Introduction .– Assessment of myocardial systolic and diastolic function is a primary objective in a perspective diagnosis, prognosis and therapy of ischemic heart disease. Based on the concept postulating that myocardial ischemia impairs diastolic function earlier than systolic function and since the atrial contraction is an integral part of diastolic function, it is legitimate to be interested in studying the atrial function in assessing diastolic function of ischemic cardiomyopathy.

Objective .– The aim of our work is to study in coronary patients the intake of conventional echocardiography and of pulsed doppler tissue imaging (DTI) in the evaluation of atrial contractile function.

Materials and methods .– Prospective study in 60 patients hospitalized for coronary heart disease that we compared to 40 witnesses. All the subjects have undergone a conventional echocardiography. Only the patients have a coronary angiography. We investigated the conventional echocardiographic parameters of the two atria namely lateromedian and supero-inferior diameters, atrial surfaces before and after atrial contraction, atrial volumes, fractional shortening (S-FE) and the fraction of ejection (V-FE) atrial. With pulsed DTI we measured peak velocity of atrial contraction (Va) at the free wall of the right atrium (Va-RA), the left atrium (Va-LA) and in the inter-atrial septum (Va-IAS). We studied the electromechanical delay of the onset, the peak and the end of atrial contraction by measuring respectively the time between the beginning of the P wave and the onset, the peak and the end of atrial contraction.

Results .– The mean age was 53.5 years ± 10.9 (26,76) comparable to the average age of witnesses. Ninety percent of the population was male. The conventional echocardiography study showed an increase in atrial dimensions associated to the reduction of fractional shortening (22.5 ± 12.1% vs. 32.7 ± 12.8%, P < 0.001) and ejection (35.8 ± 16.5% vs. 50.9 ± 11.9%, P < 0.001) of both atria in coronary patients compared with healthy subjects. Va was similar in the free wall of the RA and LA ( P = 0.1) and less on the IAS ( P < 0.001) respectively 14.9 ± 3.5 cm/s, 14.1 ± 3.8 cm/s and 10.9 ± 2.6 cm/s. In coronary patients, there are a significant decrease in the rate of atrial contraction in the three atrial sites (Va-LA: 11.5 ± 4 cm/s vs. 14.1 ± 3.8 cm/s; Va-RA: 12, 4 ± 3.7 cm/s vs. 14.9 ± 3.5 cm/s; Va-IAS: 8.8 ± 2.7 cm/s vs. 10.9 ± 2.6 cm/s, P < 0.001). Similarly, there’s a significant lengthening ( P < 0.001) in the electromechanical delay affecting the onset (RA: 67.3 ± 17.9 ms vs. 50 ± 11.9 ms; IAS: 73.1 ± 18.3 ms vs. 59, 3 ± 15.9 ms; LA: 81.3 ± 17.7 ms vs. 55.4 ± 13.1 ms), the peak (RA: 127.2 ± 110.3 ± 23ms vs. 27ms; IAS: 130.2 ± 18, 3ms vs. 120 ± 17.4 ms; LA: 138.1 ± 17.3 ms vs. 126.8 ± 17.4 ms) and the end (RA: 196.8 ± 25.7 ms vs. 175.6 ± 25.3 ms; IAS: 195 ± 22.2 ms vs. 179.6 ± 16.4 ms; LA: 195.5 ± 22.8 ms vs. 177.6 ± 23ms) of the atrial contraction. We found that the Va-LA: is independent of the presence or absence of a transwall myocardial infarction. The decrease of Va-LA below 10 cm/s is for a breach of the anterior interventricular coronary artery.

Conclusion .– The atrial contractile dysfunction on echocardiography can help to establish the positive diagnosis of myocardial ischemia and to assess its severity. Pulsed DTI can make a better understanding of the impact of coronary heart disease on the sequence of mechanical atrial contraction. New techniques (strain, 3D echo) could improve the contribution of the study of atrial function in ischemic heart disease.