Effects of paclitaxel and carboplatine combination on mechanical myocardial and microvascular functions: A transthorasic doppler echocardiography and two dimensional strain imaging study

Paclitaxel and carboplatine are frequently used chemotherapy drugs in the treatment of gynecologic malignancies. Little is known about the effects of these drugs on left ventricular mechanical and coronary microvascular functions. Forty patients (mean age: 53,8 ± 10,9) with no coronary artery disease or diabetes mellitus were enrolled. We evaluated left ventricular mechanical function by strain imaging and coronary flow reserve before and after sixth months of chemothreapy by transthoracic echocardiography. Coronary flow velocity was measured in the mid to distal LAD from foreshortened apical 2-chamber view at baseline and after dipyridamole infusion (0,56mg/kg/4 minutes). Coronary flow reserve (CFR) was calculated as the ratio of hyperemic to baseline diastolic peak flow velocities. Reginal velocities, strain, strain rate measurements were obtained from the mitral annulus by using the Velocity Vector Imaging (VVI) software. Measurement from different mitral anular regions were averaged. Heart faliure symptoms were not detected in any of the patients. There was also no significant change in left ventricular ejection fraction and cardiac output. After chemothreapy no significant difference was obtained in CFR either (CFR: 2,19 ± 0,26 versus 2,10 ± 0,33, p=0,3). However mean longitudinal strain and stain rate were significantly impaired after chemotherapy (-17,5 ± 2,6 % versus -16,2 ± 2,5 %, p<0,02; and -1,05 ± 0,12 s-1 versus -0,96 ± 0,11 s-1, p=0,01, respectively). In contrast mean longitudinal velocity did not change significantly after chemotherapy (7,2 ± 1,3 cm/s versus 6,9 ± 1,1 cm/s, p=0,06). There seems to be no effect of paclitaxel and carboplatine combination on CFR. However our results point out that this chemotherapy combination can impair left ventricular mechanical functions. This subclinical impairment is better detected by 2D strain an strain rate imaging rather than velocity imaging.