[The value of myocardial mass determination in the evaluation of left ventricular functional value in chronic mitral insufficiency. Apropos of 44 cases]. / Intérêt de la mesure de la masse myocardique dans l'évaluation de la valeur fonctionnelle du ventricule gauche de l'insuffisance mitrale chronique. A propos de 44 cas.

The functional value of the left ventricle in chronic mitral incompetence, determined as a function of haemodynamic and angiocardiographic indices, has now become a difficult factor to determine because of the multiplicity of indices which exist, and because of disagreement about the pathological values which are often a function of the valvular pathology in the particular case. Moreover, the importance of myocardial hypertrophy is rarely taken into account. The ratio systolic work/myocardial mass (WS/WM) which lies between no limits in the normal subject (0.81+/-0.03 gm.g-1) has allowed us to classify 44 patients with chronic mitral incompetence into three groups: groupe I (WS/V(M) greater than 0.87 gm.g-1), characterised by an increase in WS proportionally superior to that of V(M) (hyperfunctional); group II (0.87 gm.g-1 larger than or equal to WS/V(M) larger than or equal to 0.75 gm-1), characterised by a parallel increase of mass and WS (isofunctional); group III (WS/V(M) less than 0.75 gm.g-1) in which the increase in mass is proportionally greater than the variation in WS (hypofunctional). A comparison between the selectivity of this relationship and that of other indices, which contain large areas of overlap between the various groups of patients, lead us to hope for a prognostic index which will take account of the myocardial mass and of the pump action of the left ventricle.

Early changes in coronary flow physiology after balloon angioplasty or stenting: a 24-hour Doppler flow velocity study.

To evaluate early changes in myocardial microcirculation after balloon or stent coronary angioplasty, we studied 57 patients undergoing coronary angioplasty with a Doppler-tipped guidewire, with (n = 26) or without stenting. Postprocedural quantitative coronary angiography and coronary flow velocity were measured after 10 min and 24 hr. As compared to stenting, no stenting was associated with a higher postprocedural stenosis rate (21% +/- 13% vs. 12% +/- 10%; P < 0.05), smaller coronary velocity reserve (CVR; 2.2 +/- 0.4 vs. 2.5 +/- 0.7; P = 0.04), and smaller relative CVR (0.8 +/- 0.2 vs. 1.1 +/- 0.3; P = 0.001). At 24 hr, CVR and relative CVR in the unstented group increased to the level in the stented group, mainly because of a decrease in basal average peak velocity (APV). Overall, there was a significant negative linear relation between CVR and APV variations during the 24-hr period. In the subgroups with persistent abnormalities, CVR variation was closely related to the basal APV/reference APV ratio. In conclusion, coronary reserve normalization can occur within 24 hr after coronary angioplasty and is closely dependent on postangioplasty APV. Myocardial distal resistances should be considered when interpreting postangioplasty CVR.