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Although pulmonary hypertension is frequently mentioned as a complication of the sicklemic state, careful review of the medical literature revealed only a single subject in whom cardiac catheterization data substantiated this diagnosis. In two additional patients, both clinical and autopsy findings of pulmonary vascular disease and cor pulmonale were described, although no hemodynamic studies had been performed. We have therefore detailed the clinical history, cardiac catheterization results, and autopsy findings in three previously undescribed patients. These three patients, along with the three case reports culled from the medical literature, form the substance of this review. Pulmonary hypertension should be suspected in patients with sickle hemoglobinopathy in whom either fixed dyspnea or unexplained syncope develops. Early in the course of the disease, right heart catheterization remains the only way to establish the diagnosis with certainty. Noninvasive studies such as chest x-ray, electrocardiography, and echocardiography tend to be nondiagnostic until late in the course of right ventricular failure. Although specific therapy has yet to be defined, the ominous prognosis of this complication of sickle hemoglobinopathy supports the application of experimental modalities such as continuous oxygen therapy, partial exchange transfusion, or even limited phlebotomy. 相似文献
956.
P S Puri 《The American journal of cardiology》1975,36(2):244-251
The effects of coronary reperfusion on recovery of regional myocardial contractility and high energy pegmental changes in myocardial contractility were measured by means of a strain gauge-tipped, two-pronged catheter probe that measures myocardial fiber shortening. The curves of contraction are sensitive to the effects of ischemia. Coronary occlusion resulted in a rapid replacement of fiber shortening by passive fiber lengthening. If coronary occlusion was released and blood flow restored within 45 minutes, myocardial contractility returned promptly; adenosine triphosphate and creatine phosphate values were restored to normal. With coronary occlusion of 1 hour or longer, contractility failed to return in the immediate postperfusion period, but delayed return was recorded after 2 weeks of reperfusion. The extent of such recovery varied with the duration of preceding occlusion. Thus, reperfusion after 1 hour of occlusion was followed by return of fiber shortening over the entire reperfused region. With 2 hours of occlusion, recovery occurred over 75 percent of the reperfused myocardium. With 3 hours of occlusion followed by reperfusion, recovery of contractility was only partial, comprising approximately 60 percent of the reperfused region. High energy phosphate content of the reperfused myocardium showed a similar pattern of recovery. With occlusion of longer duration, reperfusion failed to restore contractility to any significant extent. These findings indicate that reperfusion after coronary occlusion of 1 to 3 hours may restore contractility over a period of 2 weeks, but the extent of such recovery diminishes with the increase in the duration of occlusion. 相似文献
957.
958.
James O. Menzoian Joseph C. Sequeira Jeanne E. Doyle Nancy L. Cantelmo Michael Nowak Kevin Tracey Richard Zimmerman Peter J. Mozden 《American journal of surgery》1983,146(5):581-585
We have reviewed our experience with the treatment of 250 patients with deep vein thrombosis diagnosed by contrast venography. The level of thrombosis was recorded according to the anatomic level to which it extended. A third of the patients had cancer, and the most common clinical findings were swelling and pain. The risk of the development of pulmonary embolism, based on the anatomic level of initial deep vein thrombosis, revealed the following: 12 of 115 patients (10 percent) with level I (calf) deep vein thrombosis developed pulmonary embolism, as did 2 of 27 patients (7 percent) with level II (popliteal) disease, 5 of 60 (8 percent) with level III (thigh) disease, 1 of 19 patients (5 percent) with level IV (groin) disease, and 2 of 26 patients (8 percent) with level V (iliac) disease. Based on our favorable experience with heparin we believe that heparin is the treatment of choice for deep vein thrombosis regardless of the anatomic level. The incidence of pulmonary embolism does not appear to be influenced significantly by the level of the deep vein thrombosis. 相似文献
959.
Charles G. Watson David L. Steed Alan G. Robinson Leonard J. Deftos 《Metabolism: clinical and experimental》1981,30(6):588-589
Permanent hypocalcemia complicating thyroidectomy is a rare complication, whereas transient post-thyroidectomy hypocalcemia occurs frequently. Ten patients were studied in an attempt to elucidate the underlying mechanisms. An early and transient postoperative rise in calcitonin (CT) corresponding to a decline in calcium levels was demonstrated. Though there was no significant depression of parathyroid hormone (PTH) levels, the failure of the parathyroids to respond to hypocalcemic stimuli suggests a degree of at least transient parathyroid insufficiency. Transiently elevated CT levels appear to play a significant role in the commonly observed early, transient post-thyroidectomy hypocalcemia following subtotal and total thyroidectomy. 相似文献
960.
W. Troni 《Journal of the neurological sciences》1981,51(2):235-246
The conduction velocity in the different partial segments of the monosynaptic pathway of the lower limbs has been assessed in 50 unselected diabetic patients in order to evaluate the distribution of conduction slowing in the entire course of peripheral nerves in the most common form of polyneuropathy.According to the method previously described (Troni 1981), the conduction velocity in the entire course (popliteal fossa-to-spinal cord), in the proximal segment (buttock-to-spinal cord) and in the distal segment (pf-to-buttock) of the H pathway, has been determined and expressed by mixed (sensory-motor) conduction indexes. Moreover, the conduction velocity of the la afferent and of the motor fibres, has been selectively evaluated in the pf-to-buttock segment.The comparison between the impairment of each partial conduction parameter proves the existence of a clear-cut proximo-distal gradient of conduction slowing in the H pathway in diabetic polyneuropathy.Marked slowing in the large-diameter la afferent fibres can also be demonstrated in the pf-to-buttock segment. 相似文献