[Intravascular optical coherence tomography: differentiation of atherosclerotic plaques and quantification of vessel dimensions in crural arterial specimens]. / Intravaskuläre optische Kohärenztomographie: Unterscheidung verschiedener Plaquetypen und Vermessung von Gefässdimensionen in atherosklerotischen Unterschenkelarterien.

PURPOSE: Intravascular optical coherence tomography (OCT) is a new technique based on infrared light that visualizes the arteries with a resolution of 10-20 microm. Intravascular ultrasound (IVUS) is the current in vivo reference standard and provides a resolution of 100-150 microm. This study compared OCT to IVUS and histopathology with respect to the ability to differentiate atherosclerotic plaques and quantify vascular dimensions in peripheral crural arteries ex vivo. MATERIALS AND METHODS: 50 segments of atherosclerotic arteries derived from five amputated human lower extremities were examined. The different plaque types (fibrous, high-lipid content, calcified) were assigned by two independent examiners, and the sensitivity and specificity of OCT in comparison with histopathology as well as intra- and interobserver consensus were calculated. A comparison of OCT with IVUS addressed the parameters: luminal area (LA), vascular wall area (VA) and plaque area (PA). RESULTS: When comparing OCT and histopathology with respect to the differentiation of various plaque types, sensitivities of 81 % and specificities of 89 % for fibrous plaques, of 100 % and 93 % for lipid-rich plaques and of 80 % and 89 % for calcified plaques were achieved (overall correlation 83 %). Intra- and interobserver consensus was very high (kappa = 0.86 and kappa = 0.89, p < 0.001, respectively). There was also a high correlation between quantitative measurements (Bland-Altman plot [LA]: mean bias, 0.1 mm(2) accuracy +/- 1.8 mm(2), r = 0.95 [p < 0.001] Bland-Altman plot [VA]: mean bias, 0.3 mm(2) accuracy +/- 2.3 mm(2), r = 0.94 [p < 0.001] Bland-Altman plot [PA]: mean bias, 0.4 mm(2) accuracy +/- 2.3 mm(2), r = 0.80 [p < 0.01]. CONCLUSION: OCT allows the differentiation of atherosclerotic plaque types in crural arteries with high accuracy compared to histopathology. Quantitative measurements show a high correlation with IVUS, the current reference standard.

High-dose bolus injection of urokinase. Use during cardiopulmonary resuscitation for massive pulmonary embolism.

Bolus administration of high-dose thrombolytic agents has been reported for the treatment of acute pulmonary embolism. We describe the case of a 60-year-old woman who suffered a massive pulmonary embolism with cardiopulmonary arrest 21 h after an exploratory laparotomy. After 20 min of unsuccessful cardiopulmonary resuscitation (CPR), a bolus of 2,000,000 U of urokinase was injected via a peripheral vein. Ten minutes later, the circulatory system stabilized, and the patient survived without subsequent bleeding. In our opinion, bolus lysis made a definitive contribution to the success of the resuscitation. Several other case reports and small series showed successful treatment of pulmonary embolism during similar circumstances using high-dose bolus injection of thrombolytic agents. Mechanical thrombus fragmentation using a pulmonary artery catheter or pulmonary embolectomy has not been shown to be more successful during resuscitation. We conclude that bolus administration of thrombolytic agents during CPR for massive pulmonary thromboembolism may be an acceptable and successful technique, which also is available even in the community hospital setting.

[Successful treatment of a fulminant pulmonary embolism using a high-dose bolus injection of urokinase during cardiopulmonary resuscitation]. / Erfolgreiche Behandlung einer fulminanten Lungenembolie durch hochdosierte Bolusinjektion von Urokinase während der kardiopulmonalen Reanimation.

Experience has shown that the bolus injection of streptokinase during resuscitation in case of fulminant pulmonary embolism considerably improves the prognosis. In the case presented here a 64-year old female patient with a fulminant pulmonary embolism was injected with 2 x 1,000,000 I.U. urokinase after 20 minutes of unsuccessful cardiopulmonary resuscitation. Ten minutes after the second injection the circulation could be stabilised by drugs only. The patient survived without any lasting damage. The mechanism of fibrinolysis during resuscitation is discussed. It is also possible to check the diagnosis during resuscitation using echocardiography or angiography. However, treatment must usually start immediately only on clinical diagnosis. Resuscitation in the case of a pulmonary embolism can even be successful after much longer than one hour. Contra-indications must be ignored in such cases. Side effects, which are usually haemorrhages, can as a rule be treated. In our opinion urokinase should be given by preference in the bolus injection during resuscitation. The exception to this is the primary operation during resuscitation. Pulmonary embolectomy is also possible after unsuccessful fibrinolysis.