Background: Dynamic cardiomyoplasty is a relatively new surgical procedure proposed for treatment of severe myocardial failure. Limited clinical experience suggests that this procedure reverses congestive heart failure, improving the long-term survival.
Methods and results: In this investigation, the late effects (16.5 +/- 4.8 months after surgery) of cardiomyoplasty on left ventricular mechanics and diastolic filling were studied in eight male patients (mean age, 45 +/- 7 years). The investigation was performed with the myostimulator on and off (24 +/- 1 hours off) using a microtip catheter to obtain the left ventricular pressures simultaneously with Doppler (inflow velocities) and M-mode and two-dimensional echocardiographic recordings. Statistical comparisons were made with Student's t test for paired data. Dynamic cardiomyoplasty increased the maximal elastance (17 +/- 1 versus 21 +/- 1 mm Hg/cm, P = .006) and decreased the systolic wall stress (253 +/- 17 versus 190 +/- 12 g/cm2, P = .029). Left ventricular end-diastolic pressure decreased (27.1 +/- 2.8 versus 17.6 +/- 1.7 mm Hg, P = .019), as did end-diastolic circumferential wall stress (69 +/- 8 versus 37 +/- 5 g/cm2, P = .002). The chamber and muscle stiffnesses decreased (120 +/- 31 versus 52 +/- 11 mm Hg/cm, P = .017; 994 +/- 185 versus 426 +/- 76 g/cm2, P = .002, respectively). The pattern of left ventricular diastolic filling changed, with a decrease of early peak flow (231 +/- 20 versus 217 +/- 21 mL/s, P = .022), of deceleration time (163 +/- 28 versus 116 +/- 26 seconds, P = .001), and of flow area during rapid filling (105 +/- 15 versus 75 +/- 12 mL, P = .004) and an increase of flow area during atrial contraction (39 +/- 4 versus 88 +/- 9 mL, P = .001).
Conclusions: Our detailed evaluation of left ventricular mechanics demonstrates that cardiomyoplasty has significant multiple beneficial effects on dilated myopathic heart.