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Background . Over the past several years, considerable experience has accumulated in performing coronary anastomoses on the beating heart, and various aspects of minimally invasive approaches have been simplified. In an attempt to further simplify and decrease the "invasiveness" of this procedure, performing this operation without endotracheal general anesthesia was deemed feasible in certain subsets of patients. Methods . Between October 1998 and June 1999, 5 patients underwent coronary artery bypass grafting without endotracheal general anesthesia, using high thoracic epidural block to construct extension grafts with a short segment of radial artery, between the in situ left or right internal thoracic arteries and the left anterior descending (n = 4) or right coronary arteries (n = 1). There were 2 female and 3 male patients, with a mean age of 67.4 ± 8.3 years. Results . The perioperative course of the patients was uneventful. There was no perioperative morbidity or mortality. No patient was converted to general anesthesia or to conventional operation. Control angiograms revealed patent anastomoses in all patients. In 1 patient, spasm of the radial artery graft was observed that was relieved 3 weeks later spontaneously. Mean length of hospital stay was 2.2 ± 0.4 days. All patients were symptom free and returned to normal daily life at the first postoperative month. Conclusions . Our initial experience confirms the feasibility of performing coronary bypass grafting in the conscious patient without endotracheal general anesthesia.

Background . A major concern in evaluating dynamic cardiomyoplasty has been whether the synchronous stimulation of latissimus dorsi muscle is essential for benefit or not. We studied 10 patients to determine the efficacy of the systolic augmentation generated by the synchronous electrical stimulation of the latissimus dorsi muscle. Methods . Left ventricular ejection fraction, end-systolic and end-diastolic volume indexes, and stroke volume index obtained during resting, peak exercise, and recovery periods ("on" values) were compared with those obtained 1 week after cessation of electrical stimulus ("off" values). Double product and estimated total body oxygen consumption at peak exercise were also calculated and compared. Results . Higher ejection fractions (0.36 ± 0.07 versus 0.33 ± 0.06 at rest, 0.40 ± 0.07 versus 0.33 ± 0.07 peak exercise, and 0.37 ± 0.06 versus 0.31 ± 0.06 at recovery) and lower end-systolic volume indexes with relatively constant end-diastolic volume indexes were observed with the cardiomyostimulator on. Further, exercise response was better with the cardiomyostimulator on. Double product indirectly reflected better myocardial oxygen supply/demand ratio when on at peak exercise (17 ± 2.2 mm Hg × beats/min × 10 −3 for on versus 19 ± 2.6 mm Hg × beats/min × 10 −3 for off). Estimated total body oxygen consumption was improved at peak exercise when the cardiomyostimulator was functional (12 ± 2.7 mL · kg −1 · min −1 versus 11 ± 2.6 mL · kg −1 · min −1 ). Conclusions . Current data suggest a true systolic assist during synchronous contractions of the latissimus dorsi muscle. It is thought, therefore, that synchronous electrical stimulation is essential for maximum benefit and all the beneficial effect of cardiomyoplasty certainly cannot be attributed to simple wrapping itself.

The hemodynamic effects of intraaortic balloon pumps (IABPs) are well known. The use of IABPs is prone to many complications, including those classified as vascular. These complications are said to be more frequent with percutaneous insertion techniques. These complications and the algorithm for identifying patients who are most likely to suffer vascular complications were evaluated in a retrospective manner in a group of patients that received percutaneous IABPs. The study group consisted of 449 patients. The mean age of these patients was 53.6 +/- 12.8 years (range, 18 to 80 years), and 24.7% were female. The early mortality rate of these patients was 53.2%. The mortality for patients in whom vascular complications developed was significantly higher than that in the patients who did not suffer any vascular complications (65.7% versus 50.8%; p = 0.018). Minor or major vascular complications developed in 17.4% (n = 78) of the patients. There was no statistical difference in the frequency of complications between the patients who received a sheathless IABP and those who received a sheathed IABP. Ischemic complications occurred in 16.6% of the patients who received a sheathless IABP and in 17.6% of the patients with sheathed IABPs (p < 0.05). Diabetic patients (relative risk, 2.5), female patients (relative risk, 1.83), patients with peripheral vascular disease (relative risk, 3.69), and patients undergoing coronary artery bypass operations (relative risk, 2.08) were at increased risk for suffering vascular complications. These risk factors should be evaluated before insertion of an IABP, and routes other than percutaneous femoral insertion are preferred if the patient is IABP dependent.

We report an unusual outcome of an ascending aorta aneurysm ruptured into the main pulmonary trunk. After successful emergency repair, an acute respiratory distress syndrome developed perioperatively and complicated the postoperative period. The patient could not be weaned from mechanical ventilation for a long time. The patient was discharged on the 62nd day of admission in good condition.

This report describes mitral valve replacement using a unique subxiphoid approach with a lower ministernotomy and a skin crease incision and compares the operative and echocardiographic results to patients undergoing mitral valve replacements using previously described strategies.Fifty-four patients underwent mitral valve replacement using a subxiphoid approach (group 1); 32 patients underwent mitral valve replacement, 11 patients underwent mitral valve replacement + tricuspid reconstruction, 2 patients underwent mitral valve replacement + tricuspid valve replacement, and 9 patients underwent mitral reconstruction. This group of patients was compared to 11 patients who underwent mitral valve replacement through a superior ministernotomy (group 2) and 29 patients who underwent mitral valve replacement with full median sternotomy (group 3, 22 mitral valve replacements, 2 mitral valve replacements + tricuspid reconstruction, 2 mitral reconstructions, and 3 mitral reconstructions + tricuspid reconstruction).There was no operative mortality in all groups. The operation lasted significantly longer in group 2 patients compared to group 1 and 3 patients (p0.01). Postoperative mediastinal drainage was significantly lower in groups 1 and 2 (p0.001). Pain assessment revealed no difference between the groups. Three patients in group 1 presented with pericardial effusion. Except for this complication, early postoperative echocardiographic findings of the patients were similar in all three groups. All patients were in New York Heart Association functional class I or II at the second postoperative month, irrespective of the surgical technique used.There was no prominent superiority of the ministernotomy approaches over the standard median sternotomy approach. However, the reliability of the subxiphoid approach is documented echocardiographically and any type of mitral replacement can be performed with this approach.

Background . Optimal synchronization delay (SD) for triggering the implanted cardiomyostimulators in patients undergoing latissimus dorsi dynamic cardiomyoplasty has not been clearly defined. Generally a synchronization delay time of 45 to 60 ms is used in the current practice, in which the implanted cardiomyostimulator stimulates the latissimus dorsi muscle 45 to 60 ms after mitral valve closure acquired with M-mode echocardiography. We investigated the effect of shortening or prolonging the delay time on cardiac functions. Methods . We studied 10 patients who were in their first 2 years postoperatively. Three values for SD (SD = 0 ms, 45 to 60 ms, and 150 to 160 ms) were echocardiographically evaluated for their influence on both systolic and diastolic left ventricular parameters. Results . Ejection fractions were 0.27 ± 0.07, 0.28 ± 0.07, and 0.32 ± 0.06; peak aortic velocities were 0.85 ± 0.8, 0.86 ± 0.11, and 0.92 ± 0.8 m/s; and velocity-time integrals were 0.16 ± 0.03, 0.16 ± 0.03, and 0.19 ± 0.03 m for the SD values of 0, 45 to 60 ms, and 150 to 160 ms, respectively. Diastolic parameters were also measured. Isovolumetric diastolic relaxation time was 97.5 ± 49, 97.20 ± 44, and 111.8 ± 49 ms; deceleration time was 83.67 ± 32, 88.48 ± 35, and 92.68 ± 34 ms; and ratio or velocity-time integral of e wave to velocity-time integral of a wave was 3.09 ± 0.98, 2.48 ± 0.69, and 2.38 ± 0.65 for the SD values of 0, 45 to 60 ms, and 150 to 160 ms, respectively. Systolic functions were better when SD was set at 150 to 160 ms, but there was a diastolic compromise. On the other hand, diastolic parameters were more favorable when SD=0 (ie, cardiomyostimulator triggered without delay) but the systolic assist was suboptimal. Systolic and diastolic parameters seemed relatively well-balanced with the current practice of setting the synchronization delay at 45 to 60 ms. Conclusions . The most favorable systolic effects were obtained with a prolonged delay of synchronization (150 to 160 ms), at some expense of diastolic functions. On the other hand, with a short or absent delay, diastolic parameters were improved but systolic parameters became suboptimal. Therefore, the current practice of setting the SD between 45 and 60 ms after echocardiographic mitral valve closure is suggested for the optimal timing for cardiomyostimulator stimulation in patients who have undergone latissimus dorsi dynamic cardiomyoplasty. Yet a great deal of individualization is necessary, and fixed preset values cannot definitely be determined because one setting does not fit all patients.

This study was performed to assess the functional capacity of the survivors of septal myectomy for the treatment of hypertrophic obstructive cardiomyopathy in long-term follow-up as assessed by dobutamine stress echocardiography.Sixty-nine patients with hypertrophic obstructive cardiomyopathy underwent septal myectomy between 1975 and 1996. The mean age was 25.4 +/- 13.6 years (range, 6-58 years), and 10 of the patients were women. The early mortality was 4.3%. Hospital survivors (95.7%) were followed up for a mean of 43.8 +/- 28.7 months (range, 6-114 months).The postoperative mean functional capacity of the group was 1.47 +/- 0.56. No late deaths were reported. Forty-nine patients (74.2%) were evaluated with standard echocardiographic techniques, and 29 (43.9%) patients underwent dobutamine stress echocardiography. There was a significant decrease in the thickness of the interventricular septum after surgery. The mean preoperative and postoperative septal thickness was 1.99 +/- 0.59 cm (range, 1.3-3.8 cm) and 1.55 +/- 0.41 cm (range, 0.96-2.8 cm), respectively (p0.004). The mean posterior wall thickness was significantly less than the preoperative value (p = 0.008) and the left ventricular end-diastolic diameter was slightly greater in the postoperative measurements, but the difference was not significant (p = 0.162). Postoperative left ventricular outflow systolic gradients were reduced significantly when compared with preoperative values (preoperative mean, 78.4 +/- 33.6 mm Hg, range, 50-212 mm Hg versus postoperative mean, 17.9 +/- 15.9 mm Hg: range, 0-40 mm Hg; p0.0001).Septal myectomy for patients with hypertrophic obstructive cardiomyopathy is a safe procedure with excellent clinical and functional results in the long-term follow-up.

Forty patients with coronary artery disease were included in this study. Half of them received cold crystalloid and cold blood cardioplegia (group 1) and half received normothermic blood Cardioplegia (group 2). In group 1, left ventricular stroke work index was 24 ± 3 g · m/m 2 1 hour after the operation, 29 ± 8 g · m/m 2 12 hours after the operation, and 33 ± 6 g · m/m 2 24 hours after the operation. In group 2, left ventricular stroke work index was 37 ± 4 g · m/m 2 1 hour after the operation, 37 ± 4 g · m/m 2 12 hours after the operation, and 44 ± 7 g · m/m 2 24 hours after the operation. Myocardial oxygen extraction 20 minutes after the termination of cardiopulmonary bypass was 0.28 ± 0.03 in group 1 and 0.44 ± 0.08 in group 2. Myocardial lactate extraction at the same time was −0.09 ± 0.02 in patients receiving cold blood cardioplegia and 0.17 ± 0.07 in patients receiving normothermic blood cardioplegia. Electron microscopic study revealed no calcium accumulation in the mitochondria in group 2 patients, whereas calcium accumulation was present in the other group.