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Vous êtes ici : UFR Simone Veil - santéFRFormation continueAcute Cor Pulmonale05. Effects of acute cor pulmonale on the left ventricle

05. Effects of acute cor pulmonale on the left ventricle

Udden right ventricular dilatation within in an inextensible pericardium results in left ventricular compression, which is easily seen on echocardiographic examination (Figures 2, 5, 6, 7 et 10). Acute cor pulmonale therefore reduces left ventricular diastolic dimensions  (tables 2 et 3) (8, 9, 10). In massive pulmonary embolism, this sudden drop in preload causes acute circulatory insufficiency. In ARDS, the decrease in left ventricular preload is usually more progressive, but may also contribute to circulatory insufficiency.
Film 7 : Transthoracic apical four-chamber view in a female patient hospitalized following massive PE. Echocardiography reveals severe ACP. In particular, the RV is considerably dilated and so crushes the LV. Note also the relative hyperkinesia of the apical portion of the free wall of the RV, described in this setting by Goldhaber. It is simply the result of the marked dilatation of the RV.
Film 12 : In the same female patient as in films 10 and 11, TEE on D9 shows that right ventricular dilatation severely constrains the LV, which has a “glove finger” shape. The circulatory status now requires the infusion of 3 mg norepinephrine/hour. This trend follows marked alteration of the respiratory mechanics, due to a fibroproliferative phase. After a few days of corticosteroid therapy, ACP disappeared (see film 30) and the patient was cured.

Left ventricular compression by right ventricular dilatation contributes more to the reduction in LV diastolic filling if it occurs when the pulmonary circulation is partly obstructed: proximal obstruction by a thrombus in massive PE, distal obstruction by the action of high alveolar pressure on pulmonary capillaries in ARDS managed by assisted ventilation (11).

In addition to the reduction in left ventricular diastolic dimensions, Doppler echocardiography reveals abnormal relaxation which is seen in predominance of the A-wave over mitral flow (table 2 et 3). (Figure 4).
Film 13 : In the female patient of films 10, 11 and 12, TEE at D2 provided no evidence indicative of abnormal left ventricular relaxation: pulsed Doppler at the mitral annulus is normal, with a mitral E/A ratio greater than 1. 
E-wave: proto-diastolic filling wave. A-wave: end-diastolic filling wave (atrial systole).
Film 14 : In this female patient, onset of severe ACP at D9 was accompanied by abnormal left ventricular relaxation, with a mitral E/A ratio equal to or less than 1.




Table 3