Left atrial pressure reduction for mitral stenosis reverses left atrial direction-dependent conduction abnormalities.

AIMS: Left atrial (LA) stretch-associated electrophysiological changes in patients with mitral stenosis (MS) predispose to atrial fibrillation. We hypothesized that the normalization of the pressure gradient by percutaneous transvenous mitral balloon valvotomy (PTMV) affects LA but not right atrial (RA) conduction, depending on the site of stimulation. Because direction-dependent (asymmetric) changes of conduction may contribute to arrhythmogenesis, we assessed conduction symmetry in MS patients and tested whether it is restored by PTMV. METHODS AND RESULTS: In nine patients with MS, atrial effective refractory period and local activation times (ATs) were determined during stimulation before and after PTMV, with up to four decapolar catheters (LA and RA). Eight patients with ventricular pre-excitation served as controls. ATs at basic cycle length were similar before and after PTMV. With stimulation from either atrium, they were about 45 ms in the ipsilateral atrium and about 115 ms in the contralateral atrium. With premature stimulation, ATs increased dramatically. The shortest ATs were found in the RA with RA stimulation (78 +/- 9 and 80 +/- 6 ns, before and after PTMV). PTMV caused a shortening in LA-ATs (following LA stimulation) from 118 +/- 14 to 82 +/- 5 ms (before and after; P < 0.05). Asymmetry in conduction properties was therefore normalized by PTMV. PTMV led to a decrease in RA-ATs (following LA stimulation) from 196 +/- 11 to 174 +/- 13 ms (P < 0.02). In addition, following RA stimulation, the dispersion in ATs in the LA decreased significantly by PTMV (from 66 +/- 10 to 34 +/- 7 ms; P < 0.02). CONCLUSION: MS is associated with LA conduction delay, increased LA dispersion of conduction, and conduction asymmetry. These changes are immediately reversible by PTMV.

Percutaneous transcatheter closure of atrial septal defects: initial single-centre experience and follow-up results. Initial experience with three-dimensional echocardiography.

OBJECTIVE: Registry to report our single-centre experience in closing defects of the atrial septum. METHODS: Between 1996 and 2001, transcatheter device closure of significant atrial septal defects was performed in 32 adults (mean age 45.1 years, range from 15 to 76 years), using different device types. Six patients had a patent foramen ovale (PFO) and 26 patients had a secundum atrial septal defect (ASD II). Defects were selected by means of two-dimensional transoesophageal echocardiography (2D TOE). For 12 defects additional three-dimensional transoesophageal echocardiography (3D TOE) was performed. RESULTS: Mean balloon-stretched diameter was 19.3 mm (range from 11 to 24 mm). A device was successfully placed in all PFO patients (100%) without complications at follow-up. Successful immediate device placement occurred in 24 out of 26 ASD patients. Two immediate placement failures, 1 device embolisation and 1 device non-fixation, occurred and required urgent surgery. There was 1 patient with pericardial effusion after the intervention, requiring pericardiocentesis. Three late placement failures occurred: 2 device embolisations and 1 device dislocation. Clinical success after 3 to 6 months follow-up, defined as the absence of shunt or small shunt, was achieved in all 6 PFO patients and in 21 out of 23 ASD patients (1 device embolisation, requiring surgery, occurred before follow-up was completed). Two patients with significant shunt, 1 late device dislocation and 1 late device embolisation, underwent elective surgery. For patient selection, 3D TOE proved useful in the evaluation of large and/or complex defects. CONCLUSION: Transcatheter device closure of carefully selected atrial septal defects is an alternative to surgery. Although the results are promising, surgical back-up is often needed.

Carotid angioplasty and stent placement: comparison of transcranial Doppler US data and clinical outcome with and without filtering cerebral protection devices in 509 patients.

PURPOSE: To prospectively evaluate emboli detected at transcranial Doppler ultrasonography (US) and outcome of carotid angioplasty and stent placement and compare these findings in patients treated with the use of filtering cerebral protection devices (CPDs) with the findings in patients treated without the use of filtering CPDs. MATERIALS AND METHODS: This study was approved by the institutional human research committee. Written informed consent was obtained for all patients. Patients were divided into three groups: 161 patients treated before filtering CPDs had become available (group 1), 151 patients treated with filtering CPDs (group 2), and 197 patients treated without CPDs after CPDs had become available (group 3). Clinical end points were cerebral ischemic events and death. Transcranial Doppler US end points included isolated microemboli, microembolic showers, macroemboli, and distal thrombus. The procedure was divided into five phases: wiring, predilation, stent deployment, postdilation, and CPD handling. Data not distributed normally were analyzed with the Mann-Whitney U statistic. For binomial data, the chi(2) test was used. P < .05 indicated statistical significance. RESULTS: For each phase, median and interquartile range (IQR) for isolated microemboli in group 2 versus group 3 were as follows: wiring, 51 (IQR, 31-69) versus 27 (IQR, 15-48); predilation, 19 (IQR, 13-33) versus 13 (IQR, 8-19); stent deployment, 64 (IQR, 46-82) versus 48.5 (IQR, 33.25-66); and postdilation, 24 (IQR, 14-39) versus 16 (IQR, 11-27.5) (P < .001 for each phase). Median and IQR for microembolic showers were as follows: wiring, 0 (IQR, 0-3) versus 0 (IQR, 0-0); predilation, 1.5 (IQR, 0-4) versus 0 (IQR, 0-2); stent deployment, 22 (IQR, 11-36) versus 11 (IQR, 6-17); postdilation, three (IQR, 0-9) versus one (IQR, 0-4); (postdilation phase, P = .001; all other phases, P < .001). Median for isolated microemboli in group 1 versus groups 2 and 3 combined were as follows: predilation, 10 (IQR, 5-22.75) versus 16 (IQR, 9-25) (P = .001); stent deployment, 32 (IQR, 15-58) versus 54 (IQR, 40.5-74) (P < .001); and postdilation, 11 (IQR, 6-19) versus 18 (IQR, 12-33) (P < .001). Median for microembolic showers during stent deployment were six (IQR, 1-14) versus 13 (IQR, 7-26) (P < .001). Five patients died, and five major strokes and 14 minor strokes occurred. Eight macroemboli occurred in unprotected procedures; six distal thrombi occurred in protected procedures. CONCLUSION: Carotid angioplasty and stent placement yielded more microemboli in patients treated with filtering CPDs than in unprotected procedures. The infrequent occurrence of cerebral sequelae did not allow comprehensive statistical comparison between groups.

Cutting balloon for in-stent restenosis: acute and long-term results.

INTRODUCTION: Conventional percutaneous coronary intervention for the treatment of in-stent restenosis (ISR) has shown a high rate of ISR (30-55%). Considering the need for both extrusion of hyperplastic intima and additional stent expansion, a cutting balloon might be more effective for the treatment of ISR. METHODS: We prospectively assessed the immediate and 8-month outcome of balloon angioplasty using the Barath Cutting Balloon in 100 consecutive patients (mean age: 60.5 +/- 10.8 years, 71% male). RESULTS: In 73 lesions (73%), a good result was reached with the cutting balloon only. In 21 lesions (21%) postdilatation and in 6 lesions (6%) predilatation with a conventional balloon was necessary. The mean inflation pressure was 8.7 +/- 2.0 (range: 6.0-18.0) atm. Before the procedure the mean minimal luminal diameter (MLD) was 0.95 +/- 0.45 mm. Quantitative coronary analysis showed a mean diameter stenosis of 65%+/- 16%. Immediately after the procedure the mean MLD was 2.42 +/- 0.54 mm with a mean diameter stenosis of 19%+/- 13%. Two patients died during the follow-up period (1 stroke, 1 nonvascular). At 8-month follow-up 26 patients (26%) reported to have anginal complaints CCS class II-IV of whom 16 (16%) needed target lesion revascularization. CONCLUSION: Treatment of ISR using the Barath Cutting Balloon can be performed safely with good immediate results and a relatively low need for repeated target lesion revascularization at 8-month follow-up.

Primary stenting of occluded native coronary arteries: final results of the Primary Stenting of Occluded Native Coronary Arteries (PRISON) study.

BACKGROUND: Primary intracoronary stent placement after successfully crossing chronic total coronary occlusions may decrease the high restenosis rate at long-term follow-up compared with conventional balloon angioplasty. METHODS: In a prospective, randomized trial, balloon angioplasty was compared with stent implantation for the treatment of chronic total occlusions. Patients were followed for 12 months with angiographic follow-up at 6 months. Quantitative coronary analysis was performed by an independent core lab. RESULTS: A total of 200 patients were enrolled. Baseline characteristics were evenly distributed. After the procedure the mean minimal luminal diameter in the conventional group was 2.34 +/- 0.46 mm versus 2.90 +/- 0.41 mm in the stented group (P <.0001). The 6-month angiographic follow-up showed a mean minimal luminal diameter of 1.57 +/- 0.74 mm in the conventional group versus 1.93 +/- 0.85 mm in the stented group (P =.009) and a mean diameter stenosis of 44.7% +/- 25.0% versus 35.5% +/- 26.5% (P =.036). Binary angiographic restenosis (>50% diameter stenosis) was seen in 33% in the conventional group versus 22% in the stented group (P =.137). The reocclusion rates were 7.3% and 8.2%, respectively (P = 1.00). At 12 month follow-up, the rate of target lesion revascularization was significantly higher in the conventional group (29% versus 13%, P <.0001). CONCLUSION: These data demonstrate that stenting of chronic total occlusions is superior to balloon angioplasty alone with a statistically significant reduction in the need for target lesion revascularization and a lower, but not significant, restenosis rate.

Additional value of three-dimensional transesophageal echocardiography for patients with mitral valve stenosis undergoing balloon valvuloplasty.

The objective of this study was to validate the additional value of 3-dimensional (3D) transesophageal echocardiography (TEE) for patients with mitral valve stenosis undergoing percutaneous mitral balloon valvotomy (PTMV). Therefore, in a series of 21 patients with severe mitral valve stenosis selected for PTMV, 3D TEE was performed before and after PTMV. The mitral valve area was assessed by planimetry pre- and post-PTMV; the mitral valve volume was assessed and attention was paid to the amount of fusion of the commissures. These results were compared with findings by 2-dimensional transthoracic echocardiography using pressure half-time method for assessment of mitral valve area, and were analyzed for the prediction of successful outcome. Pre-PTMV the mitral valve area assessed by 3D TEE was 1.0 +/- 0.3 cm(2) vs 1.2 +/- 0.4 cm(2) assessed by 2-dimensional transthoracic echocardiography (P =.03) and post-PTMV it was 1.8 +/- 0.5 cm(2) vs 1.9 +/- 0.6 cm(2) (not significant), respectively. The mitral valve volume could be assessed by 3D TEE (mean 2.4 +/- 2.5 cm(3)) and was inversely correlated to a successful PTMV procedure (P <.001). The 3D TEE method enabled a better description of the mitral valvular anatomy, especially post-PTMV. We conclude that 3D TEE will have additional value over 2-dimensional echocardiography in this group of patients, for selection of patients pre-PTMV, and for analyzing pathology of the mitral valve afterward.

Is direct stent implantation without predilatation safe? Acute and long-term outcome.

Direct stenting could potentially lead to a reduction in dissections, time, and restenosis at 6-month follow-up. Using the premounted Palmaz-Schatz Crown stent elective stenting was performed without predilatation in 61 consecutive patients who were compared with a control group of provisional stenting. All patients underwent clinical and angiographic follow-up at 6 months. Direct stenting was successful in 81% of patients. In 16% of the patients predilatation was needed. In 3% the stent could not be implanted despite predilatation. Stent dislodgment occurred in 2% of patients, without embolization. Six-month angiographic follow-up was performed in 51 (84%) of 61 patients. In the direct stenting group the mean preprocedural minimal luminal diameter (MLD) increased from 0.96 +/- 0.47 to 3.09 +/- 0.54 mm directly after the procedure. At 6-month follow-up the MLD measured 2.32 +/- 0.79 mm. In the provisional stenting group the mean MLD increased from 0.92 +/- 0.51 to 2.44 +/- 0.58 mm and was 1.84 +/- 0.70 mm at 6-month follow-up. Restenosis, defined as a diameter stenosis > 50%, occurred in 8% of the direct stenting group compared with 28% in the provisional stenting group (P < 0.001). Direct coronary stent implantation can be attempted safely and efficaciously. The risk of stent loss is low. The initial and long-term angiographic results are significantly better as compared with provisional stenting. The risk of restenosis is significantly lower.

Angioplasty for coarctation in different aged patients.

BACKGROUND: Differences in the indication and outcome of balloon angioplasty for coarctation in children and adults have not been elucidated sufficiently. The results of balloon angioplasty for coarctation are compared between pediatric and adult age groups. METHODS: Balloon angioplasty for coarctation of the aorta was performed in 85 patients who were classified according to age and native coarctation/recoarctation. Groups A (patients aged <16 years, n = 32) and B (patients aged > or =16 years, n = 17) included patients with native coarctations. Groups rCoA A (patients aged <16 years, n = 33) and rCoA B (patients aged > or =16 years, n = 3) included patients with recoarctations. Follow-up included 2-dimensional Doppler scanning echocardiography and additional angiography or magnetic resonance imaging. Gradient reductions in groups were compared by use of the independent-samples t test. Kaplan-Meier and log-rank analyses were performed as a means of comparing long-term outcome. RESULTS: No mortality occurred. Immediate success was equal in groups A, B, and rCoA A (94%). Dilatation was unsuccessful in 2 patients in group rCoA B. Pressure gradients decreased 23 mm Hg in group A, 31 mm Hg in group B, 18 mm Hg in group rCoA A, and 11 mm Hg in group rCoA B. Pressure gradient drops, compared between groups A and B, showed a significant difference (P <.001). The length of hospital stay ranged from 12 to 48 hours. The period of follow-up ranged from 6 months to 12 years (mean, 4.9 years). Kaplan-Meier curves of groups A and B are not different, as determined by means of log-rank analysis. No aneurysm formation was encountered. CONCLUSIONS: The results of balloon angioplasty for native coarctation in both selected children and adults are excellent. In recoarctation, we recommend balloon angioplasty in the pediatric patients.

New brain lesions at MR imaging after carotid angioplasty and stent placement.

PURPOSE: To assess, with magnetic resonance (MR) imaging, the number and size of new brain lesions after carotid angioplasty and stent placement (CAS) and to evaluate the association of these new lesions with neurologic deficits and transcranial Doppler ultrasonographic (US) data. MATERIALS AND METHODS: Seventy-two consecutive CAS procedures were performed in 72 patients. Patients underwent neurologic examination before, during, immediately after, and 1 day, 3 months, and 1 year after CAS. MR imaging was used before and after CAS to assess the number of symptomatic and silent new infarctions. Two radiologists reviewed all pre- and postintervention MR images. The radiologists were blinded to the clinical data. RESULTS: Postprocedural MR images showed new lesions on the side of stent placement in 11 patients. In six patients, the new lesions were clinically silent. Two patients had a major stroke, one had a minor stroke, and two had transient ischemic attack. In patients who had had transient ischemic attack or stroke before CAS, the frequency of new lesions at postprocedural MR imaging was higher (23%) than in asymptomatic patients (12%); this difference was not statistically significant (P =.29). There was no statistically significant correlation between embolic load as detected with transcranial Doppler US monitoring and the occurrence of either clinical symptoms or new lesions seen at MR imaging. CONCLUSION: CAS is associated with embolic events. The majority of new lesions seen on postintervention MR images are not detected at neurologic examination.

Efficacy and safety of percutaneous treatment of iatrogenic femoral artery pseudoaneurysm by biodegradable collagen injection.

UNLABELLED: OBJECTIVES; The goal of this study was to assess the safety and efficacy of femoral artery pseudoaneurysm (FAP) closure by collagen injection. BACKGROUND; The FAP is an infrequent but troublesome complication after percutaneous transfemoral catheter procedures. If ultrasound-guided compression repair (UGCR) fails, vascular surgery is indicated. We have developed a less invasive method to close FAPs percutaneously by injecting collagen and, thus, inducing clotting within the aneurysm. METHODS: Via a 9F needle or 11F sheath, a biodegradable adhesive bovine collagen is injected percutaneously into the FAP, guided by angiography from the contralateral site. RESULTS: From 1993 to 2000, compression and UGCR had failed to obliterate 110 FAPs. These patients have been treated by collagen injection. Mean age of the patients was 65.6 +/- 10.2 years (range: 32 to 85 years), and 50% were women. Immediate closure of the FAP was achieved in 107/110 patients (97.3%) without any complication or adverse effect. In one patient the collagen could not be applied due to unfavorable anatomy. One patient needed a second session of collagen injection. In one patient too much collagen was inserted, which resulted in external compression of the artery, and surgical intervention was required. The overall success rate was 108/110 (98%, 95% confidence interval: 93.5% to 99.8%). Among the patients with successful procedures, there were no recurrences during six months follow-up. CONCLUSIONS: The percutaneous treatment of iatrogenic FAP, by injection with collagen, is an effective and safe strategy. This method provides an excellent therapeutic alternative to the traditional surgical management.