Quantification of Mitral and Tricuspid Regurgitation Using Jet Centerline Velocities: An In Vitro Study of Jets in an Ambient Counterflow

A method for quantifying mitral and tricuspid regurgitant volume that utilizes a measure of jet orifice velocity U(0) - m/sec), a distal centerline velocity (U(m) - m/sec), and the intervening distance (X - cm) was recently developed; where jet flow rate (Q(cal) - L/min) is calculated as Q(cal) = (U(m)X)(2)/(26.46U(o)). This method, however, modeled the regurgitant jet as a free jet, whereas many atrial jets are counterflowing jets because of jet opposing intra-atrial flow fields (counterflows). This study concentrated on the feasibility of using the free jet quantification equation in the atrium where ambient flow fields may alter jet centerline velocities and reduce the accuracy of jet flow rate calculations. A 4-cm wide chamber was used to pump counterflows of 0, 4, and 22 cm/sec against jets of 2.3, 4.8, and 6.4 m/sec originating from a 2-mm diameter orifice. For each counterflow-jet combination, jet centerline velocities were measured using laser Doppler anemometry. For free jets (no counterflow), flow rate was calculated with 98% mean accuracy. For all jets in counterflow, the calculation was less accurate as: (i) the ratio of jet orifice velocity to counterflow velocity decreased (U(o)/U(c), where U(c) is counterflow velocity), i.e., the counterflow was relatively more intense, and (ii) centerline measurements were made further from the orifice. But although counterflow lowered jet centerline velocities beneath free jet values, it did so only significantly in the jet's distal portion (X/D > 16, i.e., >16 orifice diameters from the origin of the jet). Thus, the initial portion (X/D < 16) of a jet in counterflow behaved essentially as a free jet. As a result, even in significant counterflow, jet flow rate was calculated with >93% accuracy and >85% for jets typical of mitral and tricuspid regurgitation, respectively. Counterflow lowers jet centerline velocities beneath equivalent free jet values. This effect, however, is most significant in the distal portion of the jet. Therefore, regurgitant jets, although not classically free because of systolic atrial inflow or jet-induced intra-atrial swirling flows, will decay in their initial portions as free jets and thus are candidates for quantification with the centerline technique. (ECHOCARDIOGRAPHY, Volume 13, July 1996)     

Dopamine,dopexamine and dobutamine in liver transplant recipients: a comparison of their effects on hemodynamics,oxygen transport and hepatic venous oxygen saturation

The purpose of this study was to determine the effects of vasoactive treatment with dopamine (DO), dopexamine (DX), and dobutamine (DOB) on hemodynamics, oxygen transport and hepatic venous oxygen saturation (SvhO₂) after orthotopic liver transplantation (OLT). A pulmonary artery catheter was inserted into the right hepatic vein of 17 OLT patients. Timed infusion of DO, DX, and DOB was performed at the following rates: DO at 4 and 8 g/kg per minute, and DOB at 5 and 10 g/kg per minute. Hemodynamics, oxygen transport variables, and SvhO₂ were assessed. Each catecholamine induced a significant increase in cardiac index, oxygen delivery, and SvhO₂. Mean arterial pressure was increased during DO and DOB, but significantly reduced during DX. Each inotrope increased oxygen delivery in parallel with SvhO₂, suggesting a corresponding increase in hepatic oxygen supply. Therefore, it appears that each vasoactive drug may be utilized in OLT patients to provide oxgen delivery without impairment of splanchnic oxygenation.     

Graduated compression stockings in the prevention of deep vein thrombosis in patients with acute myocardial infarction

Venous volume (venous capacity) of the calf is low in patientswith acute myocardial infarction, who also have a high riskof deep vein thrombosis (DVT). The effect of graduated compressionstockings on the venous volume and on the incidence of DVT wastherefore studied in 80 patients aged 70 years and above withacute myocardial infarction. Graduated compression stockingswere randomly fitted to one leg, the other serving as a control,after which the venous volume was measured by strain gauge plethysmography.The incidence of DVT was measured by the ¹²⁵I fibrinogen uptaketest. Venous volume was significantly higher in legs treatedwith graduated compression stockings compared to control legs.DVT developed in eight control legs but not in any leg treatedwith graduated compression stockings (P = 0.003). DVT was alsosignificantly more frequent in women compared to men and themajority of DVT developed in legs with very low venous volumevalues.     

Echocardiographic and color flow Doppler assessment of systemic and pulmonary venous connection and drainage in the neonate with congenital heart disease

Systemic and pulmonary venous anomalies are frequently encountered either as isolated lesions or as a significant component of a more complex lesion in the newborn infant with congenital heart disease. Two-dimensional echocardiography and Doppler techniques (conventional and color flow) have become the primary diagnostic imaging modality in this setting. Precise pre-operative definition of these variable venous connection and drainage patterns is critical as the required surgical procedure may solely be based on exact understanding of the veins' anatomy and physiology. On the systemic venous site, anomalies of superior and inferior venae cavae, innominate vein, and coronary sinus can be equally well imaged with either echocardiography or angiography. However, on the pulmonary venous site, echocardiography and Doppler techniques including color flow mapping are superior to angiography for precise definition of the connection and drainage sites of the individual pulmonary veins.     

静脉溶栓治疗高龄急性心肌梗死患者的临床探讨

目的　探讨静脉溶栓疗法对高龄急性心肌梗死患者的疗效及安全性。 方法　将 82例高龄急性心肌梗死患者随机分为溶栓组和常规治疗组。溶栓组 40例 ,采用尿激酶静脉溶栓加皮下注射低分子肝素钙。常规治疗组 42例 ,除不用尿激酶及低分子肝素钙外 ,其余治疗均与溶栓组相同。 结果　 血管再通率溶栓组为6 5 %(2 6 / 40 ) ,常规治疗组为 14.3%(6 / 42 ) ,两组血管再通率比较差异具有显著性 (P <0 .0 5 )。溶栓组未见严重出血等并发症。住院 4周内病死率为 5 %。而常规治疗组病死率为 2 3.8%(10 / 42 ) ,两组比较具有显著差异性(P <0 .0 5 )。 结论　 尿激酶静脉溶栓治疗高龄急性心肌梗死可以提高冠脉再通率 ,降低死亡率和改善预后 ,是可行性治疗措施。     

超声心动图对儿童完全性肺静脉异位引流诊断价值的探讨

目的　旨在评价超声心动图对完全性肺静脉异位引流 (TAPVD)的诊断价值。方法　对 1987年 9月至2 0 0 2年 11月收治的TAPVD患儿 70例进行分析。均有完整的临床及超声心动图资料 ,其中 35例施行了手术治疗。结果　 70例TAPVD的解剖分型为 :心内型 5 2例、心上型 16例、心下型 2例 ,未发现混合型。 35例施行手术 ,32例与术前超声心动图的诊断一致 ;3例与超声心动图诊断不完全一致 ,其超声心动图诊断分别为 :三房心伴继发孔房缺、左房隔膜伴继发孔房缺、原发孔房缺伴卵圆孔未闭 ,而手术结果均显示为心内型TAPVD伴继发孔房缺。结论　超声心动图检查是诊断TAPVD重要且准确的方法 ,并能确定其分型 ,提供精确的解剖及血流动力学资料。在应用超声心动图诊断TAPVD时 ,应注意与三房心、左房隔膜等疾病进行鉴别。     

激光诱导脉络膜视网膜吻合初步实验研究

目的 探讨不同激光能量诱导脉络膜视网膜静脉在家免视网膜分支静脉阻塞眼的吻合成功率及安全性。方法 通过光动力法建立 20只兔眼视网膜静脉阻塞模型,24h后以 50 m 光斑,0.1 s的氪红离子激光的不同能量(A组 800mW.B组 1000mW)诱导脉络膜视网膜静脉间的吻合。对侧无静脉阻塞眼以作对照。在实验1、2、4、6 周时进行眼底照相和荧光眼底血管造影检查,测定吻合成功率。结果 在建立 BRVO模型的 20只眼中。A组诱导成功率 30%,激光对周围组织损伤中等;B组诱导成功率 40%;但激光对周围组织的损伤重。在对照组眼中,1只眼形成脉络膜视网膜静脉吻合。A、B实验组与对照组相比,诱导成功率差异有非常显著性意义(P < 0.001);A、B组之间比较成功率差异没有显著性意义(P > 0.1)。结论 利用激光诱导脉络膜视网膜静脉吻合,在技术上可行,较为安全;但在提高成功率方面尚有待进一步研究。     

Use of totally implantable central venous access ports for high-dose chemotherapy and peripheral blood stem cell transplantation: results of a monocentre series of 376 patients.

BACKGROUND: The complication rate of central venous totally implantable access ports (TIAP), used for high-dose chemotherapy with autologous stem cell transplantation support, has not been fully investigated to date, due to the almost exclusive use of externalised, tunnelled devices in this clinical setting. PATIENTS AND METHODS: During a 66-month period (from 1 January 1997 to 30 June 2002), 376 patients suffering from breast cancer, ovarian cancer, lymphoma or multiple myeloma were treated with high-dose chemotherapy and autologous stem cell transplantation at the European Institute of Oncology (Milan, Italy). A single type of port was used, constructed from titanium and silicone rubber, connected to a 7.8 F polyurethane catheter (Port-A-Cath; SIMS Deltec, Inc., St Paul, MN, USA) inserted into the subclavian vein. They were followed prospectively for device-related complications until the device was removed, the patient died or the study was closed (30 June 2002). RESULTS: No TIAP-related deaths were observed in this series. Seven pneumothoraxes (1.8%) occurred as a complication of TIAP placement, one patient only (0.2%) requiring a tube thoracostomy. Port pocket infection occurred twice in this series (0.53%, 0.01 episodes/1000 days of use), whereas three patients suffered from port-related bacteraemia (0.8%, 0.016/1000 days of use). Infections were successfully treated with antibiotics; all three cases had the ports removed at programme completion. Four cases of deep vein thrombosis were detected (1.06%, 0.022/1000 days of use); low molecular weight heparin was given, followed by oral anticoagulants. Finally, one case of extravasation occurred (0.26%, 0.005/1000 days of use), requiring port removal and local medical therapy. CONCLUSIONS: The use of TIAPs has resulted in a safe and effective option for high-dose chemotherapy deliverance and stem cell transplantation, in spite of inducing severe neutropenia and increasing the risk of sepsis in this category of oncology patient.     

Partial venous thrombosis of the pancreatic allografts after simultaneous pancreas-kidney transplantation

Despite new advances in transplantation, complete venous thrombosis (VT) of the pancreas after simultaneous pancreas kidney (SPK) transplantation usually results in graft loss. Data are limited regarding the outcome and treatment of partial VT of the pancreas allograft. From July 1994 to December 1999, 126 patients with IDDM/end-stage renal disease underwent SPK with systemic bladder drainage at the University of Miami. We retrospectively reviewed our experience regarding the outcome and treatment options of partial VT of the pancreas allografts. From July 1994 to April 1997, partial VT was not seen in the first 66 SPK patients induced with anti-CD3 rnAb and oral or intravenous (i.v.) tacrolimus (TAC) in the operating room. From May 1997 to June 1999, 14 (29%) out of 48 patients had VT. These cases were identified following the i.v. use of TAC with anti-IL-2R antibody-induction therapy (7/15) or without (7/33). Partial thrombosis of the splenic vein (PTSV) was documented in 10 patients, 2 had complete thrombosis of the splenic vein (CTSV), 1 had partial thrombosis of the superior mesenteric vein (PTSMV), and 1 patient had PTSV and PTSMV. These were identified incidentally during routine color Doppler ultrasonography (CDU). None of these SPK recipients demonstrates a change in clinical parameters. The first 8 patients were systemically heparinized, followed by oral anticoagulation, except 1 patient with CTSV. He progressed to complete thrombosis of the pancreas allograft and was treated with percutaneous thrombectomy and urokinase infusion, followed by heparinization and oral anticoagulation. One patient required exploration for bleeding. In an attempt to reduce the morbidity of heparinization, we treated the next 6 patients with PTSV with aspirin followed by serial CDU. All 14 patients had preservation of the endocrine and exocrine pancreatic functions. CDU showed resolution with recanalization of the thrombosed vein(s). From July 1999 to December 1999, 12 SPK recipients were administered TAC orally with or without induction therapy with anti-IL-2R antibody. So far, in this group, VT has not been identified. In summary, a total of 14 out of 126 patients (11%) had isolated VT with a mean follow-up of 36.4 months. Based on our experience, we suggest that extensive VT after pancreas transplantation, including splenic and superior mesenteric VT, be treated with heparin and subsequent oral anticoagulation for 3 months. For more limited, partial splenic VT, aspirin may be sufficient. Follow-up CDU is critical for a successful outcome. The i.v. use of TAC appears to be a risk factor for the increased incidence of VT. Currently, using IL-2rmAb as induction, TAC is started orally on postoperative days 3 or 4 and aspirin on postoperative day 2.     

Quadruplet in vitro fertilization pregnancy complicated by fetal reduction and leiomyoma

A woman had a quadruplet IVF pregnancy with a leiomyomatous uterus. Pregnancy resulted in the birth of one baby after missed abortion of one fetus and selective reduction of two others. The woman had a left deep calf vein thrombosis in the first half of pregnancy.