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Background: Left ventricular partial ventriculectomy (LVPV), an unconventional operation to reverse some aspects of the cardiac remodeling, has been proposed for treatment of congestive heart failure., Methods and Results: Twenty-four patients (age 46+/-9 years) referred to heart transplantation underwent isolated LVPV or LVPV associated to valve annuloplasty. Patients were in New York Heart Association functional class IV (15) or III (9) due to idiopathic dilated cardiomyopathy. Functional class, left and right ventricular ejection fraction (radionuclide), left ventricular end-diastolic and end-systolic diameter, and fractional shortening (by echocardiography), and hemodynamic variables were determined. The mean follow-up was 474+/-174 days. Survival at 30, 180, and 365 days was 92+/-6%, 67+/-10%, and 63+/-10%, respectively. Nine patients died, and the cause was associated with arrhythmias in 4 patients. The left ventricular end-diastolic diameters before and at 23+/-14 days, 188+/-27, and 365+/-14.8 days of follow-up were 82.6+/-9.8, 68.9+/-7.8, 69.9+/-6.9, and 70+/-5.3 mm, respectively (P=0.0001). The left ventricular end-systolic diameters were 73.5+/-7.4, 55.9+/-7.5, 57.4+/-7.8, and 55+/-5.5 mm (P=.0001). Fractional shortenings were 13+/-3, 19+/-4, 18+/-5, and 22+/-2%, respectively (P=.0001). The left ventricular ejection fractions before and 18+/-14, 188+/-26, and 369+/-3.6 days after the surgery were 17.2+/-4.7, 24.5+/-8.3, 24.5+/-7.4, and 23.7+/-6.1%, respectively (P=.004). The right ventricular ejection fractions were 20.5+/-6.2, 27.9+/-8.4, 28.2+/-10.1, and 27.4+/-7.3% (P=0.02). Pressures were unchanged. There was improvement in cardiac index from 2.11+/-0.52 to 2.53+/-0.64 L/min (P=.0037). Norepinephrine blood levels reduced from 702+/-258 to 439+/-307 pg/mL (P=.001). Most surviving patients presented improvement in functional class. Sustained ventricular tachycardias were observed in 9 patients (38%)., Conclusions: The left ventricular partial ventriculectomy may improve the left and right ventricular function, functional class, and cardiac output. These initial results were associated to high prevalence of sustained ventricular tachycardia. The ventriculectomy introduces the concept that reduction of left ventricular chamber diameter may improve cardiac function in heart failure. Further progress is necessary to improve the results and evaluate its proper role in the management of heart failure.

Background: The effects of cardiomyoplasty on cardiopulmonary exercise test characteristics are not fully known., Methods and Results: We determined in 19 patients who underwent cardiomyoplasty for treatment of refractory heart failure (New York Heart Association [NYHA] functional class III) before (pre) and at 6-month follow-up (post) maximum oxygen consumption (peak VO2), NYHA functional class, and resting left ventricular ejection fraction (LVEF) (MUGA). We analyzed the results according to pre peak VO2 < or > 14 mL/kg per minute and the correlation between the changes in absolute values of LVEF and peak VO2. Pre- and post-peak VO2 values were 15.9 +/- 4.4 and 18.6 +/- 6.4 mL/kg per minute, respectively (P = .059). In the subgroup with pre-peak VO2 < 14 mL/kg per minute, the peak VO2 increased from 11.1 +/- 1.9 to 16.4 +/- 6.2 mL/kg per minute (P = .02). The subgroup with peak VO2 > 14 mL/kg per minute showed pre- and post-peak VO2 of 19.2 +/- 2.6 and of 20.1 +/- 7 mL/kg per minute, respectively (P = .06). The pre-total exercise time of the entire group increased from 688.4 +/- 222.1 to 833.7 +/- 241.6 seconds (P < .04). For the subgroup with preoperative peak VO2 < 14 mL/kg per minute, exercise time improved from 585 +/- 76.9 to 825 +/- 186.3 seconds (P < .01). In the subgroup with preoperative VO2 > 14 mL/kg per minute, the preexercise and postexercise time was 763.6 +/- 264.4 and 840 +/- 282 seconds, respectively (P = .4). Pre-LVEF increased from 20.6 +/- 3.3% to 24.2 +/- 7.8% at 6 months of follow-up (P = .02). At 6 months of follow-up, 9 patients were in NYHA functional class I and 10 were in class II. There was no correlation between LVEF values and absolute values of peak VO2 before (r = .123, P = .6) and after (r = .27, P = .2) cardiomyoplasty. A weak correlation was observed between the changes in absolute values of peak VO2 and LVEF from the preoperative to the postoperative period (r = .48, P = .048)., Conclusions: Cardiomyoplasty is a useful method for improving NYHA functional class and LVEF in patients with heart failure. Peak VO2 < 14 mL/kg per minute before cardiomyoplasty may be a selection criterion with which to determine improved exercise capacity after surgery. The effects of cardiomyoplasty on LVEF appear to be partially associated with maximum exercise capacity changes.

Background: Long-term clinical and hemodynamic benefits of dynamic cardiomyoplasty (DC) have been reported. However, no information is available about long-term morphological changes in the wrapped latissimus dorsi (LD) muscle in humans., Methods and Results: The LD muscle flap was evaluated by magnetic resonance imaging (MRI) in 13 patients submitted to dynamic cardiomyoplasty for treatment of severe dilated cardiomyopathy. Eight patients were studied 15 days after the surgery (group 1) and 5 patients were studied from 24 to 52 months after the surgical procedure at the time of the cardiomyostimulator replacement (group 2). In the interim, LD was stimulated with burst of 6 pulses (duration, 185 milliseconds; burst frequency, 30 Hz) synchronized to every cardiac contraction, with a maximum of 100 LD contractions per minute. Images were acquired on a GE Sigma 1.5-T system (echo time, 25 milliseconds; repetition time, R-R x 2; slice thickness, 8 mm). The thickness of the LD decreased from 19.6 +/- 7.3 mm for group 1 to 7.6 +/- 0.8 mm for group 2 (P < .01). In addition, the signal intensity of the LD was compared with that of thoracic skeletal muscle and was found to be significantly increased in group 2 (2.19 +/- 0.42) compared with group 1 (1.04 +/- 0.07, P < .001). The signal intensity for group 2 on the T1-weighted images was similar to that of subcutaneous fat in those images., Conclusions: Morphological changes in the wrapped LD muscle consistent with fatty degeneration occur after DC and can be detected by MRI. Further studies will be necessary to demonstrate the clinical significance of such LD muscle flap changes.

Background: The main causes of death in patients with severe cardiomyopathy are progressive heart failure and sudden death. The influence of cardiomyoplasty on the incidence of sudden death and arrhythmias in patients with cardiomyopathy remains unclear. The aim of this study was to investigate the occurrence of arrhythmias and sudden death after cardiomyoplasty., Methods and Results: We studied 32 patients (26 male, 6 female; mean age, 48 +/- 12 years) who submitted to cardiomyoplasty for treatment of heart failure in New York Heart Association (NYHA) class III (n = 24) or class IV (n = 8). The etiology was idiopathic dilated cardiomyopathy in 27 patients, ischemic heart disease in 3 patients, and Chagas' heart disease in 2 patients. Patients were routinely studied before and every 6 months after cardiomyoplasty by means of radioisotopic angiography and 24-hour Holter monitor recordings. There were no operative or immediate postoperative deaths. During the postoperative period, 5 patients presented with acute atrial fibrillation and 1 had an episode of sustained ventricular tachycardia. All episodes were successfully treated with intravenous antiarrhythmic drugs or cardioversion. During follow-up (from 2 to 66 months), 15 patients died from sudden death (n = 5) or progressive heart failure (n = 10). Survival rates at 1, 2, and 4 years were 79.9 +/- 7%, 62.5 +/- 9.7% and 35 +/- 12.1%, respectively. At 6-month follow-up, NYHA functional class improved from 3.2 +/- 0.4 to 1.7 +/- 0.6 (P = .001) and left ventricular ejection fraction increased from 19.8 +/- 3.3% to 24 +/- 8.2% (P = .004). The mean values per day of premature ventricular complexes (PVCs) and episodes of nonsustained ventricular tachycardia (NSVT) did not change statistically. The mean number of PVCs per 24 hours before and at 6, 12, 24, 36, and 48 months after surgery were 126 +/- 44, 96 +/- 33, 90 +/- 29, 81 +/- 35, 71 +/- 35, and 59 +/- 48. The mean number of episodes of NSVT per 24 hours before and at 6, 12, 24, 36, and 48 months after surgery were 3.3 +/- 1.3, 1.9 +/- 0.5, 1.3 +/- 0.5, 1 +/- 0.5, 1.5 +/- 1.1, and 0.6 +/- 0.5, respectively. With respect to analysis of the idiopathic dilated cardiomyopathy subgroup, there also were no significant differences in the incidences of pre- and postoperative arrhythmias., Conclusions: Despite NYHA functional class and left ventricular function improvements observed after cardiomyoplasty, the incidence of arrhythmias did not change, and sudden death was an important finding mainly in late follow-up. The problem of sudden death after cardiomyoplasty, the mechanism that produces it, and the means to prevent it remain critical areas for future research.

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.

Background: Dynamic cardiomyoplasty may provide functional and hemodynamic improvement in patients with heart failure. The purpose of this study was to investigate the effects of cardiomyoplasty on global ejection fraction, regional wall motion, and geometry of the left ventricle., Methods and Results: These parameters were determined in 10 patients submitted to cardiomyoplasty for treatment of refractory heart failure by left ventricular (LV) angiography. The studies were performed before and 16.5 +/- 4.8 months after cardiomyoplasty with the myostimulator turned on. They were repeated 24 +/- 1 hours with the myostimulator turned off in eight patients. LV ejection fractions were determined by the area-length method, and the centerline method was used for assessment of regional wall motion. LV geometry was studied by LV major-to-minor axis ratio and sphericity index. A LV ejection fraction improvement from 15 +/- 8% to 30.9 +/- 8.3% (p < 0.01) was demonstrated with the myostimulator turned on after cardiomyoplasty. The values with the myostimulator turned off were 23 +/- 13%, remaining higher than the values observed before surgery (p < 0.05). Regional wall motion analysis showed an improvement in all studied regions. Regarding the LV shape, the left ventricle became markedly more spheric in the diastole., Conclusions: Dynamic cardiomyoplasty may improve LV function in selected patients. The analysis of LV wall motion corroborated these results, and these changes were associated with modifications in the LV geometry.

Surgical support to the failing heart has been investigated in the treatment of severe myocardial failure. Dynamic cardiomyoplasty was indicated in 32 patients with dilated or chagasic cardiomyopathy who were in New York Heart Association (NYHA) class III or IV despite maximum medical therapy. Fifteen patients were operated on, and 17 refused the surgical treatment and were maintained by clinical means. With an average follow-up period of 12.3 months, actuarial survival rates for cardiomyoplasty patients were 86.6% at 6 months, 78.7% at 1 year, and 65.6% at 2 years of follow-up, whereas patients under medical therapy presented survival rates of 58.8%, 41.1%, and 27.4% at the same periods, respectively (p = 0.03). Furthermore, five of the 11 surviving patients of the cardiomyoplasty group are in NYHA class I, five in class II, and one in class III. At 6 months of cardiomyoplasty follow-up, rest radioisotopic left ventricular ejection fraction increased from 20.1 +/- 3.9% to 26.8 +/- 7.5% (p less than 0.01). Cardiopulmonary exercise testing showed that maximum oxygen consumption during treadmill testing improved from 14.7 +/- 3.9 to 18.3 +/- 3.9 ml/kg/min (p = 0.01). At 1 year of follow-up, these data remained essentially unchanged. In conclusion, dynamic cardiomyoplasty reverses congestive heart failure and improves the long-term survival of patients with severe cardiomyopathies.

Stimulated skeletal muscle grafts have been proposed as a means to reinforce ventricular wall in the treatment of severe myocardial failure. Latissimus dorsi cardiomyoplasty was performed in 11 patients with advanced heart failure due to cardiomyopathy who were in New York Heart Association (NYHA) class III or IV despite maximal medical therapy. There were no operative deaths. Eight patients were followed for a mean of 10.8 months. Two patients remain in muscle conditioning protocol. One patient died with latissimus dorsi ischemia and congestive heart failure. Four of the eight patients in long-term follow-up are in NYHA class I, three in class II, and one in class III. At 3 months of follow-up, rest radioisotopic left ventricular ejection fraction increased from 20.5 +/- 3.6% to 26.8 +/- 8.1% (p less than 0.01). Doppler-echocardiography demonstrated that left ventricular segmental wall shortening improved from 11.3 +/- 2.5% to 16.5 +/- 3.9% (p less than 0.01) and left ventricular stroke volume from 22.9 +/- 4.6 to 33.1 +/- 10 ml (p less than 0.01). Cardiopulmonary exercise test showed that maximal oxygen consumption during treadmill test increased from 14.8 +/- 3.7 to 18.2 +/- 3.3 ml/kg.min (p less than 0.05). At 6 months of follow-up, all the above values remained essentially unchanged. Furthermore, nonsustained ventricular tachycardia was abolished without specific medical therapy in four patients. Thus, cardiomyoplasty improves left ventricular function, reverses congestive heart failure, and may improve long-term survival in severe cardiomyopathies.

Skeletal muscle grafts can be used to mechanically assist the failing heart. In 13 mongrel dogs, latissimus dorsi muscle was preconditioned in situ for 6-8 weeks. Biopsy samples of the muscles were obtained for histochemical analysis. In seven dogs, muscle force and fatigue were compared in conditioned and contralateral unconditioned (controls) muscles. In six dogs, latissimus dorsi cardiomyoplasty was performed in propranolol-induced acute heart failure, and its effects were evaluated by hemodynamic and echocardiographic parameters. Muscle conditioning was responsible for latissimus dorsi transformation to a muscle with predominantly fatigue-resistant type I fibers. Conditioned muscles developed less initial force (-27 +/- 6%) and a longer contraction time (+32 +/- 4%) (p less than 0.05) but did not show fatigue for less than 15 minutes. With synchronous pulse-train stimulation of the muscle flap, cardiac output increased from 1.4 +/- 0.1 (mean +/- SD) to 2.0 +/- 0.2 l/min (p less than 0.05), pulmonary wedge pressure decreased from 16.3 +/- 0.9 to 12.1 +/- 1.4 mm Hg (p less than 0.05), and left ventricular end-diastolic pressure decreased from 18 +/- 2.0 to 13.5 +/- 1.4 mm Hg (p less than 0.05). Echocardiographically derived ejection fraction increased from 39.3 +/- 2.4% to 59.6 +/- 2.9% (p less than 0.05), and fractional shortening increased from 15.4 +/- 1.1% to 26.3 +/- 1.7% (p less than 0.05). Thus, chronic stimulation of skeletal muscles induces fiber transformation and increases resistance to fatigue and force development. Cardiomyoplasty, on the other hand, improves ventricular function in the presence of acute heart failure. This surgical technique represents an alternative method of treatment for advanced myocardial failure.