider prescribing more exercise echocardiography, given its interest.

This is supported by the ESC 2019 recommendations which call for stress imaging, effort or pharmacological induced, as an initial option if local expertise and availability allow (I, B); Thus, we should see a decrease in diagnostic stress tests in favor of stress imaging if the clinical probability allows it.

In our study, we noticed a clear male predominance with 62.2% men and 37.8% women and a sex-ratio of 2.35. This male predominance is correlated with that observed in coronary artery disease, which varies between 65% and 80% in Africa [15].

Hypertension (62%) was the most common risk factor found in our population. This reflects the data found in the African literature with a prevalence of 59.7% according to the CORONAFRIC II study [2]. In the West, the same observation was made, Carpegianni [14] found a prevalence of hypertension estimated at 69% in 557 patients who had benefited from exercise echocardiography.

Exercise echocardiography finds all its great interest in hypertensive patients as hypertension is a disease that is widely under-diagnosed and under-treated, and sometimes revealed by ischemic heart disease [16].

Concerning symptoms, the majority or 51.6%, had consulted for a typical chest pain. We noticed a significant proportion of atypical pain (18.7%) and asymptomatic patients (14%). This should encourage a better assessment of pre-test probabilities that could limit inappropriate prescriptions.

The use of resources is optimal only if pre-test probability, based on clinical data, is taken into consideration before choosing non-invasive tests.

In our series, 8.1% of patients had a low pre-test probability and should not then benefit from a stress test according to ESC recommendations on stable angina [11]. The major part of patients, 61.6%, had a low intermediate probability between 15% and 65%, a simple exercise electrocardiographic could be justified in them; however, the recommendations prefer exercise echography if available. The indication of exercise echocardiography was formal in 27.9% of the patients that had a probability between 66% and 85%.

The remaining 2.3% had a pre-test probability over 85% and should then benefit from an invasive test.

Practitioners should then no longer base themselves on symptoms alone but rather on the pre-test probabilities proposed by the recommendations for the prescription of any diagnostic test.

In our study, the exercise test was masked in 11.1% of patients. Bouzas Mosquera [17], during its last study period, found 16.2% of patients with beta-blockers.

It has been proved that subjects suffering from angina and receiving beta blockers could achieve a higher exercise capacity without showing ischemic signs [18]. This is due to the fact that the use of a β-blocker decreases both the incremental and maximum heart rate obtained during the exercise, thus limiting the physiological interpretation of the cardiac response and thus the diagnostic accuracy [18]. This could explain the low positive predictive value around 50%. Patients should be better prepared by adjusting their medication, especially beta-blockers that must be stopped 48 hours before the exam.

But the sensitivity found in our work (80%) is similar to the values found in the literature which are in the range of 80% to 85% [19]. This confirms the diagnostic value of exercise echocardiography which has the advantage of being more available, cheaper and less harmful than other techniques using radioisotopes and which have a similar sensitivity.

In our study, only one minor incident was reported, the non-sustained ventricular tachycardia. There were no major complications (myocardial necrosis, death). The overall complication rate is estimated at 1.1%. Another benefit is its safety, with the largest record of exercise echography complications covering more than 45,000 studies [20].

There were no deceases, eight episodes of resuscitated ventricular fibrillation, five sustained ventricular tachycardias, 51 non-sustained ventricular tachycardias, one myocardial infarction, and 54 unstable coronary syndromes. This test can be considered particularly safe since the overall rate of non-fatal complications is 0.2%.

With a low complication rate, exercise echocardiography is a safe and comfortable exam.