Disturbed intracoronary hemodynamics in myocardial bridging: early normalization by intracoronary stent placement

BACKGROUND: The purpose of this study was to evaluate the hemodynamic mechanisms leading to myocardial ischemia in patients with myocardial bridging. Myocardial bridging is known to induce angina and even severe myocardial ischemia. METHODS AND RESULTS: In 12 symptomatic patients with myocardial bridges, quantitative coronary angiography was performed to obtain systolic/diastolic vessel diameters within the bridged segments. Coronary flow velocities, flow reserve, and pressures were determined with a 0.014-in Doppler and a 0.014-in pressure microtransducer. In 3 symptomatic patients, coronary stents were implanted and hemodynamic measurements were repeated immediately and after 7 weeks. An in vitro validation of the pressure measurements was performed. Angiography revealed a systolic diameter reduction of 80.6+/-9.2% and a persistent diastolic reduction of 35.3+/-11% within the bridged segment. Diastolic flow velocities (cm/s) were increased (31.5+/-14.3 within versus 17.3+/-5.7 proximal and 15.2+/-6.3 distal, P<.001). Coronary flow reserve distal to the bridge was 2.5+/-0.5. There was an increased peak systolic pressure within the bridged segment (171+/-48 versus 113+/-10 mm Hg proximal, P<.001). Stent placement abolished the phasic lumen compression, the diastolic flow abnormalities, the intracoronary peak systolic pressure, and clinical symptoms. Coronary flow reserve improved to 3.8+/-0.3. CONCLUSIONS: Coronary hemodynamics in myocardial bridges are characterized by a phasic systolic vessel compression with a localized peak pressure, persistent diastolic diameter reduction, increased blood flow velocities, retrograde flow, and a reduced flow reserve. These alterations may explain the occurrence of symptoms and ischemia in these patients. Intracoronary stent placement abolished all hemodynamic abnormalities and may improve clinical symptoms in otherwise unsuccessfully treated patients with myocardial bridges.     

Dislodgement of a Wiktor stent during intracoronary ultrasound examination

We report a case of stent dislodgement complicating adjuvant intracoronary ultrasound (ICUS) imaging that required emergency coronary bypass grafting. This probably very rare complication gains importance since ICUS is increasingly used to confirm adequate stent expansion and full coverage of the lesion.     

Spontaneous thoracic spinal cord herniation through an anterior dural defect

A 44-year-old woman was examined for progressive left lower extremity weakness and spasticity. Thoracic spine MR imaging and CT myelography showed a ventral dural defect at T7-T8 with an extradural subarachnoid fluid collection and extradural herniation of the spinal cord. Intraoperative sonography confirmed the appropriate level for dural entry and the finding of spinal cord herniation. After reduction of the herniated spinal cord, the patient experienced gradual improvement in neurologic function.     

Bowel herniation through the torn diaphragm: I. Gastric herniation

Six cases of gastric herniation through the lacerated diaphragm are presented. Plain radiographs and single-contrast barium examinations demonstrate simple signs that either have not been previously published or need restatement. Some pitfalls that still delay diagnosis are also shown.     

In-laboratory removal of femoral sheath following protamine administration in patients having intracoronary stent implantation

Two hundred twenty-eight patients with successful coronary stent implantation were randomized either to protamine administration and femoral sheath removal (group I, n = 117) or no heparin neutralization and delayed sheath removal (group II, n = 111). The hospital stay after treatment was shorter in patients receiving protamine; therefore, protamine use for neutralizing circulating heparin may be safely administered immediately after stent implantation.     

Single-center experience with the Palmaz-Schatz intracoronary stent: the immediate results and medium- and long-term follow-up

The yeast SEC14 gene product is required for the transport of proteins from the Golgi complex. We have cloned the homologous Candida albicans SEC14 gene (CaSEC14) by functional complementation of a Saccharomyces cerevisiae thermosensitive mutant, sec14ts. Some putative TATA boxes have been identified in CaSEC14 and, contrary to S. cerevisiae SEC14, no introns were found in the Candida homologue. Sequence analysis revealed that CaSec14p is a 301 amino acid protein, 67% identical to S. cerevisiae and Kluyveromyces iactis Sec14p, and 61% identical to the 300 amino-terminal residues of Yarrowia lipolytica Sec14p. Hydrophatic profile analysis of CaSec14p suggests a soluble protein without transmembrane domains as has been described for the S. cerevisiae counterpart. While it was easy to disrupt one allele of SEC14 in C. albicans, repeated attempts to disrupt the second allele were unsuccessful, thus suggesting that the gene could be essential for vegetative growth in C. albicans.     

Distortion of Palmaz-Schatz stent geometry following side-branch balloon dilation through the stent in a rabbit model

In this prospective study, we have compared women undergoing laparoscopic cholecystectomy, laparoscopic gynaecological surgery and laparoscopic minor gynaecological procedures (diagnostic, tubal, ligation) (n = 10 in each group) to determine if lower abdominal laparoscopy results in less postoperative pulmonary dysfunction than upper abdominal laparoscopy. Pulmonary testing was performed before operation, and 3 and 6 h after operation, on the first and second days after surgery. After operation, a significant reduction in forced vital capacity, forced expiratory volume in 1 s and peak expiratory flow rate occurred after laparoscopic cholecystectomy at each time. There were no significant changes after minor gynaecologic laparoscopy, whereas laparoscopic gynaecological surgery resulted in minor pulmonary dysfunction on the day of surgery only. We conclude that postoperative pulmonary function was less impaired after gynaecological laparoscopy than after laparoscopic cholecystectomy. This study suggests that the site of surgery is an important determinant of lung dysfunction after laparoscopy.     

Placement of a coated stent in esophagotracheal fistula: initial experience with an "aortic stent"

Clinical and biological pitfalls that lead to incorrect or delayed diagnoses of airport malaria are described based on 7 cases reported from the Paris region in the summer of 1994. We also report the outcome and the epidemiological features of these patients.     

The limbus vertebra: an anterior disc herniation demonstrated by discography

Limbus vertebra results from an intrabody herniation of disc material. It can be mistaken for a fracture, infection, or tumor, resulting in unnecessary invasive diagnostic procedures. A case is presented in which the lesion was diagnosed by discography. Most radiologists are unfamiliar with discograms, yet they are useful because they opacify the anteriorly herniated portion of the nucleus pulposus.     

Clinical trials on intracoronary stenting

The stent is currently taking the lead in the treatment of obstructive coronary artery disease. The interest in this device is not only reflected by the relative number of patients referred for angioplasty and treated with a stent but also by the large number of clinical trials. These can be divided into trials assessing the safety and feasibility of the implantation of second generation or new stents, studies assessing novel treatment strategies and randomized clinical trials. With respect to the latter, they all compare stent implantation with balloon angioplasty. Of major importance will be the comparison of stent implantation with surgical revascularization of obstructive coronary artery disease. The increasing number of therapeutic options, however, confront the physician with the difficult choice and responsibility of selecting the most appropriate treatment. Therefore, systematic and objective evaluation of the available therapeutic approaches by means of appropriately designed trials is imperative. The purpose of this paper is to summarize and to put into perspective the various studies on intracoronary stenting. Distinction is made between observational studies testing a device or evaluating a new concept in intracoronary stenting and randomized clinical trials.     

Small intestinal herniation through the epiploic foramen: 53 cases (1987-1993)

The incidence of epiploic entrapment of the small intestine in horses undergoing celiotomy for colic was 5%. The condition was more prevalent in older (mean 9.81 years) gelding and Thoroughbred horses. Preoperative peritoneal protein level was a good prognostic indicator as it was significantly greater in the nonsurvivor (39.4 +/- 5.10) group than in the survivor group (26.6 +/- 14.0) (P<0.05). Abdominal ultrasonography allowed earlier diagnosis and surgical intervention in nonpainful cases with inconclusive rectal findings. Surgery was completed in 46 horses and 44 horses recovered from anaesthesia. Nine horses were either subjected to euthanasia in surgery (7 horses) or died in recovery (2 horses). Repeat laparotomies were pursued in 27% (12/44) of the horses. Seven horses (16%) showed post operative adynamic ileus which was the most common post operative complication. The incidence (6%) of adhesion formation was lower than previously reported. Other post operative complications included gastric ulceration, liver disease, diarrhoea and weight loss. Short and long term survival rates were 79% (35/44) and 70% (31/44) respectively. Improved rates were attributed to earlier referral and diagnosis and prompt surgical intervention. The aggressive use of repeat celiotomy and a more effective treatment of the endotoxic horse in the perioperative period contributed to survival.     

Plaque mineralisation in vitro

Dental calculus is plaque mineralised by deposition of calcium and phosphate resulting from interactions between the oral microbial plaque flora and components of oral fluids. An artificial-mouth microcosm dental plaque culture system has been developed to study aspects of plaque mineralisation, including pH control. Five plaques were grown from saliva under simulated oral conditions in a mucin-containing medium, and sucrose was applied to mimic meals. The plaques were mineralised with a urea-based, calcium-phosphate-monofluorophosphate-urea (CPMU) mineralising solution. Alkaline pH oscillations were generated by the plaques in response to CPMU applications, and an acidic oscillation followed sucrose applications. Plaque mineralisation by the CPMU procedure was almost totally dependent on the urea present in the mineralising solution, but total mineralisation also increased as the resting pH increased as a result of urea in the medium. Following four CPMU applications with a sucrose application every 12 hours improved plaque viability and mineralisation. The plaque mineral formed resembled a carbonated hydroxyapatite; other potential calcium phosphate minerals were undetectable except for calcium carbonate. A wide range of mineral deposition patterns in plaque were seen by electron microscopy.     

Plaque removal with variable instrumentation

The purpose of this study was to evaluate dental plaque removal in a normal healthy mouth, during routine oral hygiene appointments using different techniques and without the use of any disclosing agents. 12 dental hygienists, randomly selected from a continuing education course, were asked to perform oral hygiene on the same patient to remove all the supra-gingival plaque without any time restriction and without the use of a disclosing agents. The plaque index score (O'Leary) was assessed before and after each session with the use of fluorescine and UV light source by an independent examiner. 3 groups of instruments were utilized: group A: ultrasonic scalers + prophy cups; group B: ultrasonic scalers + prophy cups + dental floss; group C: Gracey curettes + prophy cups. While no group was able to remove all the plaque, groups B and C performed significantly better.