Historically, the right heart was viewed as less important than the left heart in the maintenance of normal overall hemodynamic performance. However, there is now considerable evidence that emphasizes the significance of intact right ventricular (RV) function. The RV's anatomy and physiology are reviewed in order to provide insight into how changes in volume can be accommodated within a low-pressure environment and how this contributes to hemodynamic stability. The interdependent relationship between the right and left ventricles is also explored. The contribution of RV performance to overall hemodynamics is best exemplified when the RV becomes diseased. RV infarction, atrial septal defect, and cor pulmonale are used as examples to illustrate the dramatic sequelae associated with RV dysfunction, as well as to identify the RV's specific adaptive mechanisms.

Assessment of the distal pulmonary vasculature in patients with pulmonary hypertension has been limited to qualitative description of pulmonary arteriograms. Digital parametric imaging, using contrast density and transit time, has been used to qualitative blood volume and flow in the coronary and renal vascular beds. This study was performed to determine whether digital parametric imaging can quantitate vascular volume in the distal pulmonary capillary bed with pulmonary flow intact.

To assess the hemodynamic limitations of exercise in patients with mitral stenosis (MS), 29 patients with MS (mean age 49, mean valve area 1.4 cm2) and 29 age matched controls underwent symptom limited upright bicycle exercise with simultaneous expired gas analysis, right heart catheterization and radionuclide angiography. Supine rest hemodynamics and left ventricular volumes were abnormal in MS patients compared to control. Despite maximal (MAX) exercise effort, MS patients achieved a lower MAX heart rate (HR) and oxygen consumption (VO2/kg) compared to control. With exercise. other intergroup differences were accentuated, especially for MAX cardiac index (CI), pulmonary capillary wedge pressure (PCWP), and end-diastolic volume index (EDVI)

Acute and long-term efficacy of internal mammary artery (IMA) graft angioplasty has been limited to isolated ease reports and small patient series with limited angiographic follow-up. Over a 9-year period, 68 consecutive patients (74% male; median age: 61 yrs) underwent PTCA of IMA stenoses. In 59 patients, the lesion was located at the distal anastomosis, while in 9 patients, the lesion was located in the body of the graft. Median graft age was 9 months. The procedural success rate was 88%. The unsuccessful procedures were due to: inability to cross with wire/device due to excessive vessel tortuosity (5), major dissection (2), and inability to dilate (1). No patient experienced an in-hospital re-occlusion, distal embolization or CABG.

Background Although serotonin has been postulated as an etiologic agent in the development of carcinoid heart disease, no direct evidence for different ambient serotonin levels in cardiac and noncardiac patients has been reported to date. Methods and Results The present study reviews our experience with 604 patients in the Duke Carcinoid Database. Nineteen patients with proven carcinoid heart disease (by cardiac catheterization and/or echocardiogram) were compared with the remaining 585 noncardiac patients in the database with regard to circulating serotonin and its principal metabolite, 5-hydroxyindole acetic acid (5-HIAA). No significant demographic differences existed between the cardiac and noncardiac groups; however, typical carcinoid syndrome symptoms (ie, flushing and diarrhea) were almost threefold more common in the cardiac group ( P <.001). Compared with the noncardiac group, heart disease patients demonstrated strikingly higher ( P <.0001) mean serum serotonin (9750 versus 4350 pmol/mL), plasma serotonin (1130 versus 426 pmol/mL), platelet serotonin (6240 versus 2700 pmol/mg protein), and urine 5-HIAA (219 versus 55.3 mg/24 h) levels. The spectrum of heart disease among the 19 patients showed a strong right-sided valvular predominance, with tricuspid regurgitation being the most common valvular dysfunction (92% by cardiac catheterization; 100% by echocardiogram). Conclusions These data suggest that serotonin plays a major role in the pathogenesis of the cardiac plaque formation observed in carcinoid patients.

Relief of superior vena cava (SVC) syndrome due to non-neoplastic mediastinal disease presents a formidable challenge. Long-term patency of surgically created bypass grafts has been poor, and the morbidity associated with these procedures is substantial. We report a case of SVC syndrome, caused by fibrosing mediastinitis, treated with Palmaz balloon expandable intravascular stents. Intravascular stents are a promising alternative for relief of non-neoplastic SVC obstruction.

We aimed to assess the change in global and regional myocardial function before and after surgical revascularization and their added value when compared with conventional measures in children with anomalous left coronary artery from the pulmonary artery (ALCAPA).Advanced echocardiographic assessment was performed pre- and postoperatively in 22 children with ALCAPA (eight male; median surgery age, 0.4 years; interquartile range, 0.21-1.05) and 22 healthy controls. Measurements included global and segmental longitudinal, radial, and circumferential two-dimensional speckle-tracking strain and postsystolic index.Global strains were lower in preoperative patients than in controls (longitudinal: −9% vs −21%; P < .001; circumferential: −11% vs −21%; P < .001; radial: 18% vs 60%; P < .001) and improved postoperatively when compared with preoperative findings (longitudinal: −9% pre vs −16% post; P = .002, circumferential:−11% pre vs −17% post; P = .012, radial: 18% pre vs 53% post; P = .001). Preoperatively, patients with normal global systolic function on conventional echocardiography had significantly impaired global longitudinal and radial strain compared with healthy controls. Global mechanical dyssynchrony improved significantly postoperatively (longitudinal postsystolic index 43 pre vs 6 post, P < .001; circumferential 15 pre vs 2 post, P = .001; radial 48 pre vs 5 post, P = .003). Despite overall improvement in most segments, global longitudinal and circumferential and segmental peak strain in some of the segments supplied by the ALCAPA remained postoperatively abnormal.This study shows that myocardial deformation indices were a more sensitive measure of LV dysfunction in patients before and after ALCAPA repair than conventional echocardiographic measures. We believe, therefore, they should be added to routine preoperative and serial postoperative follow-up assessment.

the thymus and had infiltrated the S3 segment of the left lung and the pericardium. However, no effusion was seen. Small met-astatic nodules were also scattered on the surface of the myocar-dium, and only a partial resection was performed. The tumor was confirmed to be malignant thymoma of epithelial origin. His-tochemically, the tumor cells were positive for keratin stain, and staining was negative for carcinoembryonic antigen, a-fetopro-tein, and human chronionic gonadotropin. The patient received 4,000 rad with Cobalt 60, and this resulted in the relief of chest pain and diminution of the tumor. Prednisolone was stopped 2 months later. Although the patient refused further chemotherapy, he remained symptom-free for 5 years up to the present time, without any complications such as myasthenia gravis, erythroid hypoplasia, or hypogammaglobulinemia. DISCUSSION The frequency of malignant thymoma is reported to be up to two-thirds that of benign thymoma."2 Malignant thymoma is defined by invasive characteristics of the tumor to adjacent organs, and prognosis is more closely related to gross characteristics at operation than to histologic appearances. Some thymomas that were benign in their early periods can develop an invasive character in their late clinical courses.2'3 Local invasion might occur into the pleura, pericardium, and lung. Reports of malignant thy-moma, however, presenting with only pericarditis or tamponade are few,4'5 and cytologic study of pericardial fluid has rarely been positive.4 Empiric antituberculosis treatment has been given with corticosteroids in life-threatening cases of suspected tu-berculous pericarditis with good results.6 And large doses of corticosteroids that were used coincidentally for the pericarditis in the present case of malignant thymoma turned out to be lifesaving. Although the mechanism of action remains speculative, corticosteroids were reportedly effective in 11 of 13 thymoma cases.7 The treatment of malignant thymoma consists of radical extirpation followed by adjuvant or combination radiotherapy with or without chemotherapy.2'3'7 In the present case, myocardial infiltration made radical extir-pation of the tumor impossible. After relief of pericarditis with corticosteroids, radiotherapy was very effective for this thymoma. Although infrequent, malignant thymoma may present solely as pericarditis, and the potential effectiveness of corticosteroids for such pericarditis should be noted.