Cardiovascular diseases最新文献

Intraaortic balloon pumping (IABP) is an established therapeutic adjunct in the treatment of postcardiotomy/infarction low cardiac output states. Although the common femoral or iliac arteries are the preferred sites for balloon insertion, severe arterial occlusive disease may preclude entry by these methods. To circumvent this problem, alternative methods of insertion utilizing transthoracic approaches have evolved. In our institution, direct (transaortic) IABP insertion, combined with delayed sternal closure to avoid cardiac compression and possible tamponade, was performed in 28 adult postcardiotomy patients (mean age 60.4 +/- 3 years). The severity of generalized atherosclerosis was reflected in an overall survival rate of 28.6%. Retrospective analyses of the clinical courses of these patients revealed that the transaortic approach allowed utilization of larger and more effective balloons. Successful insertion of 30 and 40 ml balloons was accomplished in 27 of 28 (96%) of these patients, and one patient with a hypoplastic aorta required a 20 ml balloon. There were no complications directly attributable to this alternative site of balloon insertion, and tamponade was avoided. Delayed sternal closure was accomplished within 48 to 96 hours. We concluded that when severe peripheral vascular occlusive disease prevents insertion of intraaortic balloons via the femoral or iliac arteries in patients with low cardiac output, the alternative transaortic approach is indicated. Combined with delayed sternal closure in patients with postcardiotomy dilatation, additional benefits accrue.

A case of successful autotransplantation of the omentum is presented, and some of the possible uses of this technique are discussed. The procedure appears to be a sensible means of limb salvage in patients with Buerger's disease, an advanced state of vascular insufficiency, with a lack of run-off vessels.

This case report and 19-year follow-up concerns a patient with aortic insufficiency who was one of the first to undergo surgical treatment with a descending aortic valvular homograft. The historical perspective afforded here may stimulate ideas concerning advances in future methods and materials to be used in cardiac surgery.

This study characterizes left ventricular performance early after aortic valve replacement for severe isolated aortic regurgitation. Gated radionuclide ventriculography studies in 13 patients showed that left ventricular end-diastolic volume was reduced after surgery and that ejection fraction dropped significantly. Despite the fall in ejection fraction, the postoperative cardiac index was significantly greater than the preoperative value. Radionuclide ventriculography is a useful and reliable means of noninvasively assessing left ventricular function soon after aortic valve replacement for aortic regurgitation.

Dissatisfaction with the hemodynamic characteristics of available porcine valves prompted a clinical trial of the Ionescu-Shiley percardial xenograft (ISPX) valve. Three hundred fifty-six ISPX valves were implanted consecutively in 326 patients. Operative mortality was 2.6% (2/75) for aortic valve replacement alone and 7.7% (12/155) for aortic valve replacements that included reoperations and combined procedures such as mitral commissurotomy, annuloplasty, and coronary artery bypass. Operative mortality for all patients who underwent mitral valve replacement was 9.5% (14/147). The mean peak systolic gradient pressure in the aortic position was 5.4 mm Hg overall and 4.27 mm Hg with the size 19 mm valve. There were no embolic episodes in patients who received the ISPX valve in the aortic position. The available data indicate that the rate of peripheral embolism with the ISPX valve compares favorably with that of porcine valves. Considering its hemodynamic advantage, if the longterm durability of the full-orifice Ionescu-Shiley pericardial xenograft valve continues to be confirmed by follow-up studies, it is our opinion that it is the biologic valve of choice.

The effects of temporary pacemaker wire removal on cardiac rhythm were studied in 22 open-heart surgery patients who had temporary pacemaker wires implanted at the time of chest wall closure. During wire removal, 16 patients developed premature ventricular contractions (PVCs), most commonly occurring as single PVCs, and less often as ventricular couplets. The authors recommend that external pacemaker wire removal be accompanied by electrocardiographic monitoring or at least by a short period of careful clinical observation.

Duplication of the atrioventricular (AV) valves is a rare anomaly, more commonly seen in the mitral position. Only 13 cases have been reported in the literature.(1-10) The case described here represents an unusual variant of this anomaly and provides an opportunity to review the pathology and embryologic genesis of duplication deformities of the AV valves.

Recent technologic advances make it possible to measure reliably serum or plasma ionized calcium with a high degree of accuracy. In this study, with the use of 16 mongrel dogs, the quantitation of the hemodynamic response to acute changes in ionized calcium was attempted. It was found that normal cardiac function required a normal level of ionized calcium. In intact animals, severe depression of myocardium is masked by pressor reflexes designed to maintain homeostasis. In their absence, myocardial depression is readily apparent. Animals that are hypercalcemic at the beginning of infusion respond in essentially the same manner. To a degree previously unsuspected, myocardial function depends upon a constant level of ionized calcium.

A patient with acute aortic regurgitation, a dissecting aneurysm with a localized transverse tear just above the aortic valve, and an aortic noncoronary cusp eversion is discussed. The valvular defects were considered to be of recent etiology, and the patient underwent successful aortic valve replacement and repair of the dissection.