[Cardiocirculatory adaptations during the initial phases of pregnancy. An echo-Doppler assessment]

During pregnancy the cardiovascular apparatus meets an important process of morphofunctional adjustment. However the very moment when this happens is not very well known. We observed thirty patients during the various GIFT phases (Gamete Intrafallopian Transfer) that consists in the intratubal transfer of male and female gametes and that represents also an ideal model for the study of pregnancy in the early phases. With echo-Doppler technique morphological and functional parameters of the left ventricle have been evaluated and at the same time estradiol and progesterone blood variations have been determined. In all the thirty patients to the increase of E2 corresponds a significative increment of telediastolic (Dd) and telesystolic (Ds) diameter and of systolic index (SI) and cardiac index (CI). At the same time a significant reduction of mean arterial pressure and of the index of a systemic vascular resistance has been observed. These data say that the systolic flow increment is not due to an increase of the ejection fraction but to an increase of the diastolic filling. The utilised mechanism has nothing to do with inotropism but to the preload reserve according Starling principle. The increase of the systolic output is the almost unique cause of the cardiac capacity increment because there is only a light increase of heart rate. Those patients in which GIFT gave a positive results, these variations are sustained while in the group of those patients not pregnant one can see a rapid return to basic values of the various parameters (except the presence of a significative Dd increment) together with the reduction of plasmatic E2. In conclusion our work results say that significative cardiovascular adjustments are evident from the earliest pregnancy phases and that these changes one can related to E2 plasmatic variations.