Publications

Iatrogenic aortic dissection is a rare but life-threatening complication of coronary artery bypass surgery. We report a case with incidentally detected iatrogenic aortic dissection related to aorta cross-clamping that was successfully managed with watchful follow-up. The decision making was based on 3-dimensional holographic and fluid dynamic analysis guidance.

We have undertaken a prospective randomized trial of one month's antimicrobial therapy for patients with symptomatic relapse of Crohn's disease. Criteria for entry included two major symptoms: fever, abdominal pain, diarrhea, weight loss, abdominal mass or complications (excluding perianal disease); and two hematologic abnormalities: hemoglobin, ESR, albumin, C reactive protein, iron, or total iron binding capacity. Patients were monitored for the aforementioned clinical and hematologic (hemoglobin, albumin, CRP) parameters over six weeks and for changes in fecal flora. Randomization was to four groups: metronidazole alone (M), cotrimoxazole alone (C), metronidazole and cotrimoxazole (C plus M), or double placebo (P). Seventy-two patients entered the study (18=M, 16=C 21=C plus M, 17=P). After two weeks, improvement was reported as follows: M=67 percent, C=17 percent, C plus M=71 percent, P=35 percent. In the metronidazole group, two patients required surgery and one had trouble-some side effects. In the cotrimoxazole group, two had side effects. In the combined group (C plus M), four had troublesome side effects and two of the placebo group (P) required operation. By four weeks, there was no difference in response among the groups: (M=44 percent, C=62 percent, C plus M=57 percent, P=41 percent). Antimicrobials had no effect on fecal flora or hematologic parameters. These results indicate that antimicrobials have little therapeutic potential for relapse of intestinal Crohn's disease.

Background Coronary artery bypass surgery (CABG) has been considered the therapy of choice for patients with unprotected left main (ULMT) coronary stenoses. Selected single-center reports suggest that the results of percutaneous intervention may now approach those of CABG. Methods and Results To assess the results of percutaneous ULMT treatment from a wide variety of experienced interventional centers, we requested data on consecutive patients treated after January 1, 1994, from 25 centers. One hundred seven patients were identified who were treated either electively (n=91) or for acute myocardial infarction (n=16). Of patients treated electively, 25% were considered inoperable, and 27% were considered high risk for bypass surgery. Primary treatment included stents (50%), directional atherectomy (24%), and balloon angioplasty (20%). Follow-up was 98.8% complete at 15±8 months. Results varied considerably, depending on presentation and treatment. For patients with acute myocardial infarction, technical success was achieved in 75%, and survival to hospital discharge was 31%. For elective patients, technical success was achieved in 98.9%, and in-hospital survival was strongly correlated with left ventricular ejection fraction ( P =.003). Longer-term event (death, infarction, or bypass surgery) -free survival was correlated with ejection fraction ( P <.001) and was inversely related to presentation with progressive or rest angina ( P <.001). Surgical candidates with ejection fractions ≥40% had an in-hospital survival of 98% and a 9-month event-free survival of 86±5%, whereas patients with ejection fractions <40% had 67% and 22±12% in-hospital and 9-month event-free survivals, respectively. Nine hospital survivors (10.6%) experienced cardiac death within 6 months of hospital discharge. Conclusions While results for selected patients appear promising, until early post–hospital discharge cardiac death can be better understood and minimized, percutaneous revascularization of ULMT stenosis should not be considered an alternative to bypass surgery for most patients. When percutaneous revascularization of ULMT is required, directional atherectomy and stenting appear to be the preferred techniques, and follow-up angiography 6 to 8 weeks after treatment is probably advisable.

The effect of bradykinin was studied by inhalation in normal and asthmatic human subjects, as well as on human bronchial smooth muscle in vitro. Bradykinin caused cough and retrosternal discomfort in all subjects and bronchoconstriciton in asthmatic subjects. Bradykinin was approximately 10 times more potent than histamine and methacholine, and there was a significant correlation between the subjects' sensitivity to histamine and bradykinin. Bradykinin-induced bronchoconstriction was prolonged when compared with that of histamine and the C-fiber stimulant capsaicin. This bronchoconstriction was subject to tachyphylaxis, which was also associated with desensitization of the subjects to inhaled histamine. The provocative dose causing a 35% fall in specific airway conductance (PD35) was unaffected by aspirin (1 g orally). However, ipratropium bromide (0.25 mg by nebulizer) significantly inhibited the effect of bradykinin, the PD35 being 0.8 µmol (range, 0.16 to 3.4) and 0.15 µmol (range, 0.047 to 1.15) after...

Directional coronary atherectomy is a new technique of coronary revascularization by which atherosclerotic plaque is excised and retrieved from target lesions. With respect to the rate of restenosis and clinical outcomes, it is not known how this procedure compares with balloon angioplasty, which relies on dilation of the plaque and vessel wall. We compared the rate of restenosis after angioplasty with that after atherectomy.

Bronchodilating effects of the novel potassium channel opener HOE 234 were examined in human bronchi in vitro and compared with those of BRL 38227. HOE 234 produced concentration-dependent relaxations of spontaneous tone and of tone increased by methacholine (10(-6) M), with mean EC50 values of 11 nM and 47 nM, respectively (n = 5). The relaxation produced by HOE 234 was 7 and 3.5 fold more potent than that by BRL 38227 on spontaneous and induced tone, respectively, and was inhibited by glibenclamide (10(-5) M). These results suggest that HOE 234 is a potent bronchodilator which activates ATP-sensitive potassium channels in human airways.

No abstract is provided for this article.

Chronic total occlusions (CTO) constitute a major challenge in percutaneous coronary revascularisation (PCI). The development of new interventional strategies, the availability of purpose made tools including dedicated catheters and wires, as well as increasing expertise by the operators, have contributed to the modest success rates which today hover around 75%. Case selection is of utmost importance since failure of this high risk procedure with its typically high radiation doses, high contrast doses and increased complication rates is associated with long term adverse events. Imaging of the coronary arteries using the gold standard of invasive coronary angiography allows characterisation of the chronic total occlusion and is often able to predict the probability of successful recanalisation. Multislice computed tomography (MSCT) is increasingly being utilised as a non-invasive diagnostic imaging modality to detect coronary artery disease. Its ability to provide information on the soft tissue (including plaque) surrounding the lumen has been applied to better define the morphological features of CTOs. In fact, the amount of calcification, tortuosity and actual length of the occluded segment which are established predictors of success, are all better characterised by MSCT. Three dimensional reconstruction of the coronary anatomy and its integration with two dimensional fluoroscopy images during the actual CTO-PCI procedure may help to identify the best angiographic projection, offering a directional guide at the angiographically "missing segment". More technological advances are needed to optimise this multi-modality imaging integration. Whether this will result in better success rates for CTO-PCI is still the subject of ongoing research. It is then that we can evaluate the true benefit of the use of MSCT for CTO against the risk from excessive radiation associated with this strategy.

Objectives To explore the rate, the determinants of success, and the hemodynamic impact of balloon postdilatation (BPD) of self‐expanding transcatheter heart valves (SE‐THVs) Background BPD is commonly used to optimize valve expansion and reduce paravalvular leakage (PVL) after transcatheter aortic valve implantation (TAVI) without clearly knowing its hemodynamic benefits. Methods Patients ( n = 307) who received a SE‐THV were stratified according to whether a BPD was performed or not. Patients who received BPD were stratified according to the severity of PVL remaining after BPD into two groups: Successful BPD (≤mild PVL + BPD) and Failed BPD (moderate‐severe PVL + BPD). Results BPD was performed in 121 patients (39.4%) and was successful in 106 patients (87.6% of attempts). A ratio of the postdilatation balloon diameter to the annulus diameter ≤0.95 was an independent predictor of BPD failure (OR: 10.72 [2.02‐56.76], P = .005). Peak transvalvular pressure gradient (PG) was lower in the Successful BPD group (14[12‐22] mm Hg) than in the Failed BPD group (18[16‐23] mm Hg, P = .029), and did not rise in either group during follow‐up (median [IQR], 364[161‐739] days). Conclusion BPD was performed in 39% of patients who received a SE‐THV, and was successful in the majority of attempts. BPD failure was more likely in patients with a small postdilatation balloon‐to‐annulus diameter ratio. Effective BPD improved THV hemodynamic performance, and this was maintained in the intermediate‐term post‐TAVI.