Staged resection of bilateral pleuropulmonary blastoma in a two-month old girl.

Pleuropulmonary blastoma is a rare unilateral intrathoracic tumor of childhood. We report an unusual case of bilateral pleuropulmonary blastoma in a two-month old girl who underwent staged thoracotomies for complete wedge resection of both neoplasm. She remains well and tumor free two years after the operation.

Double closed loop obstruction and perforation in a previous Roux-en-Y gastric bypass.

A healthy 45-year-old woman with a previous Roux-en-Y gastric bypass presented with the signs, symptoms and blood analysis results consistent with acute pancreatitis. She was initially treated nonoperatively and subsequently went into circulatory shock. Computerized tomographic scan and exploratory laparotomy revealed a volvulus of the afferent jejunal limb with secondary obstruction, necrosis, and perforation of the bypassed stomach.

The effects of prosthetic cardiac binding and adynamic cardiomyoplasty in a model of dilated cardiomyopathy.

OBJECTIVE: Because adynamic cardiomyoplasty, or wrapping skeletal muscle around the heart, had been shown to provide a girdling effect and delay progressive ventricular dilatation in heart failure, a similar girdling effect by the much simpler procedure of cardiac binding, using a prosthetic membrane to wrap the heart, was studied and compared with that of adynamic cardiomyoplasty. METHODS: Twenty-one dogs were divided into control, adynamic cardiomyoplasty, and cardiac binding groups. Cardiac dimension and hemodynamic studies were carried out before and 4 weeks after rapid pacing at 250 beats/min. For adynamic cardiomyoplasty, the left latissimus dorsi muscle was used for the cardiac wrap; for cardiac binding, a Marlex sheet (C. R. Bard, Inc., Murray Hill, N.J.) was used. Serial two-dimensional echocardiography, right heart catheterization, and in the cardiac binding group, left heart catheterization were performed. RESULTS: Four weeks of rapid pacing induced severe heart failure and cardiac dilatation. The magnitude of ventricular dilatation at the end of rapid pacing was less in the cardiac binding group than in the control group and least in the adynamic cardiomyoplasty group. Left ventricular end-diastolic volume, end-systolic volume, and ejection fraction were 82.1 +/- 21.1 ml, 67.1 +/- 16.0 ml, and 17.5% +/- 5.8%, respectively, in the control group; 61.9. +/- 8.1 ml, 44.1 +/- 7.8 ml, and 30.1% +/- 3.6%, respectively, in the cardiac binding group; and 51.8 +/- 8.7 ml, 30.3 +/- 10.4 ml, and 27.0% +/- 4.0%, respectively, in the adynamic cardiomyoplasty group. CONCLUSIONS: Both adynamic cardiomyoplasty and cardiac binding reduced cardiac enlargement and functional deterioration after rapid pacing, with adynamic cardiomyoplasty appearing to be more effective, perhaps because of the adaptive capabilities of the skeletal muscle wrap. However, cardiac binding is a simpler and less invasive procedure, which may be useful as an adjunct to prevent or delay progressive ventricular dilatation in heart failure.

Mechanisms of cardiomyoplasty: comparative effects of adynamic versus dynamic cardiomyoplasty.

BACKGROUND: The apparent paradox seen in patients who have undergone dynamic cardiomyoplasty and shown substantial clinical and functional improvements with only modest hemodynamic changes may be due to inappropriate end points chosen for study, a result of incomplete understanding of mechanisms involved. The purpose of this study was to compare the relative role of the passive "girdling effect" and the dynamic "systolic squeezing effect" of the wrapped muscle in cardiomyoplasty. METHODS: The control group of 6 dogs underwent 4 weeks of rapid pacing (250 beats/min) to induce severe heart failure followed by 8 weeks of observation without rapid pacing. The trajectory of recovery in hemodynamics and cardiac dimensions was followed with echocardiography and Swan-Ganz catheters. In the "adynamic" cardiomyoplasty group (n=4), the left latissimus dorsi muscle was wrapped around the ventricles and allowed to stabilize and mature for 4 weeks. This was followed by rapid pacing and recovery as in the control group. In the "dynamic" cardiomyoplasty group (n=3), the same protocol for the adynamic group was followed except that a synchronizable cardiomyostimulator was attached to the thoracodorsal nerve of the muscle wrap. This allowed the latter to be transformed during the rapid-pacing phase and permitted dynamic squeezing of the muscle wrap to be generated by burst stimulation synchronized with cardiac contraction in a 1:2 ratio. RESULTS: Baseline data were comparable in all groups prior to rapid pacing. After 4 weeks of rapid pacing, the left ventricular ejection fraction was higher in the adynamic (27.0%+/-3.9%; p < 0.05) and dynamic (33.3%+/-2.3%; p < 0.02) cardiomyoplasty groups compared with controls (18.8%+/-8.3%). Similarly, ventricular dilatation in both systole and diastole was less in the adynamic (51.8+/-8.7 mL, [p < 0.002] and 38.2+/-7.2 mL [p < 0.001], respectively) and dynamic (62.0+/-7.2 [p < 0.02] and 41.3+/-3.5 mL [p < 0.005], respectively) cardiomyoplasty groups compared with controls. In the dynamic group, on and off studies were carried out after cessation of rapid pacing while the heart was still in severe failure, and they demonstrated a systolic squeezing effect in stimulated beats. Only this group recovered fully to baseline after 8 weeks. CONCLUSIONS: By reducing myocardial stress, both the passive girdling effect and the dynamic systolic squeezing effect have complementary roles in the mechanisms of dynamic cardiomyoplasty.

Pathologic findings of latissimus dorsi muscle graft in dynamic cardiomyoplasty: clinical implications.

BACKGROUND: We hypothesize that the integrity of the latissimus dorsi muscle graft used to wrap the heart may affect the clinical outcome of patients undergoing dynamic cardiomyoplasty. METHODS: By correlating the pathologic findings with their clinical course in five patients who died 1 month to 6 years after dynamic cardiomyoplasty operation, we sought to discern findings that might shed light on the pathophysiology of cardiomyoplasty. RESULTS: Of the two patients who had a limited clinical response, one had an atrophic, edematous latissimus dorsi muscle with fatty infiltration resulting from cardiac cachexia, and the other had insufficient length of latissimus dorsi muscle to cover a large heart. The remaining patients responded well clinically without signs of pump failure and died at various intervals, mostly of arrhythmias. Autopsy findings included the following: (1) one patient with ischemic cardiomyopathy as the underlying disease had development of rich vascularity in the interface between the muscle wrap and the epicardium; whereas in four others with idiopathic cardiomyopathy, such evidence of collateralization was far less evident. (2) There was a variation in the skeletal muscle transformation achieved, with the fraction type I fatigue-resistant fiber in the muscle wrap ranging from 60% to 100%, in spite of the identical transformation protocol used. Such variation is believed to be genetically based. (3) In one patient, the skeletal muscle was paced to contract at 30 to 50 times/minute (2:1 ratio) for more than 5 years. Nevertheless, the pathologic specimen of the muscle wrap showed only minimal interstitial fibrosis. (4) Relatively thin muscle wrap around the heart found at autopsy could be atrophy but most likely was related to muscle transformation, which is known to reduce muscle mass and increase capillary density. (5) All skeletal muscle grafts showed geometric conformation to the shape of the epicardium and grossly looked as if they were an additional layer of the ventricular wall. Such conformation may facilitate the modulation of the ventricular remodelling process in the failing heart, as has been described both in clinical and experimental studies. CONCLUSIONS: Our findings are consistent with and support a number of mechanisms proposed for cardiomyoplasty. Thus preservation of latissimus dorsi muscle graft integrity may be important in the success of dynamic cardiomyoplasty.