Percutaneous transcatheter occlusion of coronary artery fistulas using detachable balloons

Three pediatric patients underwent successful transcatheter coronary artery fistula occlusion using the Debrun system. This latex balloon system offers several advantages over other occlusion systems. First, the balloon delivery and release is controlled. Second, “test occlusions” can be performed that allow simultaneous balloon inflation, coronary cineangiography, and electrocardiographic monitoring. Third, because the balloons are flow-directed, they are easily positioned in properly chosen locations. Finally, the balloons can be constructed to suit the size of the fistula. In this study, two patients received only one balloon; in the other patient two balloons were placed in the same fistula. All fistulas drained into either the right atrium or ventricle and were successfully occluded. After a follow-up period of up to 3 years, no local or systemic reactions to the balloons were recognized. We conclude that detachable balloon occlusion of coronary artery fistulas is a safe, effective alternative to surgical ligation in selected pediatric patients.     

Extracorporeal membrane oxygenation (ECMO) as lung or heart assist

Extracorporeal membrane oxygenation (ECMO) may serve as extracorporeal lung assist (ECLA) in patients with acute respiratory failure (ARF) or as extracorporeal heart assist (ECHA) in patients with low output syndrome (LOS) after open heart surgery. From 1988 to 1992 seven patients underwent ECMO in our hospital; four suffered from ARF and three from LOS. Various bypass techniques were employed. Two ARF patients, aged 58 and 18 years, had veno-venous bypass; in the latter, ECMO was reinstituted as a veno-arterial bypass one week after weaning. In a three-year-old boy, the ECMO outflow tubing was primarily connected to the pulmonary artery, and shortly afterwards relocated to the common carotid artery. In a 31-year-old man with ARF, and three LOS patients, a 56-year-old woman, and two men aged 68 and 70 years, ECMO was veno-arterial with direct access to the ascending aorta. A heparin-coated system was used, and all but one patient, who was treated with warfarin, received a daily low dose of heparin, which was withdrawn after from one to nine days.
Six patients were weaned off ECMO after 4.5 to 21 days. Three ARF patients recovered completely; the child died. In one LOS patient, ECMO was withdrawn due to a poor general condition. Two others were weaned off ECMO and the intra-aortic balloon pump, and the inotropic support was significantly reduced, but both died of multiple system organ failure. Although no firm conclusions can be drawn from these few case reports, the heparin-coated system used as ECLA appears promising, whereas ECHA seems to imply a poor prognosis in patients who are not candidates for cardiac transplantation.     

Thiazolidinediones and congestive heart failure—exacerbation or new onset of left ventricular dysfunction?

BACKGROUND: Patients with diabetes mellitus have a high incidence of coronary heart disease and congestive heart failure (CHF). Thiazolidinediones (TZD) are a new class of pharmacological agents for the treatment of Type 2 diabetes mellitus, which have many beneficial cardiovascular effects. Peripheral oedema and weight gain have been reported in 4.8% of subjects on TZDs alone, with a higher incidence noted in those receiving combination insulin therapy (up to 15%), but there is limited data on the occurrence of CHF. METHODS AND RESULTS: In this paper, we report on six cases of TZD-induced fluid retention with symptoms and signs of peripheral oedema and/or CHF that occurred in subjects attending our diabetic clinic. The predominant finding in all cases was of diastolic dysfunction. All subjects were obese and hypertensive, with 5/6 having the additional risk factor of LVH, 5/6 subjects had microvascular complications, whilst 3/6 were also on insulin therapy. CONCLUSION: We suggest that obese, hypertensive diabetics may benefit from echocardiographic screening prior to commencement of TZDs, as these agents may exacerbate underlying undiagnosed left ventricular diastolic dysfunction.     

导管射频消融治疗房室结折返性心动过速前后心率变异的改变

对２０例房室结折返性心动过速患者在射频消融前后进行心率变异频域和时域分析，以了解射频消融对心脏自主神经系统的影响。结果显示，心率变异的极低频段（ＵＬＦＰ）、低频段（ＬＦＰ）、高频段（ＨＦＰ）及总能谱（ＴＦＰ）均较射频消融前降低（Ｐ〈０．０５）。提示射频消融对心脏交感神经、融交感神经均有损害，而以副交感神经损害为主。     

Detection of Human Heart Rate in Exercises State

作者介绍了一种动态心率检测电路，它能准确、可靠地检出在运动状态下的人体心率。电路采用两种检测技术，一种为双时值ＱＲＳ波检测法，另一种为光电脉搏检测法。     

Antepartum fetal heart rate monitoring: III. Fetal movements and accelerations in fetal heart rate

This third part of the paper deals with the study of the relationships between fetal movements, fetal heart rate accelerations associated with such movements, fetal heart rate instability and neonatal outcome.No correlation has been found between absence of fetal movements and neonatal distress.A correlation has been found between the lack of fetal heart rate accelerations, the flatness of the record and poor neonatal outcome.In extreme situations (i.e. flatness in less than 10% of the record or in more than 80%) the presence or absence of accelerations does not add further useful information. Such information, however, is gained in the intermediary situations (the ‘combined’ recordings) and particularly when the record is between 51 and 80% flat where there appears to be an 85.6% risk to the fetus.Consequently, when trying to analyse an antenatal record it seems advisable to take primarily into account the percentage of flat recordings (providing the records are numerous enough and of sufficient length). Then, in records between 10 and 50% flat, the presence or the lack of spontaneous decelerations requires consideration whereas, when the record is between 51 and 80% flat, it is the presence or absence of fetal heart rate accelerations which is important.     

α_2受体阻滞后肾上腺素诱导的心衰病人血小板的聚集功能

先前的研究表明血小板α_2受体变化表征交感神经突触前α_2受体的变化。为了解心衰病人血小板α_2受体功能状况,我们观察了10例Ⅲ、Ⅳ级心功能的心衰病人及10例配对正常人由肾上腺素诱导的血小板聚集率在α_2受体阻滞前后的变化。结果表明肾上腺素诱导的血小板聚集率在两组无显著性差异,但应用α_2阻滞剂Rauwolscine(0.25mg/L)后,0.25,0.5,1.0mg/L E诱导的心衰病人血小板聚集率显著低于对照组,提示血小板α_2受体在心衰时有数量的减少或(和)功能的降低,表征交感神经突触前NE释放的负反馈机制被抑制。     

Altered neuropeptide Y Y1 responses in mesenteric arteries in rats with congestive heart failure

The aim of the present study was to elucidate if the potentiating effect of neuropeptide Y on various vasoactive agents in vitro is (1) altered in mesenteric arteries from rats with congestive heart failure and (2) mediated by the neuropeptide Y Y₁ receptor. The direct vascular effects of neuropeptide Y and its modulating effects on the contractions induced by endothelin-1-, noradrenaline-, 5-hydroxytryptamine (5-HT)-, U46619-(9, 11-dideoxy-11, 9-epoxymethano-prostaglandin F₂) and ATP, and acetylcholine-induced dilatations were studied in the presence and absence of the neuropeptide Y Y₁ antagonist, BIBP3226 (BIBP3226{(R)-N2-(diphenylacetyl)-N-[(4-hydroxyphenyl)methyl]- -arginine-amide}). Neuropeptide Y, per se, had no vasoactive effect in the arteries. The potency of endothelin-1 was significantly decreased in congestive heart failure rats. Neuropeptide Y and neuropeptide Y-(13–36) potentiated the endothelin-1-induced contraction in congestive heart failure mesenteric arteries. In 20% of the congestive heart failure rats, sarafotoxin 6c induced a contraction of 31±4%. Neuropeptide Y also potentiated U46619- and noradrenaline-induced contractions but not 5-HT-induced contractions in congestive heart failure arteries. In sham-operated animals neuropeptide Y potentiated noradrenaline- and 5-HT-induced contractions. These potentiations were inhibited by BIBP3226. Acetylcholine induced an equipotent relaxation in both groups which was unaffected by neuropeptide Y. In conclusion, neuropeptide Y responses are altered in congestive heart failure rats. The potentiating effect differs between vasoactive substances. Neuropeptide Y Y₁ and non-neuropeptide Y₁ receptors are involved.